Postmeal, rather than premeal, insulin linked with less hypoglycemia among inpatients

A hospital-wide transition to postprandial nutritional insulin administration significantly reduced hypoglycemia rates without increasing severe hyperglycemia among inpatients, research shows.

Investigators at Johns Hopkins Howard County Medical Center in Maryland changed their policy on June 28, 2019, to shift timing of nutritional insulin from premeal administration to administration after at least 50% of the meal was consumed. They then evaluated the impact by comparing adult inpatients who received nutritional insulin preintervention (September 2018 to June 27, 2019), immediately postintervention (July 2019 to February 2020), or distantly postintervention (September 2022 to August 2023), a total of 1,948, 1,751, and 3,244 patient-days, respectively.

Hypoglycemia was defined as glucose levels at or below 70 mg/dL (3.9 mmol/L), moderate hypoglycemia as levels less than 54 mg/dL (3.0 mmol/L), severe hypoglycemia as levels at or below 40 mg/dL (2.2 mmol/L), and severe hyperglycemia as levels of 300 mg/dL (16.7 mmol/L) or higher. On average, patients were older than age 60 years, had type 2 diabetes, and had a body mass index of at least 30 kg/m². The mean HbA1c level in each cohort was greater than 9%. Findings were published by Diabetes Research and Clinical Practice on July 15.

After adjustment, the risk of developing any hypoglycemia and severe hypoglycemia significantly decreased over time (P=0.001 and P=0.009, respectively). Patients in the distant postintervention group had decreased risk of severe hypoglycemia (odds ratio [OR], 0.44 [95% CI, 0.24 to 0.82]; P=0.009) and any hypoglycemia (OR, 0.71 [95% CI, 0.57 to 0.87]; P=0.001). Daily average glucose level did increase over the time periods (P=0.003), but there were no significant differences in rates of severe hyperglycemia (P=0.10) or length of stay (P=0.74).

The study was carried out at a nonacademic community hospital, so the findings may not be generalizable to other settings. An additional limitation is that glycemia was based on intermittent point-of-care or serum glucose measurements as opposed to continuous glucose monitoring, and episodes of hypoglycemia or severe hyperglycemia may have been missed.

Although there was a gradual rise in daily mean glucose over time, “it is promising that the incidence of severe hyperglycemia was not significantly different across the three time periods,” the authors wrote. Overall, results suggest “a promising strategy for improving patient safety, but further prospective randomized controlled trials are warranted to confirm these findings,” they concluded.