OBJECTIVES: The level of an individual’s physical activity has a clear and strong association with physical and mental health status. Those with sedentary lifestyles or with low levels of physical activity are at a higher risk of many conditions including coronary heart disease, stroke, cancer and depression. We aimed to estimate the health economic impact associated with different levels of increases in physical activity for people with limited mobility.

METHODS: We used national health survey data to estimate the current level of physical activity in people with limited mobility (n=1113), and how these levels changed after an intervention was introduced. Limited mobility was defined as having either ‘Some problems in walking about’ or ‘Confined to bed’ on the mobility component of the EQ-5D questionnaire. The level of physical activity was measured using metabolic equivalent time (MET) minutes, a measure that combines the time spent exercising with the level of vigour involved. We used information from published studies to estimate the risk of developing five health conditions (breast and colon cancer, diabetes, stroke and coronary heart disease), depending on MET level. Costs, utilities and mortality rates were assigned to each of these conditions, to estimate the lifetime costs and quality-adjusted life years for a range of scenarios.

RESULTS: Interventions that cost £25, £100 and £250 per person would need to increase physical activity by approximately 4, 16 and 41 MET minutes per week respectively to be deemed cost effective. Sensitivity analysis showed that changes to cost, utility and mortality input parameters had minimal impact on these results.

CONCLUSIONS: Even small increases in physical activity can generate substantial health gains in a population with limited mobility. Whilst the benefits need to be weighed against the implementation costs, it is likely that most public health strategies to facilitate activity in this population will be cost effective.