The prevalence of Wernicke's encephalopathy, according to unselected autopsy studies, varies throughout the world from 0.8% to 2.8%.[14]Harper C, Fornes P, Duyckaerts C, et al. An international perspective on the prevalence of the Wernicke-Korsakoff syndrome. Metab Brain Dis. 1995 Mar;10(1):17-24.
http://www.ncbi.nlm.nih.gov/pubmed/7596325?tool=bestpractice.com
[15]Torvik A. Wernicke's encephalopathy: prevalence and clinical spectrum. Alcohol Alcohol Suppl. 1991;1:381-4.
http://www.ncbi.nlm.nih.gov/pubmed/1845567?tool=bestpractice.com
According to clinical studies, this figure is lower, between 0.04% and 0.13%, perhaps reflecting underdiagnosis of this condition.[16]Harper CG, Giles M, Finlay-Jones R. Clinical signs in the Wernicke-Korsakoff complex: a retrospective analysis of 131 cases diagnosed at necropsy. J Neurol Neurosurg Psychiatry. 1986 Apr;49(4):341-5.
http://www.ncbi.nlm.nih.gov/pubmed/3701343?tool=bestpractice.com
[17]Victor M, Adams RD, Collins GH. The Wernicke-Korsakoff syndrome: a clinical and pathological study of 245 patients, 82 with post-mortem examinations. Contemp Neurol Ser. 1971;7:1-206.
http://www.ncbi.nlm.nih.gov/pubmed/5162155?tool=bestpractice.com
Wernicke’s encephalopathy has a higher prevalence in patients with a history of alcohol dependence (12.5%), AIDS (10%), and bone marrow transplantation (6%).[18]Torvik A, Lindboe CF, Rogde S. Brain lesions in alcoholics: a neuropathological study with clinical correlations. J Neurol Sci.1982 Nov;56(2-3):233-48.
http://www.ncbi.nlm.nih.gov/pubmed/7175549?tool=bestpractice.com
[19]Boldorini R, Vago L, Lechi A, et al. Wernicke's encephalopathy: occurrence and pathological aspects in a series of 400 AIDS patients. Acta Biomed Ateneo Parmense. 1992;63(1-2):43-9.
http://www.ncbi.nlm.nih.gov/pubmed/1340667?tool=bestpractice.com
[20]Bleggi-Torres LF, de Medeiros BC, Werner B, et al. Neuropathological findings after bone marrow transplantation: an autopsy study of 180 cases. Bone Marrow Transplant. 2000 Feb;25(3):301-7.
http://www.ncbi.nlm.nih.gov/pubmed/10673702?tool=bestpractice.com
[21]Choi YJ, Park SJ, Kim JS, et al. Wernicke's encephalopathy following allogeneic hematopoietic stem cell transplantation. Korean J Hematol. 2010 Dec;45(4):279-81.
https://synapse.koreamed.org/articles/1032915
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Other risk factors include malnutrition of any cause, malignancy, gastrointestinal surgery (particularly bariatric surgery), and hyperemesis gravidarum.[22]Nagarajan E, Rupareliya C, Bollu PC. Wernicke's encephalopathy as a rare complication of hyperemesis gravidarum: a case report and Review of literature. Cureus. 2018 May 9;10(5):e2597.
http://www.ncbi.nlm.nih.gov/pubmed/30013861?tool=bestpractice.com
[23]Sechi G, Serra A. Wernicke's encephalopathy: new clinical settings and recent advances in diagnosis and management. Lancet Neurol. 2007 May;6(5):442-55.
http://www.ncbi.nlm.nih.gov/pubmed/17434099?tool=bestpractice.com
The prevalence is higher in males (male:female ratio of 1.7:1).[17]Victor M, Adams RD, Collins GH. The Wernicke-Korsakoff syndrome: a clinical and pathological study of 245 patients, 82 with post-mortem examinations. Contemp Neurol Ser. 1971;7:1-206.
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One nationwide register study investigating the incidence and mortality of Wernicke's encephalopathy reported an incidence per 100,000 person-years of 3.7 in men (95% CI 3.4 to 3.9) and 1.2 in women (95% CI 1.1 to 1.3).[24]Palm A, Vataja R, Talaslahti T, et al. Incidence and mortality of alcohol-related dementia and Wernicke-Korsakoff syndrome: A nationwide register study. Int J Geriatr Psychiatry. 2022 Aug;37(8):10.1002/gps.5775.
https://onlinelibrary.wiley.com/doi/10.1002/gps.5775
http://www.ncbi.nlm.nih.gov/pubmed/35789035?tool=bestpractice.com
This finding is attributed to the increased frequency of alcohol-use disorders in men; however, non-alcohol-related Wernicke's encephalopathy may be more common in women.[25]Scalzo SJ, Bowden SC, Ambrose ML, et al. Wernicke-Korsakoff syndrome not related to alcohol use: a systematic review. J Neurol Neurosurg Psychiatry. 2015 Dec;86(12):1362-8.
http://www.ncbi.nlm.nih.gov/pubmed/25589780?tool=bestpractice.com