Comorbidity of opiate dependence and mental disorders

Addictive Behaviors, Vol. 23, No. 6, pp. 767–783, 1998 Copyright © 1998 Elsevier Science Ltd Printed in the USA. All rights reserved 0306-4603/98 $19.00 1 .00

Pergamon

PII S0306-4603(98)00099-9

COMORBIDITY OF OPIATE DEPENDENCE AND MENTAL DISORDERS MICHAEL KRAUSZ, PETER DEGKWITZ, ASTRID KÜHNE, and UWE VERTHEIN University of Hamburg

Abstract — In a 5-year-follow-up study of 350 opiate addicts in contact with a drug help system in Hamburg, 272 clients (78%) were interviewed a second time after 1 year. The objective of the study was to examine the correlation between mental disorders and drug consumption and its relationship to clients’ general life situation. In the majority of the opiate addicts, a pattern of polydrug consumption was observed, but the amount of drugs consumed was clearly lower after 1 year. In the initial survey, a mental disorder according to ICD-10 could be diagnosed for 55% of the sample. Among groups formed by the severity and course of mental disorders or their symptoms, a significant correlation was observed, particularly at the time of follow-up, between the extent of drug consumption and the course of the mental disorder. Other areas, like physical health or social problems/conflicts, were also related to comorbidity (i.e., heavy drug consumption and/or mental disorder). These interrelationships should be taken into account in treatment, care and guidance to increase the prospects for successful treatment. © 1998 Elsevier Science Ltd

Since comorbidity of opiate dependence and mental disorders became a focus of international interest in various studies (e.g., Khantzian, 1985; McLellan, Woody, & O’Brien, 1979; Regier et al., 1990), research has been conducted in the last few years on the topic in the Federal Republic of Germany. The relationship between dependency and mental disorders has been considered to be of greatest importance in numerous methadone studies (e.g., Ministerium für Arbeit, Gesundheit und Soziales des Landes Nordrhein-Westfalen, 1993; Raschke, Verthein, & Kalke, 1996; Zenker & Lang, 1995). When considering the development and maintenance of opiate dependence and in looking for “suitable” treatments, researchers as well as practitioners repeatedly confront the fact that in many cases—especially in chronic drug addicts—the “problem” of drug addiction presents itself as a mixture of diverse (biographical and current) problems and constellations of a great variety of conflicts which elude one-dimensional explanations and treatment approaches. Mental disorders in the strict sense—for example, affective or anxiety disorders according to ICD-10 (Dilling, Mombour, & Schmidt, 1993) or DSM-III-R (Wittchen, Saß, Zaudig, & Koehler, 1989)—seem to be only one component among many others in the development, maintenance or termination of drug addiction. For a review of theories, see Lettieri and Welz (1983) or the summary by Degkwitz, Trüg, Gottwalz, and Krausz (1995). A look at the prevalence of mental disorders in drug addicts, however, demonstrates the great relevance of comorbidity and its possible consequences for treatment (Krausz, Verthein, & Degkwitz, in press). In contrast to this, mental disorders or disturbances in drug takers often remain undiscovered and are not treated in the traditional course of treatment programmes for drug addicts. Assuming there is a mutual Requests for reprints should be sent to Michael Krausz, Klinik für Psychiatrie und Psychotherapie, der Universität Hamburg (UKE), Martinistraße 52, 20246 Hamburg, Germany; E-mail: Krausz@uke. uni-hamburg.de 767

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influence, and thus maintenance, between psychological strain of any kind and drug addiction or consumption habits that are subjectively felt as a problem, this must lead to an inadequate provision of treatment among many drug takers looking for help and relief. In a large, representative study of 20,291 persons in the United States (Regier et al., 1990), an additional DSM-III-R mental disorder was ascertained in more than half the drug addicts (lifetime prevalence: 53.1%). The relative risk of drug addicts suffering from an additional mental disorder was 4.5 times higher than for all other participants in the study. Among opiate addicts, the comorbidity amounted to as much as 65.2%, and the illness risk was 6.7 times higher than for other participants. In particular, phobic and anxiety disorders (31.6%) and affective disorders (30.8%) occurred in nearly a third of the opiate addicts. Schizophrenic illnesses also showed a comparatively high prevalence in this group at 11.4%. In a Dutch study by Hendriks (1990), 152 opiate addicts were surveyed using the Diagnostic Interview Schedule (DIS; Robins, Helzer, Croughan, & Ratcliff, 1981) after approximately 1 week of clinical treatment of drug addiction. The lifetime prevalence of a depressive disorder according to DSM-III amounted to 50.7% (6-month prevalence: 35.5%), and of an anxiety disorder 41.4% (6-month prevalence: 36.2%). In a study by Darke, Swift, and Hall (1994), in which 222 methadone-maintained clients took part, the average depression score from the Beck Depression Inventory was 16.7. Degree of anxiety was evaluated by the State-Trait Anxiety Inventory, resulting in an average of 47.4 points. However, more than half the clients exceeded this by at least 1 standard deviation. According to the authors, the prevalence figures for psychiatric disorders among those in methadone maintenance are comparable with those in opiate users in general. The evaluation studies of German methadone programmes mentioned above also point to a high strain due to psychological disorders or deficiencies. Although with one exception (the evaluation project in North Rhine-Westphalia), no psychiatric diagnosis by ICD-10 or DSM-III-R was carried out, the extent of depression and disturbance due to anxiety disorders was extremely high. In the North Rhine-Westphalia study, psychiatric disorders (DSM-III-R) were established for 70% of the therapy participants: 46% of the cases were personality disorders and, in a further group of 12%, some “other” diagnosis was added. The remaining 12% suffered exclusively from “other disorders,” mainly affective and anxiety disorders. The seriousness of the disorders was classified as “medium” or “grave” in roughly half the cases (Ministerium für Arbeit, Gesundheit und Soziales des Landes Nordrhein-Westfalen, 1993). Raschke et al. (1996) reached the conclusion that more than a third (35%) of Hamburg methadone-maintained clients suffer regularly from depressive disturbances and 14% are affected by frequent states of panic. The connection with continuous drug consumption is emphasized. The additional consumption of prescribed drugs (benzodiazepines, barbiturates) is accompanied by a particularly serious psychological disturbance. According to the physicians attending these methadone-maintained clients, 2% suffer from a schizophrenic disorder (Raschke et al., 1996). Although these evaluations of methadone maintenance suggest a wide distribution of psychological disorders among those participating, studies concerning psychiatric morbidity among opiate addicts in the Federal Republic of Germany that are carried out systematically and according to standardized evaluation methods do not yet exist. A possible exception to this is epidemiological studies—for example, the follow-up study by Wittchen, Essau, von Zerssen, Krieg, and Zaudig (1992). There is a funda-

