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Primary Care Companion to The Journal of Clinical Psychiatry logoLink to Primary Care Companion to The Journal of Clinical Psychiatry
. 2007;9(2):122–128. doi: 10.4088/pcc.v09n0206

The 3-Year Clinical and Functional Course of Schizophrenia Among Individuals With and Without Diabetes at Study Entry

Haya Ascher-Svanum 1, Baojin Zhu 1, Frank R Ernst 1, Douglas E Faries 1, Jennie G Jacobson 1, Caroline C Doebbeling 1,✉
PMCID: PMC1896295  PMID: 17607334

Abstract

Objective: This prospective observational study compared the 3-year clinical and functional course of schizophrenia among individuals with and without diabetes at study entry.

Method: Data were drawn from a large, 3-year, multisite, prospective, naturalistic study of treatment for schizophrenia-related disorders. The study was conducted in the United States between July 1997 and September 2003 and represented treatment practices in diverse systems of care. Participants were diagnosed with schizophrenia or schizoaffective or schizophreniform disorders based on DSM-IV criteria. Clinical and functional outcomes were assessed at study enrollment and at 12-month intervals using standard psychiatric measures, medical records, and a validated patient-reported questionnaire. Diabetes status was determined by participant interview at enrollment. Statistical analyses used mixed models with repeated measures.

Results: Of 594 participants queried about comorbid medical conditions at enrollment, 76 (12.8%) reported having diabetes. Other comor-bid conditions were reported by 79% of the diabetes group (N = 60) and 50% of the nondiabetes group (N = 259). Across the 3-year study, participants with diabetes differed significantly from participants without diabetes on 2 of 36 outcome measures: more contacts with nonpsychiatrist physicians (p < .001) and poorer physical health (p = .015). Groups did not differ significantly on mental health symptomatology, mental health resource utilization, legal and safety issues, substance use, productivity, activities and relationships, or quality of life.

Conclusions: In this 3-year, prospective, naturalistic study, the course of schizophrenia did not differ significantly between participants with and without diabetes, although persons with diabetes did have poorer physical health and more contacts with nonpsychiatrist physicians. Findings highlight the need for better medical treatment for people with schizophrenia, both with and without comorbid diabetes.

Comorbid medical conditions are common among people with serious mental illness1,2 and particularly among people with schizophrenia, who have an increased prevalence of chronic medical conditions such as diabetes mellitus,3,4 chronic respiratory problems,5 cardiovascular disease,6,7 hepatitis B,8 and HIV disease.8 Among these chronic medical conditions, diabetes mellitus has received the most attention to date because some studies suggest that treatment with antipsychotics may increase the risk of diabetes in patients with schizophrenia.9–11

Although comorbid medical conditions appear to exacerbate the psychiatric status of the chronically and severely mentally ill12 and to influence prescribing patterns for antipsychotic medications,13 little is known about how 2 chronic diseases, such as schizophrenia and diabetes, impact one another. Dixon and colleagues14 assessed the impact of chronic mental illness on the management of diabetes, and compared glycosylated hemoglobin levels (HbA1c) in people with diabetes who did or did not have serious mental illness. People with diabetes and schizophrenia had significantly lower (better) levels of HbA1c, although both groups had mean levels above the 7% recommended by the American Diabetes Association. Dixon and colleagues14 concluded that people with schizophrenia were not specifically disadvantaged in their glucose control. Although these findings suggest that schizophrenia may not adversely impact the management of diabetes, it is currently unclear whether diabetes may adversely impact the long-term course of schizophrenia.

