Clozapine and Hypertension: A Chart Review of 82 Patients

Objective: Clozapine has been linked to significant weight gain and increase in serum lipids and appears to negatively impact glucose metabolism. In this retrospective chart review study, we examine changes in systolic and diastolic blood pressure and treatment for hypertension in clozapine-treated patients.

Method: Data on demographics and systolic and diastolic blood pressure were examined for up to 5 years (September 1987 to September 1992) in 82 patients treated with clozapine. Rates of hypertension treatment in clozapine-treated patients were compared with patients receiving conventional antipsychotics (N = 56) and other atypical antipsychotic agents (N = 102).

Results: The mean age of the 82 patients at the time of clozapine initiation was 36.4 ± 7.8 years, with 22 (27%) female, 75 (91%) white, 3 (4%) black, 3 (4%) Hispanic, and 1 (1%) Asian. The baseline weight was 175.5 ± 34.0 lb (79.0 ± 15.3 kg) and baseline body mass index was 26.9 ± 5.0 kg/m². There was a significant increase in systolic blood pressure (p = .0004) and diastolic blood pressure (p = .0001). Overall, 22 patients (27%) received treatment for hypertension following clozapine initiation. Only 2 (4%) of 56 patients in the conventional antipsychotic group and 9 (9%) of 102 patients in the other atypical antipsychotic group (olanzapine, N = 6; risperidone, N = 3) received treatment for hypertension.

Conclusion: Our findings suggest that long-term clozapine treatment is associated with increased rates of hypertension, which may have a significant impact on medical morbidity and mortality.