Five Years of Lifestyle Intervention Improved Self-reported Mental and Physical Health in a General Population: the Inter99 Study

Introduction: Self-reported health has been shown to predict mortality. We lack knowledge on whether a lifestyle intervention can improve self-reported mental and physical health in a general population.

Methods: Inter99, Denmark (1999-2006) is a randomised population-based intervention study. We screened for ischemic heart disease and repeatedly offered advice and assistance to obtain a healthier lifestyle. Health related quality of life was measured by Short Form 12 (SF-12); completed by 9322 at baseline and 7719 at five-year follow-up. In linear mixed models we investigated the effect of the intervention on self-reported health over time.

Results: At baseline men had higher physical health-component scores (PCS) than women. Living with a partner, being employed, and being healthy was associated with high PCS. The mental health-component scores (MCS) showed the same socio-demographic differences, except that MCS increased with age. Significantly fewer participants in the intervention groups had decreased their PCS and MCS compared with the control group. Adjusted multilevel analyses confirmed that the intervention significantly improved physical- (p=0.008) and mental health (p<0.001) over time compared with the control group.

Conclusion: Screening for ischemic heart disease and offering lifestyle intervention had a significantly beneficial effect on mental and physical self-reported health in the long term in a general population.