Table 3.

Sensitivity analysis for associations between green spaces and cardiovascular incidence, readmission, and mortality in four population-based cohorts of urban residents in Ontario, Canada, 2000–2014.

Outcome	$+\mathrm{N}{\mathrm{O}}_{\mathrm{2}}$ and $\mathrm{P}{\mathrm{M}}_{\mathrm{2}\mathrm{.5}}$c	$+\mathrm{Comorbidities}$c	$+\mathrm{Proximity}$ to hospitalsc	$+\mathrm{Deprivation}$c	$+\mathrm{Active}$ commutingc	$+\mathrm{Average}$ property valuec	Restricted to those survivingc $>5\mathrm{y}$	Within a $500\text{-m}$ buffer
	HR (95% CI)	HR (95% CI)	HR (95% CI)	HR (95% CI)	HR (95% CI)	HR (95% CI)	HR (95% CI)	HR (95% CI)
Full cohorta
Mortality
CVD	0.89 (0.87, 0.91)	0.91 (0.89, 0.92)	0.90 (0.89, 0.92)	0.91 (0.89, 0.92)	0.89 (0.87, 0.91)	0.91 (0.89, 0.92)	0.91 (0.89, 0.93)	0.89 (0.87, 0.90)
NAC	0.90 (0.88, 0.91)	0.91 (0.90, 0.92)	0.90 (0.89, 0.91)	0.90 (0.89, 0.91)	0.90 (0.88, 0.91)	0.90 (0.89, 0.91)	0.91 (0.90, 0.92)	0.89 (0.88, 0.90)
Incidence cohorta
Mortality
CVD	0.89 (0.87, 0.91)	0.91 (0.90, 0.93)	0.90 (0.88, 0.92)	0.91 (0.89, 0.92)	0.89 (0.87, 0.91)	0.91 (0.89, 0.92)	0.91 (0.89, 0.93)	0.89 (0.88, 0.91)
NAC	0.90 (0.88, 0.91)	0.91 (0.90, 0.92)	0.90 (0.89, 0.91)	0.91 (0.89, 0.92)	0.90 (0.88, 0.91)	0.90 (0.89, 0.91)	0.91 (0.90, 0.92)	0.89 (0.88, 0.90)
Incidence
AMI	0.95 (0.92, 0.97)	0.94 (0.92, 0.96)	0.96 (0.94, 0.98)	0.93 (0.91, 0.95)	0.93 (0.91, 0.95)	0.93 (0.91, 0.96)	0.93 (0.91, 0.95)	0.91 (0.89, 0.93)
HF	0.95 (0.94, 0.97)	0.95 (0.93, 0.96)	0.95 (0.93, 0.96)	0.92 (0.91, 0.94)	0.94 (0.92, 0.95)	0.94 (0.93, 0.96)	0.94 (0.92, 0.95)	0.93 (0.92, 0.95)
AMI cohortb
Readmission (mortality)	1.03 (0.98, 1.07)	1.02 (0.98, 1.06)	1.02 (0.98, 1.06)	0.99 (0.94, 1.05)	1.03 (0.98, 1.07)	1.02 (0.98, 1.06)	1.03 (0.98, 1.08)	1.01 (0.96, 1.05)
CVD	0.99 (0.92, 1.05)	0.99 (0.93, 1.05)	0.99 (0.93, 1.05)	0.98 (0.91, 1.05)	0.99 (0.93, 1.05)	0.99 (0.94, 1.05)	0.96 (0.87, 1.04)	0.96 (0.90, 1.02)
NAC	0.99 (0.94, 1.03)	1.00 (0.96, 1.04)	1.00 (0.95, 1.04)	0.98 (0.93, 1.03)	0.99 (0.95, 1.04)	1.00 (0.95, 1.04)	0.98 (0.92, 1.04)	0.99 (0.94, 1.03)
HF cohortb
Readmission (mortality)	1.00 (0.95, 1.06)	0.99 (0.94, 1.04)	0.99 (0.95, 1.04)	0.99 (0.94, 1.04)	1.00 (0.95, 1.04)	0.99 (0.95, 1.03)	0.99 (0.92, 1.06)	0.99 (0.95, 1.04)
CVD	0.99 (0.94, 1.05)	0.98 (0.93, 1.03)	0.98 (0.93, 1.04)	1.01 (0.96, 1.06)	0.99 (0.94, 1.03)	0.99 (0.94, 1.03)	0.99 (0.90, 1.08)	0.98 (0.93, 1.03)
NAC	0.99 (0.95, 1.03)	0.99 (0.95, 1.03)	0.98 (0.94, 1.02)	0.99 (0.95, 1.03)	0.98 (0.95, 1.02)	0.99 (0.96, 1.03)	0.96 (0.90, 1.03)	0.99 (0.95, 1.03)

Note: Each covariate was added individually to the main analysis presented in Figure 1. AMI, acute myocardial infarction; CI, confidence interval; CVD, cardiovascular disease; HF, heart failure; HR, hazard ratio; IQR, interquartile range; NAC, nonaccidental.

^aTwo-level nested, spatial random-effects Cox proportional hazards model (level one: census division, level two: census tract). Hazard ratios were scaled to an interquartile increase in NDVI (full and incidence cohorts: $\text{IQR}=0.17$). The fully-adjusted model included age, sex, region (lived or not in the Greater Toronto Area), area-level unemployment, percent less than high school education, percent recent immigrants, and household income (quintiles), and population density. The number of events are: $n=\mathrm{114,208}$ (CVD death) and $n=\mathrm{330,560}$ (nonaccidental death) for full cohort; $n=\mathrm{88,263}$ (CVD death), $n=\mathrm{277,174}$ (nonaccidental death), $n=\mathrm{58,553}$ (AMI incidence), and $n=\mathrm{134,655}$ (HF incidence) for incidence cohort.

^bFor the AMI and HF cohorts, the models further adjusted for clinical severity, in-hospital care, medications at discharge, smoking, and individual-level SES variables (AMI cohort: $\text{IQR}=0.12$; HF cohort: $\text{IQR}=0.13$). The number of events are: $n=\mathrm{2,788}$ (CVD death), $n=\mathrm{5,463}$ (nonaccidental death), $n=\mathrm{4,419}$ (CVD readmission) for AMI cohort; $n=\mathrm{4,981}$ (CVD death), $n=\mathrm{9,151}$ (nonaccidental death), $n=\mathrm{5,482}$ (CVD readmission) for HF cohort.

^cWithin $250\mathrm{m}$ of study participants’ postal-code residences.