Association between secondhand smoke and glycemic control in adult diabetes patients

Diabetes is a major chronic disease, and many studies have shown an association between diabetes with severe complications and certain causes of diabetes, including secondhand smoke. Smoking has been considered a significant issue around the world, and research has been conducted on its relationship with diseases including diabetes. However, previous studies have focused on the onset of diabetes, rather than glycemic control in patients with diabetes. Thus, this study aims to provide evidence of a relationship between secondhand smoke and glycemic control. We conducted a cross-sectional study using data from the Korea National Health and Nutrition Examination Survey (2007-2014). We included 1168 male and 1248 female survey participants. Exposure to secondhand smoke at home and/or at workplaces was considered the primary independent variable, and glycemic control was represented by HbA1c levels. Chi-squared tests and logistic regression analysis were performed to evaluate the association. A significant association was found between secondhand smoke and glycemic control (male at home, odds ratio [OR]: 0.36, 95% confidence interval [CI]: 0.14-0.90; female at both locations, OR: 0.29, 95% CI: 0.11-0.74). The sub-group analysis showed a negative association of diabetes management with secondhand smoke in both sexes, regardless of income status or healthy/unhealthy behaviors. Exposure to secondhand smoke at home was revealed as a risk factor for poor glycemic control. Thus, healthcare providers should help diabetes patients to avoid secondhand smoke by educating them on the dangers of secondhand smoke.