Socioeconomic disparities in asthma: a review of the literature

Published: October 17, 2021

Asthma is a relatively common respiratory condition affecting an estimated 3.6% of the global population. As a disease asthma does not discriminate in terms of whom it affects, with people from various countries, races and age groups affected. In contrast however the healthcare related outcomes of asthma do not appear to be evenly distributed and have been shown to vary by socioeconomic status (SES), with deprived communities known to suffer increased morbidity.

In a recent systematic review and meta-analysis published in The Journal of Allergy and Clinical Immunology (JACI), Redmond et al. bring together the existing literature in this area to provide an overview of the impact of SES on asthma healthcare utilization, exacerbations and mortality across a variety of populations. Literature searches were conducted in Embase, Medline and Web of Science, with all studies reporting differences by SES in primary care attendance, exacerbations, emergency department attendance, hospitalization, ventilation / intubation, readmission and asthma mortality identified. Analysis was conducted independently for each of the healthcare outcomes, along with subgroup analysis to explore differences within groups, for example the comparison of universally funded healthcare systems against those who are insurance-based.

Redmond et al. identified 61 studies, encompassing 1,145,704 patients, with the majority of studies reporting results from the United States (66%). Lower SES was associated with increased ED attendance (OR: 1.61; 95% CI: 1.40-1.84), hospitalization (OR: 1.63; 95% CI 1.34-1.99), readmission (OR: 1.31; 95% CI 1.19-1.44) and ventilation / intubation (OR: 1.76; 95% CI: 1.13-2.73), however no association with primary care attendances were identified (OR: 0.79; 95% CI: 0.51-1.24). Evidence of borderline significance was noted for increased exacerbations (OR: 1.18; 95% CI: 0.98-1.42) and mortality (OR: 1.12; 95% CI: 0.92-1.37). Of note, there was no compelling evidence that SES disparities were elevated in countries with an insurance-based healthcare system when compared to those with a universal government funded system. The odds of an ED attendance within insurance-based systems were 1.63 (95% CI: 1.40-1.90) for those of lower socioeconomic status, while in universal government funded systems the odds ratio was 1.56 (95% CI: 1.03-2.39).

In conclusion, Redmond et al. note that patients with a lower socioeconomic status have substantially increased secondary healthcare utilization, with evidence suggestive of increased exacerbations and mortality risk. These disparities were found to be consistently reported worldwide, including within countries offering universally funded healthcare systems.

The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.

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