The Epidemiology of Diabetic Neuropathy

Diabetic neuropathy is one of the most common complications to diabetes that is associated with substantial negative individual and socioeconomic consequences. Diabetic neuropathy encompasses a heterogeneous group of neuropathic syndromes with varying clinical manifestations. The most common forms of diabetic neuropathy are: distal symmetric polyneuropathy (DSPN) and cardiovascular autonomic neuropathy (CAN). Estimating prevalence and incidence rate is challenging as diagnostic criteria for the complications vary between studies and depending on the geographical origin of studies. In addition, scares data is available from longitudinal studies, which restricts the ability to present substantial data on incidence rates and disease progression. Based on reviews of major studies of diabetic neuropathy from the last four decades, we present data on the global prevalence and incidence of DSPN and CAN. In summary, the prevalence of clinical DSPN varies between 20% and 30% for both type 1 and type 2 diabetes, with significant variability between studies and geographical regions. Approximately, 15% of people with diabetes suffer from painful DSPN. A common risk maker for DSPN and painful DSPN is diabetes duration. The incidence of DSPN is generally higher in type 2 diabetes than in type 1 diabetes. CAN prevalence in type 1 diabetes and type 2 diabetes also varies by geographical region. Estimates vary between 10 and 30% with a tendency to higher prevalence in non-Western regions. CAN prevalence increases with age. No apparent changes in prevalence have been observed from the 1990s to the present. In summary, diabetic neuropathies are common and variations in prevalence are related to geographical region. Prevalence estimates are possibly subjected to inaccuracies due to varying diagnostic modalities and criteria.