Children who undergo the surgical removal of their tonsils (tonsillectomy) with or without the removal of their adenoids (adenoidectomy) are at increased risk for becoming overweight in the years after surgery, according to a report in the journal Pediatrics.

Prior research has linked tonsillectomy to accelerated weight gain, but whether it is a risk factor for becoming overweight was unclear, note Dr. Alet H. Wijga, from the National Institute for Public Health and the Environment, Bilthoven, the Netherlands, and colleagues.

To investigate this relationship, the research team analyzed data from 3963 children enrolled in the Dutch Prevention and Incidence of Asthma and Mite Allergy (PIAMA) birth cohort study.

Annual parental questionnaires were used to assess weight, tonsillectomy status, and other factors. In addition, the height and weight of all subjects at 8 years of age was assessed by the researchers.

Tonsillectomy with or without adenoidectomy significantly increased the odds of being overweight and obese at 8 years by 61 percent and 136 percent, respectively. Adenoidectomy alone did not increase the risk of becoming overweight, but it did increase the risk of obesity by 94 percent.

Overweight status at 2 years of age was not linked to subsequent tonsillectomy, suggesting that the operation led to overweight and obesity and not vice-versa.

"Longitudinal data on weight and height in the years before and after surgery," the authors note, "suggest that (adeno) tonsillectomy forms a turning point between a period of growth faltering and a period of catch-up growth," which may explain the increased risk of becoming overweight and explain the increased risk of becoming overweight after the operation.

Based on these findings, the authors recommend that dietary and lifestyle advice be given to parents whose children are undergoing tonsillectomy. Growth monitoring after surgery is key to ensure that catch-up growth occurs within healthy limits, they add.