Disability and mental health among young people: effect modification by social connectedness

Abstract Background Young people with disability are more likely to have poorer mental health than young people without disability and understanding what is driving this is essential for improving mental health and reducing inequalities. Young people with disability experience lower levels of social connectedness across a range of domains, including loneliness, low social support and low frequency of social connection. Given that social connectedness is associated with poor mental health, there is a need to understand the link between different aspects of social connectedness and mental health for young people with disability. We investigated whether four aspects of social connectedness modified the magnitude of mental health inequalities between young people with and without disability. Methods We incorporated lived experience from young people with disability into all stages of the project. Using 2022 data from the Household, Income and Labour Dynamics in Australia Survey, we categorised 1,953 young people (15–24 years) by disability status, defined as no disability, psychological disability or non-psychological disability. Population-weighted linear regression models were used to estimate mean differences in mental health scores between the disability groups, including interaction terms to examine effect modification by loneliness, social support, frequency of social connection, and having a pet. Differences in mental health are interpreted as inequalities, comparing people with psychological disability or non-psychological disability to people without disability. Results Young people with psychological disability had substantially poorer mental health compared to young people without disability, while young people with non-psychological disability had some evidence of lower mental health. There was evidence of effect modification by loneliness of the inequalities in mental health between young people with psychological disability and young people without disability, with larger mental health inequalities for young people experiencing loneliness, and some suggestion of effect modification by social support and frequency of social interactions. Conclusions These findings demonstrate that the inequalities in mental health experienced by young people with psychological disability are larger when associated with loneliness and social isolation. Further research is needed to investigate causal relationships between social connectedness and mental health to better understand the directionality of effects.