Urban green space can prevent premature deaths

Summary: A meta-analysis of nine longitudinal studies reveals urban green spaces are significantly associated with a reduction in premature mortality. A 4% reduction in premature mortality was linked to each increment of 0.1 in vegetation score within 500 meters of residential buildings.

Source: ISGLOBAL

Residential greenness can protect against premature all-cause mortality, according to a systematic review and meta-analysis conducted by the Barcelona Institute for Global Health (ISGlobal), an institution supported by “la Caixa”, in collaboration with Colorado State University and the World Health Organization (WHO), and published in The Lancet Planetary Health.

The analysis, which included nine longitudinal studies involving seven countries and a total of over eight million people, provides strong evidence on the impact of increasing green areas on mortality.

Half of the world’s population lives in cities, where there is often a lack of green space. Many studies suggests that green spaces in cities have a positive health effect, including less stress, improved mental health, and lower risk of cardiovascular disease, metabolic syndrome and premature death, among others. However, many of these studies look at only one specific point in time and use different ways to measure exposure to greenness.

This is why the research team decided to summarize the available evidence and focus on studies that were longitudinal -studies that follow the same cohort of individuals during several years-, used a simple measure of exposure to green space -the NDVI (Normalised Difference Vegetation Index) based on satellite images-; and looked at premature all-cause mortality as a health outcome. They identified nine cohort studies worldwide that included over eight million individuals in total, from seven different countries (Canada, United States, Spain, Italy, Australia, Switzerland and China).

The meta-analysis of these studies found that an increment in greenness around homes is significantly associated with reduced premature mortality. More specifically, the study provides an estimate for the protective effect: a 4% reduction in premature mortality per each increment of 0.1 in vegetation score, within 500 meters of the residence.

“This is the largest and most comprehensive synthesis to date on green space and premature mortality”, says David Rojas, researcher at ISGlobal and Colorado State University and first author of the study, “and the results support interventions and policies to increase green spaces as a strategy to improve public health”. Furthermore, this study “provides important information that can already be used in future Health Impact Assessment (HIA) studies”, explains Rojas.

This shows people walking in a city park
The analysis, which included nine longitudinal studies involving seven countries and a total of over eight million people, provides strong evidence on the impact of increasing green areas on mortality. The image is in the public domain.

Indeed, Rojas and colleagues are currently applying the results of the above meta-analysis to estimate the number of premature deaths that could be prevented in cities around the world if the city achieved its ambitious goal of increasing green infrastructures.

“Urban greening programmes are not only key to promoting public health, but they also increase biodiversity and mitigate the impacts of climate change, making our cities more sustainable and livable” concludes Mark Nieuwenhuijsen, director of the Urban Planning, Environment and Health Initiative at ISGlobal.

About this neuroscience research article

Source:
ISGLOBAL
Media Contacts:
Marta Solano – ISGLOBAL
Image Source:
The image is in the public domain.

Original Research: Closed access
“Green spaces and mortality: a systematic review and meta-analysis of cohort studies”. Rojas-Rueda D, Nieuwenhuijsen M, Gascon M, Perez-Leon D, Mudu P.
The Lancet Planetary Health doi:10.1016/S2542-5196(19)30215-3.

Abstract

Green spaces and mortality: a systematic review and meta-analysis of cohort studies

Background
Green spaces have been proposed to be a health determinant, improving health and wellbeing through different mechanisms. We aimed to systematically review the epidemiological evidence from longitudinal studies that have investigated green spaces and their association with all-cause mortality. We aimed to evaluate this evidence with a meta-analysis, to determine exposure-response functions for future quantitative health impact assessments.

Methods
We did a systematic review and meta-analysis of cohort studies on green spaces and all-cause mortality. We searched for studies published and indexed in MEDLINE before Aug 20, 2019, which we complemented with an additional search of cited literature. We included studies if their design was longitudinal; the exposure of interest was measured green space; the endpoint of interest was all-cause mortality; they provided a risk estimate (ie, a hazard ratio [HR]) and the corresponding 95% CI for the association between green space exposure and all-cause mortality; and they used normalised difference vegetation index (NDVI) as their green space exposure definition. Two investigators (DR-R and DP-L) independently screened the full-text articles for inclusion. We used a random-effects model to obtain pooled HRs. This study is registered with PROSPERO, CRD42018090315.

