Prevalence and Risk Factor Profiles for Chronic Axonal Polyneuropathy in the General Population

Background And Objectives: Chronic axonal polyneuropathy is a common disease with increasing prevalence with age. It majorly affects quality of life and leads to difficulties with various activities. Persons with polyneuropathy often not seek medical care and thus the societal burden of disease is likely underreported. Given the aging populations, contemporary data on the prevalence and risk factor profiles of polyneuropathy in the general population are required. Therefore, we estimated the current and expected prevalence and investigated the (co-)occurrence of risk factors in participants with chronic axonal polyneuropathy.

Methods: Between June 2013 and January 2020, participants of the population-based Rotterdam Study underwent extensive in-person examination to diagnose polyneuropathy. Age-standardized prevalence's were calculated for populations age 40 years or older of the Netherlands, Europe, the United States, and the world population. Putative risk factors were identified using laboratory findings, interviews, questionnaire data, and a review of medical records.

Results: In total, 4,114 participants were included (mean age 64.3 years, 55.2% females), of whom 167 had chronic axonal polyneuropathy. More than half (54.5%) had yet not received the diagnosis through regular care. Age-standardized prevalence's were 3.3% (95% CI 2.8-4.0) for the European, 3.0% (95% CI 2.5-3.5) for the United States, and 2.3% (95% CI 1.9-2.8) for the world population. Based on the expected age distributions, the prevalence of chronic axonal polyneuropathy will increase with ±25% in the next 20 years. Known risk factors were present in 62.9% (N = 105) of the cases with polyneuropathy and most often included diabetes (34.1%) and vitamin deficiencies (15.1%). Importantly, combinations of various risk factors were found in 20.4% (N = 34) of cases with polyneuropathy.

Discussion: Prevalence of chronic axonal polyneuropathy increases with age and is expected to further rise over time. Combinations of multiple known risk factors are often present, indicating the need for a full diagnostic workup, even when a single risk factor for polyneuropathy is known. These findings suggest that cumulative effects of multiple risk factors are important in the development and course of disease.