Contributors to Mortality in High-Risk Diabetic Patients in the Diabetes Heart Study

  1. Donald W. Bowden1,2,3
  1. 1Center for Diabetes Research, Wake Forest School of Medicine, Winston-Salem, NC
  2. 2Center for Genomics and Personalized Medicine Research, Wake Forest School of Medicine, Winston-Salem, NC
  3. 3Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC
  4. 4Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, NC
  5. 5Department of Internal Medicine - Nephrology, Wake Forest School of Medicine, Winston-Salem, NC
  6. 6Department of Internal Medicine - Cardiology, Wake Forest School of Medicine, Winston-Salem, NC
  7. 7Department of Family and Preventive Medicine, University of California, San Diego, CA
  8. 8Department of Radiologic Sciences, Wake Forest School of Medicine, Winston-Salem, NC
  1. Corresponding author: Donald W. Bowden, dbowden{at}wakehealth.edu.

Abstract

OBJECTIVE Not all individuals with type 2 diabetes and high coronary artery calcified plaque (CAC) experience the same risk for adverse outcomes. This study examined a subset of high-risk individuals based on CAC >1,000 mg (using a total mass score) and evaluated whether differences in a range of modifiable cardiovascular disease (CVD) risk factors provided further insights into risk for mortality.

RESEARCH DESIGN AND METHODS We assessed contributors to all-cause mortality among 371 European American individuals with type 2 diabetes and CAC >1,000 from the Diabetes Heart Study (DHS) after 8.2 ± 3.0 years (mean ± SD) of follow-up. Differences in known CVD risk factors, including modifiable CVD risk factors, were compared between living (n = 218) and deceased (n = 153) participants. Cox proportional hazards regression models were used to quantify risk for all-cause mortality.

RESULTS Deceased participants had a longer duration of type 2 diabetes (P = 0.02) and reduced use of cholesterol-lowering medications (P = 0.004). Adjusted analyses revealed that vascular calcified plaque scores were associated with increased risk for mortality (hazard ratio 1.31–1.63; 3.89 × 10−5 < P < 0.03). Higher HbA1c, lipids, and C-reactive protein and reduced kidney function also were associated with a 1.1- to 1.5-fold increased risk for mortality (3.45 × 10−6 < P < 0.03) after adjusting for confounding factors.

CONCLUSIONS Even in this high-risk group, vascular calcification and known CVD risk factors provide useful information for ongoing assessment. The use of cholesterol-lowering medication seemed to be protective for mortality.

  • Received January 10, 2014.
  • Accepted June 1, 2014.

This Article

  1. Diabetes Care