Disability acquisition and mental health: effect modification by demographic and socioeconomic characteristics using data from an Australian longitudinal study

Trends in mental health inequalities for people with disability, Australia 2003 to 2020

OBJECTIVE

Cross-sectional studies have demonstrated that people with disability have substantial inequalities in mental health compared to people without disability. However, it is not known if these inequalities have changed over time. This study compared the mental health of people with and without disability annually from 2003 to 2020 to investigate time trends in disability-related mental health inequalities.

METHODS

We use annual data (2003-2020) of the Household, Income and Labour Dynamics in Australia Survey. Mental health was measured using the five-item Mental Health Inventory. For each wave, we calculated population-weighted age-standardised estimates of mean Mental Health Inventory scores for people with and without disability and calculated the mean difference in Mental Health Inventory score to determine inequalities. Analyses were stratified by age, sex and disability group (sensory or speech, physical, intellectual or learning, psychological, brain injury or stroke, other).

RESULTS

From 2003 to 2020, people with disability had worse mental health than people without disability, with average Mental Health Inventory scores 9.8 to 12.1 points lower than for people without disability. For both people with and without disability, Mental Health Inventory scores decreased, indicating worsening mental health, reaching the lowest point for both groups in 2020. For some subpopulations, including young females and people with intellectual disability, brain injury or stroke, mental health inequalities worsened.

CONCLUSION

This paper confirms that people with disability experience worse mental health than people without disability. We add to previous findings by demonstrating that disability-related inequalities in mental health have been sustained for a long period and are worsening in some subpopulations.

Disability-related inequalities in health and well-being are mediated by barriers to participation faced by people with disability. A causal mediation analysis

Large inequalities in health and well-being exist between people with and without disability, in part due to poor socio-economic circumstances, and potentially also related to societal factors including issues associated with accessibility and participation. To better understand the contribution of societal factors, we used a unique longitudinal survey of disability in Great Britain to quantify the extent to which barriers to participation contribute to poorer health and well-being. We used data from 2354 individuals who participated in three waves of the Life Opportunities Survey between 2009 and 2014 and compared five health and well-being outcomes (self-rated health, anxiousness, life satisfaction, life worth, happiness) between adults who acquired an impairment and those who remained disability-free. Causal mediation analysis was conducted to quantify how much of the effect of disability acquisition on each outcome was explained by barriers to participation in employment, economic life, transport, community, leisure and civic activities, social contact, and accessibility. People who recently acquired a disability had poorer health and well-being compared to people with no disability. Barriers to participation explained 15% of inequalities in self-rated health, 28% for anxiousness, 32% for life satisfaction, 37% for life worth, and 70% for happiness. A substantial proportion of the inequalities in health and well-being experienced by people with recently acquired disability were socially produced, driven by barriers to participation in different life domains. Furthermore, there was evidence that barriers to participation mediated the effect of well-being measured to a greater extent than the more clinically aligned measures, self-reported health and anxiousness. These findings highlight modifiable factors amenable to public health interventions that could lead to substantial improvements in health and well-being for people with disability.

Social Risk Factors Are Associated With Disability Prevalence - Results From 17 States in the 2017 Behavioral Risk Factor Surveillance System

PURPOSE

Determine the association between incremental increases in the number of social risk factors and the prevalence of any disability and disability type.

DESIGN

The cross-sectional analysis was conducted using 2017 Behavioral Risk Factor Surveillance System data from states whose surveys included items about social risk factors.

SETTING

Respondents from 17 US states.

SUBJECTS

Respondents included 136 432 adults.

MEASURES

Dichotomized social risk factors included food, housing, and financial insecurity, unsafe neighborhood, and healthcare access hardship.

ANALYSIS

Weighted χ² and logistic regression analyses adjusted for demographic characteristics, measures of socioeconomic position, and comorbid health conditions were used to examine differences in the prevalence of disability by social risk factor and via a social risk index created by summing the social risk factors.

RESULTS

Compared to those reporting 0 social risk factors, respondents reporting ≥4 had more than thrice the odds of reporting a cognition ((adjusted odds ratio [AOR]=3.37; 95%CI [2.75-4.13]), independent living (AOR=3.24 [2.52-4.15]), self-care (AOR=3.33 [2.55-4.34]), or any disability (AOR=3.90 [3.24-4.70]); more than twice the odds of reporting a vision (AOR=2.61 [1.93-3.52]) or mobility (AOR=2.72 [2.16-3.41]) disability; and more than 1.5 times the odds of reporting a hearing disability (AOR=1.59 [1.22-2.07]).

CONCLUSIONS

Incremental increases in the number of social risk factors were independently associated with higher odds of disability. Intervention efforts should address the social context of US adults with disabilities to improve health outcomes.

How much of the effect of disability acquisition on mental health is mediated through employment and income? A causal mediation analysis quantifying interventional indirect effects using data from four waves of an Australian cohort study

OBJECTIVES

There is evidence that disability acquisition causes a decline in mental health, but few studies have examined the causal mechanisms through which the effect operates. This study used a novel approach to mediation analysis to quantify interventional indirect effects (IIEs) through employment and income.

DESIGN AND SETTING

We used four waves of longitudinal data (2011-2014) from the Household, Income and Labour Dynamics in Australia Survey, a nationally representative survey of Australian households.

PARTICIPANTS

Working aged individuals who acquired a disability (n=233) were compared with those who remained disability-free in all four waves (n=5419).

PRIMARY OUTCOME MEASURE

Self-reported mental health was measured using the Mental Health Inventory subscale of the Short Form 36 general health questionnaire, which measures symptoms of depression, anxiety and psychological well-being.

