Biopsychobehavioral model of risk of severe hypoglycemia - Self-managementbehaviors

OBJECTIVE - To identify self-management antecedents of low blood glucose (B G) (<3.9 mmol/l) that might be easily recognized, treated, or avoided altog ether. RESEARCH DESIGN AND METHODS - Ninety-three adults with type 1 diabetes (age , 35.8 +/- 8 years [mean +/- SD]; duration of diabetes, 17.0 +/- 11 years; daily insulin dose, 0.58 +/- 0.18 U/kg; and HbA(1c), 8.6 +/- 1.8%) were rec ruited to participate in the study. Of the 93 subjects, 42 had a history of severe hypoglycemia (SH), defined as two or more hypoglycemic episodes in the preceding 12 months, and 51 subjects had no history of SH (No-SH) in th e same time period. Before each of 70 BG measurements obtained over a 3-wee k period, subjects used a handheld computer to record whether their most re cent insulin, food, and exercise was more than, less than, or the same as u sual. Associations among self-management behaviors preceding BG readings <3 .9 mmol/l versus those preceding BG readings of 5.6-7.8 mmol/l were determi ned using chi(2) tests, analyses of variance, and logistic regression analy ses. RESULTS - Analysis of 6,425 self-management/self-monitoring of BG events re vealed that the usual amounts of insulin, food, and exercise preceded the e vents 58.3% of the time. No significant differences were observed for chang es in insulin before readings of BG <3.9 mmol/l versus 7.8 < BG > 5.6 mmol/ l, but significantly less food (P < 0.01) was eaten and more exercise (P < 0.001) was performed before the low BG measurement. No interactions between SH and No-SH groups and management behaviors were observed. However, each of the three management variables entered significantly in a logistic model that predicted 61% of all readings of BG <3.9 mmol/l. CONCLUSIONS - Subjects with a history of SH did not report managing their d iabetes differently from those with no such history Specifically, when low BG occurred, the preceding management behaviors, although predictive of low BG, were not different in Sn and No-SH subjects. Overall, self-management behaviors did not distinguish SH from No-SH subjects. Thus, wen though it m ight be beneficial for all patients to review their food and exercise manag ement decisions to reduce their frequency of low BG, an educational interve ntion whose content stresses insulin, food, and exercise would be unlikely by itself to be sufficient to reduce the frequency of SH.