Inflammatory markers in major depression and melancholia

Journal of Affective Disorders 63 (2001) 93–102 www.elsevier.com / locate / jad

Research report

Inflammatory markers in major depression and melancholia a, a a b b Matthias Rothermundt *, Volker Arolt , Marion Peters , Heike Gutbrodt , Jan Fenker , a b Anette Kersting , Holger Kirchner a

Department of Psychiatry and Psychotherapy, Westfaelische Wilhelms-University, Albert-Schweitzer-Strasse 11, D-48129 Muenster, Germany b Institute of Immunology and Transfusion Medicine, University of Luebeck School of Medicine, Luebeck, Germany Received 18 October 1999; received in revised form 24 December 1999; accepted 29 January 2000

Abstract Background: There is evidence that patients with major depression (MD) also suffer an inflammatory immune reaction. However, the results remain ambiguous. This could be due to the psychiatrically heterogeneous patient samples investigated in many published studies. Since melancholic depression is psychopathologically and possibly etiologically different from non-melancholic MD, we focused on investigating immune parameters in these two subgroups. Methods: 43 in-patients suffering from acute major depression were diagnosed, sub-classified according to DSM IV criteria, and compared to 43 matched healthy controls. Cell counts were determined by morphology, and acute phase proteins [c-reactive protein (CRP), a 2 -macroglobulin (A2M), haptoglobin (HP)] were measured by laser nephelometry. Cytokine production (IL-1b) upon mitogen stimulation was measured by ELISA in a whole blood assay. Results: Non-melancholic patients showed increased monocyte counts and A2M serum concentrations in the acute stage of disease and after 2 and 4 weeks of treatment. Melancholic patients demonstrated a decreased monocyte count upon admission and after 4 weeks of treatment. HP levels and IL-1b production were unchanged in all studied subjects. Limitations: Medication of the patients varied. The differentiation between melancholic and non-melancholic depression was performed clinically and was not performed using any standardized instrument. Conclusion: Melancholic and non-melancholic patients show different immune patterns. This differentiation might clarify immunological findings in MD and point towards etiological factors that are involved in the development of various subtypes of MD.  2001 Elsevier Science B.V. All rights reserved. Keywords: Major depression; Melancholia; Immunology; Cytokines; Acute phase proteins; Monocytes

1. Introduction Alterations in the immune system of patients *Corresponding author. Tel.: 149-251-8352-581; fax: 149251-8356-612. E-mail address: [email protected] (M. Rothermundt).

suffering from major depression (MD) have been reported throughout the last 2 decades. Several studies demonstrated evidence for inflammatory reactions in acute major depression (for review: Maes, 1995). Due to its crucial role in acute inflammatory reactions of the body, the monocyte–macrophage system has received the most attention.

0165-0327 / 01 / $ – see front matter  2001 Elsevier Science B.V. All rights reserved. PII: S0165-0327( 00 )00157-9

94

M. Rothermundt et al. / Journal of Affective Disorders 63 (2001) 93 – 102

During immune responses, monocytes (similarly to macrophages) do not just exert local effects. Cytokines produced by monocytes (e.g. interleukin-1b) exert far-reaching effects on the body. They increase body temperature and stimulate hepatocytes so that acute phase proteins are produced (e.g. C-reactive protein, haptoglobin and a 2 -macroglobulin). These proteins activate the complement system and opsonize exogenous organisms such as bacteria. Several studies have shown that monocyte counts are increased amongst patients suffering from major depression (Maes et al., 1992b, 1994b; Seidel et al., 1996; Castilla-Cortazar et al., 1998). However, other investigations revealed unchanged (Irwin et al., 1987; Darko et al., 1988; Maes et al., 1989, 1993a, 1994a; Anesi et al., 1994) or even decreased (McAdams and Leonard, 1993) monocyte counts in patients with MD compared to healthy controls. Interleukin-1b (IL-1b) is a monokine involved in the early inflammatory immune response. The production of IL-1b upon mitogen stimulation was reported to be increased in patients with minor and major depression (Maes et al., 1991, 1993c). In contrast, Weizman et al. (1994) showed a decreased production of IL-1b in depressed patients. C-reactive protein (CRP) is one of the most frequently measured acute phase proteins in clinical medicine. Several studies reported increased serum levels of CRP in patients suffering from MD (Legros et al., 1985; Seidel et al., 1995; Sluzewska et al., 1996a,b, 1997; Berk et al., 1997), while in other investigations, no differences in CRP serum levels between patients with MD and healthy controls could be found (Joyce et al., 1992; Maes et al., 1992a). Haptoglobin (HP) is the most frequently studied acute phase protein in MD and has provided the most consistent results. Several groups demonstrated increased HP serum levels in MD (Joyce et al., 1992; Maes et al., 1992a,c, 1993a,b, 1994c, 1997c; Song et al., 1994; Seidel et al., 1995). Another acute phase protein, a 2 -macroglobulin (A2M), was found to be significantly higher in patients with acute MD and after 6 weeks of clinical treatment compared to healthy controls (Seidel et al., 1995). Maes et al. (1992a) reported normal A2M in MD with a trend towards lower levels in melancholia. Obviously, there is a lack of consistency in the

