Risk of Cardiovascular Events in Patients With Diabetes Mellitus on ß-Blockers.

Although the use of ß-blockers may help in achieving maximum effects of intensive glycemic control because of a decrease in the adverse effects after severe hypoglycemia, they pose a potential risk for the occurrence of severe hypoglycemia. This study aimed to evaluate whether the use of ß-blockers is effective in patients with diabetes mellitus and whether its use is associated with the occurrence of severe hypoglycemia. Using the ACCORD trial (Action to Control Cardiovascular Risk in Diabetes) data, we performed Cox proportional hazards analyses with a propensity score adjustment. The primary outcome was the first occurrence of a cardiovascular event during the study period, which included nonfatal myocardial infarction, unstable angina, nonfatal stroke, and cardiovascular death. The mean follow-up periods (±SD) were 4.6±1.6 years in patients on ß-blockers (n=2527) and 4.7±1.6 years in those not on ß-blockers (n=2527). The cardiovascular event rate was significantly higher in patients on ß-blockers than in those not on ß-blockers (hazard ratio, 1.46; 95% confidence interval, 1.24-1.72; P<0.001). In patients with coronary heart disease or heart failure, the cumulative event rate for cardiovascular events was also significantly higher in those on ß-blockers than in those not on ß-blockers (hazard ratio, 1.27; 95% confidence interval, 1.02-1.60; P=0.03). The incidence of severe hypoglycemia was significantly higher in patients on ß-blockers than in those not on ß-blockers (hazard ratio, 1.30; 95% confidence interval, 1.03-1.64; P=0.02). In conclusion, the use of ß-blockers in patients with diabetes mellitus was associated with an increased risk for cardiovascular events.

Possible discrepancy of HbA1c values and its assessment among patients with chronic renal failure, hemodialysis and other diseases.

BACKGROUND: Glycated hemoglobin (HbA1c) and glycated albumin (GA) are frequently used as glycemic control markers. However, these markers are influenced by alterations in hemoglobin and albumin metabolism. Thus, conditions such as anemia, chronic renal failure, hypersplenism, chronic liver diseases, hyperthyroidism, hypoalbuminemia, and pregnancy need to be considered when interpreting HbA1c or GA values. Using data from patients with normal albumin and hemoglobin metabolism, we previously established a linear regression equation describing the GA value versus the HbA1c value to calculate an extrapolated HbA1c (eHbA1c) value for the accurate evaluation of glycemic control. In this study, we investigated the difference between the measured HbA1c and the eHbA1c values for patients with various conditions. METHODS: Data sets for a total of 2461 occasions were obtained from 731 patients whose HbA1c and GA values were simultaneously measured. We excluded patients with missing data or changeable HbA1c levels, and patients who had received transfusions or steroids within the previous 3 months. Finally, we included 44 patients with chronic renal failure (CRF), 10 patients who were undergoing hemodialysis (HD), 7 patients with hematological malignancies and a hemoglobin level of less than 10 g/dL (HM), and 12 patients with chronic liver diseases (CLD). RESULTS: In all the groups, the eHbA1c values were significantly higher than the measured HbA1c values. The median difference was 0.75 % (95 % CI 0.40-1.10 %, P for the difference is <0.001) in the CRF group, 0.80 % (95 % CI 0.30-1.65 %, P for the difference is 0.041) in the HD group, 0.90 % (95 % CI 0.90-1.30 %, P for the difference is 0.028) in the HM group, and 0.85 % (95 % CI 0.40-1.50 %, P for the difference is 0.009) in the CLD group. CONCLUSIONS: We found that the measured HbA1c values were lower than the eHbA1c values in each of the groups.