A 12-year follow-up study of all-cause and cardiovascular mortality among 10,532 people newly diagnosed with Type 2 diabetes in Tayside, Scotland

Diabet Med. 2010 Oct;27(10):1124-9. doi: 10.1111/j.1464-5491.2010.03075.x.

Abstract

Aims: To determine absolute and relative risks of all-cause and cardiovascular mortality among patients newly diagnosed with Type 2 diabetes.

Methods: In an observational cohort study using record-linkage databases, based in Tayside, Scotland, UK, we identified newly diagnosed patients with Type 2 diabetes in 1993-2004. We also identified a set of non-diabetic comparators from lists of patients registered with a general practice, individually matched to the diabetic patients by sex, age and deprivation. We followed up patients for mortality and cardiovascular mortality over a 12-year period and calculated hazard ratios using Cox regression.

Results: There were 10,532 patients with Type 2 diabetes and 21,056 non-diabetic comparators. Diabetic patients in every age/sex group had higher absolute mortality rates. Even taking deprivation into account, the hazard ratio for mortality was 1.32 (95% CI 1.25-1.40), decreasing to 1.15 (1.09-1.22) after adjusting for pre-existing cardiovascular disease. The hazard ratios for cardiovascular mortality were higher, decreasing from 1.51 (1.37-1.67) to 1.23 (1.11-1.36) after adjusting for pre-existing cardiovascular disease. The hazard ratios decreased with increasing age at diagnosis, although the difference in absolute rate of mortality increased slightly with age. Increased mortality risks were only evident 2 years after diagnosis and increased thereafter.

Conclusions: Patients with Type 2 diabetes have an increased risk of all-cause and cardiovascular mortality compared with non-diabetic comparators, although this is not observable immediately after diagnosis. Age at diagnosis and duration of the disease independently affect absolute and relative mortality risk.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Cardiovascular Diseases / diagnosis
  • Cardiovascular Diseases / mortality*
  • Cause of Death
  • Cohort Studies
  • Databases, Factual
  • Diabetes Mellitus, Type 2 / diagnosis
  • Diabetes Mellitus, Type 2 / mortality*
  • Diabetic Angiopathies / diagnosis
  • Diabetic Angiopathies / mortality*
  • Follow-Up Studies
  • Humans
  • Male
  • Medical Record Linkage
  • Middle Aged
  • Risk Factors
  • Scotland / epidemiology