STATISTICAL ANALYSIS

We conducted a causal mediation analysis quantifying IIEs of disability acquisition on mental health operating through two distinct mediators: employment status and income. We used multiple imputation with 50 imputed datasets to account for missing data.

RESULTS

The total causal effect of disability acquisition on mental health was estimated to be a 4.8-point decline in mental health score (estimated mean difference: -4.8, 95% CI -7.0 to -2.7). The IIE through employment was estimated to be a 0.5-point difference (-0.5, 95% CI -1.0 to 0.0), accounting for 10.6% of the total effect, whereas there was no evidence that income explained any of the effects.

CONCLUSIONS

This study estimated that disability-related mental health inequalities could be reduced by 10.6% if employment rates were the same for people with disability as those without disability. The results suggest that employment is implicated in the relationship between disability acquisition and mental health and that more research is needed to understand the influence of other aspects of employment and other socioeconomic characteristics.

Vocational Interventions to Improve Employment Participation of People with Psychosocial Disability, Autism and/or Intellectual Disability: A Systematic Review

Objective: To systematically review interventions aimed at improving employment participation of people with psychosocial disability, autism, and intellectual disability. Methods: We searched MEDLINE, Embase, PsycINFO, Web of Science, Scopus, CINAHL, ERIC, and ERC for studies published from 2010 to July 2020. Randomized controlled trials (RCTs) of interventions aimed at increasing participation in open/competitive or non-competitive employment were eligible for inclusion. We included studies with adults with psychosocial disability autism and/or intellectual disability. Risk of bias was assessed using the Cochrane Collaboration Risk of Bias II Tool. Data were qualitatively synthesized. Our review was registered with PROSPERO (CRD42020219192). Results: We included 26 RCTs: 23 targeted people with psychosocial disabilities (n = 2465), 3 included people with autism (n = 214), and none included people with intellectual disability. Risk of bias was high in 8 studies, moderate for 18, and low for none. There was evidence for a beneficial effect of Individual Placement and Support compared to control conditions in 10/11 studies. Among young adults with autism, there was some evidence for the benefit of Project SEARCH and ASD supports on open employment. Discussion: Gaps in the availability of high-quality evidence remain, undermining comparability and investment decisions in vocational interventions. Future studies should focus on improving quality and consistent measurement, especially for interventions targeting people with autism and/or intellectual disability.

Australia's Disability Employment Services Program: Participant Perspectives on Factors Influencing Access to Work

Disability employment programs play a key role in supporting people with disability to overcome barriers to finding and maintaining work. Despite significant investment, ongoing reforms to Australia's Disability Employment Services (DES) are yet to lead to improved outcomes. This paper presents findings from the Improving Disability Employment Study (IDES): a two-wave survey of 197 DES participants that aims to understand their perspectives on factors that influence access to paid work. Analysis of employment status by type of barrier indicates many respondents experience multiple barriers across vocational (lack of qualifications), non-vocational (inaccessible transport) and structural (limited availability of jobs, insufficient resourcing) domains. The odds of gaining work decreased as the number of barriers across all domains increased with each unit of barrier reported (OR 1.22, 95% CI 1.07, 1.38). Unemployed respondents wanted more support from employment programs to navigate the welfare system and suggest suitable work, whereas employed respondents wanted support to maintain work, indicating the need to better tailor service provision according to the needs of job-seekers. Combined with our findings from the participant perspective, improving understanding of these relationships through in-depth analysis and reporting of DES program data would provide better evidence to support current DES reform and improve models of service delivery.

Does the effect of disability acquisition on mental health differ by employment characteristics? A longitudinal fixed-effects analysis

PURPOSE

Longitudinal studies have suggested a causal relationship between disability acquisition and mental health, but there is substantial heterogeneity in the magnitude of the effect. Previous studies have provided evidence that socioeconomic characteristics can buffer the effect but have not examined the role of employment characteristics.

METHODS

We used data from 17 annual waves of the Household, Income and Labour Dynamics in Australia Survey to compare the mental health of working age individuals before and after disability acquisition, using the Mental Health Inventory, a subscale of the SF-36 health questionnaire. Linear fixed-effects regression models were used to estimate the effect of disability acquisition on mental health. We tested for effect modification by two characteristics of people's employment prior to disability acquisition: occupational skill level and contract type. Multiple imputation using chained equations was used to handle missing data.

RESULTS

Disability acquisition was associated with a substantial decline in mental health score (estimated mean difference: - 4.3, 95% CI - 5.0, - 3.5). There was evidence of effect modification by occupational skill level, with the largest effects seen for those in low-skilled jobs (- 6.1, 95% CI - 7.6, - 4.5), but not for contract type.

CONCLUSIONS

The findings highlight the need for social and health policies that focus on increasing employment rates, improving the sustainability of employment, and providing employment services and education and training opportunities for people who acquire a disability, particularly for people in low-skilled occupations, to reduce the mental health inequalities experienced by people with disabilities.

Disabling working environments and mental health: A commentary

Employment is a fundamental Social Determinant of Health known to have large impacts on mental health and other health outcomes. Across many countries of the world, people with disabilities are much more likely to be unemployed and looking for work than those without disabilities. The deprivation of employment opportunities is likely to have notable impacts on the health of people with disabilities. In this commentary, we outline the concept of "disabling working environments," which are defined as the range of experiences that affect the likelihood of people with disabilities in obtaining and maintaining quality employment which may then affect a disabled person's health. Disabling working environments are comprised of the following three mutually reinforcing components: 1) Differential selection into work; 2) Selection into certain types of jobs and exposure to poor psychosocial working environments when in employment, and; 3) Differential selection out of work (e.g., leaving employment at an earlier age than those who do not have a disability). We argue that policy and intervention design should consider the life course effects of employment on the mental health of people with disabilities.