Associations between neighbourhood environmental factors and the uptake and effectiveness of a brief intervention to increase physical activity: findings from deprived urban communities in an English city.

Background: Evidence suggests behavioural interventions may exacerbate health inequalities, potentially due to differences in uptake or effectiveness. We used a physical activity intervention targeting deprived communities to identify neighbourhood-level factors that might explain differences in programme impact. Methods: Individuals aged 40-65 were sent a postal invitation offering a brief intervention to increase physical activity. We used postcodes linkage to determine whether neighbourhood indicators of deprivation, housing, crime and proximity to green spaces and leisure facilities predicted uptake of the initial invitation or an increase in physical activity level in those receiving the brief intervention. Results: A total of 4134 (6.8%) individuals responded to the initial invitation and of those receiving the intervention and contactable after 3 months, 486 (51.6%) reported an increase in physical activity. Area deprivation scores linked to postcodes predicted intervention uptake, but not intervention effectiveness. Neighbourhood indicators did not predict either uptake or intervention effectiveness. Conclusions: The main barrier to using brief intervention invitations to increase physical activity in deprived, middle-aged populations was the low uptake of an intervention requiring significant time and motivation from participants. Once individuals have taken up the intervention offer, neighbourhood characteristics did not appear to be significant barriers to successful lifestyle change.