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mental problem here, however, because the group of opiate addicts, as consumers of illegal drugs in general, is underrepresented in these surveys owing to widespread social marginalization (van de Goor et al., 1994). The research reported in this article was a 5-year follow-up study among Hamburg opiate addicts in contact with the drug help system. Its aim was to examine the effects of comorbidity on the development of drug addiction in the light of relevant individual and social factors and therapeutic interventions. Two questions were of central importance: (a) What part do psychiatric disorders or psychological disturbances/strain play in heroin addiction? (b) What is the contribution and importance of heroin consumption and additional consumption of other substances to different biographical and present life constellations? The comorbidity aspect of the study was aimed especially at the degree to which drug addiction, as a pattern of behaviour that has become problematic, is connected with other deviant or “disturbed” patterns of perception, thought or conduct recorded as psychological disorders in the descriptive psychiatric classification systems. Deviant or “conspicuous” behaviours are seen as resulting, among other things, from a preoccupation with one’s social environment, one’s own psychosocial development and the biographical background. Conspicuous behaviour (dependence or problematic consumption patterns, as well as psychiatric disorders or psychological problems/symptoms) is seen as an individual strategy to cope with problems. The disorders in question are not isolated behaviours but rather regulate the individual-environment relationship and are integrated into the whole lifestyle. The study was designed to be in accord with the emphasis on “dependency” in the BMBF sponsoring programme: “Biological and psychosocial factors in drug abuse and addiction” (Ladewig, 1997). M E T H O D

Two evaluations have now been carried out as part of a prospective follow-up study. The initial evaluation took place during the second half of 1995. A total of 350 opiate addicts in treatment or in regular contact with drug advice centres were interviewed. The first follow-up 1 year later succeeded in reaching 272 of the sample (78%). A further three follow-ups took place at 1-year intervals during the remainder of the study. Carrying out and organizing the follow-ups Carrying out a protracted follow-up among users of illegal drugs, especially on several occasions, is difficult and calls as a rule for a greater effort than, for example, further examinations in somatic medicine. Instability in the lives of many participants in the initial survey necessitated a multigraded “algorhythm of search” in order to trace clients 1 year later. At the beginning of the interview, clients were asked, in addition to their personal particulars, to name persons to whom they related more or less closely (eg. parents, friends, acquaintances) as well as their most important drug advice centre. At the time of follow-up, this information was used in the following order. If the client’s phone number was known, the first attempt was directed at getting in touch by phone (at least three times). At the same time, a letter addressed to the client was sent to his or her address (or that of the first-mentioned contact person) asking them to get into touch. If no answer was forthcoming, the search was continued via the named drug advice centre or treatment institution. In the next step, contact persons like partner, family, relatives and the like were written to or, in exceptional cases, telephoned to ask whether they could give information concerning the client’s whereabouts. In