responses of the investigated immune parameters. One reason for this might be that the diagnostic group of MD classified according to DSM III-R and DSM IV criteria is simply too heterogeneous. Few researchers have attempted to deal with this problem. Some have tried to determine associations between immune parameters and severity of depression (Maes et al., 1989; Joyce et al., 1992; Maes et al., 1993b, 1994a), or sought and found correlations between psychopathological features and immune function (Maes et al., 1993d). Another approach has been to study immunological changes at different stages during the course of the disease (McAdams and Leonard, 1993; Seidel et al., 1995, 1996). The DSM IV classification category of ‘major depression’ covers different kinds of depression. These subtypes do not just differ quantitatively; they also differ concerning the quality of symptoms. In melancholic depression, the nature of disturbed affect is distinct from that experienced in non-melancholic major depression. Vegetative symptoms are prominent and the circadian rhythm is affected. Since melancholic depression is considered to be the most ‘biological’ form of depression, we wondered whether there might be a distinct immune pattern in this subtype of depression. If so, this discrimination might help to clarify the divergent results reported in earlier studies. Bearing all this in mind, we undertook a study that included subjects suffering from MD either with or without melancholic features and normal controls. The patients were studied in an acute stage of disease and followed-up during clinical improvement after 2 and 4 weeks of treatment. We focused on monocytes, the related monokine IL-1b, and the acute phase proteins, CRP, A2M and HB.

2. Materials and methods

2.1. Patients and controls Forty-three patients (15 men, 28 women) who had been hospitalized in the Department of Psychiatry, ¨ University of Lubeck School of Medicine, and who were suffering from a major depressive episode (DSM-IV 296.2, 296.3; ICD-10 F32, F33), were

M. Rothermundt et al. / Journal of Affective Disorders 63 (2001) 93 – 102

enrolled. They were clinically diagnosed by two experienced psychiatrists according to DSM-IV and ICD-10 criteria. Furthermore, the German edition (Wittchen and Semler, 1990) of the CIDI (Composite International Diagnostic Interview, Robins et al. 1988) was also applied to diagnose the patients. The mean age at the time of the study was 44.45 years (S.D. 9.95 years), and the range was between 27 and 62 years. The control group consisted of 43 age- and sex-matched healthy blood donors (mean age 44.4569.95 years). All subjects gave written informed consent. Upon admission and during the follow-ups, patients and controls underwent a medical history and physical examination. They were screened for acute infectious diseases by measuring body temperature and erythrocyte sedimentation rate. They were free of past physical illnesses (e.g. acute or chronic infections, autoimmune diseases, cancer) and any medication that might have influenced immune function (e.g. corticosteroids, lithium, neuroleptics). Eighteen (41.8%) patients were diagnosed as suffering from a single episode of a major depressive disorder (MD), twelve of whom had MD with moderate severity, and six of whom had severe MD without psychotic features. Twenty-five patients (58.2%) were diagnosed as suffering from a recurrent major depressive disorder, six with moderate severity, and nineteen with severe MD without psychotic features. A subgroup of 22 patients was identified which fulfilled the DSM-IV-criteria for major depression with melancholic features. Six patients (14%) were free of antidepressant medication upon admission, twenty-eight patients (65.1%) were on tricyclic antidepressant drugs (sixteen amitriptylin, nine doxepine, three maprotiline), and nine patients (20.9%) took serotonin reuptake inhibitors (SSRI: one citaloprame, two fluoxetine, two mirtazapine, two paroxetine and two venlafaxine). Twenty-seven patients included in the study were non-smokers while sixteen patients smoked between four and thirty-five cigarettes per day. Investigations took place on the day after hospital admission (t1) as well as after 2 (t2) and 4 (t3) weeks of treatment. The severity of depressive symptoms was rated using the German version of the Hamilton Depression Rating Scale (HDRS) (Hamilton, 1960; Baumann, 1976).

95

The absolute and relative monocyte counts were determined. The cells’ ability to produce the cytokine IL-1b upon mitogen stimulation was investigated. Serum levels of the acute phase proteins HG, CRP and A2M were determined. Monocytes were morphologically counted.

