O R I G I N A L R E S E A R C H Relationship between obesity and antipsychotic drug use in the adult population: A longitudinal, retrospective claim database study in Primary Care settings Antoni Sicras-Mainar1 Ruth Navarro-Artieda2 Javier Rejas-Gutiérrez3 Milagrosa Blanca-Tamayo4 1Planning Management, Badalona Serveis Assistencials S.A., Badalona, Barcelona, Spain; 2Medical Documentation Service, Hospital Germans Trías i Pujol, Badalona, Barcelona, Spain; 3Health Outcomes Research Derpartment, Medical Unit, Pfizer Spain, Alcobendas, Madrid, Spain; 4Department of Psychiatry, Badalona Serveis Assistencials S.A., Badalona, Barcelona, Spain Correspondence:Antoni Sicras-Mainar Badalona Serveis Assistencials, S.A., Planning Management, Calle Gaietà Soler 6-8, PO Box 08911, Badalona, Barcelona, Spain Tel +34 93 507 26 84 Fax +34 93 389 32 86 Email asicras@bsa.gs Objective: To describe the association between obesity and the use of antipsychotic drugs (APDs) in adult outpatients followed-up on in ﬁve Primary Care settings. Methods: A longitudinal, retrospective design study carried out between July 2004 and June 2005, in patients who were included in a claim database and for whom an APD treatment had been registered. A body mass index (BMI) 30 kg/m2 was deﬁned as obesity. The main measurements were: use of APDs, demographics, medical background and co-morbidities, and clinical parameters. Logistic regression analysis and ANCOVA with Bonferroni adjustment were applied to correct the model. Results: A total of 42,437 subjects (mean age: 50.8 (18.4) years; women: 54.5%; obesity: 27.3% [95% conﬁdence intervals (CI), 26.9%–27.7%]) were analyzed. A total of 1.3% of the patients were receiving APDs, without statistical differences in distribution by type of drug (typical: 48.8%; atypical: 51.2%). Obesity was associated with the use of APDs [OR = 1.5 (CI: 1.3–1.8)], hypertension [OR = 2.4 (CI: 2.2–2.5)], diabetes [OR = 1.4 (CI: 1.3–1.5)] and dyslipidemia [OR = 1.3 (CI: 1.2–1.4)], p 0.0001 in all cases. BMI was signiﬁcantly higher in subjects on APDs; 28.8 vs. 27.3 kg/m2, p = 0.002, and remained higher after adjusting by age and sex (mean difference 0.4 (CI: 0.1–0.7), p 0.01). After adjusting by age, sex and the Charlson index, obese subjects generated higher average annual total costs than nonobese subjects; 811 (CI: 787–835) vs. 694 (CI: 679–709), respectively, p 0.001. Conclusions: Obesity was associated with the use of APDs, regardless of the type of drug, and with the presence of hypertension, diabetes and dyslipidemia. Obesity was also associated with substantially higher health care costs. Keywords: Obesity, claim database, retrospective study, antipsychotic use, Primary Care set- ting, resources utilization, health care costs Introduction Metabolic disorders such as obesity, diabetes or dyslipidemia increase the risk of cardiovascular events (Guallar-Castillón et al 2002). Speciﬁcally, obesity exerts an unquestionable impact on population health, due to its high associated morbidity- mortality (Guallar-Castillón et al 2002; Mackin et al 2005). Its prevalence in the general population ranges between 6% and 20% (The Netherlands, USA), with an increased presence in females and a trend to increase with age, reaching a peak in the decade of 40–50 years. In Spain, the data provided by the Spanish Society for Study of Obesity (SEEDO) (Aranceta-Bartrina et al 2005), and also reported by different studies, indicate percentages in excess of 14%, with a clear tendency to gradually increase in the future (Aranceta-Bartrina et al 2005; Gutiérrez-Fisac et al 2005). Neuropsychiatric Disease and Treatment 2008:4(1) 219–226 © 2008 Sicras-Mainar et al, publisher and licensee Dove Medical Press Ltd.This is an Open Access article which permits unrestricted noncommercial use, provided the original work is properly cited. 219