Does a population-based multi-factorial lifstyle intervention increase social inequality in physical activity? The Inter99 study.
- Correspondence to: mette Aadahl, Research Centre for Prevention and Health, Ndr. Ringvej 57, Building 84/85, Glostrup, 2600, Denmark; metaad01{at}glo.regionh.dk
- Received 24 July 2009
- Accepted 3 October 2009
- Published Online First 22 October 2009
Abstract
Aim: To examine the effect of a multi-factorial lifestyle intervention on five-year change in physical activity and to explore whether length of education had an impact on the effect of the intervention.
Methods: Two random samples (High intervention group A, n=11,708; Low intervention group B, n= 1,308) were invited for a health examination, assessment of absolute risk of ischemic heart disease and individual lifestyle counselling. The participation rate was 52.5%. High-risk individuals in group A were also offered group-based councelling on diet and physical activity and/or smoking cessation. High-risk individuals in group B were referred to usual care. All high-risk individuals were re-invited for examination and counselling after one and three years, and all participants were re-examined after five years. The control group (Group C, n=5,264, response rate 61.3%) answered a mailed questionnaire. Change in self-reported physical activity from baseline to five-year follow-up was the main outcome. Level of education was classified as: no vocational training, ≤ 4 years, and > 4 years. Data were analysed using longitudinal linear regression models with random intercepts.
Results: In men, the high-intensity intervention had a beneficial effect on physical activity level after five years. The age- or time-related decrease in physical activity was approximately 30 min/week less compared to men in the control group (p< 0.0001). Level of education had no significant impact on the effect of the intervention neither in men (p=0.39) nor in women (p=0.32).
Conclusion: A population-based multi-factorial lifestyle intervention did not influence social inequality in physical activity.
