Evaluation of subjective treatment satisfaction with antipsychotics in schizophrenia patients

Evaluation of subjective treatment satisfaction with antipsychotics in schizophrenia patients

Available online at www.sciencedirect.com Progress in Neuro Psychopharmacology & Biological Psychiatry 32 (2008) 755 – 760 www.elsevier.com/locate/pn...

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Available online at www.sciencedirect.com

Progress in Neuro Psychopharmacology & Biological Psychiatry 32 (2008) 755 – 760 www.elsevier.com/locate/pnpbp

Evaluation of subjective treatment satisfaction with antipsychotics in schizophrenia patients Midori Fujikawa a,b , Takashi Togo a,⁎, Asuka Yoshimi c , Junichi Fujita d , Munetaka Nomoto d , Atsushi Kamijo a , Toru Amagai a , Hirotake Uchikado b , Omi Katsuse b , Hideki Hosojima e , Yoshihisa Sakura f , Ryo Furusho g , Akira Suda g , Takayuki Yamaguchi h , Taketo Hori a , Ayuko Kamada g , Taizo Kondo g , Michitomo Ito e , Toshinari Odawara g , Yoshio Hirayasu a a

Department of Psychiatry, Yokohama City University, 3-9 Fukuura, Kanazawa-ku Yokohama 236-0004, Japan b Yokohama Maioka Hospital, 3482 Maioka-cho, Totsuka-ku, Yokohama 244-0813, Japan c Washin-Zaka Hospital, 169 Yamate-cho, Naka-ku, Yokohama 231-0862, Japan d Kanagawa Psychiatric Center, 2-5-1 Serigaya, Kounan-ku, Yokohama 233-0006, Japan e Higashi-Kanagawa Clinic, 1-13-12 Nishi-Kanagawa, Kanagawa-ku, Yokohama 221-0822, Japan f Yokohama Minami-Kyosai Hospital, 1-21-1 Mutsuura-Higashi, Kanazawa-ku, Yokohama 236-0037, Japan g Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama 232-0024, Japan h NTT Higashi-Nihon Izu Hospital, 750 Hirai, Kannami-cho, Tagata-gun, Shizuoka 419-0913, Japan Received 20 July 2007; received in revised form 4 December 2007; accepted 5 December 2007 Available online 14 December 2007

Abstract Adherence to antipsychotic treatment is particularly important in the long-term management of schizophrenia and other related psychotic disorders since poor adherence to medication is associated with poor health outcomes. Although the patients’ subjective satisfaction with the medication is crucial for adherence to medication, few studies have examined the relationship between subjective satisfaction with antipsychotics and adherence. In this study, we investigated subjective satisfaction with antipsychotics in patients with schizophrenia by using the Treatment Satisfaction Questionnaire for Medication (TSQM), a self-reporting instrument to assess the major dimensions of patients’ satisfaction with their medication. The subjects included 121 clinically stabilized outpatients who met the following criteria: 1) patients between 20 and 65 years of age, diagnosed with schizophrenia or other psychotic disorders as defined by DSM-IV, 2) patients undergoing oral antipsychotic monotherapy or taking only an antiparkinsonian agent as an adjuvant remedy, and 3) patients who had received a stable dose of an antipsychotic for more than four weeks. Patients were asked to answer the TSQM questions, and their clinical symptoms were also evaluated by the Brief Psychiatric Rating Scale (BPRS). Satisfaction with regard to side-effects ( p = 0.015) and global satisfaction (p = 0.035) were significantly higher in patients taking secondgeneration antipsychotics (SGAs, n = 111) than those taking first-generation antipsychotics (FGAs, n = 10), whereas no significant difference was found between the two groups in clinical symptoms according to BPRS ( p = 0.637) or the Drug-induced Extrapyramidal Symptoms Scale (DIEPSS, p = 0.209). In addition, correlations were not significant between the subjective satisfactions and clinician-rated objective measures of the symptoms. These findings suggest that SGAs have more favorable subjective satisfaction profiles than FGAs in the treatment of schizophrenia.

