Determinants of mobility in community-dwelling older adults: a network analysis before, during and two years after the onset of the COVID-19 pandemic.

BACKGROUND We conceptualized out-of-home mobility as life space mobility and autonomy outdoors. Both are correlated with quality of life and influenced by multiple underlying factors. We used a complex systems approach and network models to explore changes in networks consisting of out-of-home mobility indicators and their determinants before, during and two years after the onset of the COVID-19 pandemic. METHODS Participants were older adults aged 75, 80 and 85 years at baseline (2017-2018), with follow-ups in 2020 and 2021-2022 (n = 607). Life-space mobility, autonomy outdoors, and socio-demographic, physical, psychosocial, financial, and environmental determinants were assessed using the same validated scales at all three time points. Mixed graphical model networks were estimated for each time point. Differences in network properties and the relative importance of determinants associated with life-space mobility and autonomy outdoors were compared across time points. RESULTS During the COVID-19 pandemic, both life-space mobility and autonomy outdoors declined (p < 0.05). Throughout the follow-up, walking difficulty and sex remained consistently associated with life-space mobility and psychosocial factors with autonomy outdoors. At the onset of the pandemic, being female (vs. male) was more strongly associated with reduced autonomy outdoors than at other times, while the associations with older age and poorer health were weaker. CONCLUSIONS The pandemic reduced older adults' out-of-home mobility and altered the factors underlying it. During the pandemic, environmental support for out-of-home mobility diminished as destinations of interest for older people were closed. This especially affected women, potentially leading to less favorable participation trajectories in the future.