Clustering of behavioural risk factors and their association with subjective health

objectives: to describe the clustering of behavioural risk factors in the adult population of the autonomous community of madrid (spain), and to evaluate the association between the level of aggregation of such factors and suboptimal subjective health. methods: data were drawn from the non-communicable disease risk-factor surveillance system (sistema de vigilancia de factores de riesgo asociados a enfermedades no transmisibles - sivfrent). we studied the relationships between tobacco use, high-risk alcohol consumption, leisure-time inactivity and unbalanced diet in 16,043 people aged 18-64, comparing observed against expected proportions. logistic regression was used to estimate the association between aggregation of risk factors and suboptimal health (fair, poor and very poor health). results: almost 20% of subjects had 3 or 4 risk factors. most combinations of three risk factors exceeded expectations and, in particular, 4-factor clustering yielded observed/expected quotients of 2.15 (95% confidence interval [ci], 1.93-2.38) in men and 2.96 (95% ci, 2.46-3.46) in women. in both sexes, smoking was the individual factor most frequently associated with the remaining risk factors. aggregation of risk factors was more frequent among men, in younger age groups and among subjects with low educational level. compared to people with none of the 4 risk factors, those with 3 or four reported suboptimal subjective health more frequently (or = 2.49; 95% ci, 1.59-3.90 for men and or = 1.96; 95% ci, 1.29-2.97 for women). conclusions: behavioural risk factors tend to aggregate, and this clustering is higher among men, in younger age groups and among subjects with a low educational level. a greater level of clustering is associated with a higher frequency of suboptimal self-rated health.