Do differences in social support explain the social inequality in sedentary lifestyle among adolescents?

Background
Many studies have demonstrated increasing prevalence of
sedentary lifestyle among adolescents with decreasing socioeconomic
position but few have attempted to explain this
social inequality. The objective of this study was to examine
if social support contributed to the explanation of social
inequalities in sedentary lifestyle.
Methods
The study population was all 11-, 13-, and 15-year-old students
in a random sample of schools in Denmark, n ¼ 4.824. We
collected data with the internationally 2002 standardized HBSC
questionnaire and used the following measures: (i) SEP defined
by parents’ occupation from I (high) to VI (low); (ii) sedentary
lifestyle defined as 0 h of leisure time physical activity; (iii) social
support defined by confidant relations with parents, confidant
relations with friends, and no exposure to bullying.
Results
The prevalence of sedentary lifestyle was 10.2%. The sex- and
age-adjusted OR (95% CI) for sedentary lifestyle was 1.16 (0.89–
1.51) in SEP III-IV and 1.75 (1.30–2.35) in SEP V-VI (reference
group: SEP I-II). Lack of confident relations with parents and
friends and exposure to bullying were significant predictors
of sedentary lifestyle. The OR-values remained unchanged
when included in a multivariate model, i.e. there was no
statistical mediation. There was statistically significant interaction
between SEP and social support, i.e. the association between
SEP and sedentary lifestyle was stronger among students with
low than high social support.
Conclusions
Social support reduced the effect of low socioeconomic position
on sedentary lifestyle among adolescents in this cross-sectional
study.