Incidence of Appendicitis over Time: A Comparative Analysis of an Administrative Healthcare Database and a Pathology-Proven Appendicitis Registry

<div><p>Importance</p><p>At the turn of the 21^st century, studies evaluating the change in incidence of appendicitis over time have reported inconsistent findings.</p><p>Objectives</p><p>We compared the differences in the incidence of appendicitis derived from a pathology registry versus an administrative database in order to validate coding in administrative databases and establish temporal trends in the incidence of appendicitis.</p><p>Design</p><p>We conducted a population-based comparative cohort study to identify all individuals with appendicitis from 2000 to2008.</p><p>Setting & Participants</p><p>Two population-based data sources were used to identify cases of appendicitis: 1) a pathology registry (n = 8,822); and 2) a hospital discharge abstract database (n = 10,453).</p><p>Intervention & Main Outcome</p><p>The administrative database was compared to the pathology registry for the following <i>a priori</i> analyses: 1) to calculate the positive predictive value (PPV) of administrative codes; 2) to compare the annual incidence of appendicitis; and 3) to assess differences in temporal trends. Temporal trends were assessed using a generalized linear model that assumed a Poisson distribution and reported as an annual percent change (APC) with 95% confidence intervals (CI). Analyses were stratified by perforated and non-perforated appendicitis.</p><p>Results</p><p>The administrative database (PPV = 83.0%) overestimated the incidence of appendicitis (100.3 per 100,000) when compared to the pathology registry (84.2 per 100,000). Codes for perforated appendicitis were not reliable (PPV = 52.4%) leading to overestimation in the incidence of perforated appendicitis in the administrative database (34.8 per 100,000) as compared to the pathology registry (19.4 per 100,000). The incidence of appendicitis significantly increased over time in both the administrative database (APC = 2.1%; 95% CI: 1.3, 2.8) and pathology registry (APC = 4.1; 95% CI: 3.1, 5.0).</p><p>Conclusion & Relevance</p><p>The administrative database overestimated the incidence of appendicitis, particularly among perforated appendicitis. Therefore, studies utilizing administrative data to analyze perforated appendicitis should be interpreted cautiously.</p></div

Incidence of Appendicitis over Time: A Comparative Analysis of an Administrative Healthcare Database and a Pathology-Proven Appendicitis Registry - Fig 2

<p>Annual incidence of appendicitis stratified by perforated and non-perforated from cohorts derived by A) a pathology proven registry; and B) an administrative healthcare database.</p

Clinical characteristics of patients with appendicitis derived from a pathology-proven registry and from an administrative healthcare database.

<p>Clinical characteristics of patients with appendicitis derived from a pathology-proven registry and from an administrative healthcare database.</p

Comparative analysis in incidence and temporal trends between cohorts of appendicitis patients derived from a pathology-proven registry and an administrative healthcare database.

<p>Comparative analysis in incidence and temporal trends between cohorts of appendicitis patients derived from a pathology-proven registry and an administrative healthcare database.</p

Flow-chart of the study populations derived for the pathology proven registry and the administrative healthcare database.

<p>Flow-chart of the study populations derived for the pathology proven registry and the administrative healthcare database.</p

Positive predictive value of coding in the administrative healthcare database as compared to the pathology-proven registry stratified overtime.

<p>Positive predictive value of coding in the administrative healthcare database as compared to the pathology-proven registry stratified overtime.</p

Unadjusted and adjusted odds ratios with 95% confidence intervals (CI) of requiring surgical management of diverticulitis.

<p>Unadjusted and adjusted odds ratios with 95% confidence intervals (CI) of requiring surgical management of diverticulitis.</p

Baseline characteristics of patients stratified by surgery and no surgery.

<p>Baseline characteristics of patients stratified by surgery and no surgery.</p

Systematic review of observational studies that have studied the relationship between smoking and diverticulitis.

<p>Systematic review of observational studies that have studied the relationship between smoking and diverticulitis.</p

Past and future burden of inflammatory bowel diseases based on modeling of population-based data

BACKGROUND & AIMS: Inflammatory bowel diseases (IBDs) exist worldwide, with high prevalence in North America. IBD is complex and costly, and its increasing prevalence places a greater stress on health care systems. We aimed to determine the past current, and future prevalences of IBD in Canada. METHODS: We performed a retrospective cohort study using population-based health administrative data from Alberta (2002–2015), British Columbia (1997– 2014), Manitoba (1990–2013), Nova Scotia (1996–2009), Ontario (1999–2014), Quebec (2001–2008), and Saskatchewan (1998–2016). Autoregressive integrated moving average regression was applied, and prevalence, with 95% prediction intervals (PIs), was forecasted to 2030. Average annual percentage change, with 95% confidence intervals, was assessed with log binomial regression. RESULTS: In 2018, the prevalence of IBD in Canada was estimated at 725 per 100,000 (95% PI 716–735) and annual average percent change was estimated at 2.86% (95% confidence interval 2.80%–2.92%). The prevalence in 2030 was forecasted to be 981 per 100,000 (95% PI 963–999): 159 per 100,000 (95% PI 133–185) in children, 1118 per 100,000 (95% PI 1069–1168) in adults, and 1370 per 100,000 (95% PI 1312–1429) in the elderly. In 2018, 267,983 Canadians (95% PI 264,579–271,387) were estimated to be living with IBD, which was forecasted to increase to 402,853 (95% PI 395,466–410,240) by 2030. CONCLUSION: Forecasting prevalence will allow health policy makers to develop policy that is necessary to address the challenges faced by health systems in providing high-quality and cost-effective care