Table 2.

HRs of percent park cover, NDVI and percent blue space cover with CVD and RSD hospitalization in the full and urban cohort of U.S. Medicare fee-for-service beneficiaries aged ≥65 years living in the contiguous U.S. from 2000 through 2016 (n = 63,009,173).^{a, b}.

Exposure (IQR)	CVD hospitalization		RSD hospitalization
	Full cohort	Urban cohort	Full cohort	Urban cohort
	HR (95% CI)	HR (95% CI)	HR (95% CI)	HR (95% CI)
% Park cover (15.9)	0.997 (0.995, 1.000)	0.991 (0.987, 0.996)	0.995 (0.991, 0.999)	0.995 (0.989, 1.002)
NDVI (0.27)	0.965 (0.959, 0.971)	0.979 (0.970, 0.989)	0.987 (0.977, 0.997)	1.018 (1.004, 1.032)
% Blue space cover (3.2)	0.999 (0.998, 1.000)	1.001 (1.000, 1.002)	0.997 (0.995, 0.998)	1.001 (0.999, 1.002)

^aAssociations are expressed per IQR increase of the CVD hospitalization (full) cohort. Models included percent park cover, NDVI and percent blue space cover simultaneously. Models were adjusted for calendar year, region, U.S. census covariates, % ever smoked, summer temperature, summer specific humidity, summer total precipitation, an offset for total person-time and strata for all possible combinations of sex, race, Medicaid Eligibility, age at study entry (2-year categories), and follow-up year. Urban cohorts included all person years in zip codes with a population density of 1000+ persons/mile².

^bIn the full cohorts, we observed 18, 610, 833 first CVD hospital admissions in 401, 315, 016 person years, 9,741,992 first respiratory disease hospital admissions in 453, 244, 756 person years. In the urban cohorts, we observed 8,354,677 first CVD hospital admissions in 185, 252, 789 person years, 4,387,395 first respiratory disease hospital admissions in 208, 437, 165 person years.