2.2. Whole-blood assay At 8 a.m., heparinized blood was drawn by venous puncture from patients and controls before it was stored (48C) and cultured in a whole-blood assay within 1–2 h according to a previously described technique (Kirchner et al., 1982). In a 5-ml poly¨ sterol tube (Greiner, Nurtingen, Germany), 100 ml of blood was added to 850 ml of Roswell Park Memorial Institute (RPMI) medium (Biochrom, Berlin, Germany) supplemented with 2 mM L-glutamine, 100 U / ml penicillin, and 100 ml / ml streptomycin (Gibco, Karlsruhe, Germany). For the induction of IL-1b, phytohemagglutinin (PHA) (Borroughs Wellcome, Dartford, UK) was added at a final concentration of 5 mg / ml. The blood suspension was incubated at 378C with 95% air–5% CO 2 for 48 h. The supernatants were recovered and kept frozen at 2 808C.

2.3. Determination of IL-1b IL-1b concentrations were determined by an enzyme-linked immunosorbent assay (ELISA) technique. Recombinant cytokines were used as standards. We used ELISA kits from BioSource (Camarillo, USA), according to the manufacturer’s instructions. The intra-assay coefficient of variation was 3.9%. The inter-assay coefficient of variation was 6.8%.

2.4. Determination of serum protein concentrations CRP, HP and A2M concentrations were determined by laser nephelometry (BN 100, Behringwerke, Marburg, Germany). All antisera, controls and standards used for protein measurement were also obtained from Behringwerke. We used a single batch of antiserum for each parameter and included appropriate controls in each run. The intra-assay and

M. Rothermundt et al. / Journal of Affective Disorders 63 (2001) 93 – 102

96

inter-assay coefficients of variation were , 2% and , 5%, respectively.

3. Results The mean score of the HDRS, 21 items version, indicating the severity of depressive symptoms upon admission (t1), was 27 (S.D. 7). After 2 (t2) and 4 weeks (t3) of treatment the scores were 1968 and 1769, indicating that treatment induced a significant clinical improvement of depression (Friedman x 2 5 43.80, P # 0.001). The HDRS scores of the subgroups with or without melancholic features are shown in Table 1. At t1, the MDM patients showed a significantly higher HDRS score (Mann–Whitney U, Z5 22.26, P50.024) than the MDNM patients. After 2 and 4 weeks of treatment, no significant differences between the subgroups could be detected. There were no differences between the absolute and relative monocyte counts of patients suffering from MD and matched healthy controls upon admission (t1), and after 2 (t2) or 4 weeks (t3) of treatment (Table 2). After dividing the whole group of major depression patients into the two subgroups according to the DSM IV criteria for melancholic features, MDNM patients showed significantly high-

2.5. Statistics Due to the non-Gaussian distribution of our data, non-parametric tests were applied for statistical evaluation. The Wilcoxon matched-pairs signedranks test, the Friedman two-way Anova test, the Mann–Whitney U test and the Spearman correlation coefficient were used as provided by the SPSS 8.0 program. We reviewed the data from our previous studies (Seidel et al. 1995, 1996) focusing on the diagnostic classification of the patient sample. All patients included in the sample met the criteria of major depression according to DSM IV criteria. All but two patients suffered from non-melancholic subtype of major depression (MDNM), while only two patients were identified as suffering from major depression with melancholic features (MDM). Table 1 Score of the Hamilton Depression Rating Scale (HDRS) n

t1 c

t2 c

t3 c

Major depression total group

43

Mean 27 S.D. 7 Median 27

Mean 19 a S.D. 8 Median 19

Mean 17 a,b S.D. 9 Median 16

Melancholic depression (MDM)

22

Mean 29 S.D. 7 Median 29

Mean 19 a S.D. 9 Median 22

Mean 19 a S.D. 11 Median 17

Non-melancholic depression (MDNM)

21

Mean 25 S.D. 6 Median 23.5

Mean 19 a S.D. 7 Median 17.5

Mean 16 a,b S.D. 8 Median 14

a

Significantly different from t1 (P#0.001). Significantly different from t2 (P#0.05). c t1: admission; t2: after 2 weeks; t3: after 4 weeks; S.D.5standard deviation. b

Table 2 Monocyte counts in major depression (MD)a

Mean absolute monocyte count / ml Standard deviation Mean relative monocyte count (%) Standard deviation a

t1

t2

t3

Controls

P

484 192 7.19 2.01

520 230 7.48 3.04

526 315 7.97 4.63

452 125 7.92 1.95

NS

t1: upon admission; t2: after 2 weeks of treatment; t3: after 4 weeks; NS: not significant.