Abbreviations: BPRS, the Brief Psychiatric Rating Scale; DAI, the Drug Attitude Inventory; DIEPSS, the Drug-Induced Extrapyramidal Symptoms Scale; FGAs, First-generation antipsychotics; SGAs, Second-generation (atypical) antipsychotics; TSQM, the Treatment Satisfaction Questionnaire for Medication. ⁎ Corresponding author. Department of Psychiatry, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan. Tel.: +81 45 787 2667; fax: +81 45 783 2540. E-mail addresses: [email protected] (M. Fujikawa), [email protected] (T. Togo), [email protected] (A. Yoshimi), [email protected] (J. Fujita), [email protected] (M. Nomoto), [email protected] (A. Kamijo), [email protected] (T. Amagai), [email protected] (H. Uchikado), [email protected] (O. Katsuse), [email protected] (H. Hosojima), [email protected] (Y. Sakura), [email protected] (R. Furusho), [email protected] (A. Suda), [email protected] (T. Yamaguchi), [email protected] (T. Hori), [email protected] (A. Kamada), [email protected] (T. Kondo), [email protected] (M. Ito), [email protected] (T. Odawara), [email protected] (Y. Hirayasu). 0278-5846/$ - see front matter © 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.pnpbp.2007.12.002

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Since it is often difficult to detect the difference by a traditional objective assessment of the patients, it is desirable that physicians pay attention to the patients’ subjective satisfaction in conjunction with their own objective clinical assessment. © 2007 Elsevier Inc. All rights reserved. Keywords: Adherence; Schizophrenia; Subjective treatment satisfaction; TSQM

1. Introduction Adherence is a critical issue for long-term antipsychotic treatment in schizophrenia and other related psychotic disorders. Poor adherence to medication is associated with poor health outcomes, such as an increased risk of relapse, rehospitalization, longer hospital admission, repeated emergency department visits, worsening of symptoms, and suicide attempts (Robinson et al., 1999; Kim et al., 2006). During the past decade, the change in terminology from “compliance” to “adherence” has served to promote the idea that treatment by medication should be a collaborative effort between physician and patient (Velligan et al., 2006). In contrast to the paternalistic system of “compliance,” in which the physician takes the major role in deciding on treatment, shared decision-making means that the physician communicates information about the illness, treatment options, and recommendations to the patient. Also, psychosocial intervention, professional psychoeducation, and peer-to-peer or family-to-family intervention have the potential to improve adherence to medication in cases of schizophrenia (Leucht and Heres, 2006). From the perspective of shared decision-making, the patient’s subjective satisfaction with the medication is crucial for medication adherence (Atkinson et al., 2004; Taira et al. 2006). However, few studies have examined the relationship between subjective satisfaction with antipsychotics and adherence. One of the popular assessment scales to evaluate subjective responses to medication with antipsychotics is the Drug Attitude Inventory (DAI) (Hogan et al., 1983). This scale was developed to measure subjective responses to medication in an effort to obtain a more complete understanding of factors influencing medication “compliance” in schizophrenia patients. While studies have revealed a high correlation between medication compliance and treatment outcome by using DAI (Freudenreich et al., 2004; Adewuya et al., 2006; Taira et al., 2006), other studies have also identified several deficiencies in the DAI. The arbitrary classification of subjects as “compliers” and “non-compliers” may not acknowledge the complex nature of compliance, which is not an all-or-none phenomenon (Thompson et al., 2000). While the DAI was developed to obtain good “compliance,” it is not suitable for assessing the subjective feelings towards medication that are crucial in shared decision-making in an effort to establish “adherence.” Also, DAI focuses on rather global aspects of medication benefits, not medication-specific effects or the sideeffects which are important for “adherence” in patients taking a particular medicine (Freudenreich et al., 2004). The Treatment Satisfaction Questionnaire for Medication (TSQM), developed by Atkinson et al. (2004) is a psychometrically sound and valid measure of the major dimensions of patients’ satisfaction with medication, which is crucial for evaluating “adherence”. Although patients’ satisfaction with

