Temperature-attributable deaths are much more likely as a result of cold rather than heat exposure.[4]Gasparrini A, Guo Y, Hashizume M, et al. Mortality risk attributable to high and low ambient temperature: a multicountry observational study. Lancet. 2015 Jul 25;386(9991):369-75.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(14)62114-0/fulltext
http://www.ncbi.nlm.nih.gov/pubmed/26003380?tool=bestpractice.com
Although traditionally common in regions experiencing severe winters, cases have also been reported in milder climates.[4]Gasparrini A, Guo Y, Hashizume M, et al. Mortality risk attributable to high and low ambient temperature: a multicountry observational study. Lancet. 2015 Jul 25;386(9991):369-75.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(14)62114-0/fulltext
http://www.ncbi.nlm.nih.gov/pubmed/26003380?tool=bestpractice.com
[5]MacDonell JE, Wrenn K. Hypothermia in the summer. South Med J. 1991 Jun;84(6):804-5.
http://www.ncbi.nlm.nih.gov/pubmed/2052983?tool=bestpractice.com
[6]Burke WP. A case report of warm weather accidental hypothermia. J Miss State Med Assoc. 2004 Sep;45(9):263-6.
http://www.ncbi.nlm.nih.gov/pubmed/15473218?tool=bestpractice.com
Between 1995 and 2004, an estimated 15,574 of all emergency department visits in the US were hypothermia- or cold-related in nature.[7]Baumgartner EA, Belson M, Rubin C, et al. Hypothermia and other cold-related morbidity emergency department visits: United States, 1995-2004. Wilderness Environ Med. 2008 Winter;19(4):233-7.
https://journals.sagepub.com/doi/10.1580/07-WEME-OR-104.1
http://www.ncbi.nlm.nih.gov/pubmed/19099327?tool=bestpractice.com
On average, around 700 people die annually from accidental hypothermia in the US.[8]Centers for Disease Control and Prevention (CDC). Hypothermia-related deaths - United States, 2003-2004. MMWR Morb Mortal Wkly Rep. 2005 Feb 25;54(7):173-5.
https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5407a4.htm
http://www.ncbi.nlm.nih.gov/pubmed/15729219?tool=bestpractice.com
From 2003 to 2013, a total of 13,419 deaths were recorded as hypothermia-related and unadjusted annual rates ranged from 0.3 to 0.5 per 100,000 population.[9]Meiman J, Anderson H, Tomasallo C, et al. Hypothermia-related deaths--Wisconsin, 2014, and United States, 2003-2013. MMWR Morb Mortal Wkly Rep. 2015 Feb 20;64(6):141-3.
https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6406a2.htm
http://www.ncbi.nlm.nih.gov/pubmed/25695318?tool=bestpractice.com
From 2018 to 2020, deaths attributed to hypothermia or excessive cold were typically higher in more rural areas in the US. Higher death rates were noted in males regardless of urbanization level.[10]QuickStats: death rates attributed to excessive cold or hypothermia, by urbanization level and sex - National Vital Statistics System, 2018-2020. MMWR Morb Mortal Wkly Rep. 2022 Feb 18;71(7):282.
https://pmc.ncbi.nlm.nih.gov/articles/PMC8853478
http://www.ncbi.nlm.nih.gov/pubmed/35176009?tool=bestpractice.com
Of deaths reported between 2003 and 2013 in the US, rates were highest among people ages 65 years or older (mean death rate for males and females were 1.8 and 1.1 per 100,000 of the population, respectively) and males accounted for 67% of deaths.[9]Meiman J, Anderson H, Tomasallo C, et al. Hypothermia-related deaths--Wisconsin, 2014, and United States, 2003-2013. MMWR Morb Mortal Wkly Rep. 2015 Feb 20;64(6):141-3.
https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6406a2.htm
http://www.ncbi.nlm.nih.gov/pubmed/25695318?tool=bestpractice.com
Approximately 10% of deaths were also reported to have alcohol or drug poisoning as a contributing cause.[9]Meiman J, Anderson H, Tomasallo C, et al. Hypothermia-related deaths--Wisconsin, 2014, and United States, 2003-2013. MMWR Morb Mortal Wkly Rep. 2015 Feb 20;64(6):141-3.
https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6406a2.htm
http://www.ncbi.nlm.nih.gov/pubmed/25695318?tool=bestpractice.com
In the UK, the estimated annual number of hypothermia-related deaths is 300 per year, whereas in Canada, the annual incidence of deaths is 8000.[11]Mallet ML. Pathophysiology of accidental hypothermia. QJM. 2002 Dec;95(12):775-85.
https://academic.oup.com/qjmed/article/95/12/775/1572021
http://www.ncbi.nlm.nih.gov/pubmed/12454320?tool=bestpractice.com
In Japan - a country with a rapidly aging population - one retrospective review of an accidental hypothermia registry found that hypothermia was more likely to occur indoors and in people ages 65 years or older.[12]Morita S, Matsuyama T, Ehara N, et al. Prevalence and outcomes of accidental hypothermia among elderly patients in Japan: data from the J-Point registry. Geriatr Gerontol Int. 2018 Oct;18(10):1427-32.
http://www.ncbi.nlm.nih.gov/pubmed/30094918?tool=bestpractice.com
[13]Matsuyama T, Morita S, Ehara N, et al. Characteristics and outcomes of accidental hypothermia in Japan: the J-Point registry. Emerg Med J. 2018 Nov;35(11):659-66.
http://www.ncbi.nlm.nih.gov/pubmed/29886414?tool=bestpractice.com
Homeless people are at disproportionately higher risk of hypothermia as a result of cold exposure and substance misuse.[14]Romaszko J, Cymes I, Dragańska E, et al. Mortality among the homeless: causes and meteorological relationships. PLoS One. 2017 Dec 21;12(12):e0189938.
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0189938
http://www.ncbi.nlm.nih.gov/pubmed/29267330?tool=bestpractice.com
[15]Lane K, Ito K, Johnson S, et al. Burden and risk factors for cold-related illness and death in New York city. Int J Environ Res Public Health. 2018 Mar 30;15(4):632.
https://www.mdpi.com/1660-4601/15/4/632
http://www.ncbi.nlm.nih.gov/pubmed/29601479?tool=bestpractice.com
[16]Zhang P, Wiens K, Wang R, et al. Cold weather conditions and risk of hypothermia among people experiencing homelessness: implications for prevention strategies. Int J Environ Res Public Health. 2019 Sep 5;16(18):3259.
https://www.mdpi.com/1660-4601/16/18/3259
http://www.ncbi.nlm.nih.gov/pubmed/31491874?tool=bestpractice.com
One retrospective cohort study of the International Hypothermia Registry, which included 201 nonconsecutive cases, found that accidental hypothermia was largely identified in young men as a result of mountain accidents.[17]Walpoth BH, Maeder MB, Courvoisier DS, et al. Hypothermic cardiac arrest - retrospective cohort study from the International Hypothermia Registry. Resuscitation. 2021 Oct;167:58-65.
https://www.resuscitationjournal.com/article/S0300-9572(21)00315-4/fulltext
http://www.ncbi.nlm.nih.gov/pubmed/34416307?tool=bestpractice.com