Biopsychobehavioral model of severe hypoglycemia II - Understanding the risk of severe hypoglycemia

OBJECTIVE - To evaluate the clinical/research utility of the biopsychobehav ioral model of severe hypoglycemia in differentiating patients with and wit hout a history of severe hypoglycemia and in predicting occurrence of futur e severe hypoglycemia. RESEARCH DESIGN AND METHODS - A total of 93 adults with type 1 diabetes (me an age 35.8 years, duration of diabetes 16 +/- 10 years, HbA(1) 8.6 +/- 1.8 %), 42 of whom had a recent history of recurrent severe hypoglycemia (SH) a nd 51 who did not (NoSH), used a handheld computer for 70 trials during 1 m onth recording cognitive-motor functioning, symptoms, blood glucose (BG) es timates, judgments concerning self-treatment of BG, actual BG readings, and actual treatment of low BG. For the next 6 months, patients recorded occur rence of severe hypoglycemia. RESULTS - SH patients demonstrated significantly more frequent and extreme low BG readings (low BG index), greater cognitive-motor impairments during hypoglycemia, fewer perceived symptoms of hypoglycemia, and poorer detectio n of hypoglycemia. Sn patients were also less likely to treat their hypogly cemia with glucose and more likely to treat with general foods. Low BG inde x, magnitude of hypoglycemia-impaired ability to do mental subtraction, and awareness of neuroglycopenia, neurogenic symptoms, and hypoglycemia correl ated separately with number of SH episodes in the subsequent 6 months. Howe ver, only low BG index, hypoglycemia-impaired ability to do mental subtract ion, and awareness of hypoglycemia entered into a regression model predicti ng future severe hypoglycemia (R-2 = 0.25, P < 0.001). CONCLUSIONS - Patients with a history of severe hypoglycemia differed on fi ve of the seven steps of the biopsychobehavioral model of severe hypoglycem ia. Helping patients with a recent history of severe hypoglycemia to reduce the frequency of their low-BG events, become more sensitive to early signs of neuroglycopenia and neurogenic symptoms, better recognize occurrence of low BG, and use fast-acting glucose more frequently in the treatment of lo w BG, may reduce occurrence of future severe hypoglycemia.