Diabetic polyneuropathy in the elderly. Prevalence and risk factors in two geographic areas of Italy. Italian General Practitioner Study Group (IGPSG).

OBJECTIVE: To assess the prevalence and the risk factors of diabetic polyneuropathy in representative samples of elderly individuals.

PATIENTS: 4191 subjects 55 years and older from two areas of Italy were screened by their general practitioners (GPs) and those positive for neuropathic symptoms were subjected to a standard clinical examinations.

METHODS: The screening questionnaire included a list of clinical conditions possibly causing polyneuropathy, including diabetes. In patients with diabetes, the date of diagnosis, the most recent fasting and post-prandial blood glucose value and glycosylated hemoglobin were sought. Probable polyneuropathy was diagnosed through impairment of 2 or 3 nerve functions (strength, sensation, tendon reflexes) in the extremities with symmetrical and distal distribution.

RESULTS: The sample included 347 patients with diabetes (8.3%). Sixty-six of them (19%) had symptoms and signs consistent with probable polyneuropathy (overall prevalence 1.6%). The disease prevailed in women and in subjects aged 75 years and older. Diabetic patients with polyneuropathy had a longer disease course (P < 0.02) and high mean fasting (P < 0.001) and post-prandial (P < 0.02) blood glucose.

CONCLUSION: Diabetic polyneuropathy in the elderly is a fairly common clinical condition prevailing in women and in subjects 75 years and older. Risk factors for polyneuropathy include prolonged disease duration and high mean fasting and post-prandial blood glucose.