Incidence and mortality of alcohol-related dementia and Wernicke-Korsakoff syndrome: A nationwide register study.

Background: Epidemiological data on alcohol-related cognitive disorders are scarce. Up-to-date population-based incidence and mortality rates for Wernicke-Korsakoff syndrome (WKS) and alcohol-related dementia (ARD) are necessary to understand the burden of these diseases.

Methods: We collected diagnostic data from the Finnish Hospital Discharge Register and mortality data from Statistics Finland for all persons aged ≥40 years who had received a diagnosis of WKS (n = 1149) or ARD (n = 2432) between 1998 and 2015 in Finland. We calculated the incidences and mortality in relation to the age-, sex- and calendar year-matched general population. Causes of death were ascertained from death certificates.

Results: For WKS, the incidence per 100,000 person-years (95% confidence interval (CI)) was 3.7 (3.4-3.9) in men and 1.2 (1.1-1.3) in women. For ARD, the incidence was 8.2 (7.9-8.6) in men and 2.1 (1.9-2.3) in women. The incidence of WKS peaked in people aged 50-59 years and the incidence of ARD in people aged 70-79 years. The standardized mortality ratio (95% CI) was 5.67 (5.25-6.13) in WKS patients and 5.41 (5.14-5.70) in ARD patients. Most of the excess mortality resulted from alcohol-related causes.

Conclusions: To our knowledge, this is the first study describing population-based incidence and mortality rates, sex-segregated data and causes of death in patients with WKS or ARD. Our results establish a point of reference for the incidence of WKS and ARD and show the high mortality and poor prognosis of these disorders.