Causes of Deaths and Estimated Life Expectancy among People with Diabetes: A Retrospective Cohort Study in a Diabetes Clinic

We sought to estimate the exact causes of death, mortality rate and life expectancy of diabetes patients by analyzing death records in a diabetes specialist clinic in Japan. Of the 6,140 participants included in our analysis, the average age was 58.1 years and 77% were men. A total of 261 deaths were recorded during the total follow-up period of 24,079 total person-years. The leading causes of death were cancer, heart diseases and cerebrovascular diseases. Using a life table prepared from the mortality rates estimated with the exponential distribution model, a life expectancy at 40 years was 39.2 years (95% confidence interval 37.9-40.2 years) for men and 43.6 years (95% confidence interval 41.8-45.3 years) for women. Although the present results must be interpreted with caution, compared with populations with diabetes surveyed during similar periods by the Japan Diabetes Society, our diabetes patients had similar ranking of the causes of death.