Incidence, Morbidity, and Mortality of Achalasia: A Nationwide, Population-Based Cohort Study in South Korea

Abstract

Background/Aims: Although an association between achalasia and esophageal cancer has been reported, whether achalasia confers a substantial increase in mortality is unknown. Moreover, the causes of death related to achalasia have not been investigated. We performed this nationwide, population-based cohort study on achalasia because no such study has been performed since the introduction of high-resolution manometry in 2008. Methods:This study was performed using data extracted from the Korean National Health Insurance Service database, covering a 9-year period from 2009 to 2017. Control participants without a diagnostic code for achalasia were randomly selected and matched by sex and birth year at a case-to-control ratio of 1:4. Data on the cause of death from Statistics Korea were also analyzed. Results:The overall incidence of achalasia was 0.68 per 100,000 person-years, and the prevalence was 6.46 per 100,000 population. Patients with achalasia (n=3,063) had significantly higher adjusted hazard ratio (aHR) for esophageal cancer (aHR, 3.40; 95% confidence interval [CI], 1.25 to 9.22; p=0.017), pneumonia (aHR, 2.30; 95% CI, 1.89 to 2.81; p<0.001), aspiration pneumonia (aHR, 3.92; 95% CI, 2.38 to 6.48; p<0.001), and mortality (aHR, 1.68; 95% CI, 1.44 to 1.94; p<0.001). Esophageal cancer carried the highest mortality risk (aHR, 8.82; 95% CI, 2.35 to 33.16; p=0.001), while pneumonia had the highest non-cancer mortality risk (aHR, 2.28; 95% CI, 1.31 to 3.96; p=0.004). Conclusions:In this nationwide study, achalasia was associated with increased risk of mortality. Esophageal cancer and pneumonia were the most common comorbidities and the major causes of death in patients with achalasia.

Global trends in incidence and prevalence of achalasia, 1925–2021: A systematic review and meta‐analysis

“…Initially, the search strategy identified 2306 studies. Of these, 26 studies met the eligibility criteria, 2,9–33 involving 269,315,171 participants and 20,873 patients with achalasia from 14 countries across five continents. Figure 1 shows a global incidence and prevalence map, and figure summarizes the results of the search strategy.…”

“…A total of 26 studies had incidence data, 2,9–33 and the global pooled incidence of achalasia was 0.78 cases per 100,000 person‐years (95% CI, 0.64–0.93; I 2 = 99.230%), with a 95% prediction interval of −0.03–1.60 (Table 2).…”

“…Risk of bias was evaluated for 27 studies, and one study was excluded from the analysis due to high RoB 34 . Seven studies were found to have a moderate RoB 9,11,14,15,20,25,33 and the remaining 19 studies were evaluated to have a low RoB 2,10,12,13,16–19,21–24,26–32 . The details of the RoB in the studies included in the analysis are listed in Table .…”

“…In our systematic review, 14 studies 2,12,14,18,19,21,24,26,[28][29][30][31][32][33] with prevalence data were used to estimate the global pooled prevalence of achalasia (Table 3). It was estimated to be 10.82 cases per 100,000 person-years (95% CI, 8.15-13.48; I 2 = 99.619%) with a 95% prediction interval of −0.56-22.20.…”

“…Achalasia is a rare motility disorder of the esophagus characterized by impaired relaxation of the lower esophageal sphincter 1 . Not only does this condition impose high economic burdens, but it also poses a significant risk factor for esophageal cancer 1,2 …”