(HealthDay News) — Time-updated HbA1c variables have a stronger association with myocardial infarction (MI) than baseline HbA1c, according to a study published in Diabetes Care.
Marita Olsson, PhD, from R&D AstraZeneca in Mölndal, Sweden, and colleagues examined the risk for MI by impaired glycemic control in a cohort of patients with type 2 diabetes, diagnosed between 1995 and 2001, using data from the Clinical Practice Research Data (CPRD) Link in the United Kingdom (101,799 participants).
Participants were divided into an early cohort (diagnosed from 1997 to 2004) and a recent cohort (diagnosed from 2004 to 2011). The correlation between three HbA1c metrics and MI was examined.
The researchers found that the risk increase for MI per 1% increase in HbA1c was higher for updated latest and updated mean HbA1c than for baseline HbA1c (1.11 and 1.15, respectively, vs. 1.05), in the overall cohort. The corresponding risk estimates were greater in the early vs. the recent cohort.
In the recent, but not the early, cohort the updated latest variable showed an increased risk for HbA1c less than 6% relative category 6% to 7% (HRs=1.23 [95% CI, 1.08-1.40] and 1.01 [95% CI, 0.84-1.22], respectively).
“The two time-updated HbA1c variables show stronger associations with risk of MI than baseline HbA1c, and the association between HbA1c and risk of MI has decreased over time,” the researchers wrote.
Several authors disclosed financial ties to pharmaceutical companies, including AstraZeneca, which funded access to the CRPD database.