Men of lower social class, income or education have twice the risk of dying during middle age compared with their counterparts with higher socioeconomic status, new study findings show. Up to about half of the excess deaths may be due to smoking, based on extrapolation of data regarding lung cancer rates in different countries.

To discern the origin of the increased death risk among men ages 35 to 69 of lower socioeconomic status, Dr. Prabhat Jha, from the University of Toronto, and colleagues analyzed data from four countries for 1996. Their findings appear in The Lancet.

They determined the top and bottom social strata based on occupation (professional versus unskilled manual labor) in England and Wales, neighborhood income in Canada, and years of education in the US and Poland.

The investigators then estimated the death risk attributable to smoking based on age-specific lung cancer rates and other diseases associated with smoking, among about 564,000 men.

As noted, the death rate was twice as high among men in the lower strata versus those in the highest. The proportion of deaths caused by smoking ranged from 38 percent in Canada to 45 percent in Poland.

Jha’s group notes, “a substantial increase in smoking cessation could approximately halve these 1996 social inequalities in adult male” deaths.

In a related commentary, Dr. Michael Marmot from University College London writes: “Social gradient in (death risk) is the result of differences in the social circumstances in which people live and work.”

He cautions that the adverse effects of “social conditions, neighborhood deprivation, employment conditions, early childhood and subsequent adult disease” should not be forgotten in efforts to reduce smoking rates.

SOURCE: The Lancet, July 14th online issue, 2006.