IMPACT OF OBESITY ON NEUROPATHIC LATE COMPLICATIONS IN NIDDM

OBJECTIVE- This cross-sectional study was aimed to investigate the iso lated influence of obesity on peripheral sensorimotor and autonomic ne uropathy in patients with long-term non-insulin-dependent diabetes mel litus (NIDDM). RESEARCH DESIGN IND METHODS- Ninety-one long-term NIDDM patients with a mean duration of 13.6 +/- 1.0 years and a mean age of 60.4 +/- 1.0 years were divided into two groups according to their bo dy mass index (BMI) (lean with a BMI <26.5: n = 41, age = 58.6 +/- 1.7 years, BMI = 23.7 +/- 0.3 kg/m(2); and obese with a BMI greater than or equal to 26.5: n = 50, age = 61.9 +/- 1.2 years, BMI = 30.5 +/- 0.5 kg/m(2)). The two groups were not different in age, duration, gender, current parameters of glycemic control, number of smokers, cholestero l, triglycerides, and systolic and diastolic blood pressure. Neuropath ic late complications were scrutinized by a standardized clinical exam ination that delivers a neuropathy score, pupillary autonomic neuropat hy assessed by pupillometry, and cardiovascular autonomic neuropathy u sing a standardized test battery.RESULTS - One-way analysis of varianc e revealed that obese patients had poor results in the clinical neurop athy test (overall score in obese vs. lean: 71.1 +/- 2.9 vs. 80.6 +/- 3.0 points, 2P = 0.0266; 100 points were absolutely normal). This was particularly true for the discrimination perception (obese vs. lean: 6 7.0 +/- 4.0 vs. 81.7 +/- 3.3 points, 2P = 0.0073) and the reflex statu s (obese vs. lean: 57.4 +/- 4.0 vs. 71.8 +/- 4.3 points, 2P = 0.0164). Furthermore, obese patients had a poor result in the respiratory sinu s arrhythmia (RSA) test, one of six autonomic function tests (RSA: obe se vs. lean in average RSA percentile: 36.9 +/- 4.9 vs. 54.0 +/- 5.9%, 2P = 0.0264). CONCLUSIONS - Obesity influences sensorimotor and auton omic neuropathic late complications. The poor result in RSA in obesity may indicate an interrelation between pathogenesis of obesity and dis orders of the respiratory and heart rhythm-generating control centers in the brain stem. Moreover, it could be due to intrathoracic fat depo sits that alter lung mobility. Body mass control may be an important a pproach to reduce neuropathic complications. Beyond that, it seems nec essary to control for body mass when comparing neuropathy in two group s of patients with NIDDM.