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some cases contact was established with the help of more distant persons by letter. If even this step was unsuccessful, an attempt was made to trace the present whereabouts of the client with the help of the residents registration office or directory enquiries. For this procedure a separate database was established and was used gradually to organize the procedure. For the next follow-up interview, clients were categorized into 3-month groups, so there is a possibility that an individual follow-up period was 1 to 3 months longer or shorter than 1 year. Survey instruments In the initial survey the following survey instruments were used (among others). To describe the psychosocial situation and the drug consumption, the Addiction Severity Index EuropASI (Kokkevi & Hartgers, 1995; German version: Gsellhofer & Fahrner, 1994) was used: a standardized interview of about 1.5 hours referring to dependence “severity” and need for treatment. In addition, the Severity of Dependence Scale (SDS; Gossop et al., 1995; own translation), the Short Opiate Withdrawal Scale (SOWS; Gossop, 1990: own translation) and the Münchner Alkoholismustest (MALT-S; Feuerlein, Küfner, Ringer, & Antons, 1979) were used. These are carried out by selfrating. With regard to diagnosis of psychological disorders by ICD-10 or DSM-III-R, the Composite International Diagnostic Interview (CIDI; WHO, 1990) was employed. Depression was examined with the Beck Depression Inventory (BDI; Hautzinger, Bailer, Worall, & Keller, 1994). Additionally, the Brief Psychiatric Rating Scale BPRS (Overall & Gorham, 1976) and the Global Assessment of Functioning Scale (GAFS; Axis V of DSM-III-R) were employed as objective ratings by interviewers. In comparison with the initial survey, during the first follow-up survey instruments were reduced. In particular, questionnaires to do with personality disorders and biographical background in the initial survey (not described here) would have resulted in a significant increase in the time needed. Also, the CIDI was not used again. Instead, clients were presented with the Symptom-Checklist (SCL-90-R; Franke, 1995) to survey psychiatric symptoms and syndromes; this is better suited to showing the course of psychological disorders and disturbances than the categorically based CIDI. Finally, the State-Trait Anxiety Inventory (STAI; Laux, Glanzmann, Schaffner, & Spielberger, 1981) was added to the survey instruments. In the main, great care was taken that only standardized and internationally recognized instruments were used in order to ensure maximum comparability with results of other studies and to arrive at largely reliable and valid results. Interviews were carried out by graduate students studying for a doctorate in medicine/psychology, as well as those working specifically on this research project. Use of the ASI and CIDI was accompanied by prior training. The length of both interviews was 2.5 to 3 hours on average, and completion of questionnaires and self-ratings took 1 to 1.5 hours altogether. Because of this relatively long time, the interview and the completion of questionnaires were usually carried out in two separate sessions. With a few exceptions, interviews took place in the institution where the client lived or was regularly in touch with. For their participation, clients received expenses of DM30. Formation of groups: Mental disorders and extent of drug consumption To examine the connection between comorbidity and the course of the drug addiction, three groups differing in severity of mental disorders/disturbances based on psy-

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chiatric diagnoses were formed after the initial survey: Group A opiate addicts without other psychiatric deviance; Group B opiate addicts with a minor psychiatric disorder; and Group C opiate addicts with a grave psychiatric disorder. This global group formation was carried out according to various patterns of psychiatric disorder and time of onset based on clinical psychiatric experience. Group B (“minor disorder”), for example, contained opiate addicts with minor or medium grade depressive episodes, dysthymia, phobic or somatoform disorders arising during the last 6 months. Group C (“grave disorder”) contained those cases in which schizophrenia, a bipolar affective disorder or a severe depressive episode could be ascertained. Also, the occurrence of panic disorders, generalized anxiety disorders and dissociative and eating disorders resulted in a Group C classification. A suicide attempt during the last 30 days and the existence of at least three lifetime diagnoses according to ICD-10 were likewise classified as “grave” mental disorder (for further information, see Krausz, 1997). The overall course of the seriousness of psychiatric disorders or disturbances throughout the follow-up period was described according to global mental strain/disturbance (i.e., using the value marker GSI of the SCL-90-R). First, this operationalization resulted in nine subgroups reflecting the possibility that the client’s mental state could have become better, worse or remained the same in each of the three groups. These combinations of initial status and course were then again summarized in three groups describing the course of the mental disorder as “positive,” “medium” or “negative.” The subgroups “no disorder/GSI positive,” “no disorder/GSI normal” and “minor disorder/GSI positive” were classified as “positive course.” In the groups, “no disorder/GSI negative,” “minor disorder/GSI normal and “grave disorder/GSI positive” a “medium course” was assumed. The three subgroups, “minor disorder/GSI negative,” “grave disorder/GSI normal”and “grave disorder/GSI negative” were classified as a “negative course” of the mental disorder. The division according to the GSI-value marker used the criterion of a standard deviation from the mean value. To gain an impression of the extent of multiple drug consumption that was observable in most cases, a global index reflecting the number of drugs consumed in likely problematic intensity was constructed. Based on the distribution of the length of drug consumption (measured by the ASI), an aggregate score was derived beginning with 80% per substance; that is, in the case of clients among the upper 20% with regard to length of consumption, 1 point was added for the drug in question. The 80% criterion had to apply either to the previous year or to the last 30 days. Note that there is a high correlation between the extent of current drug consumption and consumption in preceding months or years. Thus the index shows a combination of actual and past drug consumption—in the case of the initial survey referring to several years and in the case of the follow-up referring to the last year. By this means, it was ensured that the index mainly reflected significantly more intensive and thus probably more problematic consumption, in contrast to other participants of the survey, in graded form. This global index, however, does not take into account which drug is referred to in each case. In the interests of clear representation and possibly further analysis, the differentiated index scale was organized into four groups representing the intensities “no/little,” “medium,” “much” and “very much” drug consumption. First results from the 1-year follow-up are presented below. This summary of results is limited to a representation of the course of psychiatric symptomatology and the development of drug consumption or the seriousness of drug addiction, in addition to their interrelationships. Readers interested in further details of the prevalence of mental disorders in the initial survey sample should consult Krausz et al. (in press).

