Diabetes and Mortality From Respiratory Diseases: The Japan Collaborative Cohort Study

BACKGROUND: Little evidence is available about the association between diabetes and respiratory disease mortality among Japanese populations. We aimed to explore the association between diabetes and the risk of respiratory diseases mortality through a nationwide prospective study in Japan. METHODS: We followed 95,056 participants (39,925 men and 55,131 women) for a median 17.1 years. The information about diabetes status, sociodemographic characteristics, and lifestyles was collected at baseline. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) of mortality from respiratory diseases associated with baseline diabetes status. RESULTS: We identified 2,838 deaths from total respiratory diseases (1,759 respiratory infection, 432 chronic obstructive pulmonary disease, and 647 other respiratory diseases). The association between diabetes and total respiratory disease mortality was statistically significant among women (HR 1.81; 95% CI, 1.39–2.37) but of borderline statistical significance in men (P for interaction <0.01). Besides, there were significant associations between diabetes and mortality from respiratory infection among both men and women (HR 1.39; 95% CI, 1.10–1.76 and HR 2.30; 95% CI, 1.71–3.11, respectively; P for interaction <0.001). However, we failed to detect any statistically significant association between diabetes and COPD mortality. Moreover, the subgroup analysis revealed that the association between diabetes and total respiratory disease mortality was stronger in never smokers when compared with ever smokers (P for interaction = 0.02). CONCLUSIONS: Significant association was observed between diabetes and the risk of total respiratory disease mortality, in particular from respiratory infection. Prevention and control of respiratory diseases, especially respiratory infection, should be paid more attention among people with diabetes in clinical and public health practice.