World Journal of Surgery

, Volume 36, Issue 12, pp 2787–2794 | Cite as

Examining a Common Disease with Unknown Etiology: Trends in Epidemiology and Surgical Management of Appendicitis in California, 1995–2009

  • Jamie E. AndersonEmail author
  • Stephen W. Bickler
  • David C. Chang
  • Mark A. Talamini



The study was designed to examine the epidemiology of appendicitis and risk factors of perforation and appendectomy.


Retrospective analysis of the California Office of Statewide Health Planning and Development Patient Discharge Data was performed from 1995 to 2009. Patients with appendicitis were identified by ICD-9 diagnosis code. Population statistics from the RAND Corporation were used to calculate incidence rates. Risk factors of perforation and appendectomy were also calculated.


A total of 608,116 patients with appendicitis (70 % non-perforated) were included. The incidence increased at an average rate of 0.5 cases/100,000 population/year (p < 0.001), with annual incidence peaking during the third quarter. Children age 10–14 had the highest rates of appendicitis (169.6 cases/100,000). The lifetime cumulative incidence rate is 9.0 %. Appendicitis is most common in whites and Hispanics and less common in African Americans and Asians. Risks of perforation include Hispanic or Asian race, young or old age, and non-private insurance. The adjusted odds of appendectomy increased since 1995 in patients with non-perforated appendicitis (OR 1.5, 95 % CI (1.3–1.7); p < 0.001), but it decreased in patients with perforated appendicitis (OR 0.4, 95 % CI (0.4–0.5); p < 0.001).


This is the largest epidemiological study of appendicitis to our knowledge in recent years. Incidence has increased over time and is higher in the summer months. Whites and Hispanics have higher rates of appendicitis, but Hispanics and Asians and patients with non-private insurance, have higher odds of perforation. Surgical management of perforated appendicitis has decreased over time. It is unknown why the incidence has increased, displays seasonality, and varies by race.


Appendicitis Private Insurance Acute Care Hospital Perforated Appendicitis Perforation Rate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Conflict of interest

The authors declare no conflict of interest or financial ties to disclose.


