It is already well known that people with higher social status have lower risk of coronary heart disease. This trend is not fully explained by differences in lifestyle factors such as smoking and lack of exercise.
But speaking at the European Society of Cardiology meeting this week, Danish researchers said that people in the lowest socioeconomic position were also 2.5 times more likely to have metabolic syndrome than those in the highest position.
Metabolic syndrome is a cluster of risk factors for heart disease, including high cholesterol levels, high blood pressure and obesity.
Their study, carried out between 2001-2003, was based on 6038 randomly selected healthy men and women living in Copenhagen. Approximately 20 per cent of these had metabolic syndrome.
But among individuals with the highest level of education (of five levels) only 10 per cent had the condition compared to 26 per cent of those with the lowest level of education.
Individuals with a higher level of education were at considerably lower risk of having all of the factors included in the metabolic syndrome: abdominal obesity, hyperlipidemia, hypertension, high blood-glucose, c-reactive protein and fibrinogen, said author E. Prescott.
Because it has been suggested that some of the social gradient in heart disease is caused by differences in psychosocial factors such as perceived stress, depression and lack of social network, the Danish researchers explored distribution of psychosocial factors in the Copenhagen group.
They found that individuals with a lower level of education scored higher on the depression/fatigue scale and had poorer social networks but there was no difference in reporting of perceived stress.
As in most other studies, individuals with higher level of education tended to have a healthier lifestyle: they smoked less and exercised more but also drank more alcohol.
But even after taking differences in lifestyle or psychosocial factors into account, individuals with the highest level of education still had a 60 per cent lower risk of having the metabolic syndrome. This is equal to a 2.5 higher risk of metabolic syndrome in the lowest socio-economic position compared to the highest.
"In conclusion, this study confirms that cardiovascular risk factors tend to accumulate with lower socio-economic position. This is particularly true for the cluster of risk factors in the metabolic syndrome," said Dr Prescott.
Although both psychosocial stressors and lifestyle factors such as smoking, lack of exercise and alcohol consumption are important in linking social position and cardiovascular health, these risk factors do not offer simple answers for how individuals at lower social positions are at increased risk for the metabolic syndrome, noted the researchers.