The impact of smoking on the risk of developing coronary heart disease
(CHD) has been hugely underestimated, a 20 year landmark study has found. Researchers said the risk was nearly four fold higher in non smokers with high exposure to passive smoke, such as cigarette smoking by a partner, compared with non smokers with low exposure.

Study lead Professor Peter Whincup, professor of cardiovascular epidemiology at St Georges Hospital Medical School, London, said the effect of passive smoking by someone you live with was originally thought to increase the risk of CHD by 30 percent. The study followed 2,105 non smoking men from the British Regional Heart Study and measured levels of cotinine in their blood, Of these, 308 suffered a major CHD event during follow up.

During the first five years of follow-up, patients with the highest level of cotinine in the blood had nearly 4 times the risk of having a cardiac event compared with those who registered the lowest levels of nicotine.

Dr Mike Kirby, a GP and member of the Primary Care Cardiovascular Society, said GPs and practice nurses could use the results to call passive smokers in for a cardiac risk assessment. “The results are quite useful because it gives us something definite to tell the patients and in this evidence-based environment, it could be used to focus our resources, he added.

Source: Pulse, 29 September 2003