Relationship between glycemic control and readmission rates in patients hospitalized with congestive heart failure during implementation of hospital-wide initiatives.

Objective: To determine the relationship between inpatient glycemic control and hospital readmission in patients with congestive heart failure (CHF).

Methods: We used an electronic data collection tool to identify patients with a discharge diagnosis of CHF who underwent point-of-care glucose assessments. Timeweighted mean glucose (TWMG), hemoglobin A1c, and glycemic lability index (GLI) served as glycemic indicators, and readmission for CHF was determined at 30 days and between 30 and 90 days.

Results: The analysis included 748 patients. After adjustment for significant covariates, log-transformed increasing TWMG (odds ratio 3.3; P = .03) and log-transformed hemoglobin A1c (odds ratio 5.5; P = .04) were independently associated with higher readmission for CHF between 30 and 90 days, but not by 30 days. Renal disease, African American race, and year of hospital admission were also significantly associated with readmission, but GLI was not. There was no significant difference in TWMG when analyzed on the basis of race or renal status. We noted a decrease in TWMG (P = .004) and a trend for reduction in readmission rates between 30 and 90 days (P = .06) after hospital-wide interventions were implemented to improve glycemic control, but no significant difference was detected in GLI or hypoglycemia.

Conclusion: Increasing glucose exposure, but not glycemic variability, was associated with higher risk of readmission between 30 and 90 days in patients with CHF. Prospective studies are needed to confirm or refute these results.