The association between passive smoking and type 2 diabetes: a meta-analysis.

The number of people with diabetes has been exponentially increasing. A number of reports in the literature have suggested that exposure to passive smoke may play a key role in the development of diabetes; however, the association has not been jointly summarized yet. In this meta-analysis, 2 databases were searched to identify studies, and the references of these studies were scanned for further studies. Fourteen studies on the relationship between passive smoking and diabetes were included. After all the studies were pooled, the results showed that passive smoking was significantly associated with an increased risk of type 2 diabetes in a random model. The subgroup analysis results were consistent with overall results regardless of type of study design, age, gender, adjustment of dependent variables, area, or study quality. Sensitivity analysis indicated that the overall results were reliable. There was no publication bias observed in the selected studies.