Earlier development of diabetic neuropathy in men than in women with type 2 diabetes mellitus

Abstract

Data about the prevalence of diabetic neuropathy (DN) differ substantially, depending on the population and diagnostic methods. Sex-specific differences in DN are rarely discussed. The aims of the present study were to assess the prevalence of, and analyze sex differences in, DN in a hospital population with type 2 diabetes mellitus (T2DM) over a period of 18 years. In this retrospective study performed at a university hospital endocrinology clinic in Sofia, patient clinical records from 1990-2007 were examined. Patients were included in the database only at their first admission. Data from 1705 patients with T2DM were analyzed (961 women, 744 men; mean [SD] age, 60.0 [11.9] years; diabetes duration, 9.9 [8.4] years; glycosylated hemoglobin, 9.0% [2.2%]; and body mass index, 29.4 [6.0] kg/m²). Obesity (46.3% vs 32.0%; P < 0.001), hypertension (86.7% vs 77.8%; P < 0.001), and dyslipidemia (61.2% vs 55.0%; P < 0.05) were significantly more common in women than in men, respectively. The prevalence of DN was 78.8%, with no significant sex differences. However, prevalence differed with time, corresponding to the frequency of application of electrophysiologic (electromyograms) or semiquantitative instrumental diagnostic methods. In men, the median (25th-75th percentiles) interval between diagnosis of T2DM and diagnosis of DN was 6 (1-12) years; in women, the interval was 8 (4-13) years (P < 0.01). In this study of Bulgarian patients with T2DM, women were at higher macrovascular risk than were men. A high prevalence of DN was observed among these patients. The period from the diagnosis of T2DM to DN was shorter in men than in women-this necessitates earlier screening and therapeutic intervention for DN in men. Reasons for this sex difference may include differences in lifestyle and the testosterone deficiency that is common in men with diabetes, leading to a more pronounced deficit of neurosteroids.