their medication is considered to be more significant in shared decision-making during maintenance therapy for a clinically stabilized condition than acute therapy in patients with schizophrenia, the general nature of the TSQM provides a way of evaluating and comparing patients’ satisfaction with various types and forms of medications. Moreover, the TSQM may contribute to our understanding of patients’ medication-related decisions and behaviors (Atkinson et al., 2004). The TSQM is a self-reporting instrument consisting of 11 items that make up three specific scales (effectiveness, sideeffects, convenience) and three items that make up one global satisfaction scale. Each item is scored using either a 5-point or 7-point scale, and the scale scores are transformed into scores ranging from 0 to 100 on each specific scale; higher scores reflect greater satisfaction. In this study, subjective satisfaction with antipsychotics was investigated in patients with schizophrenia, by using the TSQM. We hypothesized that patients’ satisfaction may depend on their medication, which would affect their “adherence.” We also investigated the relationship between subjective satisfaction with their medication as assessed by the TSQM and their clinical (psychiatric and extrapyramidal) symptoms. 2. Methods 2.1. Subjects This study was performed at two university hospitals, five psychiatric hospitals and an outpatient clinic in Japan (Yokohama City University Hospital, Yokohama City University Medical Center, Yokohama Maioka Hospital, WashinZaka Hospital, Kanagawa Psychiatric Center, Yokohama Minami-Kyosai Hospital, NTT Higashi-Nihon Izu Hospital, and Higashi-Kanagawa Clinic). In compliance with therapyconcurrent naturalistic study design, patients were recruited at their respective outpatient departments. Patients who met the following criteria were recruited and included in this study: 1) patients between 20 and 65 years of age, diagnosed with ‘schizophrenia or other psychotic disorders’ as defined by DSM-IV (American Psychiatric Association, 1994), 2) patients undergoing oral antipsychotic monotherapy or taking only an antiparkinsonian agent (biperiden, trihexyphenidyl) as an adjuvant remedy (patients receiving benzodiazepines, antidepressants, mood stabilizers or sedating antihistamine were excluded), and 3) patients who had received a stable dose of an antipsychotic for more than four weeks. The diagnosis was initially made by the treating psychiatrist and then by the authors, who all have more than 5 years of experience in the treatment of schizophrenia according to the DSM-IV criteria. This study was approved by the Human Subjects Review

M. Fujikawa et al. / Progress in Neuro Psychopharmacology & Biological Psychiatry 32 (2008) 755–760 Table 1 Patient background and subjective satisfaction with FGAs and SGAs

Number Age (years) Gender Male/female Age at onset (years) Duration of illness (years) Number of hospitalizations Number of medications per day CP-equivalent daily dose (mg) TSQM Effectiveness Side-effects Convenience Global satisfaction BPRS DIEPSS

t or χ2 value

FGAs

SGAs

10 48.1 ± 12.1

111 40.7 ± 12.9 t = 1.714

1/9 28.7 ± 10.3 19.4 ± 13.9 1.2 ± 1.5 1.9 ± 0.9

68/43 30.1 ± 10.9 10.6 ± 9.2 1.7 ± 1.9 1.3 ± 0.6

selves when visiting the outpatient clinic. Clinical symptoms were evaluated by the attending doctor at the same time. P value

2.3. Data analysis 0.084

χ = 9.836 t = − 0.398 t = 1.944 t = − 0.113 t = 1.973

0.002⁎ 0.704 0.081 0.911 0.077

t = − 1.825 t = − 2.468 t = 0.177 t = − 2.302 t = − 0.473 t = 1.264

0.07 0.015⁎ 0.86 0.035⁎ 0.637 0.209

2

240.3 ± 128.4 Not applicable 58.5 ± 10.7 69.4 ± 31.0 79.4 ± 14.3 55.6 ± 10.3 22.9 ± 4.8 1.5 ± 1.6

67.0 ± 14.3 87.7 ± 21.6 78.5 ± 15.9 64.3 ± 20.2 24.0 ± 7.4 0.9 ± 1.5

757

⁎P b 0.05.

