The presence of the metabolic syndrome (MetS) is an important risk factor for cardiovascular disease and diabetes. There are limited data on the prevalence of MetS in patients with schizophrenia at the onset of the disorder and specifically no data on patients treated in the era when only first-generation antipsychotics were available.
Methods: Data from a historic cohort of consecutively admitted first-episode patients with schizophrenia treated with first-generation antipsychotics (FGAs) were compared with an age and sex matched series of consecutive first-episode patients treated only with second-generation antipsychotics (SGAs). Rates of MetS were compared at baseline and after on average 3 years of treatment exposure.
Results: At first episode there was no difference in the prevalence of MetS between the historic and the current cohort. Rates of MetS increased over time in both groups, but patients started on SGAs had a three times higher incidence rate of MetS (Odds Ratio 3.6, CI 1.7-7.5). The average increase in weight and body mass index was twice as high in patients started on SGA. The difference between the FGA and SGA group was no longer significant when patients started on clozapine and olanzapine were excluded.
Conclusion: Rates of MetS at the first episode of schizophrenia today are not different from those of patients 15 to 20 years ago. This finding counters the notion that the high rates of metabolic abnormalities in patients with schizophrenia currently reported are mainly due to lifestyle changes over time in the general population. Some SGAs have a significantly more negative impact on the incidence of MetS compared to FGAs in first-episode patients.