Investigators made use of the Swedish National Diabetes Register to investigate trends in all-cause mortality and cardiovascular disease in 36,869 people with type 1 diabetes and 457,473 with type 2 diabetes.
The baseline mean glycated hemoglobin level was 8.2% in people with type 1 diabetes and 7.1% in those with type 2 diabetes. Mean duration of diabetes before entry into the registry was 20 years in the diabetes type 1 group and 6 years in the type 2 group. During follow-up (median, 15 years), both diabetes groups had decreases in mean LDL cholesterol and blood pressure.
The researchers examined mortality in the diabetes groups and in separate general-population groups matched by age, sex, and county. All-cause mortality declined by 31 deaths per 10,000 person-years for those with type 1 diabetes and 14 per 10,000 for controls, a nonsignificant difference. The decline in cardiovascular mortality was also nonsignificantly different (rate in diabetes type 1 group, −26/10,000 person-years).
For those with type 2 diabetes, all-cause mortality changed by −70 deaths per 10,000, compared with −135 per 10,000 in controls, a 13% greater change in controls (P<0.001). The control group showed a 6% significantly greater reduction in cardiovascular deaths.
Hospitalizations for cardiovascular disease declined in both diabetes groups to a greater extent than in the control groups.
As reflected in this study (and as is generally known), we have just lived through a remarkable reduction in cardiovascular mortality (along with a growth in prescriptions for statins and antihypertensive medications). People with diabetes have also experienced this decline, although somewhat less so for those with type 2 diabetes. However, this article does not clarify whether the slower decline in mortality results from the illness or from patients' behaviors and comorbid conditions.
di Harlan M. Krumholz, MD, SM Reviewing Ingelfinger JR and Jarcho JA., N Engl J Med 2017 Apr 13; 376:1473