A paper by Brady et al. (2023) aims to measure this relationship in the US. They use data from the 1997-2019 Panel Study of Income Dynamics (PSID) data merged with the Cross-National Equivalent File. The data were validated with information from the National Death Index. The authors adjust for self-reported health, demographics, comorbidities and a variety of other factors. They find that:
Current poverty is associated with a greater mortality hazard of 1.42 (95% CI, 1.26-1.60). Cumulative poverty—being always in poverty vs never in poverty in the past 10 years—is associated with a greater mortality hazard of 1.71 (95% CI, 1.45-2.02).
This is a significantly higher mortality risk factor compared to many common comorbidities.