Spotlight on inpatient diabetes care
Recent studies looked at the use of continuous glucose monitoring and metformin in the hospital.
Several recent studies focused on care for hospitalized patients with diabetes.
First, a trial published by Diabetes Care on Jan. 31 assessed the effects of using continuous glucose monitoring (CGM) to titrate insulin for hospital patients. Researchers randomized 166 medical inpatients to insulin titration based on either point-of-care glucose testing or CGM. The CGM arm had a higher median time in the target glucose range of 3.9 to 10.0 mmol/L (70 to 180 mg/dL) at 77.6% versus 62.7% (P<0.001). The CGM patients also spent less time above the target range (21.1% vs. 36.5%) and had fewer prolonged hypoglycemic events (incidence rate ratio, 0.13 [95% CI, 0.04 to 0.46]; P=0.001). The study authors concluded that in-hospital CGM use significantly increased time in range while also having a positive effect on glycemic variability, hypoglycemic events, insulin usage, and in-hospital complications. “Diabetes-competent and CGM-educated personnel (e.g., in-hospital diabetes teams) and insulin titration algorithms are most likely necessary to achieve optimal clinical and glycemic effects of CGM in hospitalized patients with type 2 diabetes,” they wrote.
Looking at the same topic, a systematic review, published by the Journal of Clinical Endocrinology & Metabolism on Feb. 7, found nine different protocols in the literature for inpatient CGM-based insulin titration. Six protocols recommended a weight-based basal-bolus insulin regimen, and titration was typically done daily, based on either clinical discretion or clearly defined protocols. Protocols used both CGM and fingerstick testing. In five protocols, specifically trained staff oversaw insulin management. The review also found that CGM alarm settings varied widely, with hyperglycemia alarm thresholds between 13.9 mmol/L (250 mg/dL) and 22.2 mmol/L (400 mg/dL) and hypoglycemia alarms between 3.9 mmol/L (70 mg/dL) and 5 mmol/L (90 mg/dL). The observed variation in protocols highlights the need for standardization of this aspect of care, the study authors said. “The absence of standardised CGM-based insulin titration protocols may help explain why most [randomized controlled trials] with CGM have not demonstrated improvement in glycaemic outcomes compared to finger prick glucose testing,” they wrote.
Another study, published by the Journal of General Internal Medicine on Feb. 3, looked at the effects of continuing patients' outpatient metformin prescriptions during hospitalization. Researchers propensity-matched 67,162 hospitalizations in Veterans Administration facilities by whether metformin was continued during hospitalization or not. Within 90 days of hospital discharge, those who received metformin had lower risk of hypoglycemia (1.5% vs. 1.8%; odds ratio [OR], 0.83 [95% CI, 0.73 to 0.93]; P=0.003), readmission (29.4% vs. 30.6%; OR, 0.96 [95% CI, 0.92 to 1.00]; P=0.03), mortality (6.4% vs. 7.4%; OR, 0.86 [95% CI, 0.80 to 0.92]; P<0.001) and insulin prescription at discharge (18.5% vs. 20.3%; OR, 0.89 [95% CI, 0.84 to 0.95]; P<0.001). “These findings question clinical guideline recommendations to hold metformin during hospitalization, and continuation of metformin should be considered for patients without contraindications given the low risk of adverse events and potential for improved outcomes at hospital discharge,” wrote the study authors.
Finally, a study published by the Journal of General Internal Medicine on Jan. 22 analyzed why medical residents discontinue metformin on admission. All 184 of the first- through third-year residents of an internal medicine program were asked if they would continue metformin for a patient admitted for uncomplicated cellulitis with no contraindications to metformin. In total, 68 residents responded, and 66% said they would discontinue metformin on admission. The most frequently reported concerns about continuing metformin were deviation from the practice of peers, disagreement with their attending, and risk of lactic acidosis. In general, 53% said they routinely or always discontinue metformin upon admission even in the absence of contraindications. Asked if metformin can cause lactic acidosis in the absence of contraindications, one respondent said yes, 50% said they were unsure, and 49% said no. “The barriers to inpatient metformin prescription can serve as a useful template for residents or their training programs when the opportunity arises to enact change that disrupts the status quo,” the study authors said.