Association of childhood residential environment and family socioeconomic status with physical activity in early adulthood - a population-based Northern Finland Birth Cohort 1986 study

BACKGROUND: Higher socioeconomic status is associated with more physical activity in both childhood and adulthood. There is conflicting evidence about the importance of the urban and rural residential environment on children's physical activity. The family socioeconomic status and urban-rural residential area may have combined associations with children's physical activity, but the evidence so far is scarce, and has mainly come from cross-sectional studies. METHODS: We used population-based cohort data from the Northern Finland Birth Cohort 1986 (NFBC1986). Participants (n = 9432) parents reported the family's urban or rural residential environment and family socioeconomic status (SES) was based on the parents' employment status and education level in years 1992 or 1993 when the participants were 7 years old. In 2019-2020, at around 35 years old, participants underwent clinical examinations and answered questionnaires regarding their health, health behaviour and SES. Physical activity data, including time spent in light and moderate-to-vigorous physical activity, were collected with the Ōura ring. We used linear regression and two-way ANCOVA to study the associations of the childhoods rural and urban residential environment and socioeconomic status with different physical activity intensity levels in adulthood. RESULTS: High family SES children who lived in a rural area during childhood were more physically active in adulthood than those high family SES children who lived in an urban area during childhood. Statistically significant associations were found in total physical activity (TPA) and light physical activity (LPA) only in men. According to linear regression analyses the difference in TPA was in the unadjusted model 50 min per day greater in those high family SES men who lived in rural area in childhood (95 % CI = 19, 63, p < 0.001) compared with their urban counterparts. When model was adjusted with BMI, work strenuousness and adulthood residential environment (urban/rural) the difference was 27 min (95 % CI = 1, 53, p = 0.043). For LPA, in the unadjusted model, the difference was 40 min more per day for high family SES men who lived in rural areas during childhood (95 % CI = 20, 61, p < 0.001) and in the adjusted model 28 min (95 % CI = 4, 51, p = 0.023) more per day compared with high childhood family SES men in urban area. CONCLUSIONS: In promoting an active lifestyle, it is important to consider both the household and parental socioeconomic situation and the residential environment individuals are exposed to from an early age.