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R E S U L T S

Survey group As mentioned above, 78% of clients were contacted again for follow-up (N 5 272). Eleven clients had died during the year between interviews (3%). In four cases, the cause of death was known (overdose 5 2, suicide 5 1, unnatural causes 5 1); another client probably died of a stroke, and two suffered from AIDS. Sixteen persons could not be traced at follow-up (5%) and two clients had been deported (1%). Ten clients (3%) said they did not want to take part in the interview at present but might agree to later interviews. The major proportion of the drop-out was due to failed contact, cancelled dates or other combinations of individual problems. This was the case with 39 clients (11%) for whom a first contact had been established or whose whereabouts were known but who were not interviewed, in some cases after several attempts. All participants in the survey were opiate addicts who typically reported several years of heroin or other opiate consumption. Some had abandoned the heroin habit recorded at the time of the initial evaluation. In nearly all cases, these clients were being maintained with methadone or levomethadone. With regard to sex, age, treatment method and other characteristics, those who were contacted for follow-up (“course sample survey”) differed negligibly from the remaining 78 persons in the initial survey (see Table 1). Apart from differing utilization of therapeutic institutions (more maintained persons and less LZT clients: x2: p , .01), the comparison shows that the 272 clients included in the follow-up survey did not show any selection bias from the initial survey sample (N 5 350). On average, the 272 clients in the follow-up sample were interviewed for the second time after 12.6 months. Thus participants showed an average age of 30.0 years (66.5, min 5 17, max 5 48) and were 1 year older than at the time of the initial inquiry. Generally speaking, their life situation had improved during this time. The utilization of therapeutic institutions had also changed: most were receiving methadone maintenance treatment, while only very few were still being detoxified. The number of inpatients had been reduced by half compared with the initial inquiry. A considerable percentage, nearly a fifth, were not currently receiving treatment (Table 2). Need for treatment according to the ASI From the results of the Addiction Severity Index (ASI), the need for treatment or problems related to the extent of drug consumption also showed a considerable improvement during the previous year. In addition to a multitude of qualitative and quantitative information about the present life situation, the ASI gives seven index values as a main result, describing the need for treatment on a scale from 0 (no real problem, no treatment necessary) to 9 (extreme problem, treatment absolutely necessary). To enable interviewers to differentiate further, two numerical values were assigned to each point to form a five-category scale, the other scale figures representing 2–3 (minor problem, treatment possibly not necessary), 4–5 (medium problem, treatment recommended) and 6–7 (considerable problem, treatment necessary). This was carried out by interviewers using a rating of six topics that were surveyed in standardized fashion during the interview. Going beyond the seven indices, the average total ASI score provides global information on the extent of drug problems and the need for treatment. The average total score of the surveyed group was 3.9 at the initial interview and 3.2 at follow-up and thus as a whole shows a “slight” to “medium” problem situation or need for treatment (Table 3). Values from 6–9 (considerable to extreme problem) applied to only 11% at the initial survey and to 7% at follow-up.

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Table 1. Description of the follow-up survey group in comparison with remaining clients at the time of the initial survey (figures in %)

Sex Male Female Age Under 18 years 19–25 26–30 31–35 Over 35 years Average age Average heroin starting age Present treatment Maintenance Average length of therapy In-Patient LZT Average length of stay Detoxification Average length of stay Ambulant therapy Average length of stay Other treatment No treatment HIV/AIDS status Negative Positive Positive with AIDS symptoms Unknown Living conditions Own flat/with one’s partner Sharing a flat/parents/relatives With friends/hotels/institution/ homeless/other Gainful employment at present Yes No N

Follow-up group

Remainder group

Total

70 30

68 32

69 31

7 22 32 24 15 29.0 (66.5) years 19.8 (64.9) years

10 24 28 22 15 27.9 (66.7) years 19.0 (64.0) years

8 22 31 24 15 28.7 (66.5) years 19.6 (64.8) years

47 18.5 months 19 5.9 months 17 11.3 days 2 10.5 months 9 6

24 20.4 months 35 4.1 months 21 12.9 days 4 27.0 months 13 4

42 18.7 months 23 5.3 months 17 11.7 days 3 15.2 months 10 5

87 6 1 6

85 3 3 10

86 5 2 7

40 20 37 3

42 17 36 5

40 19 37 3

19 81

23 77

20 80

272

78

350

It follows that, except for medical treatment, the need for treatment decreased in all areas; in other words, clients’ life situations became stabilized in the course of the follow-up period. However, statistically significant improvements were shown only in the areas of “need for drug therapy,” “need for advice on family/social conflicts,” “need for psychiatric/psychological treatment” and total ASI score (Wilcoxon: p , .01). Thus ASI scores reflect the changes shown in Table 2. Drug consumption With regard to participants’ drug consumption, information about age of onset, length (in general and in the last 30 days) and method of taking the drug was available for different drugs. This results in an exceedingly complex picture of drug consumption, reflecting multiple consumption among opiate addicts (Table 4). Heroin dose at the time of the initial survey (i.e., before treatment) was a mean of 2.2 grams per day; 1 year later it was 0.9 grams. Before treatment began, 61% of clients had taken their drugs intravenously during the last 30 days; at the time of followup the proportion of clients with intravenous use had fallen to 38%. Most of the sur-

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Table 2. Description of the follow-up survey group at the initial survey and the first follow-up (figures in %, N 5 272)

Present treatment Maintenance Inpatient LZT Detoxification Ambulant therapy Other treatment No treatment Medical treatment because of physical problems Yes No Living conditions Own flat/with one’s partner Sharing a flat/parents/relatives With friends/hotels/institution Homeless/other Gainful employment Yes No Imminent charge/proceedings/conviction Yes No