  1. 1.
    Luckmann R, Davis P (1991) The epidemiology of acute appendicitis in California: racial, gender, and seasonal variation. Epidemiology 2:323–330PubMedCrossRefGoogle Scholar
  2. 2.
    Addiss DG, Shaffer N, Fowler BS et al (1990) The epidemiology of appendicitis and appendectomy in the United States. Am J Epidemiol 132:295–910Google Scholar
  3. 3.
    Patient discharge data, public data set (2011) California Office of Statewide Health Planning and Development. Accessed 10 Dec 2011
  4. 4.
    RAND California bridged-race postcensal California population by race/ethnicity and age group (2011) RAND Corporation. Accessed 8 Aug 2011
  5. 5.
    Livingston EH, Woodward WA, Sarosi GA et al (2007) Disconnect between incidence of nonperforated and perforated appendicitis: implications for pathophysiology and management. Ann Surg 245:886–892PubMedCrossRefGoogle Scholar
  6. 6.
    Aarabi S, Sidhwa F, Riehle KJ et al (2011) Pediatric appendicitis in New England: epidemiology and outcomes. J Pediatr Surg 46:1014–1106CrossRefGoogle Scholar
  7. 7.
    Seetahal SA, Bolorunduro OB, Sookdeo TC et al (2011) Negative appendectomy: a 10-year review of a nationally representative sample. Am J Surg 201:433–437PubMedCrossRefGoogle Scholar
  8. 8.
    Oyetunji TA, Ong’uti SK, Bolorunduro OB et al (2012) Pediatric negative appendectomy rate: trend, predictors, and differentials. J Surg Res 173:16–20PubMedCrossRefGoogle Scholar
  9. 9.
    Wolkomir A, Kornak P, Elsakr M et al (1987) Seasonal variation of acute appendicitis: a 56-year study. South Med J 80:958–960PubMedCrossRefGoogle Scholar
  10. 10.
    Brumer M (1970) Appendicitis: seasonal incidence and postoperative wound infection. Br J Surg 57:93–99PubMedCrossRefGoogle Scholar
  11. 11.
    Luckmann R (1989) Incidence and case fatality rates for acute appendicitis in California: a population-based study of the effects of age. Am J Epidemiol 129:905–918PubMedGoogle Scholar
  12. 12.
    Jablonski KA, Guagliardo MF (2005) Pediatric appendicitis rupture rate: a national indicator of disparities in healthcare access. Popul Health Metr 3:4PubMedCrossRefGoogle Scholar
  13. 13.
    Nwomeh BC, Chisolm DJ, Caniano DA et al (2006) Racial and socioeconomic disparity in perforated appendicitis among children: where is the problem? Pediatrics 117:870–875PubMedCrossRefGoogle Scholar
  14. 14.
    Smink DS, Fishman SJ, Kleinman K et al (2005) Effects of race, insurance status, and hospital volume on perforated appendicitis in children. Pediatrics 115:920–925PubMedCrossRefGoogle Scholar
  15. 15.
    Lee SL, Shekherdimian S, Chiu VY (2011) Effect of race and socioeconomic status in the treatment of appendicitis in patients with equal health care access. Arch Surg 146:156–161PubMedCrossRefGoogle Scholar
  16. 16.
    Pieracci FM, Eachempati SR, Barie PS et al (2007) Insurance status, but not race, predicts perforation in adult patients with acute appendicitis. J Am Coll Surg 205:445–452PubMedCrossRefGoogle Scholar
  17. 17.
    Wilms IM, de Hoog DE, de Visser DC et al (2011) Appendectomy versus antibiotic treatment for acute appendicitis. Cochrane Database Syst Rev 11:008359Google Scholar
  18. 18.
    Roach JP, Partrick DA, Bruny JL et al (2007) Complicated appendicitis in children: a clear role for drainage and delayed appendectomy. Am J Surg 194:769–772PubMedCrossRefGoogle Scholar
  19. 19.
    Solomkin JS, Mazuski JE, Bradley JS et al (2010) Diagnosis and management of complicated intra-abdominal infection in adults and children: guidelines by the Surgical Infection Society and the Infectious Diseases Society of America. Surg Infect 11:79–109CrossRefGoogle Scholar
  20. 20.
    Hansson J, Korner U, Khorram-Manesh A et al (2009) Randomized clinical trial of antibiotic therapy versus appendectomy as primary treatment of acute appendicitis in unselected patients. Br J Surg 96:473–481PubMedCrossRefGoogle Scholar
  21. 21.
    Ansaloni L, Catena F, Coccolini F et al (2011) Surgery versus conservative antibiotic treatment in acute appendicitis: a systematic review and meta-analysis of randomized controlled trials. Dig Surg 28:210–221PubMedCrossRefGoogle Scholar
  22. 22.
    Fitzmaurice GJ, McWilliams B, Hurreiz H et al (2011) Antibiotics versus appendectomy in the management of acute appendicitis: a review of the current evidence. Can J Surg 54:307–314PubMedCrossRefGoogle Scholar
  23. 23.
    Mason RJ, Moazzez A, Sohn H et al (2012) Meta-analysis of randomized trials comparing antibiotic therapy with appendectomy for acute uncomplicated (no abscess or phlegmon) appendicitis. Surg Infect 13:74–78CrossRefGoogle Scholar
  24. 24.
    Varadhan KK, Humes DJ, Neal KR et al (2010) Antibiotic therapy versus appendectomy for acute appendicitis: a meta-analysis. World J Surg 34:199–220. doi: 10.1007/s00268-009-0343-5 PubMedCrossRefGoogle Scholar
  25. 25.
    Vons C, Barry C, Maitre S et al (2011) Amoxicillin plus clavulanic acid versus appendectomy for treatment of acute uncomplicated appendicitis: an open-label, non-inferiority, randomised controlled trial. Lancet 377:1573–1579PubMedCrossRefGoogle Scholar

Copyright information

© Société Internationale de Chirurgie 2012

Authors and Affiliations

  • Jamie E. Anderson
    • 1
    Email author
  • Stephen W. Bickler
    • 1
  • David C. Chang
    • 1
  • Mark A. Talamini
    • 1
  1. 1.Department of Surgery, Center for Surgical Systems and Public HealthUniversity of California San DiegoSan DiegoUSA

Personalised recommendations