Survival in Patients With Type 2 Diabetes in a Swedish Community

Abstract

OBJECTIVE—To explore risk factors for all-cause mortality in patients with type 2 diabetes treated in primary care. RESEARCH DESIGN AND METHODS—A prospective population-based study of 400 patients with type 2 diabetes who consecutively completed an annual checkup in primary care in Skara, Sweden, during 1992–1993. Vital status was ascertained to year 2000. Baseline characteristics as predictors for mortality were analyzed by Cox regression and expressed as relative risks (RRs), with 95% CIs. RESULTS—During a mean follow-up time of 5.9 years, 131 patients died (56 deaths per 1,000 patients per year). In both sexes, all-cause mortality was predicted by HbA1c (by 1%; RR 1.14, 95% CI 1.01–1.27), and by LDL-to-HDL cholesterol ratios (1.15, 1.00–1.32). Increased mortality was also seen with prevalent hypertension (1.72, 1.21–2.44), microalbuminuria (1.87, 1.27–2.76), and previous cardiovascular disease (1.70, 1.15–2.50). Subanalyses revealed that increased mortality related to HbA1c was restricted to hypertensive patients with type 2 diabetes (1.23, 1.04–1.47). Serum triglycerides (by 1 mmol/l) predicted all-cause mortality in women (1.25, 1.06–1.47). CONCLUSIONS—Poor glucose and lipid control and hypertension predicted all-cause mortality. Survival was also predicted by prevalent microalbuminuria and by previous cardiovascular disease. Confirming results from clinical trials, this population-based study has implications for primary and secondary prevention.