The common childhood removal of the tonsils or adenoids in the throat also increased the chances of allergic conditions and skin and eye diseases as well, Australian researchers found.

This is likely to be because the tissues play an important role in the early immune system, detecting and blocking the invasion of bacteria and viruses into the lungs and throat.

They are often removed if they’re obstructing easy breathing, or where they are causing repeated bouts of tonsillitis and middle-ear infections.

But the authors of this latest study say alternatives to surgery should be considered because of the increased risk of all types of infection.

“Risks were significant for many diseases and large for some,” after surgery, the authors write in the Journal of the American Medical Association, Otolaryngoloygy.

The study used health records from 1.2 million Danish children between 1979 and 1999, of which 60,400 had a tonsillectomy, adenoidectomy, or combined surgery.

It looked at these same children in their 30s and found patients who had a childhood tonsillectomy tripled their risks of infections of the upper airways like colds, rhinitis and bronchitis, compared to people who kept their tonsils.

The risk of asthma and pneumonia were also increased by roughly 50 per cent in people who had the surgery.

Because these infections are already common in the community, the extra impact of having your tonsils out could be "considerable", the authors said.

"Our results show increased risks for long-term diseases after surgery, support delaying tonsil and adenoid removal if possible, which could aid normal immune system development in childhood and reduce these possible later-life disease risks,” said the study's lead author, Dr Sean Byers from the University of Melbourne.

"As we uncover more about the function of immune tissues and the lifelong consequences of their removal, especially during sensitive ages when the body is developing.”

Removal of the adenoids, the tissue at the back of the roof of your mouth under the nasal cavity, doubled the risk of chronic obstructive pulmonary disease, which includes emphysema and asthma.

However these conditions are much rarer than respiratory tract infections overall – 0.25 per cent of the general population in their 30s have some form of COPD – so the impact is less pronounced.

The authors said it was perhaps “not surprising” that removing these key parts of the body's immune system might undermine detection and susceptibility to respiratory infections.

But they also found heightened susceptibility to 28 different types of disease, including parasitic infections, skin diseases and eye complaints – 78 per cent of these were experienced more commonly in people who had these surgeries.

These are unrelated to the airways and suggest there is some knock-on impact on the immune system from the loss of your tonsils or from the repeated minor infections this brings – this may become even more pronounced as the population ages.

"Our results show increased risks for long-term diseases after surgery, support delaying tonsil and adenoid removal if possible, which could aid normal immune system development in childhood and reduce these possible later-life disease risks,” said lead author Dr Shaun Bayers, from the University of Melbourne.

"As we uncover more about the function of immune tissues and the lifelong consequences of their removal, especially during sensitive ages when the body is developing.”

Tim Mitchell, a consultant otolaryngologist and council member of the Royal College of Surgeons, said the findings were interesting and "certainly warrant further investigation".

“Before opting to remove tonsils or adenoids, surgeons will always consider and discuss all treatment options, including non-surgical treatments, with patients, and parents in the case of children," he said.

"There has been a significant decrease in the number of tonsillectomies and adenoidectomies performed in the last few decades."

The Independent 

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