Study links early-life tonsil removal to long-term risk of stress-related disorders

Study links early-life removal of tonsils or adenoids to higher risk of stress-related disorders, including PTSD, in later years

Study: Stress-Related Disorders Among Young Individuals With Surgical Removal of Tonsils or Adenoids. Image Credit: Prostock-studio / Shutterstock.com

A new study published in JAMA Network Open explores the potential association between tonsillectomy and adenoid removal in the risk of developing stress-related disorders in later life.

Tonsillectomy and mental disorders

Current estimates indicate that about 300,000 and 13,500 children in the United States and Sweden undergo tonsillectomy every year, respectively. The widespread prevalence of these surgical procedures necessitates a better understanding of their potential long-term complications and outcomes.

Multiple autoimmune, inflammatory, infectious or allergic, and neoplastic diseases are associated with the post-tonsillectomy state. For example, an increased risk of both irritable bowel syndrome and myocardial infarction has been reported after undergoing a tonsillectomy.

Several mechanisms have been proposed to contribute to these long-term complications. For example, the pharyngeal infection that leads to tonsillectomy may present an independent health risk.

Tonsils are important first-line defenses against inhaled or ingested pathogens; therefore, their removal may predispose affected individuals to certain diseases. Certain conditions may also underlie both the need for early-life tonsillectomy and other diseases, thus confounding the observed associations.

Children often undergo a tonsillectomy to treat recurrent tonsillitis, peritonsillar abscesses, and breathing disorders caused by obstruction of the upper respiratory tract during sleep. In adults, tonsillectomy indications include suspected cancer and obstructive sleep apnea.

Some studies have suggested that undergoing a tonsillectomy is associated with an increased risk of developing mental disorders and suicidal behavior. However, a corresponding increase in the incidence of stress-related disorders has not been examined.

This association may be related to chronic inflammation in the mucosa-associated lymphoid tissue. Some studies point to an increased risk of anxiety, depression, and stress-related illness in the presence of chronic inflammation of structures in the head and neck.

The possibility of an increased psychiatric illness risk in post-tonsillectomy children has also been suggested. In an effort to elucidate this association, the researchers of the current study determine the risk of stress-linked diseases in these individuals.

About the study

The current study included children, as well as young adults between 19 and 36 years of age, with a history of tonsillectomy or adenoidectomy with matched controls from the same nationwide population in Sweden.

A cohort of 83,957 exposed individuals was compared with a population-matched cohort of 839,570 unexposed individuals, with a mean age of 14.4 years at baseline. Another cohort of 51,601 exposed individuals and a sibling-matched cohort of 75,159 unexposed siblings, of whom the mean age was 13.3 years at baseline, were also included in the analysis.

Stress-related outcomes were identified from the Swedish Patient Register, of which included post-traumatic stress disorder (PTSD), acute stress reaction, and adjustment disorder.

Post-tonsillectomy risk of mental ill-health

Among those in the population-matched cohort who had their tonsils or adenoids surgically removed, the risk of stress-related disorders was 43% higher as compared with either siblings or other individuals who did not undergo these procedures. The risk was particularly high for PTSD, which was increased by 55%.

In the sibling-matched cohort, similar findings were obtained, with the risk of stress-related disorders and PTSD 34% and 41% higher, respectively, in exposed individuals. However, the current study did not clearly define whether the siblings shared the same environment during childhood.

This increased risk persisted after adjusting for sex, age at the time of surgery, time elapsed since surgery, educational status of the parents, and whether the parents had a history of stress-related disorders. Thus, the socioeconomic environment of the subjects did not affect their risk of developing stress-related diseases.

This increased risk was primarily associated with surgical operations for adenoidal or tonsillar disorders, as well as those used to correct breathing abnormalities. Furthermore, individuals who were older at the time of the surgery were at greater risk, as were those within ten years of the surgery.

Undergoing this type of surgical procedure is inevitably associated with unpleasant experiences including separation from parents or caregivers, hospitalization, anesthesia, and care after the procedure, all of which can contribute to short-term psychiatric risks. However, this increased risk persisted for up to 20 years after the surgery.

Conclusions

The findings suggest that early-life surgical removal of tonsils or adenoids is associated with a higher future risk of stress-related disorders.”

Tonsillectomies could present a long-term risk for psychiatric illness; however, further research is needed to explore this risk, including that of stress-related disorders. Likewise, additional studies are needed to elucidate the mechanisms involved in these associations.

It remains unclear whether the complete resolution of the illness for which the tonsillectomy was indicated affects this increased risk of psychiatric illness. Thus, the risk attributed to the surgery must be distinguished from that due to adenotonsillar disease and related conditions.