Is equity considered in systematic reviews of interventions for mitigating social isolation and loneliness in older adults?

Abstract

Background: Social isolation and loneliness affect one in four older adults in many regions around the world. Social isolation and loneliness are shown to be associated with declines in physical and mental health. Intersecting social determinants of health influence both the risk of being socially isolated and lonely as well as the access and uptake of interventions. Our objective is to evaluate what evidence is available within systematic reviews on how to mitigate inequities in access to and effectiveness of interventions.

Methods: We performed an overview of reviews following methods of the Cochrane Handbook for Overviews of Reviews. We selected systematic reviews of effectiveness of interventions aimed at mitigating social isolation and loneliness in older adults (aged 60 or above) published in the last 10 years. In addition, we assessed all primary studies from the most recent systematic review with a broad intervention focus. We searched MEDLINE, EMBASE, PsycINFO, CINAHL, and Scopus in collaboration with a librarian scientist. We used a structured framework called PROGRESS-Plus to assess the reporting and consideration of equity. PROGRESS-Plus stands for place of residence, race/ethnicity/culture/language, occupation, gender or sex, religion, education, socioeconomic status (SES), social capital, while "plus" stands for additional factors associated with discrimination and exclusion such as age, disability, and sexual orientation. We assessed whether PROGRESS-Plus factors were reported in description of the population, examination of differential effects, or discussion of applicability or limitations.

Results: We identified and assessed 17 eligible systematic reviews. We assessed all 23 primary studies from the most recent systematic review with a broad intervention focus. All systematic reviews and primary studies described the population by one or more PROGRESS-Plus factor, most commonly across place of residence and age, respectively. None of the reviews and five primary studies examined differential effects across one or more PROGRESS-Plus dimension. Nine reviews and four primary studies discussed applicability or limitations of their findings by at least one PROGRESS-Plus factor.

Conclusions: Although we know that social isolation and loneliness are worse for the poorest and most socially disadvantaged older adults, the existing evidence base lacks details on how to tailor interventions for these socially disadvantaged older people.

Keywords: Equity; Intervention; Loneliness; Older adults; Overview of reviews; PROGRESS-plus; Social isolation; Systematic review.

Fig. 1

PRISMA flow chart of the selection process. In total, 2803 records were identified through searching and combining results from all databases: MEDLINE, EMBASE, CINAHL, PsycINFO, and SCOPUS. After removal of duplicates, 1647 records were screened at title and abstract level. Of these 1647 records, 22 articles were assessed at full text for eligibility. Five articles were excluded of which four had a wrong study design and one was not in English. Hence, 17 systematic reviews were included in our study for assessment

Fig. 2

Results of the description and analysis of health equity in systematic reviews (n = 17). Number of reviews reporting population characteristics, differential effects analysis, and applicability or limitations across PROGRESS-Plus items. Bars do not sum to 17 because reviews were double counted if they reported multiple types of relevant data across multiple PROGRESS-Plus item

Fig. 3

Results of the description and analysis of health equity in primary studies (n = 23). Number of primary studies reporting population characteristics, differential effects analysis, and applicability or limitations across PROGRESS-Plus items. Bars do not sum to 23 because studies were double counted if they reported multiple types of relevant data across multiple PROGRESS-Plus item