Comparison of Food Insecurity Classifications and Associations with Premature Cardiovascular Disease Mortality among US Adults

Background: Food security is usually measured with the 10-item US Adult Food Security Survey Module (FSSM). Shorter 6- or 2-item tools may capture similar information, but this has not been validated with hard endpoints. Hypothesis: We hypothesize a 2-item food security instrument reflects the same premature mortality risk as 10- and 6-item instruments. Methods: We included 37,027 participants aged 20-74 years from the National Health and Nutrition Examination Survey (NHANES) 2004-2018, linked to the National Death Index with follow-up through 2019. Cardiovascular disease (CVD) mortality was ascertained by ICD-10 codes for heart disease or stroke. Food security was assessed by the 10-item FSSM, which can derive 6- and 2-item instruments. Multivariable Cox regression was used to assess the associations of food insecurity classifications with risks of premature all-cause and CVD mortality. We calculated C-statistics to estimate model discrimination. We repeated the analyses among 218,136 participants from the National Health Interview Survey (NHIS) 2011-2018. Results: During a mean 7.8-year follow-up, 2025 premature deaths (512 from CVD) were recorded in NHANES. In age-sex-race/ethnicity-adjusted models (Model 1), food insecurity with any classification was strongly associated with premature all-cause and CVD mortality (Table). After adjusting for confounders (Model 2), associations were attenuated but remained statistically significant. After further including potential mediators (Model 3), associations diminished, suggesting pathways by which food insecurity is associated with mortality. Hazard ratios and C-statistics were nearly identical comparing 10-, 6-, and 2-item instruments. Results were equivalent among NHIS participants during a mean 5.0-year follow-up including 7025 premature deaths (1711 from CVD). Conclusions: Among two independent samples of US adults, a 2-item food security instrument is equivalently associated with premature mortality compared with 10- and 6-item instruments.