Initial survey

Follow-up

47 19 17 2 9 6

56 10 3 5 7 18

65 35

72 28

40 20 37 3

53 14 31 3

19 81

31 69

34 66

25 75

veyed persons were exclusively using their own or “clean” injection needles (initial survey 5 72%; follow-up 5 88%). On average, clients had started using heroin just under 20 years previously. This was preceded by experience of alcohol, cannabis, sniffing substances, hallucinogens and amphetamines. It would seem that cocaine and pills such as benzodiazepines or barbiturates are used typically only after heroin consumption has already started and, as shown by data on the length of consumption periods, mainly in the form of concurrent consumption. Clients’ longest experience was for cannabis. On average, heroin was used intensively (at least 3 times per week) over a period of nearly 7 years. On the whole and among all clients, current consumption (during the last 30 days) consisted mainly of heroin, cannabis, pills and cocaine. Alcohol was also drunk, al-

Table 3. ASI scores at the initial survey and the first follow-up (figures in %, N 5 272) Problem areas

Initial survey

Follow-up

Need of medical treatment Need of advice because of problems at worka Need of legal advice Need of alcohol therapy Need of drug therapy Need of advice because of family/social conflicts Need of psychiatric/psychologic treatment

3.0 3.6 2.8 2.2 6.4 4.4 4.6

3.1 2.8 2.6 2.0 4.6 3.2 4.0

Average total ASI score

3.9

3.2

a The

index “need of advice because of problems at work” applies only to clients who work, who are still trainees or have some job. This applies to 204 clients in the inital survey and to 175 clients in the follow-up. (This does contradict the details in Table 2 showing an increase in the percentage of clients in gainful employment because these figures refer only to a steady job on the permanent staff.)

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Table 4. Starting age and length of consumption of various drugs at the initial survey and the first follow-up (average figures, N 5 272) Initial survey Substances Alcohol, any use Alcohol, until drunkenness Heroin Other opiates/analgesics Pills, juicesc Cocaine Amphetaminesd Cannabinoids Hallucinogens Sniffing substances Other substances More than one substance per day

Follow-up

Starting age

Years of consumptiona

Last 30 daysb

Months of consumptiona

Last 30 daysb

12.4 13.8 19.8 21.8 21.6 20.2 19.1 15.1 17.7 15.8 20.0 17.5

5.2 2.6 6.7 1.3 2.4 3.1 0.6 8.0 0.7 0.1 0.1 6.5

7.2 2.0 18.9 3.9 8.3 8.4 0.3 9.4 0.4 0.0 0.5 14.2

4.1 0.5 2.0 1.0 2.1 1.8 0.3 3.7 0.1 0.0 0.1 4.1

8.3 1.1 3.9 2.2 4.3 2.6 0.4 7.5 0.2 0.0 0.4 8.8

a Only of relevance are periods of greater consumption from approximately three times per week upwards. In the case of the follow-up, the details refer to the last 12 months before interview. b Average number of consumption days. In the case of the initial survey, this refers to the time before treatment started (the maintained persons excepted). At the time(s) of the follow-up, it refers to the last 30 days before interview. c Among the clients of our survey, the category “pills, juices” specifically includes benzodiazepines and/or barbiturates which are not surveyed separately in the ASI. d We counted also Ecstasy and related substances as belonging to this group.

though not always as an intoxicant. This results in a consumption pattern showing a preference for simultaneous consumption of several drugs. Most clients named heroin as the “main problem substance” (initial survey 5 44%; follow-up 5 29%). The proportion naming cocaine as the main drug stayed constant at 16% and 15% at each interview, respectively. A problem with the simultaneous consumption of several drugs (in the ASI under the diagnostic category “polytoxicomania”) was admitted by 26% of the clients in the initial survey and by 9% at the time of follow-up. The degree of polydrug consumption based upon the global consumption index is shown in Table 5. It transpires that, at the time of the initial survey, an average of 2.7 drugs for the stated time and with the stated intensity were consumed; at follow-up, this number had fallen to 2.0 (Wilcoxon: p , .01). The proportion of clients who no longer consumed drugs or showed relatively low drug consumption also increased during the follow-up period from 12% to more than a quarter. (These clients may properly be called “clean,” although there may still be some drug consumption which differs significantly, however, from the other participants’ drug habits.) The proportion of opiate addicts with excessive, polydrug consumption was reduced by nearly a half. Table 5. Global index of the drug consumption intensity at the initial survey and the first follow-up (N 5 272) Global index 1. No/little drug consumption (index 5 0) 2. Medium drug consumption (index 5 1–2) 3. Much drug consumption (index 5 3–4) 4. Very much drug consumption (index $ 5) Index average

