Impaired Cortisol and Growth Hormone Counterregulatory Responses among Severe Hypoglycemic Patients with Type 2 Diabetes Mellitus

BACKGROUND: Elevated levels of cortisol and growth hormone are critical counterregulatory responses to severe hypoglycemia. However, the proportion and clinical characteristics of patients with type 2 diabetes mellitus (DM) who fail to show appropriate cortisol and/or growth hormone secretion in response to severe hypoglycemia have not been investigated. METHODS: We measured plasma cortisol and growth hormone levels in type 2 DM patients with severe hypoglycemia who visited the emergency department between 2006 and 2015. RESULTS: Of 112 hypoglycemic patients, 23 (20.5%) had an impaired cortisol response (<18 µg/dL) and 82 patients (73.2%) had an impaired growth hormone response (<5 ng/mL). Nineteen patients (17.0%) had impaired responses to both cortisol and growth hormone. The patients with impaired responses of cortisol, growth hormone, and both hormones were significantly older and more likely to be female, and had higher admission rates, lower growth hormone levels, and lower adrenocorticotropic hormone levels than the patients with a normal hormonal response. Multivariate logistic regression analysis indicated that an impaired growth hormone response was significantly associated with advanced age, shorter DM duration, a higher admission rate, and a higher body mass index (BMI). An impaired cortisol response was significantly associated with growth hormone levels. Patients with an impaired growth hormone response had higher admission rates than patients with a normal response. CONCLUSION: A considerable number of type 2 DM patients had impaired cortisol and/or growth hormone responses to severe hypoglycemia. Advanced age, shorter DM duration, and higher BMI were independently associated with an abnormal growth hormone response.