Somatic neuropathy is an independent predictor of all- and diabetes-related mortality in type 2 diabetic patients: A population-based 5-year follow-up study (KCIS No. 29)

Background and purpose: To investigate the relationships of diabetic neuropathy to all-cause and diabetes-related mortality in patients with type 2 diabetes after controlling for significant correlates. Methods: We examined 326 patients diagnosed as diabetic polyneuropathy by nerve conduction study in Keelung city, Taiwan, in 2002 and followed them up to ascertain the cause and date of death until the end of 2006. The cause and date of death were recorded for the deceased patients. Information on significant correlates in association with diabetic polyneuropathy and all-cause and diabetes-related mortality was also collected. Results: With median follow-up time of 62.28months, 44 patients with type 2 diabetes died. The cause of death related to diabetes accounted for 59% (n=26) of the deceased. Univariate analysis shows that the presence of diabetic neuropathy confers higher risk for all-cause mortality (hazard ratio [HR]=4.88) and mortality from diabetes (HR=6.58). The significant finding still persisted after adjustment for age, gender, blood pressure, smoking, history of cardiovascular/cerebrovascular disease, duration of diabetes, waist circumference, fasting plasma glucose, total cholesterol, hemoglobin, and creatinine (adjusted HR=4.44 for all-cause death and adjusted HR=11.82 for diabetes-related mortality, respectively). Conclusions: Diabetic polyneuropathy was an independent predictor for all-cause and diabetes-related mortality. The presence of neuropathy together with other significant prognostic factors is informative to predict all-cause death and death from diabetes-related disease for patients diagnosed as type 2 diabetes.