To help address this gap and extend previous findings, the present post hoc analysis compares the long-term course of schizophrenia between people with and without diabetes at study enrollment. Using data from a large, prospective, naturalistic, multisite, 3-year study of individuals treated in the United States for schizophrenia-spectrum disorders,15,16 we compared clinical and functional outcomes associated with schizophrenia between participants who reported having diabetes at enrollment and participants who reported not having a diagnosis of diabetes. Because diabetes, a chronic and burdensome medical condition, is associated with increased prevalence of depression17 and with reduced quality of life in the general population,18 we hypothesized that comorbid diabetes would adversely impact clinical and functional outcomes during the 3-year study period. Specifically, we hypothesized that across the 3 years, participants with diabetes at study enrollment would experience more severe psychotic and depressive symptoms, poorer levels of functioning, poorer quality of life, and higher rates of acute psychiatric care such as hospitalization and emergency psychiatric services. We also expected diabetic participants to have a poorer level of physical health and more contacts with nonpsychiatrist physicians to help address their special medical needs.

METHOD

Data Source

This study used data from the United States Schizophrenia Care and Assessment Program (US-SCAP),15,16,19–22 a large (N = 2327), naturalistic, 3-year, prospective, multi-site study conducted between July 1997 and September 2003 and funded by Eli Lilly and Co. The goal of US-SCAP was to understand the treatment for schizophrenia-spectrum disorders in usual care settings. Participants were diagnosed with schizophrenia or schizoaffective or schizophreniform disorders based on DSM-IV criteria and were at least 18 years of age. Participants were excluded if they were unable to provide informed consent or had participated in a clinical drug trial within 30 days prior to enrollment. Approximately 400 participants were enrolled at each of the study's 6 regional sites (California, Colorado, Connecticut, Florida, Maryland, and North Carolina) and represented treatment in diverse systems of care, including community mental health centers, university health care systems, the Department of Veterans Affairs (VA) Health Services, and community and state hospitals. Institutional Review Board (IRB) approval was received at each regional site, and informed consent was received from all participants. Further details about US-SCAP are available elsewhere.15,16

Initial design of US-SCAP did not capture information on participants' diabetes status or other comorbid medical conditions. Beginning in 2000, a query concerning medical conditions was added to the standard screening interview for all subsequently enrolled participants. As a result, enrollment information regarding diabetes was available for 594 US-SCAP participants.

Measures

The presence or absence of diabetes was assessed at enrollment by trained research examiners, who administered a standard structured questionnaire that included questions on medical history. Participants reporting a physician diagnosis of diabetes were defined as having diabetes at study enrollment (DM group), and those who reported not having a physician diagnosis of diabetes were defined as not having diabetes at study enrollment (non-DM group). No other information was collected regarding participants' diabetes (e.g., type of diabetes, duration, glucose blood level, use of antidiabetic agents). Participants were also queried about additional comorbid medical conditions, including hypertension, asthma and respiratory problems, stroke, heart attack, other heart conditions, vascular problems, arthritis, cancer, kidney/renal problems, and “other.” Patient-reported questionnaires have been demonstrated to be a valid method of collecting information about medical comorbidities in the general population.23

Participants with and without diabetes at study enrollment were compared on measures of psychiatric symptoms, psychiatric resource utilization, legal and safety issues, substance use, productivity, activities and relationships, and quality of life. These clinical and functional domains were assessed with 36 variables using 6 instruments that were administered at enrollment and at 12-month intervals thereafter. These instruments were (1) the Positive and Negative Syndrome Scale (PANSS),24 providing total score and subscale scores for positive symptoms, negative symptoms, and general psychopathology; (2) the Montgomery-Asberg Depression Rating Scale (MADRS)25; (3) the Quality of Life Scale26 and its 4 domains: interpersonal role, instrumental (“occupational”), intrapsychic foundations (“motivational”), and common object and activities (“common activities”); (4) the Global Assessment of Functioning scale27; (5) participants' medical records, which systematically assessed mental health resource utilization for each previous 6-month interval and provided information on psychiatric medications, psychiatric hospitalizations, and use of emergency rooms; and (6) the SCAP Health Questionnaire (SCAP-HQ),28 a 102-item, patient-reported measure developed and validated for the US-SCAP study. SCAP-HQ items were drawn from existing measures, such as Lehman's Brief Quality of Life Interview29 and the Medical Outcomes Study 12-Item Short-Form Health Survey (SF-12).30 The psychometric properties of the SCAP-HQ were found to be acceptable for application to large-scale studies in routine care based on a study of its internal consistency, convergent validity, test-retest reliability, and responsiveness to change.28

