Cancer inequalities experienced by people with disability: a systematic review

Abstract

Background: People with disability experience worse cancer outcomes than people without disability. One potential pathway is through low screening participation leading to delayed cancer diagnosis and late disease presentation. Objective: To summarise and evaluate evidence quantifying disability-related inequalities in (1) cancer mortality, (2) fatality among cancer patients; and for cervical, breast, colorectal and lung cancers: (3) screening participation and (4) stage at diagnosis. Methods: We searched MEDLINE, Embase, PsycInfo and Scopus up to November 2023 for studies that quantified disability-related inequalities in the four outcomes. Studies were evaluated using the Risk Of Bias In Non-randomized Studies - of Exposures tool. Results: We found 73 eligible articles globally. People with disability had higher cancer mortality compared to those without. This inequality was most pronounced among people with intellectual disability. Evidence showed substantially higher fatality among cancer patients with disability compared to those without consistently across disability groups and cancer types. Screening uptake for breast, cervical and colorectal cancers was consistently lower for people with various disability types in multiple countries. Evidence regarding inequalities in stage at diagnosis for people with disability was limited and inconsistent. The main methodological challenges for future research are: complexity in defining disability, underestimation of inequalities due to over-adjustment of mediating factors, under-representation of people with severe disability in data, and reporting inequalities on relative scales only. Conclusions: Existing evidence reinforces the need for high-quality cancer inequality research for this population, and a multi-pronged, inclusive approach to prioritise people with disability in the whole cancer control pathway.