Incidence of appendicitis according to region of origin in first- and second-generation immigrants and adoptees in Sweden. A cohort follow-up study

The Global Burden of Appendicitis in 204 Countries and Territories from 1990 to 2019

OBJECTIVE

Appendicitis is a common surgical emergency. This study aimed to estimate the worldwide burden and trends of appendicitis from 1990 to 2019.

METHODS

Data on appendicitis were derived from the Global Burden of Disease 2019. Incidence and disability-adjusted life-years (DALYs) data were analyzed at global, regional, and national levels and stratified by sex, age, and socio-demographic index. The estimated annual percentage change and relative change were used to assess changing trends. Pearson's correlation test was used to assess the correlation between different measures.

RESULTS

Global incidence grew by 63.55% between 1990 and 2019, age-standardized incidence rate climbed by an estimated percentage change of 0.58 per year, whereas the number of DALY declined by 31.93% during the same period, with an estimated annual percentage change of -2.77. In 2019, the areas of Andean Latin America and the Caribbean had the highest age-standardized rates of incidence and DALYs. While South Asia saw the largest increase in age-standardized incidence rates, Andean Latin America saw the biggest decline in age-standardized rates of incidence and DALYs. At the national level, Bangladesh, Bhutan, and Peru were the top three countries in terms of age-standardized incidence rates in 2019, and Honduras, Haiti, and the Central African Republic held the highest age-standardized DALY rates. Ethiopia experienced the most age-standardized incidence rate increase, and Peru saw the largest decline in age-standardized rate of incidence and DALYs. Significant negative correlations between age-standardized DALY rates and socio-demographic index, between estimated annual percentage change and age-standardized incidence rates, were observed at the national level.

CONCLUSION

Appendicitis remains a major global health concern. Although the trends in DALYs decreased, the burden of incidence increased from 1990 to 2019. Policymakers should create health policies adapted to local conditions to manage the burden of appendicitis globally.

Demographic factors associated with length of stay in hospital and histological diagnosis in adults undergoing appendicectomy

Objective: Appendicectomy remains of the most common emergency operations in the United Kingdom. The exact etiologies of appendicitis remain unclear with only potential causes suggested in the literature. Social deprivation and ethnicity have both been demonstrated to influence outcomes following many operations. There are currently no studies evaluating their roles with regards to severity and outcomes following appendicectomy.

Material and Methods: Demographic data were retrieved from health records for adult patients who underwent appendicectomy between 2010-2016 within a single NHS trust. To measure social deprivation, Indices of Multiple Deprivation (IMD) rankings were used. Histology reports were reviewed and diagnosis classified into predefined categories: non-inflamed appendix, uncomplicated appendicitis, complicated appendicitis and gangrenous appendicitis.

Results: Three thousand four hundred and forty-four patients were identified. Mean age was 37.8 years (range 73 years). Using a generalized linear model, South Asian ethnicity specifically was found to be independently predictive of increased length of stay following appendicectomy (p< 0.001). Amongst South Asian patients, social deprivation was found to be further predictive of longer hospital stay (p= 0.005). Deprivation was found to be a predictor of complicated appendicitis but not of gangrenous appendicitis (p= 0.01). Male gender and age were also independent predictors of positive histology for appendicitis (p< 0.001 and p= 0.021 respectively).

Conclusion: This study is the first to report an independent association between South Asian ethnicity and increased length of stay for patients undergoing appendicectomy in a single NHS trust. The associations reported in this study may be a result of differences in the pathophysiology of acute appendicitis or represent inequalities in healthcare provision across ethnic and socioeconomic groups.

Nationwide paediatric cohort study of a protective association between allergy and complicated appendicitis

BACKGROUND

In a nationwide cohort the potentially protective association between allergy and complicated appendicitis was analysed, and the influence of seasonal antigens, antihistamine treatment, and timing of allergy onset assessed.

