Acute appendicitis is among the most common causes of lower abdominal pain leading patients to attend the accident and emergency department and the most common diagnosis made in young patients admitted to the hospital with an acute abdomen.[7]Di Saverio S, Podda M, de Simone B, et al. Diagnosis and treatment of acute appendicitis: 2020 update of the WSES Jerusalem guidelines. World J Emerg Surg. 2020 Apr 15;15(1):27.
https://wjes.biomedcentral.com/articles/10.1186/s13017-020-00306-3
http://www.ncbi.nlm.nih.gov/pubmed/32295644?tool=bestpractice.com
Around 50,000 cases of appendicitis were treated in hospitals in England in 2020 to 2021.[10]NHS England. Hospital admitted patient care activity, 2021-22. Sep 2022 [internet publication].
https://digital.nhs.uk/data-and-information/publications/statistical/hospital-admitted-patient-care-activity/2021-22
Most cases occurred in the 20 to 59 year age group.[10]NHS England. Hospital admitted patient care activity, 2021-22. Sep 2022 [internet publication].
https://digital.nhs.uk/data-and-information/publications/statistical/hospital-admitted-patient-care-activity/2021-22
A large majority presented (46,297) as medical emergencies.[10]NHS England. Hospital admitted patient care activity, 2021-22. Sep 2022 [internet publication].
https://digital.nhs.uk/data-and-information/publications/statistical/hospital-admitted-patient-care-activity/2021-22
One systematic review of population-based studies reported the pooled incidence of appendicitis or appendectomy in the US in the 21st century to be 100 per 100,000 person-years; the estimated number of cases in the US in 2015 was 378,614.[11]Ferris M, Quan S, Kaplan BS, et al. The global incidence of appendicitis: a systematic review of population-based studies. Ann Surg. 2017 Aug;266(2):237-41.
http://www.ncbi.nlm.nih.gov/pubmed/28288060?tool=bestpractice.com
In the US, the overall lifetime risk of developing acute appendicitis is 8% for males and 7% for females.[12]Snyder MJ, Guthrie M, Cagle S. Acute appendicitis: efficient diagnosis and management. Am Fam Physician. 2018 Jul 1;98(1):25-33.
https://www.aafp.org/afp/2018/0701/p25.html
http://www.ncbi.nlm.nih.gov/pubmed/30215950?tool=bestpractice.com
Data suggest a rapid increase in incidence in newly industrialised countries.[11]Ferris M, Quan S, Kaplan BS, et al. The global incidence of appendicitis: a systematic review of population-based studies. Ann Surg. 2017 Aug;266(2):237-41.
http://www.ncbi.nlm.nih.gov/pubmed/28288060?tool=bestpractice.com
Acute appendicitis most commonly occurs between the ages of 10 and 30 years, with the highest incidence in children and adolescence.[7]Di Saverio S, Podda M, de Simone B, et al. Diagnosis and treatment of acute appendicitis: 2020 update of the WSES Jerusalem guidelines. World J Emerg Surg. 2020 Apr 15;15(1):27.
https://wjes.biomedcentral.com/articles/10.1186/s13017-020-00306-3
http://www.ncbi.nlm.nih.gov/pubmed/32295644?tool=bestpractice.com
[13]Gorter RR, Eker HH, Gorter-Stam MA, et al. Diagnosis and management of acute appendicitis: EAES consensus development conference 2015. Surg Endosc. 2016 Nov;30(11):4668-90.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5082605
http://www.ncbi.nlm.nih.gov/pubmed/27660247?tool=bestpractice.com
There is a slight male to female predominance (1.4:1).[2]Moris D, Paulson EK, Pappas TN. Diagnosis and management of acute appendicitis in adults: a review. JAMA. 2021 Dec 14;326(22):2299-311.
http://www.ncbi.nlm.nih.gov/pubmed/34905026?tool=bestpractice.com