The impact of obesity on health care costs among persons with schizophrenia.
BACKGROUND
Obesity is the second leading cause of preventable death in the United States and is twice as common among individuals with schizophrenia as the general population.


METHODS
Data from the Clinical Antipsychotic Trials of Intervention Effectiveness, a multisite trial of antipsychotic pharmacotherapy in 1460 patients with schizophrenia, were used to examine the relationships between body mass index (BMI) and medical costs.


RESULTS
ANCOVA analyses found significant increases in both psychiatric and nonpsychiatric medication costs associated with increasing BMI and a significant, but smaller, difference in costs of outpatient medical-surgical service utilization: US$41 per month for morbidly obese patients compared to US$26 per month for patients of normal weight (F=2.4, P=.04). In multivariable logistic regression analyses, morbid obesity was associated with significantly increased odds of any outpatient medical-surgical service costs. When compared to observations of BMI>35, BMI observations within the normal range (18.5-24.9) were half as likely to be associated with any outpatient medical-surgical costs (OR=0.53; 95% CI=0.45, 0.63).


CONCLUSIONS
In this large sample of persons with schizophrenia, obesity was associated with increased outpatient general medical service and medication costs even after controlling for demographic characteristics and medical comorbidity, but the absolute dollar amount was small.
Chwastiak
Lydia A
LA
Department of Psychiatry, Yale School of Medicine, New Haven, CT 06519, USA. lydia.chwastiak@yale.edu
Rosenheck
Robert A
RA
McEvoy
Joseph P
JP
Stroup
T Scott
TS
Swartz
Marvin S
MS
Davis
Sonia M
SM
Lieberman
Jeffrey A
JA
D000293:Adolescent; D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D017048:Health Care Costs / Q000706:statistics & numerical data*; D005102:Health Expenditures / Q000639:trends*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000191:economics*; D016032:Randomized Controlled Trials as Topic; D012559:Schizophrenia / Q000150:complications / Q000188:drug therapy; D014481:United States; D055815:Young Adult