The effect of gender and age on the association between weight status and health-related quality of life in Australian adolescents

Background: Evidence suggests an inverse relationship between excess weight and health-related quality of life (HRQoL) in children and adolescents, however little is known about whether this association is moderated by variables such as gender and age. This study aimed to investigate these relationships. Methods: Participants were secondary school students (818 females, 52% and 765 males, 48%) from 23 secondary schools in Victoria, Australia. Age ranged from 11.0 to 19.6 years (mean age 14.5 years). The adolescent version of the Assessment of Quality of Life (AQoL) Instrument (AQoL-6D) which is a self-reported measure of adolescent quality of life was administered and anthropometric measures (height and weight) were taken. Assessment of weight status was categorized using the Body Mass Index (BMI). Results: HRQoL was associated with gender and age, but not weight status or socio economic status; with males and younger adolescents having higher HRQoL scores than their female and older adolescent counterparts (both p < 0.05). There was also a significant interaction of weight status by gender whereby overweight females had poorer HRQoL (-.06 units) relative to healthy weight females (p < 0.05). Conclusions: This study contributes to the evidence base around factors associated with adolescent HRQoL and reveals that gender and age are important correlates of HRQoL in an Australian adolescent population. This knowledge is critical to inform the design of health promotion initiatives so they can be tailored to be gender- and age-specific. Trial registration: Australian Clinical Trials Registration Number 12609000892213.