Committee of each hospital and clinic, and each patient provided written informed consent for participation after the procedures had been fully explained. 2.2. Assessments and measures A Japanese version of the TSQM was translated from the original English version (TSQM v 1.4.) by the authors for the present study. The Japanese version was then back-translated to English by a native English speaker. The validity of the translation was confirmed by the developer of the scale, Quintiles (San Francisco, CA, USA), and the Japanese version was approved for use in this study. Psychiatric symptoms were evaluated with the Brief Psychiatric Rating Scale (BPRS; Overall and Gorham, 1962), while the Drug-induced Extrapyramidal Symptoms Scale (DIEPSS; Inada et al., 2003) was used to evaluate drug-induced extrapyramidal symptoms. Patients were asked to answer the TSQM questions by them-

Second-generation (atypical) antipsychotics (SGAs) were compared with first-generation antipsychotics (FGAs) with respect to each of the four TSQM items (effectiveness, sideeffects, convenience and global satisfaction), total BPRS score and total DIEPSS score, by unpaired (two-sample) t-tests. Prior to the unpaired t-test, Levene’s test was used to assess the equality of variance in the two samples. Student’s t-test was used if the variance of the two samples was assumed to be equal, while Welch's t-test was used with two samples of unequal variance. Differences in gender between the two groups were analyzed by the chi-square method. One-way analyses of variance (ANOVA) were used to compare four SGAs (risperidone, olanzapine, quetiapine and perospirone) with respect to each of the four scales of the TSQM, the total BPRS score and the total DIEPSS score. Also, patients with and without an antiparkinsonian agent were compared by an unpaired t-test as described above for each of the four TSQM items, the total BPRS score and the total DIEPSS score, to reveal the effects of concomitant use of antiparkinsonians on their treatment satisfaction. The correlations between each TSQM score and clinical variables (total BPRS score and total DIEPSS) were analyzed by using Spearman’s rank-correlation coefficient. The correlations were also examined in the same way between the convenience/global satisfaction items of the TSQM and the number of medications taken per day. The data was analyzed using SPSS for Windows Version 11.0J (SPSS Inc., Chicago, USA), and significance levels were set at p b 0.05. 3. Results 3.1. Baseline characteristics of patients (Table 1) A total of 121 patients (53 women and 68 men), including 117 patients with schizophrenia, three patients with schizophreniform disorder and one patient with delusional disorder,

Table 2 Patient background and subjective satisfaction with each SGA

N Age (years) Age at onset (years) Duration of illness (years) Number of hospitalizations Average daily number of medications Average daily dose (mg) TSQM Effectiveness Side-effects Convenience Global satisfaction BPRS DIEPSS ⁎P b 0.05.

