Cross‐sectional survey of diabetic neuropathy in Kanagawa and clinical significance of a touch test using tissue paper

Aims/Introduction: The prevalence of diabetes mellitus is increasing rapidly in Japan, and diabetic neuropathy is a major factor decreasing diabetic patients’ quality of life, as well as a risk factor for sudden death. The present study aimed to determine the prevalence of diabetic neuropathy and raise awareness about it among patients and their physicians. Materials and Methods: Diabetic outpatients (N = 5077) at 249 medical institutions within Kanagawa Prefecture, Japan, were surveyed by questionnaire and underwent foot examinations. The questionnaire included 10 questions about sensory abnormalities of both feet, muscle cramps and autonomic symptoms. Foot examinations included testing for vibratory perception of the medial malleolus, Achilles tendon reflexes and touch sensation of the bottom of the great toe using tissue paper. Results: Of the 5077 patients surveyed, 70.4% reported symptoms. Overall, 75.4% of the patients underwent vibratory perception testing, of whom 44.9% had abnormal thresholds (≤10 s). On the tissue paper touch test, performed in 94.6% of patients, 11.9% had no touch sensation. Of the 2803 type 2 diabetic patients with known background factors who underwent foot examinations, 49.4% had diabetic neuropathy. There was a high prevalence of diabetic neuropathy (36.1%) in patients with <5‐year history. Of the patients with no touch sensation on the tissue paper test, 81.3% had diabetic neuropathy. Conclusions: The present study identified the prevalence of diabetic neuropathy in Kanagawa Prefecture. The tissue paper test is a simple and excellent method of evaluating decreased superficial sensation that can help evaluate the severity of diabetic neuropathy. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00174.x, 2011)