The SCAP-HQ provided information about legal and safety issues (violent behaviors, arrested/jailed, victimized, suicidal thinking, and suicidal attempts), substance use (alcohol, illicit drugs), productivity (work for pay, number of days worked, any productive activity), activities (daily and leisure activities), relationships (family relationships and frequency of social interactions), and quality of life (mental health as assessed by the SF-12, physical health as assessed by the SF-12, general life satisfaction, independent housing, and medication adherence). The SCAP-HQ also provided information on participants' use of emergency psychiatric services and contacts with nonpsychiatric physicians.

Statistical Analysis

Comparisons between the DM and non-DM groups on sociodemographic and clinical characteristics at enrollment were made using χ2 tests for categorical variables and t tests for continuous variables. Mixed model with repeated measures31 was used to test for group differences in mean scores across the 3-year study period in each of the continuous outcome measures, whereas generalized estimating equations32 were used for the binary variables. Age, gender, marital status, and ethnicity were included in the models as adjusting variables in order to reduce bias due to differences between the 2 comparative groups in baseline sociodemographics. There were no adjustments for additional variables, because the purpose of these analyses was to assess differences in outcomes for patients with and without diabetes; these analyses were not intended to assess any kind of causal effect. All differences of effects were tested at a 2-sided α level of .05. Because our analyses included 36 comparisons, and a few may be statistically significant by chance, we opted to report the findings with and without Bonferroni correction for multiple comparisons (threshold: .05 / 36 = .0014).

RESULTS

Of the 594 participants queried about comorbid medical conditions at enrollment, 76 (12.8%) reported a physician diagnosis of diabetes (DM group), and 518 (87.2%) reported not having been diagnosed with diabetes (non-DM group). The DM group was older, less likely to be single or male, and less likely to lack health insurance (Table 1). Compared with the non-DM group, the DM group had a significantly higher prevalence of hypertension (63.2% vs. 24.7%), kidney dysfunction (12.0% vs. 5.5%), and heart conditions other than heart attack (17.1% vs. 9.2%) (Table 1). There were no significant differences between the groups in use of psychiatric medications during the 6 months prior to enrollment (Table 1). The rate of study attrition (48 participants [63.2%] for the DM group and 376 participants [72.6%] for the non-DM group) was not significantly different across the 3-year period (p = .089). In addition, there were no significant differences in mortality rates between the groups throughout the 3-year study (2 participants [2.6%] in the DM group and 19 participants [3.7%] in the non-DM group, p = .648).

Table 1.

Characteristics at Study Enrollment of Participants With and Without Diabetesa

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At enrollment, there were statistically significant differences between DM and non-DM participants on 9 of the 36 outcome measures examined (Table 2). The DM group had significantly lower PANSS positive scores, more contacts with nonpsychiatrist physicians, and lower likelihood of having a psychiatric hospitalization in the 6 months prior to enrollment. They were less likely to use alcohol or any illicit substance and had fewer paid working days, less frequent social interactions, and poorer physical health. The DM participants reported, however, greater general life satisfaction compared with non-DM participants.

Table 2.

Clinical Functional and Outcome Measures for Schizophrenia Participants With and Without Diabetes at Enrollment

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To determine whether there was a difference in the course of schizophrenia between the 2 groups, the DM and non-DM participants were compared on each of the 36 outcome measures across the 3-year study period (Table 2). For descriptive purposes, scores for each outcome measure at enrollment and at the end of years 1, 2, and 3 are also presented. Only 2 of 36 outcome measures were significantly different between the 2 groups across the 3-year period, with the DM group reporting significantly more contacts with nonpsychiatrist physicians (p < .001) and poorer levels of physical health (p = .015). If correcting for multiple comparisons using the Bonferroni method, only the significant group difference on physical health becomes nonsignificant, as its p value is larger than the corrected threshold of .0014.

