Current evidence suggests that the characteristics of an area in which a person lives can negatively affect their cardiovascular health. This includes, for example, the density of fast food outlets; levels of violence, noise, and pollution; drug use; and building disrepair.
But few studies have looked at the potential health enhancing effects of positive local neighbourhood characteristics, such as perceived neighbourhood social cohesion, say the authors.
They therefore tracked the cardiovascular health of over 5000 US adults with no known heart problems over a period of four years, starting in 2006. Their average age was 70, and almost two thirds were women and married (62%).
All the study participants were taking part in the Health and Retirement Study, a nationally representative study of American adults over the age of 50, who are surveyed every two years.
In 2006 participants were asked to score on a validated seven point scale how much they felt part of their local neighbourhood; if they felt they had neighbours who would help them if they got into difficulty; whether they trusted most people in the area; and felt they were friendly.
Potentially influential factors, such as age, race, gender, income, marital status, educational attainment, outlook and attitude, social integration, mental health, lifestyle, weight, and underlying health issues, such as diabetes and high blood pressure, were all taken into account.
During the four year monitoring period, 148 of the 5276 participants (66 women and 82 men) had a heart attack.
Analysis of the data showed that each standard deviation increase in perceived neighbourhood social cohesion was associated with a 22% reduced risk of a heart attack. Put another way, on the seven-point scale, each unit increase in neighbourhood social cohesion was associated with a 17% reduced risk of heart attack.*
This association held true even after adjusting for relevant sociodemographic, behavioural, biological, and psychosocial factors, as well as individual-level social support.
The researchers say their findings echo those of other studies which have found a link between well integrated local neighbourhoods and lower stroke and heart disease risk.
This is an observational study so no definitive conclusions can be drawn about cause and effect, and the researchers admit that some potentially important risk factors, such as family history of heart disease/stroke and genetic influences were not known. But a strong social support network of friends and family has been linked to better health, so friendly neighbourhoods might be an extension of that, they say.
"Perceived neighbourhood social cohesion could be a type of social support that is available in the neighbourhood social environment outside the realm of family and friends," they write.
And tight-knit local communities may help to reinforce and 'incentivise' certain types of cohesive behaviours and so exclude antisocial behaviours, they suggest.