METHODS

Some 1 112 571 children born between 2000 and 2010 were followed from birth until the end of 2014. A cross-sectional analysis of appendicitis cases, with comparison of allergic versus non-allergic children for absolute risk and odds of complicated appendicitis was first undertaken. This was followed by a longitudinal analysis of children with allergy and matched controls who had never had an allergy, for incidence rate and hazard of subsequent complicated or simple appendicitis.

RESULTS

Of all children, 20.4 per cent developed allergy and 0.6 per cent had appendicitis during follow-up. Among children with appendicitis, complicated appendicitis was more common among non-allergic children (18.9 per cent, 948 of 5016) than allergic children (12.8 per cent, 173 of 1351) (P < 0.001), and allergic children had a lower adjusted odds of complicated appendicitis (adjusted odds ratio (OR) 0.80, 95 per cent c.i. 0.67 to 0.96; P = 0.021). The risk of complicated appendicitis among children with manifest allergy was reduced by one-third in the longitudinal analysis (incidence rate 0.13 versus 0.20 per 1000 person-years; hazard ratio (HR) 0.68, 95 per cent c.i. 0.58 to 0.81; P < 0.001), whereas the risk of simple appendicitis remained unchanged (incidence rate 0.91 versus 0.91; HR 1.00, 0.94 to 1.07; P = 0.932). Seasonal antigen exposure was a protective factor (adjusted OR 0.82, 0.71 to 0.94; P = 0.004) and ongoing antihistamine medication a risk factor (adjusted OR 2.28, 1.21 to 4.28; P = 0.012).

CONCLUSION

Children with allergy have a lower risk of complicated appendicitis, but the same overall risk of simple appendicitis. Seasonal antigen exposure reduced, and antihistamine treatment increased, the risk of complicated disease.

Deprivation increases perforation risk in paediatric appendicitis

Acute appendicitis is the most common surgical emergency in childhood. Perforation of the appendix conveys a worse outcome.This case-control study investigated the relationship between deprivation and appendiceal perforation in children in the West of Scotland.All children undergoing acute appendicectomy over a 2-year period were identified. Basic demographics including Scottish Index of Multiple Deprivation (SIMD) rank and clinical features including time to presentation and surgical findings were recorded. Associations were investigated using multivariable analysis.304 patients (62% male) underwent appendicectomy. Mean age was 10.4 years (SD ±3.5). Mean time from symptom onset to presentation was 2.3 days (SD ±2.5). Perforation rate was 44.41%.Perforation was associated with lower age (p=0.004, OR -0.10, 95% CI -0.17 to -0.33), increased time to presentation (p=0.044, OR 0.14, 95% CI 0.004 to 0.27) and SIMD tertile (p=0.027, OR 0.63, 95% CI 0.07 to 1.20). SIMD tertile was not associated with delayed presentation.Worsening deprivation independently predicts perforation, but this relationship is not mediated through a delay in presentation.

Antibiotics during childhood and development of appendicitis-a nationwide cohort study

BACKGROUND

Appendicitis is a common disease with a lifespan risk of approximately 8%. The full range of specific causes for the disease remains elusive, but an aberrant microbiota have been identified as a potential risk factor.

AIM

To investigate if use of antibiotics in a paediatric population increases the risk of appendicitis in childhood and adolescence METHODS: We conducted a cohort study from 1 January 1995 to 31 December 2014. A total of 1 385 707 children (0-19 years of age) including 7 406 397 antibiotic prescriptions and 11 861 cases of appendicitis were included. Primary outcome was appendicitis requiring appendectomy according to previous use of antibiotics. Appendicitis and appendectomy were identified from nationwide hospital records, and exposure to antibiotics was identified from nationwide prescription register. Rate ratios (RRs) with 95% confidence intervals were estimated from Poisson and logistic regression models.