NS

M. Rothermundt et al. / Journal of Affective Disorders 63 (2001) 93 – 102

er absolute monocyte counts after 2 and 4 weeks of treatment (t2: 5956252 / ml, Wilcoxon Z5 22.150, P50.032; t3: 6636371 / ml, Wilcoxon Z5 22.189, P50.029) compared to their matched healthy controls (4546127 / ml), whereas upon admission the level of significance was not met (t1: 5646222 / ml, Wilcoxon Z5 21.845, P50.065). The relative monocyte counts in MDNM patients (t1: 8.162.3%, t2: 8.263.3%, t3: 9.765.8%) did not differ from those of the controls (8.061.4%). Patients suffering from melancholic MD (MDM) demonstrated no differences in absolute monocyte counts at any timepoint of the investigation (t1: 4086121 / ml, t2: 4486186 / ml, t3: 3896163 / ml) compared to their matched healthy controls (4496127 / ml). The relative monocyte counts were lower than those of the healthy controls (t1: 6.461.3%, t2: 6.862.7%, t3: 6.262.0%, controls: 7.862.4%), reaching the level of significance upon admission but not during the follow-ups (t1: Wilcoxon Z5 22.451, P50.014; t2: Wilcoxon Z5 20.971, P50.332; t3: Wilcoxon Z5 21.871, P50.061). Comparison of the MDNM and MDM patients revealed significantly higher absolute monocyte counts in patients with MDNM at all time-points of the investigation (Fig. 1). The production of the monokine IL-1b following

97

mitogen stimulation was unchanged in patients with MD (t1: 187.36218.8 pg / ml, t2: 189.56259.2 pg / ml, t3: 203.06249.8 pg / ml) compared to healthy controls (180.56187.6 pg / ml) at all investigation time-points. Differentiation between MDNM and melancholia, smoking habits and antidepressant medication did not yield any significant differences in the production of IL-1b (Fig. 2). Serum levels of CRP in all patients at all timepoints (t1: 0.2260.14 mg / dl, t2: 0.3760.6 mg / dl, t3: 0.2460.16 mg / dl) did not differ from the CRPlevels in matched healthy controls (0.2660.15 mg / dl). In MDM patients, the CRP level was significantly increased after 2 weeks of treatment (t2: Wilcoxon Z5 22.053, P50.04), but was unchanged upon admission and after 4 weeks of treatment (t1: Wilcoxon Z5 20.557, P50.578, t3: Wilcoxon Z5 20.850, P50.395). Patients with MDNM showed significantly lower CRP levels upon admission (Wilcoxon Z5 22.858, P50.004) followed by a normalization after 2 and 4 weeks (Table 3). When comparing the data of MDM and MDNM patients, the MDM patients showed a significantly higher CRP level at t2 (Wilcoxon Z5 22.422, P50.015). The serum levels of the acute phase protein, A2M, in the entire group of MD patients (t1: 175.1654.8 g / l, t2: 180.0653.2 g / l, t3: 180.1658.5 g / l) did not

Fig. 1. Absolute monocyte count in major depression.

M. Rothermundt et al. / Journal of Affective Disorders 63 (2001) 93 – 102

98

Fig. 2. Production of IL-1b in major depression. Table 3 Acute phase proteins in major depression (MD)d MDNM t1 CRP (mg / dl)

0.19 a 60.14

MDM t2

t3

0.21 60.17

0.24 60.16

t1 0.25 60.13

Healthy controls t2 0.54 b,c 60.8

t3 0.25 60.18

0.26 60.15

A2M (g / l)

190.6 b 656.1

194.3 a 657.8

195.0 b 661.4

161.6 652.7

164.7 644.7

164.3 654.2

171.1 640.3

HP (mg / dl)

110.0 653.2

110.3 643.4

100.6 631.5

116.9 639.8

122.8 655.9

113.3 655.7

113.8 648.3

a

Significantly different from healthy controls (P#0.005) Significantly different from healthy controls (P#0.05) c Significantly different from patients with MDNM (P#0.05) d MDM5Major Depression with Melancholic Features; MDNM5Major Depression Non-Melancholic; CRP5C-reactive protein; A2M5 a 2 -macroglobulin; HP5Haptoglobin; t1: on admission; t2: after 2 weeks of treatment; t3: after 4 weeks. b

differ from the healthy controls (171.1640.3 g / l). However, patients with MDNM exhibited significantly higher serum levels than the healthy controls at all investigation time-points (t1: Wilcoxon Z5 2 2.486, P50.013; t2: Wilcoxon Z5 22.902, P5 0.004; t3: Wilcoxon Z5 22.502, P50.012). Melancholic patients on the other hand showed normal A2M levels (Table 3). The smokers among the patients showed significantly higher A2M levels than the non-smokers upon admission (Wilcoxon Z5 2 2.023, P50.043) and after 4 weeks of treatment (Wilcoxon Z5 22.353, P50.019). Neither the whole group of patients with MD nor

the subgroups consisting of patients with MDNM or MDM showed changes in HG serum levels compared to their matched healthy controls (Table 3). Smoking habits did not influence the HP serum levels. No differences in monocyte counts, interleukin-1b production, or acute phase protein serum levels between non-medicated patients, patients on tricyclic antidepressants, or patients treated with selective serotonin reuptake inhibitors (SSRI), were detected. There were no correlations between immune parameters and HDRS scores. No sex-related differences were observed. Patients suffering from recurrent