Risperidone

Olanzapine

Quetiapine

Perospirone

F value

P value

37 43.6 ± 13.8 31.9 ± 12.1 11.8 ± 10.4 1.0 ± 1.2 1.4 ± 0.6 2.5 ± 2.0

48 37.9 ± 11.1 28.3 ± 10.4 9.6 ± 8.4 1.8 ± 2.6 1.0 ± 0.2 9.1 ± 4.6

6 35.6 ± 17.1 26.6 ± 10.8 9.0 ± 13.4 0.9 ± 0.4 2.4 ± 0.5 429.2 ± 254.1

20 43.9 ± 12.8 32.2 ± 9.3 11.7 ± 7.4 0.5 ± 0.8 1.7 ± 0.7 15.3 ± 7.2

2.208 1.240 0.545 2.809 21.874

0.091 0.299 0.653 0.043⁎ b0.001⁎

69.8 ± 14.9 89.7 ± 20.2 82.1 ± 15.0 68.7 ± 23.5 24.0 ± 6.2 0.81 ± 1.20

63.2 ± 14.2 87.6 ± 22.9 78.5 ± 14.5 62.8 ± 18.3 24.2 ± 8.0 1.04 ± 1.84

64.8 ± 14.3 84.4 ± 24.9 66.7 ± 16.7 53.6 ± 25.9 22.5 ± 4.6 0.50 ± 1.22

71.4 ± 12.1 84.7 ± 21.8 75.3 ± 19.5 63.2 ± 15.1 24.2 ± 8.2 0.65 ± 1.27

2.548 0.525 1.635 1.095 0.201 0.509

0.060 0.666 0.186 0.354 0.896 0.677

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participated in this study. The mean age of the patients was 41.3 ± 12.8 years [mean ± SD], while the mean age at onset was 30.0 ± 10.8 years. The mean number of prior hospitalizations was 1.3 ± 1.9 times. While ten patients had received FGAs (haloperidol = 7, 2.1 ± 0.9 mg/day; bromperidol = 2, 3 mg/day and 4 mg/day; timiperone = 1 and 2 mg/day), 111 patients had received SGAs (risperidone = 37, olanzapine = 48, quetiapine = 6, perospirone = 20). The mean BPRS score of the patients was 23.9 ± 7.2, while the mean DIEPSS score was 0.9 ± 1.5, suggesting that the subjects of this study were clinically stabilized schizophrenia patients with fewer extrapyramidal symptoms than expected. 3.2. Subjective satisfaction with medication (Tables 1, 2 and 3) The baseline characteristics and subjective satisfaction of the patients treated with FGAs and SGAs are shown in Table 1 While gender was not balanced between the two groups, there was no other significant difference in the clinic background, including age at the evaluation point, age of onset, number of prior hospitalizations, number of medications taken per day, total BPRS score or total DIEPSS score. Satisfaction with regard to side-effects was significantly higher among patients taking SGAs than among those taking FGAs, indicating a favorable profile for SGAs in terms of side-effects. Also, global satisfaction was significantly higher with SGAs than with FGAs. Although satisfaction with effectiveness among those taking SGAs tended to be higher than among those taking FGAs, the difference was not significant. No significant differences were observed between the two groups in satisfaction with convenience. TSQM, BPRS and DIEPSS scores were compared among SGAs and are summarized in Table 2. Although some differences were found in the clinical background among the four groups taking each SGA, no significant differences were found with respect to any of the four scales of the TSQM, the total BPRS score or total DIEPSS score. Patients with and without an antiparkinsonian agent were compared for each of the four scales of the TSQM, the total BPRS score and the total DIEPSS score, to reveal the effects of concomitant use of antiparkinsonians on their treatment satisfaction. However, concomitant use of antiparkinsonian agents did not affect any of the four scales of the TSQM, the total BPRS score or the total DIEPSS score (data not shown).

Table 3 Correlation between TSQM scores and clinical parameters

TSQM (effectiveness)—BPRS TSQM (global satisfaction)—BPRS TSQM (side-effects)—DIEPSS TSQM (global satisfaction)—DIEPSS TSQM (convenience)—Number of medications per day TSQM (global satisfaction)—Number of medications per day ⁎P b 0.05.

