The influence of proximity to city parks and major roads on the development of arterial hypertension

Association of greenspaces exposure with cardiometabolic risk factors: a systematic review and meta-analysis

BACKGROUND

Cardiometabolic conditions are major contributors to the global burden of disease. An emerging body of evidence has associated access to and surrounding public open spaces (POS) and greenspace with cardiometabolic risk factors, including obesity, body mass index (BMI), hypertension (HTN), blood glucose (BG), and lipid profiles. This systematic review aimed to synthesize this evidence.

METHODS

This systematic review was conducted based on the PRISMA guidelines. Four electronic databases including Web of Science, PubMed, Scopus, and Google Scholar were searched for eligible articles published until July 2023. All observational studies which assessed the association of greenspace and POS with cardiometabolic risk factors including obesity, BMI, HTN, BG, and lipid profiles were included and reviewed by two authors independently. Heterogeneity between studies was assessed using the I2 index and Cochrane's Q test. Random/fixed effect meta-analyses were used to combine the association between greenspace exposure with cardiometabolic risk factors.

RESULTS

Overall, 118 relevant articles were included in our review. The majority of the articles were conducted in North America or Europe. In qualitative synthesis, access or proximity to greenspaces or POS impacts BMI and blood pressure or HTN, BG, and lipid profiles via various mechanisms. According to the random effect meta-analysis, more access to greenspace was significantly associated with lower odds of HTN (odds ratio (OR): 0.81, 95% confidence intervals (CIs): 0.61-0.99), obesity (OR: 0.83, 95% CIs: 0.77-0.90), and diabetes (OR:0.79, 95% CI: 0.67,0.90).

CONCLUSIONS

Findings of this systematic review and meta-analysis suggested that greenspace accessibility is associated with some cardiometabolic risk factors. Improving greenspace accessibility could be considered as one of the main strategies to reduce cardiometabolic risk factors at population level.

Associations of Urban Built Environment with Cardiovascular Risks and Mortality: a Systematic Review

With rapid urbanization, built environment has emerged as a set of modifiable factors of cardiovascular disease (CVD) risks. We conducted a systematic review to synthesize evidence on the associations of attributes of urban built environment (e.g. residential density, land use mix, greenness and walkability) with cardiovascular risk factors (e.g. hypertension and arterial stiffness) and major CVD events including mortality. A total of 63 studies, including 31 of cross-sectional design and 32 of longitudinal design conducted across 21 geographical locations and published between 2012 and 2023 were extracted for review. Overall, we report moderately consistent evidence of protective associations of greenness with cardiovascular risks and major CVD events (cross-sectional studies: 12 of 15 on hypertension/blood pressure (BP) and 2 of 3 on arterial stiffness; and longitudinal studies: 6 of 8 on hypertension/BP, 7 of 8 on CVD mortality, 3 of 3 on ischemic heart disease mortality and 5 of 8 studies on stroke hospitalization or mortality reporting significant inverse associations). Consistently, walkability was associated with lower risks of hypertension, arterial stiffness and major CVD events (cross-sectional studies: 11 of 12 on hypertension/BP and 1 of 1 on arterial stiffness; and longitudinal studies: 3 of 6 on hypertension/BP and 1 of 2 studies on CVD events being protective). Sixty-seven percent of the studies were rated as "probably high" risk of confounding bias because of inability to adjust for underlying comorbidities/family history of diseases in their statistical models. Forty-six percent and 14% of the studies were rated as "probably high" risk of bias for exposure and outcome measurements, respectively. Future studies with robust design will further help elucidate the linkages between urban built environment and cardiovascular health, thereby informing planning policies for creating healthy cities.

Association between greenspace and blood pressure: A systematic review and meta-analysis

Many studies have investigated the association between greenspaces and blood pressure (BP), but the results remain mixed. We conducted a systematic review and meta-analysis to comprehensively evaluate the evidence concerning greenspaces with BP levels and prevalent hypertension. Systematic literature searches were performed in Web of Science, PubMed, and Embase up to 25 April 2021. Combined effect estimates were calculated using random-effect models for each greenspace exposure assessment method that had been examined in ≥3 studies. Sensitivity analysis, subgroup analysis, and publication bias were also conducted. Of 38 articles (including 52 analyses, 5.2 million participants in total) examining the effects of normalized difference vegetation index (NDVI) (n = 23), proportion of greenspace (n = 11), distance to greenspace (n = 9), and others (n = 9) were identified. Most studies (65%) reported beneficial associations between greenspaces and BP levels/hypertension. Our results of meta-analyses showed that higher NDVI_500m was significantly associated with lower levels of systolic blood pressure (SBP = -0.77 mmHg, 95%CI: -1.23 to -0.32) and diastolic blood pressure (DBP = -0.32 mmHg, 95%CI: -0.57 to -0.07). We also found that NDVI in different buffers and the proportion of greenspaces were significantly associated with lower odds (1-9%) of hypertension. However, no significant effect was found for distance to greenspaces. In summary, our results indicate the beneficial effects of greenspace exposure on BP and hypertension. However, future better-designed studies, preferably longitudinal, are needed to confirm and better quantify the observed benefits in BP and/or hypertension.