M. Rothermundt et al. / Journal of Affective Disorders 63 (2001) 93 – 102 Table 4 Comparison of immune patterns in subtypes of major depression a MDM b

Absolute monocyte count Relative monocyte count Production of IL-1b b CRP b A2M b HP b

MDNM b

t1

t2

t3

t1

t2

t3

↔ ↓↓ ↔ ↔ ↔ ↔

↔ ↔ ↔ ↑↑ ↔ ↔

↔ ↓ ↔ ↔ ↔ ↔

↑ ↔ ↔ ↓↓ ↑↑ ↔

↑↑ ↔ ↔ ↔ ↑↑ ↔

↑↑ ↔ ↔ ↔ ↑↑ ↔

Significantly different from healthy controls (P#0.05): ↑↑ or ↓↓; Trend (P#0.1): ↑ or ↓; ↔, no difference. b MDM5Major Depression with Melancholic Features; MDNM5Major Depression Non-Melancholic; IL-1b5 Interleukin-1b; CRP5C-reactive protein; A2M5a-2-macroglobulin; HP5Haptoglobin. t1: upon admission; t2: after 2 weeks of treatment; t3: after 4 weeks. a

depressive episodes did not differ from patients experiencing the first depressive episode concerning the studied immune parameters. In Table 4, the immune patterns in melancholic and non-melancholic depressed patients are summarized.

4. Discussion Many studies on immune functions in patients suffering from major depression have been undertaken over the last decade indicating an inflammatory immune reaction in acute major depression. Even though there is evidence that an inflammatory response is present in some depressed patients, many studies have failed to reproduce these findings or have reported contradictory findings. Advances in the immunological techniques applied have not been able to clarify the discrepancies. Bearing this in mind, there is a need to ask whether a more detailed psychiatric characterization of the patients might help identify immune alterations typical for subgroups of depression. Melancholic depression is not simply a more severe form of non-melancholic depression. It represents a distinct clinical subtype with an episodic rather than a chronic course. Melancholia is characterized by a loss of pleasure in all, or almost all, activities. There is a lack of response to usually

99

pleasurable stimuli and the depressed mood is experienced as a feeling distinct from that experienced after a major loss. There may be a feeling of excessive or inappropriate guilt. In melancholia, depression is regularly worse in the morning, and early morning awakening with depression also occurs. Patients may suffer from marked psychomotor retardation or agitation and significant weight loss. Research results and clinical presentation have led to melancholic depression being considered as the most ‘biological’ form of depression. In this study, a thorough clinical classification of subgroups of major depression was therefore undertaken whereby melancholic features were focused upon. The high scores in the HDRS upon admission demonstrated the severity of depression in the studied subjects. A significant drop after 2 and 4 weeks of treatment shows the extent of the clinical improvement. However, many patients still showed significant psychopathology after 4 weeks of treatment. In future studies, it might be useful to study the same subjects after complete recovery to help determine whether such immune patterns are state or trait markers. The severity of depression did not correlate with any of the investigated immune parameters. It appears that the distinct quality of symptoms in melancholic and non-melancholic depression allows a better association with immune parameters than the degree of symptom severity. Viewing the whole group of studied patients suffering from MD, differences in monocyte counts could not be detected. After dividing the whole group according to the Melancholic Features Specifier of DSM IV, immunological differences between those subgroups could be recognized. The patients with MDNM showed increased absolute monocyte counts as previously reported by Maes et al. (1992b, 1994b), Seidel et al. (1996) and CastillaCortazar et al. (1998). Since appropriate diagnostic data were not given in those studies, one can only speculate that the patient samples investigated might have contained primarily non-melancholic patients. This hypothesis is supported by a reanalysis of our own previous study (Seidel et al., 1996). In that study, all but two subjects suffered from non-melancholic depression. However, in a small sample of eleven male melancholics, Maes et al. (1992b) showed increased monocyte counts while the female