r value

P value

− 0.236 − 0.201 0.009 0.018 − 0.126 − 0.151

0.009⁎ 0.270 0.924 0.849 0.169 0.098

Since we hypothesized that the total BPRS score, total DIEPSS score and number of medications taken per day may affect not only the satisfaction with effectiveness, side-effects and convenience, but also the global satisfaction, the correlations were examined and are summarized in Table 3. Whereas the P value of the correlation between TSQM effectiveness and BPRS was 0.009, the r-square value was far lower than 0.5, indicating that the associations are not clinically relevant. The correlations between the other parameters were not significant. 4. Discussion Claims of superiority for SGAs in terms of the treatment of negative symptoms, cognitive enhancement, fewer extrapyramidal symptoms, and tolerability have led to a general shift away from FGAs in the treatment of schizophrenia. Compared with patients receiving FGAs, those receiving SGAs are reported to be significantly less likely to require a switch in medication and to use concomitant anticholinergic and anxiolytic medications (Menzin et al., 2003). Treatment with SGAs increased the likelihood of complete remission, compared to FGAs (Lambert et al, 2006). From the perspective of medication adherence, some reports have shown that SGAs have a more favorable adverse-effect profile and are associated with better adherence behavior (Dolder et al., 2002). In contrast, some other reports have contested the validity of the claims of the superiority of SGAs. Jones et al. (2006) reported that there is no disadvantage in terms of quality of life (QoL), symptoms, or associated costs of care in using FGAs rather than nonclozapine SGAs. Loffler et al. (2003) reported that even though patientreported non-compliance was mainly explained by the negative side-effects of medication, there were no significant differences between the patients receiving FGAs and SGAs in the subjective reasons that patients gave as to why they were willing or reluctant to take their medication. Diaz et al. (2004) also found no significant difference in adherence between the combined groups of FGAs and SGAs. Overall, while reports have revealed the advantage of SGAs in terms of tolerability, the superiority of SGAs in terms of adherence is still controversial. One of the explanations for the conflicting results with regard to adherence may be differences in evaluation method. Since medication adherence is considered to be affected by multiple factors involving patients, physicians, drugs and the circumstances of the patients, adherence needs to be evaluated in terms of each factor. In the present study, we used the TSQM to investigate subjective satisfaction with antipsychotic medication in patients with schizophrenia, which is a crucial component in evaluating adherence. Our results indicate that satisfaction with regard to side-effects was significantly higher with SGAs than with FGAs. Nevertheless, this satisfaction was not associated with the severity of extrapyramidal symptoms evaluated by DIEPSS or concomitant medication with an antiparkinsonian agent. These results suggest that the severity of clinician-rated extrapyramidal symptoms is not crucial for subjective satisfaction with regard to side-effects, at least in clinically stabilized patients with schizophrenia undergoing antipsychotic monotherapy. Since the

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TSQM questionnaire consists of rather subjective impressions of physical and mental ability or function affected by antipsychotics, such subtle subjective feelings may affect the discrepancy. Also, a higher level of global satisfaction was identified in patients taking SGAs than in those taking FGAs. Nevertheless, this was not associated with the severity of psychotic symptoms evaluated by BPRS or the severity of extrapyramidal symptoms evaluated by DIEPSS. It is possible that subjective satisfaction with regard to the above-described side-effects has an effect on global satisfaction with the medication. On the other hand, no significant differences were observed in the subjective satisfaction with effectiveness and convenience between those taking FGAs and those taking SGAs. Interestingly, Voruganti et al. (2000) reported that clinically stabilized schizophrenic patients receiving SGAs have more positive subjective responses and more favorable attitudes toward their treatment than those receiving FGAs, although these perceived benefits were not reflected in the clinician-rated (objective) measures, which is consistent with our results. Putting these findings together, patients taking SGAs seem to have higher treatment satisfaction than those taking FGAs based on the subjective evaluation, which is difficult to detect by traditional objective assessments of the patients. The patient’s subjective satisfaction with the medication is crucial from the perspective of medication adherence as well as subjective well-being and QoL (Atkinson et al., 2004; Taira et al. 2006). Our results suggest that SGAs are favorable in terms of subjective treatment satisfaction, possibly leading to better medication adherence. In the recent publications, continual treatment with antipsychotics has been reported to lead to an improvement in QoL, an important therapeutic aim of the patients (Wehmeier et al., 2007a b). Also, compliance with antipsychotic medication has shown to be strongly associated with subjective well-being (Karow et al., 2007). Taking these findings together, our results indicate that SGAs may be beneficial for QoL as well as the subjective well-being of patients suffering from schizophrenia as a result of better medication adherence and higher subjective satisfaction. While this study provides unique information allowing for an assessment of subjective treatment satisfaction with antipsychotics, there are several methodological limitations as this was a cross-sectional therapy-concurrent naturalistic study carried out in multiple centers. Firstly, the number of patients taking each drug was biased and the sample size for some drugs was small, in particular those taking FGAs. The proportion of patients treated by monotherapy with FGAs and SGAs appears to reflect current patterns of use seen in clinical practice in Japan. In fact, clinically stabilized patients undergoing monotherapy with FGAs have had their medication switched to SGAs in the past decade, and those receiving FGAs are now more likely to receive concomitant medications due to the severity of the condition. Secondly, the subjects of this study were not patients receiving antipsychotic monotherapy in the strict sense, and some of the patients received concomitant antiparkinsonians. Although this study could not detect the effect of antiparkinsonians on items of subjective satisfaction, it is possible that this concomitant medication biased some outcomes.

