Effects of Preoperative HbA1c Levels on the Postoperative Outcomes of Coronary Artery Disease Surgical Treatment in Patients with Diabetes Mellitus and Nondiabetic Patients: A Systematic Review and Meta-Analysis
Table 4
Quality of evidence of ten outcomes in diabetic patients after cardiac surgery.
Quality assessment
Effect size
Quality of the evidence (GRADE)
No. of studies (sample size)
Study design
Risk of bias
Inconsistency
Indirectness
Imprecision
Publication bias
Rating up factor
Mortality: Higher HbA1c level vs lower HbA1c level (preoperative)
19 (24092)
Cohort study
Seriousa
Not serious
Not serious
Not serious
Undetected
No
OR 1.06 [0.88, 1.26]
⊕⊕⊕Ο
Moderate
Surgical site infection: higher HbA1c level vs. lower HbA1c level (preoperative)
12 (9437)
Cohort study
Seriousa
Not serious
Not serious
Not serious
Undetected
No
OR 2.94 [2.18, 3.98]
⊕⊕⊕Ο
Moderate
Stroke: higher HbA1c level vs. lower HbA1c level (preoperative)
10 (5381)
Cohort study
Seriousa
Not serious
Not serious
Not serious
Undetected
No
OR 1.49 [0.94, 2.37]
⊕⊕⊕Ο
Moderate
Renal failure: higher HbA1c level vs lower HbA1c level (preoperative)
9 (5081)
Cohort study
Seriousa
Seriousb
Not serious
Not serious
Undetected
No
OR 1.63 [1.13, 2.33]
⊕⊕ΟΟ
Low
Myocardial infarction: higher HbA1c level vs. lower HbA1c level (preoperative)
9 (5848)
Cohort study
Seriousa
Not serious
Not serious
Not serious
Undetected
No
OR 1.69 [1.16, 2.47]
⊕⊕⊕Ο
Moderate
Hospital stay: higher HbA1c level vs. lower HbA1c level (preoperative)
6 (2202)
Cohort study
Seriousa
Seriousb
Not serious
Not serious
Undetected
No
MD 1.08 [0.46, 1.71]
⊕⊕ΟΟ
Low
Atrial fibrillation: higher HbA1c level vs. lower HbA1c level (preoperative)
5 (3002)
Cohort study
Seriousa
Seriousb
Not serious
Not serious
Undetected
No
OR 0.94 [0.67, 1.33]
⊕⊕ΟΟ
Low
Length of ICU stay: higher HbA1c level vs. lower HbA1c level (preoperative)
4 (1121)
Cohort study
Seriousa
Not serious
Not serious
Not serious
Undetected
No
OR 0.20 [-0.14, 0.55]
⊕⊕⊕Ο
Moderate
Sepsis: higher HbA1c level vs. lower HbA1c level (preoperative)
4 (1492)
Cohort study
Seriousa
Not serious
Not serious
Seriousc
Undetected
No
OR 2.49 [0.99, 6.25]
⊕⊕ΟΟ
Low
High: we are very confident that the true effect lies close to that of the estimate of the effect; moderate: we are moderately confident in the effect estimate—the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different; low: our confidence in the effect estimate is limited—the true effect may be substantially different from the estimate of the effect; very low: we have very little confidence in the effect estimate—the true effect is likely to be substantially different from the estimate of effect. aThe poor quality of included studies in the independent blind assessment of outcomes and inadequate follow-up time. bSerious inconsistency for the scattered 95% CI. cWide confidence intervals, serious imprecision.
