November 1, 2003Diabetes Care172 citationsOpen Access
Influence of Autonomic Nervous System Dysfunction on the Development of Type 2 Diabetes
Structured PICO
Does slow heart rate recovery predict increases in insulin and glucose and the development of type 2 diabetes in healthy young adults?
P
Population
3,295 healthy adults aged 18-30 years in the Coronary Artery Risk Development in Young Adults (CARDIA) study
I
Intervention
Slow heart rate recovery (HRR) following cessation of an exercise treadmill test (e.g., quartile 1 or <42 bpm)
C
Comparator
Faster heart rate recovery (e.g., quartile 4 or >42 bpm)
O
Outcome
Increases in insulin and glucose over time and the development of type 2 diabetes (glucose ≥7 mmol/l or use of diabetes control medication) at 7-, 10-, and 15-year examinationssurrogate
Autonomic dysfunction, indicated by slow heart rate recovery, combined with poor physical fitness, is associated with early glucose dysmetabolism and an increased risk of developing type 2 diabetes.
Abstract
OBJECTIVE: We investigated whether autonomic nervous system dysfunction, estimated by slow heart rate recovery (HRR) following cessation of an exercise treadmill test, was associated with increases in insulin and glucose over time and the development of type 2 diabetes. RESEARCH DESIGN AND METHODS: Maximal exercise tests were performed by 3295 healthy adults aged 18-30 years in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Repeat measurements of insulin and glucose collected at 7-, 10-, and 15-year examinations were compared by quartiles of HRR (maximum heart rate minus heart rate 2 min after cessation of the test). Incident diabetes was identified at any follow-up examination as glucose >or=7 mmol/l or the use of diabetes control medication. RESULTS: Among participants who did not develop diabetes, fasting insulin concentrations increased from baseline to year 15. Following adjustment (for age, race, sex, smoking status, and BMI), participants with the slowest HRR (quartile 1) had higher fasting insulin at each examination than participants with faster HRR (e.g., year 15 examination: 88.1 vs. 81.3 pmol/l for quartile 1 vs. quartile 4, respectively, P = 0.05). Glucose did not differ by quartile of HRR at any examination. Among participants with poor fitness, the risk of developing diabetes (n = 98) was 3.4-fold greater (95% CI 1.5-8.0) when HRR was 42 bpm. This persisted following adjustment for baseline insulin. CONCLUSIONS: Autonomic dysfunction, in combination with poor physical fitness, may be a mechanism associated with early glucose dysmetabolism and the development of diabetes.