A study shows that having tonsils removed during childhood is linked to a greater risk of arthritis in old age.
Those who had the procedure at a young age were about a third more likely to develop a form of chronic inflammatory arthritis called ankylosing spondylitis.
People were more at risk if they had an older brother or sister, Swedish researchers found, suggesting that environmental factors in early life play a role in the disease.
The study involved almost 7,000 people with the disease diagnosed between January 2001 and December 2022.
People were analyzed according to early life risk factors, including mother’s age at delivery, weight (BMI) in early pregnancy, duration of pregnancy, baby’s birth weight and type of delivery.
Swedish experts say removing tonsils was associated with a 30 percent increased risk of developing arthritis in old age (stock image)
Other factors taken into account were the number of siblings, serious childhood infections from birth to age 15, and removal of tonsils and appendix before age 16.
Researchers found that people with older siblings had an increased risk of 12 to 15 percent, while serious childhood infections increased the risk by 13 percent.
However, tonsil removal was associated with a 30 percent increased risk of the condition, which is typically characterized by inflammation of the spine, joints and tendons, resulting in pain, stiffness and fatigue.
Being part of a multiple birth increased the risk by almost a quarter (23 percent), while being born in the summer or autumn months carried a significantly lower risk than being born in winter, according to the findings in the BMJ.
Scientists speculate that the increased risk may be due to the fact that babies with older siblings are more exposed to infections at a young age, while tonsillectomies were often performed after infections.
The researchers then conducted a comparison analysis between siblings, which adjusts for potentially influential environmental factors shared within families.
This analysis indicated an 18 percent increased risk for one older sibling compared to none, rising to 34 percent for two or more older siblings and 36 percent for those who had their tonsils removed.
The researchers concluded: ‘Having older siblings and a history of tonsillectomy in childhood were independently associated with the development of ankylosing spondylitis, even after adjusting for shared family factors in a sibling comparison analysis.
‘This strengthens the hypothesis that childhood infections play a role in the etiology of (the condition).’