RESULTS

Children who received at least one course of antibiotics were at increased risk of developing appendicitis compared to unexposed children (adjusted RR 1.72 [95% confidence interval 1.61-1.85]), mean age of developing appendicitis was 9.8 years (SD 4.1 years). The RR of appendicitis increased by 1.04 (1.04-1.04) per antibiotic course. A higher risk of appendicitis was observed in children exposed to antibiotics within the first 6 months of life (RR 1.46 [1.36-1.56]) and children exposed to broad-spectrum antibiotics (RR 1.33 [1.27-1.39]). After adjustment for number of antibiotic courses, the association between early age of antibiotic exposure and risk of appendicitis and the association between exposure to broad-spectrum antibiotics and the risk of appendicitis both disappeared.

CONCLUSION

Children who receive antibiotics are at increased and dose-dependent risk of appendicitis. The underlying mechanisms merit further investigation.

Genetic polymorphism patterns suggest a genetic driven inflammatory response as pathogenesis in appendicitis

PURPOSE

The pathogenesis of appendicitis is not well understood. Environmental factors are regarded most important, but epidemiologic findings suggest a role of inflammatory and genetic mechanisms. This study determines the association of single nucleotide polymorphisms (SNPs) of inflammatory genes with appendicitis.

METHODS

As part of a larger prospective study on the diagnostic value of inflammatory variables in appendicitis, the genotype frequency of 28 polymorphisms in 26 inflammatory response genes from the appendicitis and control patients was analyzed in blood samples from 343 patients, 100 with appendicitis, and 243 with non-specific abdominal pain, using TaqMan SNP genotyping assays.

RESULTS

Associations with appendicitis were found for SNPs IL-13 rs1800925 with odds ratio (OR) 6.02 (95% CI 1.52-23.78) for T/T versus C/C + T/T, for IL-17 rs2275913 with OR 2.38 (CI 1.24-4.57) for A/A vs G/G + GA, for CCL22 rs223888 with OR 0.12 (0.02-0.90), and for A/A vs G/G + GA. Signs of effect modification of age for the association with appendicitis were found for IL-13 rs1800925 and CTLA4 rs3087243. Stratified analysis showed difference in association with severity of disease for IL-17 rs2275913 and CD44 rs187115.

CONCLUSIONS

The association of gene variants on risk of appendicitis and its severity suggest an etiologic role of genetically regulated inflammatory response. This may have implications for understanding the prognosis of untreated appendicitis as a possible self-limiting disorder and for understanding the inverse association of appendicitis with ulcerative colitis.

Nationwide study of appendicitis in children

Background

Paediatric surgical care is increasingly being centralized away from low‐volume centres, and prehospital delay is considered a risk factor for more complicated appendicitis. The aim of this study was to determine the incidence of paediatric appendicitis in Sweden, and to assess whether distance to the hospital was a risk factor for complicated disease.

Methods

A nationwide cohort study of all paediatric appendicitis cases in Sweden, 2001–2014, was undertaken, including incidence of disease in different population strata, with trends over time. The risk of complicated disease was determined by regression methods, with travel time as the primary exposure and individual‐level socioeconomic determinants as independent variables.

Results

Some 38 939 children with appendicitis were identified. Of these, 16·8 per cent had complicated disease, and the estimated risk of paediatric appendicitis by age 18 years was 2·5 per cent. Travel time to the treating hospital was not associated with complicated disease (adjusted odds ratio (OR) 1·00 (95 per cent c.i. 0·96 to 1·05) per 30‐min increase; P = 0·934). Level of education (P = 0·177) and family income (P = 0·120) were not independently associated with increased risk of complicated disease. Parental unemployment (adjusted OR 1·17, 95 per cent c.i. 1·05 to 1·32; P = 0·006) and having parents born outside Sweden (1 parent born in Sweden: adjusted OR 1·12, 1·01 to 1·25; both parents born outside Sweden: adjusted OR 1·32, 1·18 to 1·47; P < 0·001) were associated with an increased risk of complicated appendicitis.

Conclusion

Every sixth child diagnosed with appendicitis in Sweden has a more complicated course of disease. Geographical distance to the surgical facility was not a risk factor for complicated appendicitis.