Initial survey

Follow-up

12% 40% 28% 19%

26% 40% 22% 11%

2.7

2.0

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Prevalence of mental disorders according to ICD-10 and course The lifetime prevalence of mental disorders according to ICD-10 (personality disorders under F6 were not considered here) and assessed by the CIDI in the initial survey amounted to 55% among the 272 participants of the follow-up study. The predominant disorders were from the group of neurotic, strain and somatoform disorders with 43% diagnoses (F4) and from the area of affective disorders (F3) with 31% (Table 6). Thirty percent (30%) of clients had a multiple diagnosis (apart from opiate dependence) with an average of 2.2 disorders. The average number of ICD-10 diagnoses among all clients was 1.2. In addition, there were clear differences between men and women and lifetime prevalence among female clients (65%) was considerably higher than among men (51%). All frequently occurring disorders appeared much more often in the female cases, nearly twice as often as in men. This is also shown in the average number of diagnoses. As expected, the relevant prevalence rates for mental disorders in the last 6 months or the last month are lower. The 6-month prevalence in all surveyed cases was 35% (men 5 31%; women 5 46%) and the 1-month prevalence was 28% (men 5 22%; women 5 44%). The assessed psychiatric diagnoses result in the formation of the groups shown in Table 7 based on the global seriousness of mental disorder at the time of the initial survey and the results of the SCL-90-R regarding the course taken by the mental symptomatology. Once again, the greater extent to which women are affected is evident; their symptomatology and its course are significantly worse than in men. Interrelationships between drug consumption and mental disorders With regard to drug consumption and the groups formed according to seriousness and course of the mental disorder/disturbance, a clear relationship at the time of fol-

Table 6. Lifetime prevalence of mental disorders under ICD-10 (omitting F6 disorders) related to sex (multiple diagnoses, figures in %, N 5 272) Disorder groups

Totala

Men

Women

3 2 4

— 2 2

2 2 4

F31: Bipolar affective disorder F32: Depressive episode F33: Recidivist depressive disorder F34: Continual affective disorder F3

2 12 7 11 26

2 23 16 20 44

2 15* 10* 13* 31**

F40: Phobic disorder F41: Other anxiety disorder F44: Dissociative disorder F45: Somatoform disorder F4

26 10 1 8 38

45 22 9 12 54

32** 14** 3** 10 43*

1 1

10 10

4** 4**

49

35

F20: Schizophrenia F25: Schizo-affective disorder F2

F50: Eating disorders F5 No mental disorder Average number of diagnoses a x2

test. * p , .05. ** p , .01.

0.9

1.9

45* 1.2**

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Table 7. Group formation according to degree of global gravity of the mental disorder at the initial survey and according to course in terms of global mental strain (GSI) from the SCL-90-R (figures in %, N 5 272) Group formation

Men

Women

Totala

40 36 24

28 28 44

36 33 30

40 38 22

31 26 43

37 34 29

Mental disorder at the time of initial survey No Minor Grave Course of mental disorder Positive Medium Negative ax2

test; p , .01.

low-up is discernible. Clients whose symptoms show a negative development have a distinctly raised drug consumption compared with the rest of the survey participants (x2: p , .01, Spearman’s r 5 .21, p , .01). At the time of the initial survey this correlation appeared only as a tendency (r 5 .12, p , .05; Table 8). It is only when considering the course dynamics of the mental disorders that the relationship becomes clear. Although comorbidity affects female clients to a higher degree, these interrelationships apply equally to men and women. (A two-factor analysis of variance of drug consumption according to extent/course of the mental disorder and gender showed no main effects over time and there were no significant interactions.) With the assistance of different survey instruments, the relationship between the extent of drug consumption and mental disorders can also be described in correlational terms. The number of lifetime diagnoses by ICD-10 was related to drug consumption established in the initial survey (r 5 .15, p , .05). At follow-up, correlations between the drug consumption index and depression according to the BDI (r 5 .40, p , .01) and between the drug consumption index and “trait-anxiety” from the STAI (r 5 .33,

Table 8. Drug consumption (global index) related to grade of gravity and course of mental disorders (N 5 272) Mental disorder at initial survey Drug consumption

Course of mental disorders (follow-up)

No

Minor

Grave

Positive

Medium

Negative

Global index at initial survey No/little Medium Much Very much Average

17% 42% 24% 16% 2.4

8% 42% 31% 20% 2.8

11% 37% 29% 23% 2.9

17% 42% 24% 17% 2.4

6% 47% 29% 17% 2.7

13% 31% 30% 26% 3.0

Global index at follow-up No/little Medium Much Very much Average

24% 47% 22% 6% 1.8

29% 34% 27% 10% 2.0

27% 39% 17% 17% 2.1

31% 44% 21% 4% 1.6

31% 37% 23% 10% 1.8

16% 39% 25% 21% 2.6

Note. Example: At the time of follow-up, “very much drug consumption” applies to 4% of clients with a positive course of mental symptomatology in contrast to 21% among those with a negative course.

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p , .01) were relatively high. This also applies to the relationship between the drug consumption index and global mental disturbance as assessed by the SCL-90-R (r 5 .41, p , .01) and to the drug consumption index and the level of psychosocial functioning according to GAFS (r 5 .44, p , .01). Furthermore, individual problems in different areas of life or the need for treatment, as established by the ASI, can be shown to depend on the seriousness and course of mental disorders and to the extent of drug consumption. This demonstrates the expected relationship of more problems in various areas (or a greater need for treatment) in clients with a negative symptomatology course and higher drug consumption. Based on the existing relationship between drug consumption and psychiatric morbidity, relationships between mental disorders and ASI scores and between drug consumption and ASI scores were calculated with the other variable partialled out (Table 9). It appears that medical, somatic problems as well as family and social conflicts tend to correlate with mental disorders, whereas relevant legal problems are mainly connected with excessive consumption of drugs. Occupational conflicts are connected with mental disturbances as well as with the extent of drug consumption. As only the present life situation at the time of follow-up is considered here, it is only to be expected that correlations with mental disorders and drug consumption at the time of the initial survey are less prominent.

