BEIJING - A research team led by Chinese scientists has linked smoking to higher risks of dementia, Health News, a national health-centric newspaper, reported on Thursday.

The research results, published in the British Occupational and Environmental Medicine journal, concluded that Environmental tobacco smoke (ETS), including smoking and passive smoking, should be considered an important risk factor for severe dementia syndromes.

The research was conducted by a team with Anhui Medical University, in cooperation with British and American scientists.

The team interviewed 5,921 people aged 60 and above in five provinces in China from 2007 to 2009. They used scientific models to calculate the relative risk of moderate and severe dementia among participants exposed to ETS.

According to the results, 626 participants, or 10.6 percent of the total, had severe dementia, and 869, or 14.7 percent, moderate syndromes.

Among them, 292 smokers or passive smokers, or 13.6 percent of participants exposed to ETS, had severe dementia, an incidence rate much higher than the 8.9 percent among the non-exposed group.

The study further found that, among those exposed to ETS for over 40 years, the risk of severe dementia escalated to 19.3 percent, showing a positive association between intensity of ETS exposure and rate of severe dementia.

The study did not find a correlation between ETS exposure and moderate dementia.

Occupational and Environmental Medicine is an international peer-reviewed journal covering developments in occupational and environmental health worldwide.