Prognostic significance of hemoglobin A1c level in patients hospitalized with coronary artery disease. A systematic review and meta-analysis

Abstract

BackgroundThe prognostic value of hemoglobin A1c (HbA1c) in coronary artery disease (CAD) remains controversial. Herein, we conducted a systematic review to quantify the association between elevated HbA1c levels and all-cause mortality among patients hospitalized with CAD.MethodsA systematic search of electronic databases (PubMed, EMBASE, OVID, Web of Science, The Cochrane Library) for studies published from 1970 to May 2011 was performed. Cohort, case-control studies, and randomized controlled trials that examined the effect of HbA1c on all-cause mortality were included.ResultsTwenty studies met final inclusion criteria (total n = 13, 224). From the pooled analyses, elevated HbA1c level was significantly associated with increased short-term (OR 2.32, 95% CI, 1.61 to 3.35) and long-term (OR 1.54, 95% CI, 1.23 to 1.94) mortality risk. Subgroup analyses suggested elevated HbA1c level predicted higher mortality risk in patients without diabetes (OR 1.84, 95% CI, 1.51 to 2.24). In contrast, in patients with diabetes, elevated HbA1c level was not associated with increased risk of mortality (OR 0.95, 95% CI, 0.70 to 1.28). In a risk-adjusted sensitivity analyses, elevated HbA1c was also associated with a significantly high risk of adjusted mortality in patients without diabetes (adjusted OR 1.49, 95% CI, 1.24 to 1.79), but had a borderline effect in patients with diabetes (adjusted OR 1.05, 95% CI, 1.00 to 1.11).ConclusionsOur findings demonstrate that elevated HbA1c level is an independent risk factor for mortality in CAD patients without diabetes, but not in patients with established diabetes. Prospective studies should further investigate whether glycemic control might improve outcomes in CAD patients without previously diagnosed diabetes.

The Relation Between HbA1c and Cardiovascular Events in Patients With Type 2 Diabetes With and Without Vascular Disease

“…The findings of cohort studies (18)(19)(20)(21)(22) investigating the relation between HbA 1c level and new cardiovascular events in patients with and without type 2 diabetes after cardiac interventions for coronary artery disease are in line with our findings. In these studies (18,21,22).…”

“…In these studies (18,21,22). In the current study, we expand on these findings by showing a consistent relation across different types of vascular disease.…”

Is there any relationship between serum γ-glutamyltransferase levels and premature coronary artery disease?

“…As known, HbA 1c is an indicator of glycemic control over the preceding 2-3 months. It has been revealed as an independent risk factor for cardiovascular events in many studies [19][20][21]. The results we found about HbA 1c are the expected results when these data are taken into consideration.…”

Prognostic value of glycated hemoglobin among patients with ST-segment elevation myocardial infarction: a systematic review and meta-analysis

“…Though many studies have shown the prognostic value of HbA 1c for overall coronary artery disease (CAD) [9], less is known about the role that HbA 1c played in the prognosis of STEMI. Results from previous studies were controversial [3,8,[10][11][12][13][14].…”