For 31 of the other outcome measures, the DM and non-DM groups did not significantly differ across the 3-year study period. The 2 groups did not significantly differ in level of core schizophrenia symptomatology, as assessed by the PANSS and its subscale scores, or in severity of depressive symptoms, as assessed by the MADRS. Both groups had MADRS scores consistent with a mild level of depressive symptoms.33 The groups did not significantly differ on psychiatric hospitalization and use of emergency services, nor did they differ on measures of legal and safety issues, substance use, productivity, activities and relationships, or quality-of-life measures.

For 3 outcome measures—violent behavior, suicide attempts, and illicit drug use—the incidences were too few to allow for statistical comparisons. Therefore, p values could not be calculated, and only summary statistics are shown.

The groups did not significantly differ on psychiatric medication treatment patterns across the 3-year study period. Antipsychotic medications were prescribed for 64 DM participants (94.1%) and 462 non-DM participants (96.1%) (p = .429). Among the DM group, 53 (77.9%) were treated with atypical antipsychotics and 39 (57.4%) with typical antipsychotics, compared with 389 (80.9%) and 248 (51.6%), respectively, for DM participants (p = .927 and p = .755, respectively). The 2 groups also did not differ on use of mood stabilizers (DM: N = 22 [32.4%]; non-DM: N = 220 [45.7%]; p = .174) or use of antidepressants (DM: N = 32 [47.1%]; non-DM: N = 241 [50.1%]; p = .345).

DISCUSSION

Contrary to study hypothesis, the 3-year course of clinical and functional outcomes in schizophrenia did not significantly differ between participants with and without preexisting diabetes. Of 36 outcome measures assessing various clinical and functional domains, the 2 groups significantly differed only on 2 physical health parameters: diabetic participants had more visits with nonpsychiatrist physicians, and they had poorer physical health. These differences are not surprising, as individuals with diabetes could be expected to utilize services for treatment of diabetes, and they had more comorbid medical conditions at study enrollment.

Across the 3-year study, the diabetes and nondiabetes groups did not significantly differ on the course of their psychotic and depressive symptomatology; the use of acute psychiatric care, such as psychiatric hospitalizations and emergency services; legal and safety issues; substance use; productivity; activities; relationships; or quality-of-life measures. These results suggest that the presence of a chronic physical condition did not adversely affect mental health.

Depressive symptoms are more common in people with diabetes than in the general population.17 Therefore, it is surprising that both groups experienced relatively mild levels of depressive symptoms and did not significantly differ in mean MADRS scores either at study enrollment or across the 3-year study period. In both groups, approximately half of the participants received antidepressant medication at some point during the study. Although the drivers of the current findings are unclear, it is possible that study participants had more stable diabetes. Another possibility is that the participants with diabetes had a less severe psychiatric illness profile at study enrollment, as reflected by slightly lower levels of positive symptoms, fewer psychiatric hospitalizations in the 6 months prior to enrollment, less substance use, and better general life satisfaction.

Interestingly, although fewer days of paid work at study enrollment were reported by those DM participants who had paid employment, there were no statistically significant differences between the 2 groups in the proportion of participants who worked for pay or who engaged in any productive activity.

