Background and aims: An excess of long-term mortality in type 2 diabetes is mainly due to cardiac diseases, predicted by diabetes-related conditions; less is known about early death from clinical diagnosis. The aim of this study was to evaluate pattern and predictors of mortality after a 4.5 year follow-up in a cohort of type 2 diabetic patients, according to diabetes duration.
Methods and results: A mortality follow-up was carried out in 1200 patients with < or = 5 years diabetes duration and 2692 patients with >5 (median 2 and 15) years diabetes duration in 1995. Four-year survival was 92.0% and 83.7%, respectively; most deaths are due to cardiovascular diseases (36% and 41%, respectively). The duration of diabetes is no longer a significant predictor of death after adjustments for age, HbA1c and chronic complications (which are all significantly higher in patients who have had diabetes for longer time). In a Cox proportional hazard model, best predictors of death are nephropathy, insulin therapy and pre-existent co-morbidity in both groups. Nephropathy is significantly associated with cardiovascular deaths in the younger cohort.
Conclusion: Clinical nephropathy is a significant predictor of early and late mortality from clinical diagnosis, above all cardiovascular deaths, indicating that an aggressive approach should be adopted for prevention or treatment of renal impairment right from the clinical onset of diabetes.