A large scale study in Sweden shows that children who have their tonsils removed - a common procedure - are more likely to exhibit PTSD and anxiety-related illnesses in later life. Hat tip to Instapundit for the link.
[Scientists] analyzed data on over a million people held in a Swedish health registry, finding that a tonsillectomy was linked to a 43 percent increased risk of developing conditions such as post-traumatic stress disorder (PTSD), depression, or anxiety.
Being an observational study, the research can't determine the cause of this outcome, however the increased risk was present even after accounting for the sex of the participants, the age at which they had their tonsils out, any family history of stress-related disorders, and the education level of the parents (an indicator of socioeconomic status).
The researchers compared children who had tonsils removed to their siblings who had not had the procedure. Those with the operation had a 34% greater risk of anxiety disorders than their sibs who still had their tonsils.
These effect sizes are large and must mean something, though what exactly remains unclear. Some possibilities: surgical trauma, anesthesia poisoning, antibody shortfalls, the effects of chronic illness on childhood ego development?
Full disclosure: Mine were not removed.