Notably, participants with and without diabetes differed significantly at enrollment on the prevalence of other comorbid medical conditions, including hypertension, kidney dysfunction, and heart conditions other than heart attack. Most of the diabetic participants (79%) had at least 1 other medical condition, compared with 50% of the non-DM group. In light of the added medical burden associated with diabetes, one would expect participants with diabetes to have more frequent contact with nonpsychiatric physicians to address these medical needs. The current findings are consistent with previous research demonstrating the paucity in quality and quantity of medical care provided to people with chronic and severe mental illness.34,35

These data highlight the need to ensure that people with chronic mental illness receive comprehensive medical treatment for both their mental and physical needs. Optimal care may require mental health professionals to develop new approaches to manage physical symptoms in mentally ill individuals,5 including better collaboration with medical colleagues as well as increased attention to programs to prevent or reduce risk factors of common medical comorbidities.2 Druss and colleagues34 have shown that patient outcomes and medical care can be improved when medical care is provided on-site in the mental health clinic.

Among the strengths of this study are its naturalistic, long-term, prospective design; its repeated use of valid and reliable psychiatric measures; and its large and diverse sample, which is representative of patients treated in public health care systems across the United States. Study limitations include the fact that information on diabetes status and medical comorbidities was based on participant self-report rather than medical records or laboratory tests. No attempt was made to validate these participant reports, so we cannot rule out the possibility that the findings of no difference in psychiatric course between the 2 groups may have been due to invalid determination of diabetes status. In addition, approximately 5% of people with schizophrenia36 and 2% of the general population37 have undiagnosed diabetes, suggesting that some participants in the non-DM group may actually have had diabetes. Information on diabetes status was not collected after study enrollment; therefore, it is unknown who, if anyone, among the non-DM participants developed diabetes during this 3-year study. Furthermore, the current analyses did not assess whether diabetes was the direct cause of the differences between the 2 groups; they only addressed whether between-group differences existed. Lastly, these were secondary analyses and, as such, should be considered exploratory in nature pending replication of these findings in a separate sample.

The present findings, which suggest a similar course of schizophrenia in people with and without diabetes, do not lessen the importance of appropriate treatment for those with diabetes or the need for interventions to help prevent diabetes in people with schizophrenia. Studies have shown that individuals with serious mental illness can reduce symptoms of, and risk factors for, diabetes through diet, exercise, behavioral intervention, and pharmacotherapy.38–42

CONCLUSIONS

In this large prospective study of people with schizophrenia treated in usual care settings, the 3-year course clinical and functional outcomes did not significantly differ between participants with and without comorbid diabetes at study enrollment, although diabetic participants had poorer physical health and more contacts with nonpsychiatrist physicians. There is a need for a prospective incidence study to verify these findings. However, the results of this exploratory study highlight the preponderance of comorbid medical conditions in this vulnerable mentally ill population and the need for better collaboration between psychiatrists, primary care physicians, and specialty care physicians to help enhance quality of care for the mentally ill.

Acknowledgments

We wish to thank the site investigators and others who collaborated in the research. By site, they include Maryland: A. F. Lehman, M.D., M.S.P.H., University of Maryland School of Medicine and G. Gallucci, M.D., M.H.S., Johns Hopkins Bayview Medical Center; Colorado: C. Harding, Ph.D., University of Colorado (previously); Florida: D. Shern, Ph.D., and T. Saunders, M.S. (previously), Florida Mental Health Institute, University of South Florida; North Carolina: J. Swanson, Ph.D., L. A. Dunn, M.D., and M. Swartz, M.D., Duke University Medical School; California: R. L. Hough, Ph.D., and C. Barrio, Ph.D., Child and Adolescent Services Research Center and San Diego State University; and Connecticut: R. A. Rosenheck, M.D., and R. Desai, Ph.D., VA Connecticut Health Care System. Medstat Group: P. Russo, Ph.D., M.S.W., R.N. (previously), L. Palmer, Ph.D., L. Torres, M.B.A., and B. Cuffel, Ph.D. (previously). Eli Lilly and Co.: D. Buesching, Ph.D., B. M. Johnstone, Ph.D., and T. Croghan, M.D. (previously). Consultants: D. Salkever, Ph.D., and E. Slade, Ph.D. (previously), Johns Hopkins University and W. Hargreaves, Ph.D., and M. Shumway, Ph.D., University of California, San Francisco.

