Vibratory thresholds correlation with systolic blood pressure in diabetic women

Previous studies have suggested a potential association of elevated blood pressure (BP) and the development of diabetic neuropathy for individuals with insulin-dependent diabetes mellitus. In this study, we examined an association between BP and vibratory thresholds (assessment modality of large sensory nerve fiber function) for 33 participants with non-insulin-dependent diabetes mellitus. There were 19 women and 14 men aged 58 +/- 7 (mean +/- SD) years, with diabetes duration of 7 +/- 6 years and a body mass index of 29 +/- 5 kg/m2. None of the individuals were taking any medications that lower BP and all were negative for the presence of microalbuminuria. Vibratory thresholds were determined at three visits using a two-alternative, forced-choice procedure. BP was assessed by 24-h ambulatory BP monitoring. As expected, vibratory thresholds were higher for men than for women (6.3 +/- 4 v 4.2 +/- 3 vibration units) but there was no statistical difference after controlling for height. In multivariate analyses with vibratory thresholds as the dependent variable, duration of diabetes (P < 0.01), age (P < .01) and systolic BP (SBP) (P < .01) explained approximately 70% of the overall variability of the gender-specific (ie, female) model. The variability was similar (ie, 70% to 73%) no matter which SBP measure was available for modeling. In terms of diastolic blood pressure (DBP) measures, only the percentage of abnormal readings (ie, > 90 mm Hg) for day DBP was found to be independently associated with vibratory thresholds for women. The association of BP and large sensory nerve fiber dysfunction for nonnephropathic diabetic women found in this cross-sectional study warrants further investigation.