Prescription medication nonadherence associated with food insecurity: a population-based cross-sectional study.

Background: Food insecurity, defined as inadequate access to food owing to financial constraints, has been associated with poor disease management. Because cost-related nonadherence to prescription drugs is a possible explanation for such association, we examined the link between food insecurity and cost-related medication nonadherence in Canada.

Methods: Drawing on data for adult respondents (age ≥ 18 yr) who participated in the Canadian Community Health Survey 2016 Rapid Response module on prescription medication use, we assessed the association between household food insecurity and cost-related nonadherence to prescription drugs in the previous 12 months. We further examined the self-perceived health consequences of cost-related nonadherence among nonadherents. We applied Poisson models with bootstrap weights adjusting for sociodemographic characteristics.

Results: Of the 11 172 respondents in our sample, 930 (8.3%) reported cost-related nonadherence. Food insecurity affected 10.5% (95% confidence interval [CI] 9.1% to 11.8%) of adherents and 47.9% (95% CI 38.1% to 57.7%) of nonadherents. After adjustment for confounders, moderate and severe food insecurity were associated with 3.83 (95% CI 2.44 to 6.03) and 5.05 (95% CI 3.27 to 7.81) times higher prevalence of cost-related nonadherence, respectively, relative to food security. Despite being associated with lower probability of cost-related nonadherence, having drug insurance did not change the relation between food insecurity and cost-related nonadherence (p > 0.1 for all interactions). Severe food insecurity was correlated with higher prevalence of health deterioration and greater use of health care services as perceived consequences of cost-related nonadherence (p < 0.01 for both).

Interpretation: Food-insecure adults in Canada have a higher likelihood of cost-related nonadherence to prescription medications than their food-secure counterparts, which may constitute a burden on their health and lead to greater use of health care services.