The findings in the European Journal of Cardiovascular Prevention and Rehabilitation indicate that lower scores are associated with higher rates of cardiovascular disease and total mortality.

These conclusions have been derived from study designed to investigate the influence of social factors on health. For the analysis based on data collection of a 1145 member group aged around 55, the figures were collected for height, weight, blood pressure, smoking habits, physical activity, education and occupation.

The results applied to statistical model to quantify the associations of nine risk factors with cardiovascular mortality, showed the most important was cigarette smoking, followed by low IQ.

The relative index of inequality which summarized as the relative risk of cardiovascular death in the most disadvantaged people relative to the low risk was found to be 5.58 for cigarette smoking, 3.76 for IQ, 3.20 for low income,
2.61 for high systolic blood pressure, and 2.06 for low physical activity.

Lead author Dr David Batty, based at the MRC research unit in Glasgow, said it may be that people with low IQ are less likely to follow a healthy lifestyle or that they had suffered problems early in life that affected both their intellect and health.