Heart risk factors in middle age can reduce life span by 15 years

The new study findings are based on scrutiny of over 19,000 men aged between 40-69 years. All these men were employed in the civil service in London when they were first examined in 1967-1970 as part of the Whitehall Study.

First phase of the study

For the research purposes, researchers led by Dr Robert Clarke from the University of Oxford analysed life expectancy in relation to cardiovascular risk factors witnessed in middle age.

At the commencement of the study, that is at the entry level, the participants were made to fill in a questionnaire regarding previous medical history, smoking habits, employment grade and marital status.

Initially, the height, weight, blood pressure, lung function, cholesterol, and blood glucose levels of the participants were recorded.

Second phase of the study

The records of 18,863 men were traced and 7,044 surviving participants were again examined in 1997 i.e., almost 28 years after the initial examination was done.

When the study had started, 42 percent of the men were current smokers, 39 percent of them suffered from high blood pressure and 51 percent of them had high cholesterol levels.

After 28 years, it was found that almost two-thirds had given up smoking. Also, the mean differences in levels of blood pressure and cholesterol had dropped down by two-thirds over this time period.

Despite changes in smoking, blood pressure and cholesterol levels, the presence of these three factors recorded on a single occasion in middle aged men compared to men with no risk factors at all led to a three times higher risk of vascular mortality. Also, there was a two times higher probability of non-vascular mortality in men with heart risk factors.

When compared to men without any risk factors, the existence of all three risk factors at the entry of the study was linked to a 10 year shorter life expectancy from age 50. These figures stood at 23.7 versus 33.3 years.

The researchers also divided all the men as per a risk score that was based on all available risk factors. These factors were smoking, diabetes, employment grade, and incessant levels of blood pressure, cholesterol concentration, and body mass index.

It was found that when compared to men in the lowest five percent of this risk score, men in the highest five percent had a 15 year shorter life expectancy from age 50. These figures stood at 20.2 versus 35.4 years.