Findings
We identified 9298 studies in MEDLINE and 13 studies that were reported in the literature but not indexed in MEDLINE, of which 9234 (99%) studies were excluded after screening the titles and abstracts and 68 (88%) of 77 remaining studies were excluded after assessment of the full texts. We included nine (12%) studies in our quantitative evaluation, which comprised 8 324 652 individuals from seven countries. Seven (78%) of the nine studies found a significant inverse relationship between an increase in surrounding greenness per 0·1 NDVI in a buffer zone of 500 m or less and the risk of all-cause mortality, but two studies found no association. The pooled HR for all-cause mortality per increment of 0·1 NDVI within a buffer of 500 m or less of a participant’s residence was 0·96 (95% CI 0·94–0·97; I2, 95%).

Interpretation
We found evidence of an inverse association between surrounding greenness and all-cause mortality. Interventions to increase and manage green spaces should therefore be considered as a strategic public health intervention.

Funding
World Health Organization.

Feel free to share this Neuroscience News.
Join our Newsletter
I agree to have my personal information transferred to AWeber for Neuroscience Newsletter ( more information )
Sign up to receive our recent neuroscience headlines and summaries sent to your email once a day, totally free.
We hate spam and only use your email to contact you about newsletters. You can cancel your subscription any time.
  1. Thanks GOD & Ryder Trauma Center / Jackson Memorial Hospital l I am grateful to be alive. I am Marcelo Vidal and use to work at Pistils & Petals on Miami Beach, FL. and had my second night time job working on Venetian Lady Yacht Charters doing fabulous weddings and private parties for the rich and famous unfortunately on 10/17/15 this high speeding driver did not stop on his red light and crushed me in my car until firefighters arrived with, ” Jaws of Life ” rescued me out by boarding me on a Black Hawk Helicopter owned by Jackson Hospital which airlifted me Ryder Trauma Center / Jackson Memorial Hospital were I laid in coma for 29 days and stayed hospitalized for 6 months recovering from a fractured leg and Traumatic Brain Injury, TBI.. What saved my life was wearing my seatbelts as I am going to be doing therapy for the rest of my life and so grateful to be alive. I was released home wheel chair bound and wearing pampers because I could not comprehend until Brain Injury Association of Florida and Spinal Cord Program authorized therapy at American Pro-Health Physical Rehabilitation Center and by the Grace of God and the excellent therapy within a given me by Rafael GarciaOrtiz within a year or so I can walk, talk, comprehend and use the restroom.as I am grateful to be alive. By this time I was cleared to do Aquatic Therapy by Kelly Gomez Messett at Jackson Health System Recreation Therapy Neuro Group and had an awesome time swimming in an Olympic Pool as I am grateful to be alive. As I continue seeking Adaptive Rowing Therapy at Miami Beach Rowing Club while looking up I would to enjoy the beautiful South Florida weather as a crack of smile appears on my face knowing how thankful and grateful I am to be alive. During all this time till present date I have sessions with my Neuropsychologist Dr.Susan Ireland from the five inch head scare I have across my head that gives me constant pounding headaches with hallucinations and I can not take any medications because it would intensify my hallucinations so Dr. Ireland tought me this breathing counting exercise a form of meditation that has taken all my symptoms away as I have been DRUG-FREE NO MEDS for more than a year now as I continue doing therapy at Jackson Rehabilitation Hosp. continue my sessions with Dr. Ireland and attend TBI EXPRESSIONS CAFE/Recreation Therapy Neuro Group hosted by Kelly Gomez Messett every last Wednesday of the month at Diagnostic Building at Jackson Memorial Hospital in Miami, FL.from 6:30pm-8 pm as I continue my daily therapies listening to tbi Music lovers and do LoveYourBrain YOGA- Meditation -BIKE/ELLIPTICAL/WALK as I am extremely grateful to be alive as I enjoy reading and listen to I CARE FOR YOUR BRAIN with Dr. Sullivan & Brain Chat because of GOD I am extremely grateful to be alive. I get great information by reading Neuroscience research as I am extremely grateful to be alive.

Comments are closed.