Spotlight on hypoglycemia

Two recent studies looked at the incidence of hypoglycemia among patients with diabetes around the world, while another offered an intervention to reduce hypoglycemia in patients with impaired awareness of it.

Some recent studies focused on the risk of hypoglycemia from diabetes treatment.

Two studies found that hypoglycemia may be more common than previously reported. The first, published by BMJ Open Diabetes Research & Care on April 24, was based on survey responses from 552 Canadians (83% with type 2 diabetes treated with insulin and/or insulin secretagogues; 17% with type 1 diabetes). Over half (65.2%) of the patients reported experiencing at least one hypoglycemic event, for a crude incidence density of 35.1 events per person-year. Overall incidence was higher among patients with type 1 diabetes, but severe hypoglycemia was reported by a higher percentage of patients with type 2 diabetes. Severe hypoglycemia was reported by 41.8% of respondents, with an average of 2.5 events per person-year. An important aspect of the study was that it included insulin secretagogues, and the results may signal important deficiencies in management of hypoglycemia in patients with type 2 diabetes, the authors said.

The second study, published online by Diabetic Medicine on May 5, was based on data from the Hypoglycemia Assessment Tool, a non-interventional, multi-center, six-month retrospective/four-week prospective investigation. The study included 27,585 adults from 24 countries with type 1 or 2 diabetes treated with insulin. It found most participants were familiar with official definitions of hypoglycemia, but there were regional differences in the use of blood glucose measurements and/or symptoms to define events and reported rates of the condition varied significantly around the world. Overall, 83.4% of patients with type 1 diabetes and 50.8% of those with type 2 diabetes reported a hypoglycemic event in the prospective study period. However, the estimated global annual rates of any hypoglycemia were significantly higher in the prospective period than in the retrospective period for both types of diabetes (rate ratio prospective/retrospective, 1.47 [95% CI, 1.41 to 1.53] for type 1 and 1.20 [95% CI, 1.15 to 1.24] for type 2; P<0.001 for both comparisons). The study authors concluded that under-reporting of hypoglycemia rates in retrospective recall may contribute to global differences in reported rates and that there may be a need to redefine hypoglycemia criteria.

Finally, another study, published online by Diabetes Care on April 16, reported on an intervention to reduce hypoglycemia among 96 British adults with type 1 diabetes and impaired awareness of hypoglycemia. The patients were randomized in a 2 × 2 factorial trial to continuous subcutaneous insulin infusion (CSII) or multiple daily injections (MDI) and real-time continuous glucose monitoring or self-monitoring of blood glucose for 24 weeks. All participants attended a brief education session that focused on identifying personalized factors associated with hypoglycemia and developing individualized plans to prevent hypoglycemia while maintaining glycemic control. At 24 weeks, participants could choose between CSII and MDI; the assignment to a glucose monitoring method continued for 24 months. Results showed significant improvements from baseline in hypoglycemia awareness (Gold score of 3.7 vs. 5.5; P<0.0001), rates of severe hypoglycemia (0.4 episodes per person-year vs. 8.9; P<0.0001), and HbA1c level (7.7% vs. 8.2%; P=0.003), with no significant differences between the interventions.

“This study demonstrates that a brief educational intervention with intensive support over 24 weeks leads to benefits sustained over 24 months in a high-risk cohort with long-standing type 1 diabetes and impaired awareness of hypoglycemia. It confirms that avoiding severe hypoglycemia does not need to be achieved at the expense of higher overall glucose levels,” the study authors said. They noted that the study was limited by baseline hypoglycemia data being based on patient recall and the significant percentage of patients lost to follow-up. Factors potentially affecting generalizability include the patients receiving specialist care and the study design augmenting conventional self-monitoring with targeted postprandial and 4-a.m. testing.