Stress-Related Disorders Among Young Individuals With Surgical Removal of Tonsils or Adenoids

Importance Studies have suggested an increased risk of psychiatric disorders and suicidal behavior among individuals who have undergone tonsillectomy. However, little is known about stress-related disorders. Objective To investigate whether surgical removal of tonsils or adenoids is associated with a subsequent risk of stress-related disorders. Design, Setting, and Participants This cohort study used Swedish nationwide population and health registry data of all individuals born between January 1, 1981, and December 31, 2016. Individuals who had undergone surgical removal of tonsils or adenoids (ie, exposed persons) were compared with unrelated unexposed individuals individually matched by sex, birth year, and calendar date at the start of follow-up (population-matched cohort) and with their unexposed full siblings (sibling-matched cohort). The analysis was performed between December 15, 2023, and October 11, 2024. Exposure Surgical removal of tonsils or adenoids. Main Outcomes and Measures The Swedish Patient Register was used to identify stress-related disorders, including posttraumatic stress disorder (PTSD), acute stress reaction, and adjustment disorder or other stress reaction. In the population-matched cohort, a Cox proportional hazards regression model was used to assess the association of tonsillectomy with the risk of stress-related disorders, conditioned on sex, birth year, and calendar date at the start of follow-up and adjusted for parental educational attainment and history of stress-related disorders. To address potential familial confounding, analyses were replicated using the sibling-matched cohort. Results The population-matched cohort included 83 957 exposed and 839 570 unexposed persons (median [IQR] age at the start of follow-up, 14.4 [6.5-18.6] years; 55.2% female), and the sibling-matched cohort included 51 601 exposed persons (median [IQR] age at start of follow-up, 14.9 [6.9-18.7] years, 55.8% female) and 75 159 unexposed full siblings (median [IQR] age at start of follow-up, 13.3 [6.9-19.5] years; 52.6% male). Compared with the unexposed population reference, exposed persons exhibited a higher subsequent risk of stress-related disorders (hazard ratio [HR], 1.43; 95% CI, 1.38-1.48), especially PTSD (HR, 1.55; 95% CI, 1.43-1.69). These results were replicated in the sibling-matched cohort (any stress-related disorder: HR, 1.34 [95% CI, 1.25-1.44]; PTSD: HR, 1.41 [95% CI, 1.18-1.69]). An increased risk was consistently noted regardless of sex, age at surgery, time since surgery, parental educational attainment, or parental history of stress-related disorders and was mainly noted for a surgery due to adenotonsillar diseases or sleep and respiratory abnormalities. Conclusions and Relevance In this cohort study, the findings suggest that early-life surgical removal of tonsils or adenoids is associated with a higher future risk of stress-related disorders and highlight a need to understand the role of adenotonsillar diseases or associated health conditions in the development of stress-related psychiatric disorders.