Objective

Methods

Results

Conclusions

Background: Experimental and observational evidence in the fields of psychology, epidemiology, and urban planning supports a protective association between residential greenspace and health. Population research, however, relies primarily on cross-sectional data, which cannot rule out the rival hypothesis of ‘residential selection,’ in which healthier or socioeconomically advantaged individuals, over time, move to neighborhoods with greater greenspace. Moreover, few studies assess heterogeneity in relations between greenspace and health by sociodemographic characteristics, including race/ethnicity. These limitations leave open the questions of whether and for whom residential greenspace matters. Objective: This program of research advances the literature by (i.) using unique, longitudinal datasets to test whether changes in residential greenspace, or ‘green mobility,’ precede perinatal health improvements, (ii.) examining whether health benefits differ by maternal race/ethnicity, and (iii.) assessing the extent of bias induced by residential selection, a key, and often overlooked, threat to validity in research on greenspace and health. Methods: I used a probabilistic record linkage algorithm to identify births to the same mother in California between 2005 and 2015 and defined green mobility as census tract-level changes in the Normalized Difference Vegetation Index (NDVI), derived from satellite images of the earth’s surface, between births. Chapter 2 leverages a sibling comparison design to examine whether green mobility precedes reductions in maternal obesity risk, adjusting for obesity status at baseline. Chapter 3 uses maternal fixed effects analyses to assess whether green mobility varies with higher birthweight and lower risk of preterm birth (PTB) among non-Hispanic (NH) white and NH Black mothers, controlling for unmeasured maternal confounders involved in residential selection. Chapter 4 explores socioeconomic and health characteristics associated with subsequent green mobility, and whether patterns of social and health selection differ for NH white and NH Black mothers. Results: Findings indicate that upward green mobility varies with reduced obesity risk (Chapter 2) and increased birthweight in NH Black but not NH white mothers (Chapter 3). Results of Chapter 4 suggest that residential selection does not heavily confound previously observed findings but indicate important differences in patterns of residential selection for NH white and NH Black mothers. Conclusions: Taken together, findings from this program of research suggest, consistent with prior theoretical, experimental, and cross-sectional work, that increases in residential greenspace precede improvements in maternal and perinatal health. NH Black mothers, in particular, appear to benefit from increases in neighborhood greenness. The role of greenspace appears less certain for NH white mothers, who may selectively move to greener neighborhoods based on factors that also correlate with better health. Urban greening projects that target NH Black communities — but avoid the paradoxical effects of ‘green gentrification’ — may reduce persistent disparities in perinatal health.

(1) To test whether public psychiatric bed reduction may increase suicide rates; (2) to investigate whether the supply of private hospital psychiatric beds—separately for not-for-profit and for-profit—can substitute for public bed reduction without increasing suicides; and (3) to examine whether the level of community mental health resources moderates the relationship between public bed reduction and suicide rates.

We examined state-level variation in suicide rates in relation to psychiatric beds and community mental health spending in the United States for the years 1982–1998. We categorize psychiatric beds separately for public, not-for-profit, and for-profit hospitals.

Reduced public psychiatric bed supply was found to increase suicide rates. We found no evidence that not-for-profit or for-profit bed supply compensates for public bed reductions. However, greater community mental health spending buffers the adverse effect of public bed reductions on suicide. We estimate that in 2008, an additional decline in public psychiatric hospital beds would raise suicide rates for almost all states.

Downsizing of public inpatient mental health services may increase suicide rates. Nevertheless, an increase in community mental health funding may be promising.

The literature implies a 'diminished entelechy' hypothesis in which birth cohorts subjected to relatively many or relatively virulent environmental insults early in life do not realize their otherwise expected lifespan. No direct test of this hypothesis appears in literature.

We test the hypothesis directly by measuring the association between mortality in the first 5 years and life expectancy at age 5 for male and female cohorts born in Sweden (1751-1912), Denmark (1835-1913), and England and Wales (1841-1912). The methods control for trends, seasonal cycles, and other forms of autocorrelation that could induce spurious associations.

Our results support the hypothesis in that life expectancy at age 5 fell below the values expected from history in cohorts in which child mortality before age 5 increased over its expected value. We find no evidence for culling effects in which a cohort remaining after suffering relatively many environmental insults may be smaller but hardier than expected.

These findings converge with individual-level studies and suggest that suffering relatively virulent or many environmental insults during childhood reduces the subsequent lifespan of birth cohorts.