A Systematic Review of Financial Toxicity Among Cancer Survivors: We Can't Pay the Co-Pay.

Objective: To determine the extent of financial toxicity (FT) among cancer survivors, identify the determinants and how FT is measured.

Methods: A systematic review was performed in MEDLINE, CINAHL and PsycINFO, using relevant terminology and included articles published from 1 January, 2013 to 30 June, 2016. We included observational studies where the primary outcomes included FT and study samples were greater than 200. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed.

Results: From 417 citations, a total of 25 studies were included in this review. Seventy outcomes of FT were reported with 47 covering monetary, objective and subjective indicators of FT. A total of 28-48% of patients reported FT using monetary measures and 16-73% using subjective measures. The most commonly reported factors associated with FT were: being female, younger age, low income at baseline, adjuvant therapies and more recent diagnosis. Relative to non-cancer comparison groups, cancer survivors experienced significantly higher FT. Most studies were cross-sectional and causal inferences between FT and determinants were not possible. Measures of FT were varied and most were not validated, while monetary values of out-of-pocket expenses included different cost components across studies.

Conclusions: A substantial proportion of cancer survivors experience financial hardship irrespective of how it is measured. Using standardised outcomes and longitudinal designs to measure FT would improve determination of the extent of FT. Further research is recommended on reduced work participation and income losses occurring concurrently with FT and on the impacts on treatment non-adherence.