The relationship between living at moderate altitude and the loss of autonomy and independence in elderlies: a French longitudinal study.

Introduction: A loss of autonomy and independence are clearly identified for the majority of aging people, with a significant impact at the individual and society levels. Permanent residency at moderate altitude appears to be associated with beneficial health effects. This study aimed at determining changes in dependency and autonomy in elderlies depending on their altitude of residence in a French Alps area.

Methods: We retrospectively analyzed longitudinal data from 9 863 elderlies initially residing at home, at <500m, 500-900m or >900m above sea level, and presenting with a mild reduction in autonomy and independence. Over a 5-year period, changes in GIR score (an index of autonomy and independence ranging from 6 to 1, the lower the score the more severe the loss of autonomy and independence) annually collected in elderlies by the local authority, and potential transfer to an institution, were analyzed.

Results: After 5 years of follow-up, elderlies living at higher altitude showed a significantly larger GIR score reduction (p = 0.04). The time required to lose one GIR level tended to be shorter in elderlies living at moderate altitude. Elderlies residing at moderate altitude were institutionalized significantly later that those living at lower altitude (p < 0.01).

Conclusion: These results do not support a positive effect of residing at moderate altitude on elderly autonomy and independence, the latter being likely influenced by a combination of environmental, behavioral and social factors.