A PROSPECTIVE-STUDY IDENTIFYING RISK-FACTORS FOR DISCONTINUANCE OF INSULIN PUMP THERAPY

OBJECTIVE- To identify characteristics of adult patients at baseline a ssociated with duration of subsequent, continuous, subcutaneous infusi on of insulin treatment (pump therapy) of type I diabetes. RESEARCH DE SIGN AND METHODS- For 6 wk, patients followed a standardized conventio nal therapy and kept a record of insulin dosages, capillary blood gluc ose concentrations, and symptomatic hypoglycemia. They were then hospi talized. Additional baseline data were obtained and pump therapy was s tarted. Survival analysis was used to determine the relationship betwe en baseline independent variables or risk factors and duration of pump therapy, which is the dependent variable. RESULTS- Of the 68 particip ants, 33 (49%) terminated pump therapy after an average of 9.9 mo of t reatment. Two models (each P < 0.00005) were developed that exhibited a high degree of consistency. Of the 6 variables, 5 were common to bot h models (HbA,, autonomic neuropathy, mean amplitude of glycemic excur sions, frequency of symptoms of hypoglycemia when blood glucose was < 70 mg/dl, and erythema at injection sites). The sixth variable in mode l 1 (insulin dosage) was replaced in model 2 by a variable, Adult Self -Efficacy for Diabetes, which was obtained on the 33 more recently enr olled patients; this variable related to patient perceptions of self-c are behaviors. CONCLUSIONS- We found that, at baseline, the presence o f a high concentration of HbA1 and a low estimation by the patient of their ability to treat the portend failure of insulin pump therapy as evidenced by its discontinuation. This effect is accentuated when clin ical evidence of autonomic neuropathy is observed. These findings offe r guidance in selecting patients with type I diabetes for insulin pump therapy.