D I S C U S S I O N

Among 272 opiate addicts currently or previously in contact with the Hamburg drug help system, the lifetime prevalence of an additional psychiatric disorder under ICD-10 is 55%. These disorders are mostly in the areas of neurotic, strain and somatoform disorders (F4) and affective disorders (F3). These results are comparable to prevalence rates reported in other international studies (e.g., Hendriks, 1990; Regier et al., 1990). Personality disorders for which diagnosis is of generally poor reliability (e.g., van den Brink, 1995; Verheul, van den Brink, & Hartgers, 1995) were not considered here.

Table 9. Problems or need for treatment under ASI at the follow-up related to gravity and course of mental disorders and extent of drug consumption: Partial correlations between mental disorders and ASI scores (partialling out the drug consumption) and between drug consumption and ASI scores (partialling out mental disorders) per time of investigation (N 5 272) Initial survey

Follow-up

Mental disorders

Drug consumption

Mental disorders

Drug consumption

Need of medical treatment Need of advice because of problems at worka Need of legal advice Need of alcohol therapy Need of drug therapy Need of advice because of family/social conflicts Need of psychiatric/psychologic treatment

.20b** .21** .09 .12 .11 .23** .27**

.15* 2.02 .03 .14* .09 2.02 .11

.32** .25** .09 .13* .16** .34** .38**

.14* .33* .35** .24** .39** .13* .28**

Average total ASI score

.25**

.11

.36**

.41**

Problem areas (follow-up)

a Compare

with footnote to Table 3. partial correlation: *p , .05; **p , .01.

b Significance

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Surveys of comorbidity among drug addicts using operational psychiatric diagnosis are still fairly rare. Among other reasons, this is probably due to the fact that, as a rule, this research objective meets with little acceptance among those working in the drug help system, due often to an opposition to the increasing menace of a “psychiatrization” of dependence and its treatment. In the German-speaking area, in particular, no comparable study is available, so that results from this follow-up study can be seen as the first indications of a relatively high prevalence of mental disorders/disturbances among opiate addicts in contact with the drug help system in an urban area in the Federal Republic of Germany. Many comorbidity studies have been contributed by clinical psychiatry (see Krausz, Maß, Haasen, & Gross, 1996), but these are mainly confined to drug or alcohol addicts with particularly grave psychiatric disorders. It can only be guessed whether this also applies to drug addicts outside the advice and treatment system as well. Among people connected to the open drug scene, psychiatric disorders may play a significant part too (e.g., Ladewig & Simoni, 1996). However, “drug careers” among socially integrated opiate addicts who are neither seeking treatment nor become criminally noticeable mostly take an inconspicuous course. In any event, very little is known about these drug consumers. Judging by their nonexistent or only sporadic search for admission to therapeutic or care institutions, presumably because a need for treatment is not subjectively felt, it may be assumed that these drug addicts are much less affected by mental disorders/disturbances than the “visible” clients searching for care and support. As a rule, longitudinal follow-up studies of opiate addicts with several follow-ups are difficult to carry out. Because of the mostly unstable lives of many people addicted to illegal drugs, it is often impossible to contact specific clients again. One of the reasons why this study covered only clients in contact with the drug help system is precisely that these clients’ lives are supposedly easier to follow, for example via people working for these institutions, and that by this means there is a greater chance of winning them over to take part again in a survey. Besides, the diagnosis of mental symptoms, as well as the inquiry as a whole, always makes great demands that are easier to accommodate with the help of therapeutic institutions and advice centres. A comparison of the 272 surveyed persons with those not recontacted regarding their situation at the time of the initial survey shows that the follow-up group is no “positive selection” among the initial survey group. The survey group now consists mostly of maintained drug addicts. Only a few clients are still being treated in hospital, and nearly a fifth are receiving no current treatment. This implies, on the one hand, a change in drug-using methods, as well as in the need for treatment, during the followup period; on the other hand, it shows that the maintained addicts in particular were easier to contact again due to their continuous therapeutic contacts. This reflects the typically German situation that long-term substitution treatment still tends to be at the end of the treatment chain. Most opiate addicts look for prolonged therapies and other hospital treatment methods earlier. Although most opiate addicts showed a decrease in drug consumption and an improvement in their life situation during the 1-year follow-up period, the comorbidity problem seemed to play an important part in the individual development of many of those surveyed. Not only the extent of drug consumption but also processes of change in other areas of life were directly connected with the development of mental problems. Based upon the group formation reflecting the seriousness or course of mental symptoms, an exceptionally high drug consumption was shown, especially among clients with grave psychiatric disorders. At the time of the initial inquiry, 52% of these

