Hoog HbA1c vergroot risico op MI bij diabetes

High HbA1c increases MI risk in diabetics

Researchers report that poor blood glucose control increases the risk for myocardial infarction (MI) irrespective of other cardiovascular (CV) risk factors, including diabetes, and patient ethnicity.

"Every 1% increment [in glycated hemoglobin (HbA1c)] independently predicts a 19% higher odd of MI after accounting for other MI risk factors including diabetes," report Hertzel Gerstein (McMaster University, Hamilton, Ontario, Canada) and team.

They say that their findings show that "dysglycemia increases CV risk through a mechanism that appears to be independent of these other CV risk factors, and that this mechanism is relevant with and without a history of diabetes, and operates on a global level."

As reported in the journal Diabetologia, the researchers measured the HbA1c levels of 15,780 participants from 52 countries, with (n=6761) and without a history of MI (n=9019).

Of these patients, 12.6% (1993) had diabetes and 87.4% (13,787) did not.

The findings showed that patients with a previous history of MI had a higher mean HbA1c level than those with no MI history, at 6.15% versus 5.85%, respectively.

After adjustment for MI risk factors such as diabetes and hypertension, patients in the highest HbA1c quintile (HbA1c ≥6.12%) had a 1.55-fold increased relative risk for MI compared with those in the lowest quintile (HbA1c <5.4%).

Further analysis of HbA1c as a continuous variable revealed a similar pattern, even after adjusting for diabetes status, age, and gender.

Furthermore subgroup analyses showed the same positive association between HbA1c and MI, with the highest increases in MI risk observed among those of a young age (less than 65 years for males, and less than 55 years for females), those without hypertension or diabetes, and those of specific ethnicities such as European and South Asian.

Gerstein et al conclude: "These findings clearly show that dysglycemia as measured by HbA1c level in people with or without a history of diabetes is a strong, independent CV risk factor throughout different regions of the world and ethnicities."

They add: "Strategies that reduce the prevalence of dysglycemia by preventing or reversing diabetes, or by slowing the rise of HbA1c with time may reduce the global burden of MI."

Diabetologia 2010; Advance online publication