Footnotes

The United States Schizophrenia Care and Assessment Program study was supported by Eli Lilly and Co., and administered by the Medstat Group. This study is registered at lillytrials.com under identifier 4278.

Some of the data contained in this article were previously presented at the Institute on Psychiatric Services in Boston, Mass., Oct. 29–Nov. 2, 2003.

The authors would like to thank Rongmei Zhang, M.S. (formerly an employee of Eli Lilly and Co.), for her expert help with statistical analyses. Additional acknowledgments appear at the end of this article.

Drs. Ascher-Svanum, Zhu, Faries, and Jacobson are employees of Eli Lilly and Co. Dr. Ernst is a former employee of Eli Lilly and Co., and is presently an employee of Premier, Inc. Dr. Doebbeling has served as a consultant to Eli Lilly and Co., and has received grant/research support from National Institute of Mental Health, National Alliance for Research on Schizophrenia and Depression, U.S. Department of Defense, and Mental Health America of Indiana.

REFERENCES CITED

  1. Daumit GL, Pratt LA, and Crum RM. et al. Characteristics of primary care visits for individuals with severe mental illness in a national sample. Gen Hosp Psychiatry. 2002 24:391–395. [DOI] [PubMed] [Google Scholar]
  2. Sokal J, Messias E, and Dickerson FB. et al. Comorbidity of medical illnesses among adults with serious mental illness who are receiving community psychiatric services. J Nerv Ment Dis. 2004 192:421–427. [DOI] [PubMed] [Google Scholar]
  3. Mukherjee S, Decina P, and Bocola V. et al. Diabetes mellitus in schizophrenic patients. Compr Psychiatry. 1996 37:68–73. [DOI] [PubMed] [Google Scholar]
  4. Ryan M, Collins P, Thakore JH.. Impaired fasting glucose tolerance in first-episode, drug-naive patients with schizophrenia. Am J Psychiatry. 2003;160:284–289. doi: 10.1176/appi.ajp.160.2.284. [DOI] [PubMed] [Google Scholar]
  5. Chafetz L, White MC, and Collins-Bride G. et al. The poor general health of the severely mentally ill: impact of schizophrenic diagnosis. Community Ment Health J. 2005 41:169–184. [DOI] [PubMed] [Google Scholar]
  6. Curkendall SM, Mo J, and Glasser DB. et al. Cardiovascular disease in patients with schizophrenia in Saskatchewan, Canada. J Clin Psychiatry. 2004 65:715–720. [DOI] [PubMed] [Google Scholar]
  7. Brown S, Inskip H, Barraclough B.. Causes of the excess mortality of schizophrenia. Br J Psychiatry. 2000;177:212–217. doi: 10.1192/bjp.177.3.212. [DOI] [PubMed] [Google Scholar]
  8. Cournos F, McKinnon K, and Sullivan G. Schizophrenia and comorbid human immunodeficiency virus or hepatitis C virus. J Clin Psychiatry. 2005 66suppl 6. 27–33. [PubMed] [Google Scholar]
  9. Buse JB, Cavazzoni P, and Hornbuckle K. et al. A retrospective cohort study of diabetes mellitus and antipsychotic treatment in the United States. J Clin Epidemiol. 2003 56:164–170. [DOI] [PubMed] [Google Scholar]
  10. Cohen D, Dekker JJ, and Peen J. et al. Prevalence of diabetes mellitus in chronic schizophrenic inpatients in relation to long-term antipsychotic treatment. Eur Neuropsychopharmacol. 2006 16:187–194. [DOI] [PubMed] [Google Scholar]
  11. Ollendorf DA, Joyce AT, Rucker M.. Rate of new-onset diabetes among patients treated with atypical or conventional antipsychotic medications for schizophrenia. MedGenMed. 2004;6:5. [PMC free article] [PubMed] [Google Scholar]