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clients were consuming “much” or “very much;” the percentage among opiate addicts without mental disorder was 40%. This difference becomes more distinct at the time of follow-up; with regard to the course of the mental symptoms, 46% of clients with negative development but “only” 25% of those with positive development were consuming “much” or “very much.” How far the consumption index used here can be seen as a reliable (if possible, linear) indicator of the extent of drug consumption extent is debatable. Operationalization should result in a global index as simple and clear in its application as possible in order to be able to represent the relationship between mental disorders and drug consumption overall. Differentiating according to different drugs and consumption intensities would have meant more precise individual measurement, but variations in the extent of co-consumption (or the “consumption pattern”) among the opiate addicts would not have been included. The 80% criterion was used to differentiate between relatively low and comparatively high consumption in the survey group. It is true that it is impossible by this means to show that clients with “no/low” consumption also take few different drugs; compared to other surveyed persons, however, the extent of consumption as a whole is distinctly smaller. However, intercorrelational analysis of the variables the index is based on show that these clients are, in fact, those that can mainly be described as “clean.” Presumably the most serious objection to such an index is that the type of drug remains unconsidered. Here too, however, the interrelationships show that clients with high rates are mainly those with high heroin and/or cocaine consumption, and thus high index rates represent “hard” drugs rather than an exclusive use of alcohol and cannabis. This is explained by the fact that, among the opiate addicts we surveyed, consumption of alcohol, cannabis and prescription drugs occurs primarily as co-consumption with heroin (and partly cocaine). By mixing length and current intensity of consumption to establish the index, our aim was to represent exactly this general picture of drug consumption. The lengths of the current (last 30 days) and previous (last years/months) periods of consumption, however, are closely correlated. The direct comparison drawn between drug consumption at the time of the initial and the followup surveys is problematic though, because the first interview refers to the time preceding treatment and a longer retrospective period, whereas the follow-up inquires about present consumption. In addition, the frame of reference used to establish the index differs at each survey occasion due to the 80% criterion. This means that only indications of a change in the consumption pattern can be inferred from the consumption index. All the same, the follow-up results in themselves give quite a reliable picture of the past 1-year period. The subdivision into three groups according to the degree of severity of the mental disorder, with the help of diagnoses under ICD-10 and DSM-III-R, was carried out from practical considerations to compare clients’ course with regard to drug consumption and the life situation. This group division was based upon the presumed requirements of psychiatric treatment. According to psychiatric clinical experience of currently prevailing practice, these requirements follow from the diagnosed disorder. The disorder patterns contained in one group must thus represent a similar need for treatment. The fact that quite different sorts of symptoms and disturbances are combined here does lead to limitations regarding the interpretation of connections, but is of minor importance for the examination of the “comorbidity hypothesis” in principle. It should be noted that examination of individual patterns of disorder (or diagnosis groups) is the subject of further analyses. Whether the division of the follow-up groups

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in terms of the development of mental disorders reliably represents the dynamics of change cannot be unreservedly determined. It is true that the differentiating criterion of the SLC-90-R result is clear, but the severity group division of the initial survey was also influenced by lifetime diagnoses established by the CIDI; in the case of these lifetime diagnoses, a connection with later changes in the psychiatric symptomatology and, following the hypothesis of this study, in the pattern of drug consumption cannot be assumed. The development of mental symptoms should become clearer in the subsequent follow-up enquiries because the SCL-90-R is sensitive to change and thus suited for a description of course (Franke, 1995). This also applies to the BDI and STAI which are suited for the description of a global change in depression and anxiety. So the comparison between psychiatric initial diagnosis under ICD-10 and the change in psychiatric disorders or symptoms with respect to the connection with and change in the client’s life situation will be a central issue for further follow-up study. Although these methodological reservations may have a bearing on the strength of the relationships found and the precision of the underlying interrelationships, there still are clear indications that the development of a “comorbid” behaviour pattern (i.e., problematic drug consumption and mental disturbances) is widely spread among opiate addicts. This behaviour pattern does not stand alone but is imbedded in the dynamics of development of the client’s general life situation seen in biographical retrospective as well as in the present context of individual resources and external conditions. The importance of a psychiatric diagnosis under ICD-10, descriptively representing a “disturbed” pattern of behaviour and experience with the help of a number of underlying criteria, cannot be determined clearly in the surveyed persons. (This, of course, does not apply to psychiatric diagnoses in general. In particular, the sort of disturbance accompanying the disorder, as well as onset and duration of certain symptoms, must be considered when examining the status of individual disorders. These, however, are not the subject of the analyses reported here but are considered in terms of the global group formation according to the gravity of the mental disorder.) The expected clear connection between the general ability to act related to the mental disorder and the drug consumption pattern, as well as the addict’s life situation, cannot be ascertained. Rather it is the presently felt disturbance due to mental symptoms or syndromes that are interrelated with the extent of drug consumption, as well as to bodily health and social problems/conflicts, and which thus strengthens the relevance of the “comorbidity hypothesis.” It is not a question of chicken or egg that is at issue here. A parallelism, coincidence, course or causality of various deviant behaviour patterns felt as problematic can be ascertained among many opiate addicts. A treatment, care or guidance plan must consider these connections. Working on the “symptom” of drug consumption or addiction or on the “problem” of social stability will probably only be successful when considering the complex framework of individual behaviour. The sometimes “inadequate provision” for many opiate addicts in contact with drug help institutions already mentioned thus becomes understandable. A complete psychiatric evaluation is not necessary to discover mental symptoms or problems among clients. As an alternative, specific screening questions in the context of an assessment could be used in the course of advice or treatment contacts. Comorbidity then should become part of a more comprehensive therapeutic care programme. Psychiatric diagnostics are necessary only when disorder patterns with a complicated course become apparent during further contact. In these cases, psychologically/psychiatrically trained expertise should be consulted to enhance the chances of an individual treatment success.

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