HbA1c Minimally Adds to CVD Risk Prediction in Prediabetes
Classical risk factors explain most of the increased risk for CVD associated with HbA1c in prediabetes
FRIDAY, Dec. 20, 2019 (HealthDay News) -- For individuals with prediabetes, hemoglobin A1c (HbA1c) minimally adds to cardiovascular disease (CVD) risk prediction, according to a study published online Dec. 18 in Diabetes Care.
Claire Welsh, Ph.D., from the Institute of Cardiovascular & Medical Sciences at the University of Glasgow in the United Kingdom, and colleagues examined whether HbA1c affects CVD risk assessment among 358,275 U.K. Biobank participants without baseline CVD or known diabetes. The associations between HbA1c and CVD were examined while adjusting for classical risk factors.
The researchers found that during 8.9 years, incident fatal or nonfatal CVD, as defined in the QRISK3 prediction model, occurred in 12,894 participants. Of the participants, 3.3 and 0.7 percent had prediabetes and undiagnosed diabetes, respectively. Compared with the reference group (HbA1c, <6.0 percent), those with prediabetes (6.0 to 6.4 percent) and undiagnosed diabetes (HbA1c, ≥6.5 percent) had higher CVD risk in unadjusted models (hazard ratios, 1.83 and 2.26, respectively). The hazard ratios were attenuated to 1.11 and 1.20, respectively, after adjustment for classical risk factors. A small improvement in discrimination was yielded by adding HbA1c to the QRISK3 CVD risk prediction model (C-index increase of 0.0004). There was no improvement in the net reclassification index.
"In this very large well-phenotyped cohort with central laboratory assessment of HbA1c, we show that HbA1c minimally improves CVD risk prediction in patients without diabetes," the authors write.
Two authors disclosed financial ties to the pharmaceutical industry.