  12. Koran LM, Sheline Y, and Imai K. et al. Medical disorders among patients admitted to a public-sector psychiatric inpatient unit. Psychiatr Serv. 2002 53:1623–1625. [DOI] [PubMed] [Google Scholar]
  13. Chwastiak L, Rosenheck R, Leslie D.. Impact of medical comorbidity on the quality of schizophrenia pharmacotherapy in a national VA sample. Med Care. 2006;44:55–61. doi: 10.1097/01.mlr.0000188993.25131.48. [DOI] [PubMed] [Google Scholar]
  14. Dixon LB, Kreyenbuhl JA, and Dickerson FB. et al. A comparison of type 2 diabetes outcomes among persons with and without severe mental illnesses. Psychiatr Serv. 2004 55:892–900. [DOI] [PubMed] [Google Scholar]
  15. Ascher-Svanum H, Faries DE, and Zhu B. et al. Medication adherence and long-term functional outcomes in the treatment of schizophrenia in usual care. J Clin Psychiatry. 2006 67:453–460. [DOI] [PubMed] [Google Scholar]
  16. Faries D, Ascher-Svanum H, and Zhu B. et al. Antipsychotic monotherapy and polypharmacy in the naturalistic treatment of schizophrenia with atypical antipsychotics. BMC Psychiatry. 2005 5:26. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Anderson RJ, Freedland KE, and Clouse RE. et al. The prevalence of comorbid depression in adults with diabetes: a meta-analysis. Diabetes Care. 2001 24:1069–1078. [DOI] [PubMed] [Google Scholar]
  18. Smith DW.. The population perspective on quality of life among Americans with diabetes. Qual Life Res. 2004;13:1391–1400. doi: 10.1023/B:QURE.0000040785.59444.7c. [DOI] [PubMed] [Google Scholar]
  19. Ascher-Svanum H, Zhu B, and Faries D. et al. Time to discontinuation of atypical versus typical antipsychotics in the naturalistic treatment of schizophrenia. BMC Psychiatry. 2006 6:8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Van Dorn RA, Swanson JW, and Swartz MS. et al. The effects of race and criminal justice involvement on access to atypical antipsychotic medications among persons with schizophrenia. Ment Health Serv Res. 2005 7:123–134. [DOI] [PubMed] [Google Scholar]
  21. Swanson JW, Swartz MS, and Elbogen EB. et al. Reducing violence risk in persons with schizophrenia: olanzapine versus risperidone. J Clin Psychiatry. 2004 65:1666–1673. [DOI] [PubMed] [Google Scholar]
  22. Slade EP, Salkever DS, and Rosenheck R. et al. Cost-sharing requirements and access to mental health care among Medicare enrollees with schizophrenia. Psychiatr Serv. 2005 56:960–966. [DOI] [PubMed] [Google Scholar]
  23. Skinner KM, Miller DR, and Lincoln E. et al. Concordance between respondent self-reports and medical records for chronic conditions: experience from the Veterans Health Study. J Ambulatory Care Manage. 2005 28:102–110. [DOI] [PubMed] [Google Scholar]
  24. Kay SR, Fiszbein A, Opler LA.. The Positive and Negative Syndrome Scale (PANSS) for schizophrenia. Schizophr Bull. 1987;13:261–276. doi: 10.1093/schbul/13.2.261. [DOI] [PubMed] [Google Scholar]
  25. Montgomery SA, Asberg M.. A new depression scale designed to be sensitive to change. Br J Psychiatry. 1979;134:382–389. doi: 10.1192/bjp.134.4.382. [DOI] [PubMed] [Google Scholar]
  26. Heinrichs DW, Hanlon TE, Carpenter WT Jr. The Quality of Life Scale: an instrument for rating the schizophrenic deficit syndrome. Schizophr Bull. 1984;10:388–398. doi: 10.1093/schbul/10.3.388. [DOI] [PubMed] [Google Scholar]