100

M. Rothermundt et al. / Journal of Affective Disorders 63 (2001) 93 – 102

melancholic patients showed unchanged monocyte counts. We were not able to reproduce our earlier finding (Seidel et al., 1996) showing an initial increase in monocyte counts followed by a normalization during treatment. In the study presented here, the monocyte counts in patients with MDNM remained increased throughout the study period. The unchanged production of IL-1b in our study reproduces the findings of Seidel et al. (1995), Anisman et al. (1999) and Natelson et al. (1999). Other groups, however, have demonstrated an increased (Maes et al., 1991, 1993c) or even decreased IL-1b production (Weizman et al., 1994). Even though the production of IL-1b is higher in MDNM than in MDM or healthy controls, the level of significance is not met. This could be due to the large standard deviations in the measurement of IL-1b in all previous studies including our own. During inflammatory reactions, the serum levels of acute phase proteins are expected to be elevated. In our study, only A2M was constantly increased in non-melancholic patients upon admission and after 2 and 4 weeks of treatment. Patients suffering from melancholic depression showed normal A2M levels. We were not able to reproduce the finding of several previous studies whereby increased haptoglobin levels were observed in depressed patients (Joyce et al., 1992; Maes et al., 1992a,c, 1993a,b, 1994c, 1997c; Song et al., 1994; Seidel et al., 1995). This is unlikely to be due to differences in immunological technique, since this study and that published by Seidel et al. (1996) were performed in the same laboratory using the same immunological technique. Maes et al. (1997c) reported that HP levels were elevated only in non-medicated depressed patients and unchanged in medicated patients. In our sample, both medicated and non-medicated patients showed unchanged haptoglobin levels. The power of this study is limited by the fact that only 6 of 43 investigated patients had not received any psychotropic medication upon admission. The influence of antidepressant drugs on immune functions in vivo remains to be characterized in detail, and they are suspected to have at least some immunomodulatory effects. The allocation of patients to non-melancholic and melancholic subgroups was performed independently by two experienced

psychiatrists; unclear cases were excluded, but no standardized instrument was used for allocation. A longer study period would have increased the value of the study when hopefully a more complete clinical response would have occurred. This should be considered for future studies. There is an ongoing discussion concerning how immune alterations in depression might be influenced by stress reactions (Leonard and Song, 1996). Many of the reported findings in depression are also observed in acute or chronic stress. Maes et al. (1997a,b) showed signs of inflammatory reaction in healthy individuals exposed to an acute stressor and in individuals with a high stress perception. If an individual suffers from a severe psychiatric disease such as MD, this in all probability represents a stressful situation. The stress in MD is usually chronic. Hospitalization should be considered as an additional acute stressor. This raises the question whether the immunological changes seen in patients suffering from MD are typical and specific for this disease. Ravindran et al. (1996) demonstrated a comparable immune stimulatory reaction of healthy individuals and major depression patients after exposure to an acute stressor. Unfortunately, inconsistent immunological findings in acute and chronic stress make it difficult to identify immune changes typical for perceived stress. In summary, patients with non-melancholic depression demonstrate increased monocyte counts and A2M serum levels upon admission, and after 2 or 4 weeks of treatment. Other acute phase proteins and the production of IL-1b were not elevated. Patients suffering from MD with melancholic features exhibited normal monocyte counts, acute phase protein serum levels, and production of IL-1b upon mitogen stimulation. We could determine signs of an inflammatory reaction in patients suffering from nonmelancholic major depression, but not in patients with melancholia. This study therefore fails to support the hypothesis that major depression in general is associated with a global inflammatory reaction and that the severity of depressive symptoms is positively correlated with inflammation markers (Maes, 1995). It also remains to be shown whether the signs of inflammation are of pathogenetic significance for non-melancholic depression. To our knowledge, this study is the first demonstrating different immune

M. Rothermundt et al. / Journal of Affective Disorders 63 (2001) 93 – 102

patterns for melancholic and non-melancholic major depression. Future studies should focus on the distinct psychopathological symptoms of melancholic and non-melancholic depression rather than merely the severity of symptoms to confirm or disprove typical immune patterns for each subtype of depression.

Acknowledgements This study was supported by the Volkswagen Foundation (No. I 71 / 998). The authors thank Nicole Heindl for technical assistance and Julian P. Keogh for critically reviewing the text.

