Clinical correlation and disease phenotype in patients with esophageal achalasia and comorbid autoimmune diseases.

Background: There is evidence that idiopathic achalasia has an autoimmune component and a significant association with several autoimmune comorbidities has been described. However, data regarding the prevalence of autoimmune diseases in achalasia are not well established, and few studies have explored this association.

Objective: Our primary aim was to prospectively investigate the type and frequency of autoimmune comorbidities in a large cohort of consecutive achalasia patients. Our secondary aim was to investigate the effects of autoimmune comorbidities on achalasia phenotype (clinical features and manometric pattern).

Methods: The study population consisted of 375 consecutive patients (215 females-median age 55 ± 17 years), referred at our tertiary referral center from January 2008 to January 2018, with clinical and instrumental (EGDS, barium esophagogram, and manometry) diagnosis of idiopathic achalasia. Gender- and age-matched subjects undergoing manometry and pH-impedance monitoring for typical gastroesophageal reflux (GERD) complaints served as controls. In all patients a detailed history taking was carried out, recording the presence and type of autoimmune comorbidities.

Results: The overall prevalence of autoimmune comorbidities was two times higher in achalasia than in control patients (12.3 vs. 5%, respectively). The presence of comorbidities did not significantly affect disease's phenotype, as the age of disease onset was similar in achalasia patients with and without comorbidities (50.13 ± 14.47 and 48.3 ± 18.71, respectively, P = NS).

Conclusions: Although larger epidemiologic studies are needed to confirm our data, our findings likely suggest that achalasia has a complex multifactorial pathophysiology with an autoimmune component.