  27. Endicott J, Spitzer RL, and Fleiss JL. et al. The Global Assessment Scale: a procedure for measuring overall severity of psychiatric disturbance. Arch Gen Psychiatry. 1976 33:766–771. [DOI] [PubMed] [Google Scholar]
  28. Lehman AF, Fischer EP, and Postrado L. et al. The Schizophrenia Care and Assessment Program Health Questionnaire (SCAP-HQ): an instrument to assess outcomes of schizophrenia care. Schizophr Bull. 2003 29:247–256. [DOI] [PubMed] [Google Scholar]
  29. Lehman A.. A quality of life interview for the chronically mentally ill. Eval Progra Plann. 1988;11:51–62. [Google Scholar]
  30. Ware J Jr, Kosinski M, Keller SD.. A 12-Item Short-Form Health Survey: construction of scales and preliminary tests of reliability and validity. Med Care. 1996;34:220–233. doi: 10.1097/00005650-199603000-00003. [DOI] [PubMed] [Google Scholar]
  31. Mallinckrodt CH, Sanger TM, and Dube S. et al. Assessing and interpreting treatment effects in longitudinal clinical trials with missing data. Biol Psychiatry. 2003 53:754–760. [DOI] [PubMed] [Google Scholar]
  32. Liang K, Zeger S.. Longitudinal data analysis using generalized linear models. Biometrika. 1986;73:13–22. [Google Scholar]
  33. Snaith RP, Harrop FM, and Newby DA. et al. Grade scores of the Montgomery-Asberg Depression and the Clinical Anxiety Scales. Br J Psychiatry. 1986 148:599–601. [DOI] [PubMed] [Google Scholar]
  34. Druss BG, Rohrbaugh RM, and Levinson CM. et al. Integrated medical care for patients with serious psychiatric illness: a randomized trial. Arch Gen Psychiatry. 2001 58:861–868. [DOI] [PubMed] [Google Scholar]
  35. Druss BG, Rosenheck RA, and Desai MM. et al. Quality of preventive medical care for patients with mental disorders. Med Care. 2002 40:129–136. [DOI] [PubMed] [Google Scholar]
  36. Taylor D, Young C, and Mohamed R. et al. Undiagnosed impaired fasting glucose and diabetes mellitus amongst inpatients receiving antipsychotic drugs. J Psychopharmacol. 2005 19:182–186. [DOI] [PubMed] [Google Scholar]
  37. Gregg EW, Cadwell BL, and Cheng YJ. et al. Trends in the prevalence and ratio of diagnosed to undiagnosed diabetes according to obesity levels in the US. Diabetes Care. 2004 27:2806–2812. [DOI] [PubMed] [Google Scholar]
  38. Brar J, Ganguli R, and Pandina G. et al. Effects of behavioral therapy on weight loss in overweight and obese patients with schizophrenia or schizoaffective disorder. J Clin Psychiatry. 2005 66:205–212. [DOI] [PubMed] [Google Scholar]
  39. Henderson DC, Copeland PM, and Daley TB. et al. A double-blind, placebo-controlled trial of sibutramine for olanzapine-associated weight gain. Am J Psychiatry. 2005 162:954–962. [DOI] [PubMed] [Google Scholar]
  40. Hoffmann VP, Ahl J, and Meyers A. et al. Wellness intervention for patients with serious and persistent mental illness. J Clin Psychiatry. 2005 66:1576–1579. [DOI] [PubMed] [Google Scholar]
  41. Krosnick A, Wilson MG.. A retrospective chart review of the clinical effects of atypical antipsychotic drugs on glycemic control in institutionalized patients with schizophrenia and comorbid diabetes mellitus. Clin Ther. 2005;27:320–326. doi: 10.1016/j.clinthera.2005.02.017. [DOI] [PubMed] [Google Scholar]
  42. Vreeland B, Minsky S, and Menza M. et al. A program for managing weight gain associated with atypical antipsychotics. Psychiatr Serv. 2003 54:1155–1157. [DOI] [PubMed] [Google Scholar]

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