References Anesi, A., Franciotta, D., Di Paolo, E., Zardini, E., Melzi d’Eril, G., Zerbi, F., 1994. PHA-stimulated cellular immune function and T-lymphocyte subsets in major depressive disorders. Funct Neurol 9, 17–22. Anisman, H., Ravindran, A.V., Griffiths, J., Merali, Z., 1999. Endocrine and cytokine correlates of major depression and dysthymia with typical or atypical features. Mol Psychiatry 4, 182–188. Baumann, U., 1976. Methodische Untersuchungen zur HamiltonDepression-Skala. Arch. Psychiatrie Nervenkrankheiten 222, 359–375. Berk, M., Wadee, A.A., Kuschke, R.H., O’Neill-Kerr, A., 1997. Acute phase proteins in major depression. J. Psychosom. Res. 43, 529–534. Castilla-Cortazar, I., Castilla, A., Gurpegui, M., 1998. Opioid peptides and immunodysfunction in patients with major depression and anxiety disorders. J. Physiol. Biochem. 54, 203–215. Darko, D.F., Gillin, J.C., Risch, S.C., Bulloch, K., Golshan, S., Tasevska, Z., Hamburger, R.N., 1988. Immune cells and the hypothalamic–pituitary axis in major depression. Psychiatry Res. 25, 173–179. Hamilton, M., 1960. A rating scale for depression. J Neurol Neurosurg Psychiatry 23, 56–62. Irwin, M., Smith, T.L., Gillin, J.C., 1987. Low natural killer cytotoxicity in major depression. Life Sci. 41, 2127–2133. Joyce, P.R.H.C.R., Mulder, R.T., Sellman, J.D., Wilson, D.A., Boswell, D.R., 1992. Elevated levels of acute phase proteins in major depression. Biol. Psychiatry 32, 1035–1041. Kirchner, H., Kleinicke, C., Digel, W., 1982. A whole-blood technique for testing production of human interferon by leukocytes. J. Immunol. Methods 48, 213–219. Legros, S., Mendlewicz, J., Wybran, J., 1985. Immunoglobulins, autoantibodies and other serum protein fractions in psychiatric disorders. Eur. Arch. Psychiatry Clin. Neurosci. 235, 9–11.

101

Leonard, B.E., Song, C., 1996. Stress and the immune system in the etiology of anxiety and depression. Pharmacol. Biochem. Behav. 54, 299–303. Maes, M., Bosmans, E., Suy, E., Minner, B., Raus, J., 1989. Immune cell parameters in severely depressed patients: negative findings. J. Affect. Disord. 17, 121–128. Maes, M., Bosmans, E., Suy, E., DeJonckheere, C., Raus, J., 1991. Depression-related disturbances in mitogen-induced lymphocyte responses and interleukin- 1b and soluble interleukin-2 receptor production. Acta Psychiatr. Scand. 84, 379–386. Maes, M., Scharpe, S., Bosmans, E., Vandewoude, M., Suy, E., Uyttenbroeck, W., Cooreman, W., Vandervorst, C., Raus, J., 1992a. Disturbances in acute phase plasma proteins during melancholia: additional evidence for the presence of an inflammatory process during that illness. Prog. Neuropsychopharmacol. Biol. Psychiatry 16, 501–515. Maes, M., Van der Planken, M., Stevens, W.J., Peeters, D., DeClerck, L.S., Bridts, C.H., Schotte, C., Cosyns, P., 1992b. Leukocytosis, monocytosis and neutrophilia: hallmarks of severe depression. J. Psychiatr Res. 26, 125–134. Maes, M., Scharpe, S., Van Grootel, L., Uyttenbroeck, W., Cooreman, W., Cosyns, P., Suy, B., 1992c. Higher alpha1antitrypsin, haptoglobin, ceruloplasmin and lower retinol binding protein plasma levels during depression: Further evidence for the existence of an inflammatory response during that illness. J. Affect. Disord. 24, 183–192. Maes, M., Scharpe, S., Meltzer, H.Y., Cosyns, P., 1993a. Relationships between increased haptoglobin plasma levels and activation of cell-mediated immunity in depression. Biol. Psychiatry 34, 690–701. Maes, M., Scharpe, S., Meltzer, H.Y., Bosmans, E., Suy, E., Calabrese, J., Cosyns, P., 1993b. Relationships between interleukin-6 activity, acute phase proteins, and function of the hypothalamic-pituitary-adrenal axis in severe depression. Psychiatry Res. 49, 11–27. Maes, M., Bosmans, E., Meltzer, H.Y., Scharpe, S., Suy, E., 1993c. Interleukin-1beta: A putative mediator of HPA axis hyperactivity in major depression? Am. J. Psychiatry 150, 1189–1193. Maes, M., Meltzer, H.Y., Scharpe, S., Cooreman, W., Uyttenbroeck, W., Suy, E., Vandervorst, C., Calabrese, J., Raus, J., Cosyns, P., 1993d. Psychomotor retardation, anorexia, weight loss, sleep disturbances, and loss of energy: psychopathological correlates of hyperhaptoglobinemia during major depression. Psychiatry Res. 47, 229–241. Maes, M., Meltzer, H.Y., Stevens, W., Calabrese, J., Cosyns, P., 1994a. Natural killer cell activity in major depression: relation to circulating natural killer cells. Cellular indices of the immune response, and depressive phenomenology. Prog Neuropsychopharmacol Biol Psychiatry 18, 717–730. Maes, M., Lambrechts, J., Suy, B., Vandervorst, C., Bosmans, E., 1994b. Absolute number and percentage of circulating natural killer. Non-MHC-restricted T cytotoxic, and phagocytic cells in unipolar depression. Neuropsychobiology 29, 157–163. Maes, M., Delanghe, J., Scharpe, S., Meltzer, H.Y., Cosyns, P., Suy, E., Bosmans, E., 1994c. Haptoglobin phenotypes and gene frequencies in unipolar major depression. Am J Psychiatry 151, 112–116.

