Mortality of patients with type 2 diabetes in Taiwan: a 10-year nationwide follow-up study

Abstract

Aims: This study aims to investigate the distribution of underlying-causes-of-death (UCOD) among deceased patients with type 2 diabetes mellitus (DM) in Taiwan and assess the influence of socio-demographic characteristics on mortality in type 2 DM patients.

Methods: A cohort study on patients who sought medical care for type 2 DM from 2000 to 2008 was conducted on 65,599 type 2 DM patients retrieved from the 1-million beneficiaries randomly selected from Taiwan's National Health Insurance Database. The study cohort was then linked to Taiwan's Mortality Registry to ascertain the patients who died between 2000 and 2009. We examined the distribution of UCOD in the deceased subjects. The hazard ratios of mortality in relation to socio-demographic characteristics were estimated from Cox proportional hazard model.

Results: The leading causes of death in type 2 DM included neoplasm (22.68%), cardiovascular diseases (21.46%), and endocrine diseases (20.78%). Male gender and older ages were associated with significantly increased risk of mortality. In addition, lower urbanization and greater co-morbidity score were also significantly associated with an increased risk of mortality with a dose-gradient pattern.

Conclusions: Neoplasm accounts for the largest portion (22.68%) of deaths in type 2 DM patients closely followed by with cardiovascular diseases (21.46%). An increased risk of mortality in type 2 DM patients in lower urbanized areas may reflect poor diabetes care in these areas.

Keywords: Cohort studies; Geographic variation; Mortality rate; Type 2 diabetes mellitus; Urbanization.