Patients with type 2 diabetes who had five risk factors within target ranges appeared to have at most a marginal excess risk of death, myocardial infarction, or stroke compared with the general population, a study found.
To investigate whether the excess risk of death and cardiovascular events among patients with type 2 diabetes could be reduced or eliminated, researchers conducted a cohort study among 271,174 patients with type 2 diabetes who were registered in the Swedish National Diabetes Register and matched them with 1,355,870 controls on the basis of age, sex, and county.
Patients with diabetes were assessed according to five risk factors: elevated HbA1c level (≥7%), elevated LDL cholesterol level (≥2.5 mmol/L or 97 mg/dL), albuminuria, smoking, and elevated blood pressure (systolic ≥140 mm Hg or diastolic ≥80 mm Hg). The relationship between risk factors and cardiovascular outcomes was also assessed. Results were published Aug. 16 by the New England Journal of Medicine.
Among patients with type 2 diabetes, risk of outcomes decreased stepwise for each risk factor within the target range, the study found. Among patients with diabetes and all five risk factors within target ranges, hazard ratios were 1.06 (95% CI, 1.00 to 1.12) for death from any cause, 0.84 (95% CI, 0.75 to 0.93) for myocardial infarction, and 0.95 (95% CI, 0.84 to 1.07) for stroke versus controls.
Patients with type 2 diabetes who were younger than age 55 years and in whom all five risk factors were outside the target ranges had the highest excess risk of hospitalization for heart failure of all the outcomes assessed versus controls (hazard ratio, 11.35; 95% CI, 7.16 to 18.01). The overall hazard ratio for hospitalization for heart failure among patients with no risk factors outside the target ranges compared to controls was 1.45 (95% CI, 1.34 to 1.57). Smoking was the strongest predictor of death, the authors noted.
“The study indicates that having all five risk-factor variables within the target ranges could theoretically eliminate the excess risk of acute myocardial infarction,” the authors wrote. “However, there was a substantial excess risk of hospitalization for heart failure among patients who had all the variables within target ranges.”