Natural and built environments and blood pressure of Alpine schoolchildren

BACKGROUND

Early life environments may influence children's blood pressure (BP), but evidence on the combined effects of natural and built environment exposures is scarce. The present study investigates the associations of natural and built environment indicators, traffic noise, and air pollution with BP in children living in Alpine valleys.

METHODS

In 2004/2005, 1251 school children (8-12 years old) were sampled for a cross-sectional survey in several Austrian and Italian mountain valleys. Children's mothers completed a questionnaire. The outcomes of interest were systolic and diastolic BP measured with a calibrated oscillometric device. Indicators of land cover assigned to the residential and school coordinates within 100 and 1000 m included normalized difference vegetation index (NDVI), tree canopy cover, and a broader naturalness indicator titled distance to nature (D2N). The presence of a home garden was also measured via self-report. Imperviousness density served as a proxy for the built environment. Residential air pollution (NO₂) and noise (L_den) from traffic were calculated using bespoke modeling. NO₂, L_den, physical activity, and body mass index (BMI) were treated as mediating pathways.

RESULTS

Higher NDVI and tree cover levels in residential and school surroundings and home gardens were consistently associated with lower BP. The built environment was associated with higher BP. Counterintuitive inverse associations between NO₂ and L_den and BP were also found. Structural equation modeling showed that higher levels of greenspace and presence of a home garden were weakly associated with more outdoor play spaces, and in turn with lower BMI, and ultimately with lower BP.

CONCLUSIONS

Exposure to natural environments may help maintain normal BP in children, while built environment may increase children's BP. Outdoor play and less adiposity in greener areas may mediate some of these associations. Evidence on air pollution and noise remains controversial and difficult to explain.

Investigating the effects of occupational and environmental noise on cardiovascular diseases: a systematic review and meta-analysis

The present study aimed to use a meta-analysis to investigate the relationship between occupational and non-occupational noise exposure expressed in various studies with cardiovascular disease. This is a systematic review and meta-analysis study based on PRISMA checklist. In this study, the researchers searched five international databases of Medline/PubMed, Embase, Scopus, ISI/web of knowledge, and Google Scholar. Search keywords included two categories noise and noise pollution, cardiovascular disease, and hypertension. The Joanna Briggs Institute checklist was used to review and control the quality of the articles. After all screening stage 139 articles entered the final analysis. The results show that except for East African environmental studies and workplace studies in East Asia, Western Asia, and Northern Europe, there was a significant association between noise exposure and cardiovascular disease. Also, there was a significant difference between the intensity of sound and blood pressure in workers (OR = 1.28, CI 95%: 1.15-1.42, P < 0.001). Based on the results of environmental noise, there was a significant difference between ambient noise intensity and blood pressure (OR = 1.55, CI 95%: 1.53-1.57, P < 0.001). It can be concluded that it is very important to study and identify jobs or living environments with less than the recommended noise level and in addition to hearing aids that occur in over-standard exposures, such as cardiovascular disease.

Green Spaces, Land Cover, Street Trees and Hypertension in the Megacity of São Paulo

Proximity to green spaces has been shown to be beneficial to several cardiovascular outcomes in urban spaces. Few studies, however, have analyzed the relationship between these outcomes and green space or land cover uses in low-medium income megacities, where the consequences of rapid and inordinate urbanization impose several health hazards. This study used a subgroup of the dataset from The Brazilian Longitudinal Study of Adult Health ELSA-BRASIL (n= 3418) to identify the correlation between the medical diagnosis of hypertension and green spaces in the megacity of São Paulo. Land cover classification was performed based on the random forest algorithm using geometrically corrected aerial photography (orthophoto). Three different indicators of exposure to green spaces were used: number of street trees, land cover and number of parks within 1 km. We used logistic regression models to obtain the association of the metrics exposure and health outcomes. The number of street trees in the regional governments (OR = 0.937 and number of parks within 1 km (OR = 0.876) were inversely associated with a diagnosis of hypertension. Sixty-three percent of the population had no parks within 1 km of their residence. Our data indicate the need to encourage large-scale street tree planting and increase the number of qualified parks in megacities.