Impact of diabetes and its treatment on cognitive function among adolescents who participated in the Diabetes Control and Complications Trial.

OBJECTIVE: The purpose of this study was to evaluate whether severe hypoglycemia or intensive therapy affects cognitive performance over time in a subgroup of patients who were aged 13-19 years at entry in the Diabetes Control and Complications Trial (DCCT). RESEARCH DESIGN AND METHODS: This was a longitudinal study involving 249 patients with type 1 diabetes who were between 13 and 19 years old when they were randomly assigned in the DCCT. Scores on a comprehensive battery of cognitive tests obtained during the Epidemiology of Diabetes Interventions and Complications follow-up study, approximately 18 years later, were compared with baseline performance. We assessed the effects of the original DCCT treatment group assignment, mean A1C values, and frequency of severe hypoglycemic events on eight domains of cognition. RESULTS: There were a total of 294 reported episodes of coma or seizure. Neither frequency of hypoglycemia nor previous treatment group was associated with decline on any cognitive domain. As in a previous analysis of the entire study cohort, higher A1C values were associated with declines in the psychomotor and mental efficiency domain (P < 0.01); however, the previous finding of improved motor speed with lower A1C values was not replicated in this subgroup analysis. CONCLUSIONS: Despite relatively high rates of severe hypoglycemia, cognitive function did not decline over an extended period of time in the youngest cohort of patients with type 1 diabetes.

Postpartum adiponectin concentration, insulin resistance and metabolic abnormalities among women with pregnancy-induced disturbances.

The authors compared postpartum adiponectin levels among women with prior pregnancy-induced disturbances and assessed their association with homeostasis model assessment for insulin resistance (HOMA-IR), the metabolic syndrome (MS), and the Framingham risk score (FRS). Women delivering in 1998 through 2001 and who had gestational diabetes mellitus (n=22), gestational hypertension (n=32), or preeclampsia (n=34) were examined 1 to 2 years after delivery and were grouped-matched to controls (n=29) by age and prepregnancy body mass index. HOMA-IR was increased, adiponectin values were decreased, and there was a higher MS prevalence in women with prior gestational diabetes mellitus (all P<.05). Adiponectin levels were inversely related to HOMA-IR (r=-0.45; P<.0001) and FRS (r=-0.25; P=.007), and a significant trend for decreasing adiponectin values with increased number of MS components was noted (P trend <.0001). Adiponectin concentration remained a significant correlate of FRS and MS irrespective of pregnancy history; a concentration <10.5 microg/mL provided the optimal cutoff to distinguish those with or without MS. Thus, a lower postpartum adiponectin concentration identifies women at increased cardiovascular risk regardless of pregnancy history.

Long-term effect of diabetes and its treatment on cognitive function.

BACKGROUND: Long-standing concern about the effects of type 1 diabetes on cognitive ability has increased with the use of therapies designed to bring glucose levels close to the nondiabetic range and the attendant increased risk of severe hypoglycemia. METHODS: A total of 1144 patients with type 1 diabetes enrolled in the Diabetes Control and Complications Trial (DCCT) and its follow-up Epidemiology of Diabetes Interventions and Complications (EDIC) study were examined on entry to the DCCT (at mean age 27 years) and a mean of 18 years later with the same comprehensive battery of cognitive tests. Glycated hemoglobin levels were measured and the frequency of severe hypoglycemic events leading to coma or seizures was recorded during the follow-up period. We assessed the effects of original DCCT treatment-group assignment, mean glycated hemoglobin values, and frequency of hypoglycemic events on measures of cognitive ability, with adjustment for age at baseline, sex, years of education, length of follow-up, visual acuity, self-reported sensory loss due to peripheral neuropathy, and (to control for the effects of practice) the number of cognitive tests taken in the interval since the start of the DCCT. RESULTS: Forty percent of the cohort reported having had at least one hypoglycemic coma or seizure. Neither frequency of severe hypoglycemia nor previous treatment-group assignment was associated with decline in any cognitive domain. Higher glycated hemoglobin values were associated with moderate declines in motor speed (P=0.001) and psychomotor efficiency (P<0.001), but no other cognitive domain was affected. CONCLUSIONS: No evidence of substantial long-term declines in cognitive function was found in a large group of patients with type 1 diabetes who were carefully followed for an average of 18 years, despite relatively high rates of recurrent severe hypoglycemia. (ClinicalTrials.gov number, NCT00360893.)