Additive and interactive effects of social, financial and environmental factors on gait speed among community dwelling older adults in Nigeria: A cross-sectional study

Gait speed is considered the sixth vital sign in geriatric care, due to its predictive role in health and social outcomes. Although various factors influence gait speed, environmental and social factors are frequently overlooked, particularly in developed regions with distinct cultural perspectives. The study examines how these environmental, financial and social factors additively or interactively influence gait speed of community dwelling older adults in Nigeria. We employed a cross-sectional study design included 408 community-dwelling older adults (mean [S.D] = 68.0(6.6) years) from a city in Nigeria. We administer validated measures to assess nine neighborhood environmental factors, five social factors and self-reported income. Gait Speed was assessed using the 10-metre walk test and categorized < 0.8m/s (slow speed) and ≥0.8m/s (normal). Logistic regression analysis was used to determine the predictors of gait speed in this dichotomized form. Slow gait speed prevalence was 72.4%. The additive model revealed that age (OR = 0.798, p < 0.001), social network (OR = 1.079, p < 0.01), and neighborhood surroundings (OR = 1.117, p < 0.01) were significant predictors of high gait speed. In the interaction model, age, social network, and neighborhood surroundings remained significant predictors and education level became significant: secondary education (OR = 3.986, p = 0.047) and tertiary education (OR = 4.580, p = 0.038) associated with higher odds of high gait speed. Findings suggest that enhancing social networks and improving neighborhood environments may be crucial in promoting better mobility outcomes, particularly among diverse older adults.