102

M. Rothermundt et al. / Journal of Affective Disorders 63 (2001) 93 – 102

Maes, M., 1995. Evidence for an immune response in major depression: a review and hypothesis. Prog. Neuropsychopharmacol. Biol. Psychiatry 19, 11–38. Maes, M., Bosmans, E., De Jongh, R., Kenis, G., Vandoolaeghe, E., Neels, H., 1997a. Increased serum IL-6 and IL-1 receptor antagonist concentrations in major depression and treatment resistant depression. Cytokine 9, 853–858. Maes, M., De Meester, I., Verkerk, R., De medts, P., Wauters, A., Vanhoof, G., Vandoolaeghe, E., Neels, H., Scharpe, S., 1997b. Lower serum dipeptidyl peptidase IV activity in treatment resistant major depression: relationships with immune-inflammatory markers. Psychoneuroendocrinology 22, 65–78. Maes, M., Delanghe, J., Ranjan, R., Meltzer, H.Y., Desnyder, R., Cooremans, W., Scharpe, S., 1997c. Acute phase proteins in schizophrenia, mania and major depression: modulation by psychotropic drugs. Psychiatry Res 66, 1–11. McAdams, C., Leonard, B.E., 1993. Neutrophil and monocyte phagocytosis in depressed patients. Prog Neuropsychopharmacol Biol Psychiatry 17, 971–984. Natelson, B.H., Denny, T.N., Zhou, X.D., LaManca, J.J., Ottenweller, J.E., Tiersky, L., DeLuca, J., Gause, W.C., 1999. Is depression associated with immune activation? J. Affect. Disord. 53, 179–184. Ravindran, A.V., Griffiths, J., Merali, Z., Anisman, H., 1996. Variations of lymphocyte subsets associated with stress in depressive populations. Psychoneuroendocrinology 21, 659– 671. Robins, L.N., Wittchen, H.U., Helzer, J.E., Babor, T.F., Burke, J., Farmer, A., Jablenski, A., Pickens, R., Regier, D.A., Sartorius, N., Towle, L.H., 1988. The composite international diagnostic interview. Arch. Gen. Psychiatry 45, 1069–1077.

Seidel, A., Arolt, V., Hunstiger, M., Rink, L., Behnisch, A., Kirchner, H., 1995. Cytokine production and serum proteins in depression. Scand. J. Immunol. 41, 534–538. Seidel, A., Arolt, V., Hunstiger, M., Rink, L., Behnisch, A., Kirchner, H., 1996. Increased CD56 1 natural killer cells and related cytokines in major depression. Clin. Immunol. Immunpathol. 78, 83–85. Sluzewska, A., Rybakowski, J., Bosmans, E., Sobieska, M., Berghmans, R., Maes, M., Wiktorowicz, K., 1996a. Indicators of immune activation in major depression. Psychiatry Res 64, 161–167. Sluzewska, A., Rybakowski, J.K., Sobieska, M., Wiktorowicz, K., 1996b. Concentration and microheterogeneity glycophorms of a-1-acid glycoprotein in major depressive disorder. J. Affect. Disord. 39, 149–155. Sluzewska, A., Sobieska, M., Rybakowski, J.K., 1997. Changes in acute-phase proteins during lithium potentiation of antidepressants in refractory depression. Neuropsychobiology 35, 123– 127. Song, C., Dinan, T., Leonard, B.E., 1994. Changes in immunoglobulin, complement and acute phase protein levels in the depressed patients and normal controls. J Affect Disord 30, 283–288. Weizman, R., Laor, N., Podliszewski, E., Notti, I., Djaldetti, M., Bessler, H., 1994. Cytokine production in major depressed patients before and after clomipramine treatment. Biol Psychiatry 35, 42–47. Wittchen, H.U., Semler, G., 1990. Composite International Diagnostic Interview (CIDI, Version 1.0). Beltz, Weinheim.