Is green land cover associated with less health care spending? Promising findings from county-level Medicare spending in the continental United States

Green land covers (e.g., forests and parks) are associated with better human health. Better health, in turn, may lead to lower spending on healthcare, an increasingly large portion of the budget of both American citizens and the government. There is a significant gap in our knowledge on the direct association between green covers and health care costs. We estimated associations between the percentage of green land cover in a county and its age- and risk-adjusted Medicare fee-for-service expenditures for each of five types of green land cover (forest, shrub, grass, agriculture, and urban vegetation) drawn from the 2011 National Land Cover Database. Generalized linear mixed models were used to predict median regionally standardized per-capita Medicare expenditures for 2010–2014 for 3,086 counties (comprising over 30 million Medicare fee-for-service users), with state as a random effect and controls for environmental, behavioral, and healthcare access covariates. We found associations between two types of green land cover and healthcare spending. Forest and shrub covers were significantly and inversely associated with median Medicare fee-for-service spending with small effect sizes. Grass land cover did not have a statistically significant association with expenditures. For agriculture and urban vegetation land covers, the results were unclear. Counties with more forest and shrub land cover may hold both health and economic benefits for the elderly and disabled. This study demonstrates that exposure to green land cover may be linked to lower healthcare spending. However, more definitive studies, particularly those that use individual-level data, are needed.