High levels of education may up brain tumour risk: study

A university degree may be linked to an increased risk of developing a brain tumour, according to a new study which found that gliomas were more common among people who had studied at college for at least three years.

Researchers from University College London in the UK and Karolinska Institutet in Sweden based their findings on more than 4.3 million Swedes, all of whom were born between 1911 and 1961 and living in Sweden in 1991.

They were monitored between 1993 and 2010 to see if they developed a primary brain tumour and information on educational attainment, disposable income, marital status and occupation was obtained.

During the monitoring period, 1.1 million people died and more than 48,000 emigrated. 5,735 of the men and 7,101 of the women developed a brain tumour, researchers said.

Men with university level education, lasting at least three years, were 19 per cent more likely to develop a glioma - a type of cancerous tumour arising in glial cells that surround and support neurons in the brain - than men whose educational attainment did not extend beyond the period of compulsory schooling (9 years), they said.

Among women, the magnitude of risk was 23 per cent higher for glioma, and 16 per cent higher for meningioma - a type of mostly non-cancerous brain tumour arising in the layers of tissue



(meninges) that surround and protect the brain and spinal cord - than it was for women who did not go on to higher education, researchers said.

High levels of disposable income were associated with a 14 per cent heightened risk of glioma among men, but had no bearing on the risk of either meningioma or acoustic neuroma - a type of non-cancerous brain tumour that grows on the nerve used for hearing and balance, they said.

Disposable income was also not associated with heightened risk of any type of brain tumour among the women. Occupation seemed to influence risk for men and women. Compared with men in manual roles, professional and managerial roles (intermediate and high non-manual jobs) were associated with a 20 per cent heightened risk of glioma and a 50 per cent heightened risk of acoustic neuroma, researchers said.

The risk of glioma was also 26 per cent higher among women in professional and managerial roles than it was for women in manual roles, while the risk of meningioma was 14 per cent higher, they said.

Single men also seemed to have a significantly lower risk of glioma than married/co-habiting men, but had a higher risk of meningioma. No such associations were evident among the women, researchers said.

The findings were published in the Journal of Epidemiology & Community Health.