This study assessed the association between second-generation antipsychotic medications and risk of pneumonia requiring hospitalization in patients with schizophrenia because the evidence is limited in the population. We enrolled a nationwide cohort of 33,024 inpatients with schizophrenia ranged in age from 18 to 65 years, who were derived from the National Health Insurance Research Database in Taiwan from 2000 to 2008. Cases (n = 1741) were defined as patients who developed pneumonia after their first psychiatric admissions. Risk set sampling was used to match each case with 4 controls by age, sex, and the year of the first admission based on nested case-control study. Antipsychotic exposure was categorized by type, duration, and daily dose, and the association between exposure and pneumonia was assessed using conditional logistic regression. We found that current use of clozapine (adjusted risk ratio = 3.18, 95% CI: 2.62-3.86, P < .001) was associated with a dose-dependent increase in the risk. Although quetiapine, olanzapine, zotepine, and risperidone were associated with increased risk, there was no clear dose-dependent relationship. Amisulpride was associated with a low risk of pneumonia. The use of clozapine combined with another drug (olanzapine, quetiapine, zotepine, risperidone, or amisulpride), as assessed separately, was associated with increased risk for pneumonia. In addition, with the exception of amisulpride, each drug was associated with increased risk for pneumonia at the beginning of treatment. Clinicians who prescribe clozapine to patients with schizophrenia should closely monitor them for pneumonia, particularly at the start of therapy and when clozapine is combined with other antipsychotics.

The burden of diabetes is increasing globally. Identifying novel preventable risk factors is an urgent need. In 2011, the U.S. National Toxicological Program (NTP) conducted a workshop to evaluate the epidemiologic and experimental evidence on the relationship of environmental chemicals with obesity, diabetes and metabolic syndrome. Although the evidence was insufficient to establish causality, the NTP workshop review identified an overall positive association between some environmental chemicals and diabetes. In this systematic review, our objective was to summarize the epidemiological research published since the NTP workshop. We identified a total of 29 articles (7 on arsenic, 3 on cadmium, 2 on mercury, 11 on persistent organic pollutants, 3 on phthalates and 4 on bisphenol A) including 7 prospective studies. Considering consistency, temporality, strength, dose-response, and biological plausibility (confounding), we concluded that the evidence is suggestive but not sufficient for a relationship between arsenic and persistent organic pollutants, and insufficient for mercury, phthalates and bisphenol A. For cadmium the epidemiologic evidence does not seem to suggest an association with diabetes. Important research questions include the need of additional prospective studies and the evaluation of the dose-response relationship, the role of joint exposures, and effect modification with other comorbidities and genetic variants.