Association between symptoms of bilateral numbness and/or paresthesia in the feet and postural instability in Japanese patients with diabetes

Abstract

Aim: This study assessed the association between symptoms of bilateral numbness and/or paresthesia in the feet and postural instability in Japanese patients with diabetes. Methods: This cross-sectional study included 303 patients with diabetes, aged 40–88 years, who were referred to an outpatient diabetic clinic between January and July 2013 at Shiga University of Medical Science Hospital. A posturography test was used to evaluate postural sway in patients. Indices of postural sway were the total length and the enveloped area. Analysis of covariance was used to estimate the multivariable-adjusted means of indices of postural sway according to the presence or absence of symptoms of bilateral numbness and/or paresthesia in the feet. Results: Of 303 patients, 35 (11.6 %) had symptoms of bilateral numbness and/or paresthesia in the feet. After adjustment for age, sex, diabetic retinopathy, regular exercise, body mass index, hemoglobin A1c level, and quadriceps’ strength, patients with symptoms had higher levels of postural sway length and an enveloped area in the posturography test than those without symptoms. In addition, we observed similar results when we analyzed 234 patients aged ≥60 years. Conclusions: Our findings suggest that patients who had symptoms of bilateral numbness and/or paresthesia in the feet may have more postural instability than those without symptoms.