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5. Conclusion Subjective satisfaction with antipsychotics was investigated in patients with schizophrenia by using the TSQM questionnaire. The findings revealed that patients taking SGAs have more favorable subjective satisfaction, particularly in terms of side-effects and global satisfaction, than those taking FGAs. Since it was difficult to detect the difference by a traditional objective assessment of the patients, it is desirable for physicians to pay attention to subjective satisfaction in addition to their objective clinical assessment. Pending further studies with a larger sample size, such an approach to the patients could lead to a better adherence to medication and improved therapeutic strategies for schizophrenia. References Adewuya AO, Ola BA, Mosaku SK, Fatoye FO, Eegunranti AB. Attitude towards antipsychotics among out-patients with schizophrenia in Nigeria. Acta Psychiatr Scand 2006;113:207–11. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorder. 4th ed. Washington, DC: American Psychiatric Association; 1994. Atkinson MJ, Sinha A, Hass SL, Colman SS, Kumar RN, Brod M, et al. Validation of a general measure of treatment satisfaction, the Treatment Satisfaction Questionnaire for Medication (TSQM), using a national panel study of chronic disease. Health and Quality of Life Outcomes 2004;26(2):12. Diaz E, Neuse E, Sullivan MC, Pearsall HR, Woods SW. Adherence to conventional and atypical antipsychotics after hospital discharge. J Clin Psychiatry 2004;65:354–60. Dolder CR, Lacro JP, Dunn LB, Jeste DV. Antipsychotic medication adherence: is there a difference between typical and atypical agents. Am J Psychiatry 2002;159:103–8. Freudenreich O, Cather C, Evins AE, Henderson DC, Goff DC. Attitudes of schizophrenia outpatients toward psychiatric medications: relationship to clinical variables and insight. J Clin Psychiatry 2004;65:1372–6. Hogan TP, Awad AG, Eastwood R. A self-report scale predictive of drug compliance in schizophrenics: reliability and discriminative validity. Psychol Med 1983;13:177–83. Inada T, Beasley Jr CM, Tanaka Y, Walker DJ. Extrapyramidal symptom profiles assessed with the Drug-induced Extrapyramidal Symptom Scale: comparison with Western scales in the clinical double-blind studies of schizophrenic patients treated with either olanzapine or haloperidol. Int Clin Psychopharmacol 2003;18:39–48. Jones PB, Barnes TR, Davies L, Dunn G, Lloyd H, Hayhurst KP, et al. Randomized controlled trial of the effect on quality of life of second- vs firstgeneration antipsychotic drugs in schizophrenia: Cost Utility of the Latest Antipsychotic Drugs in Schizophrenia Study (CUtLASS 1). Arch Gen Psychiatry 2006;63:1079–87. Karow A, Czekalla J, Dittmann RW, Schacht A, Wagner T, Lambert M, et al. Association of subjective well-being, symptoms, and side effects with compliance after 12 months of treatment in schizophrenia. J Clin Psychiatry 2007;68:75–80. Kim SW, Shin IS, Kim JM, Yang SJ, Shin SJ, Yoon JS. Association between attitude toward medication and neurocognitive function in schizophrenia. Clin Neuropharmacol 2006;29:197–205. Lambert M, Schimmelmann BG, Naber D, Schacht A, Karow A, Wagner T, et al. Prediction of remission as a combination of symptomatic and functional remission and adequate subjective well-being in 2960 patients with schizophrenia. J Clin Psychiatry 2006;67:1690–7. Leucht S, Heres S. Epidemiology, clinical consequences, and psychosocial treatment of nonadherence in schizophrenia. J Clin Psychiatry 2006;67(Suppl 5):3–8. Loffler W, Kilian R, Toumi M, Angermeyer MC. Schizophrenic patients' subjective reasons for compliance and noncompliance with neuroleptic treatment. Pharmacopsychiatry 2003;36:105–12.

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