A study published by Heart found that loneliness and social isolation are linked to a 30 percent increased risk of having a stroke or developing coronary artery disease (CHD), the two leading causes of death for men and women.
“The aim of this study was to investigate the size of the association between deficiencies in social relationships and incident CHD or stroke, the two greatest causes of burden of disease in high income countries," wrote Nicole K. Valtorta, PhD student at the University of York in the U.K., and colleagues. “We conducted a systematic review to answer the following primary question: are deficiencies in social relationships associated with developing CHD and stroke in high-income countries?”
While loneliness has already been linked to a weakened immune system, high blood pressure and premature death, it is not clear what effect it would have on the rate of health disease and stroke.
Analyzing 16 research databases for relevant studies, published up to May 2015, researchers found 23 that were eligible. Of those that met inclusion criteria, which involved more than 181,000 adults, the data included 4,628 CHD 'events' (heart attacks, angina attacks, death) and 3,002 strokes recorded during monitoring periods ranging from three to 21 years.
Results yielded that loneliness/social isolation was associated with a 29 percent increased risk of a CHD and a 32 percent increased risk of having a stroke.
“We found an association between poor social relationships and incident CVD comparable in size to other recognized psychosocial risk factors, such as anxiety and job strain,” wrote Valtorta and coleagues. “Our findings indicate that efforts to reduce the risk of CHD and stroke could benefit from taking both loneliness and social isolation into account, as we found no evidence to suggest that one was more strongly related to disease incidence than the other.”
They concluded with, "similar to how cardiologists and other healthcare professionals have taken strong public stances regarding other factors exacerbating [cardiovascular disease], e.g. smoking, and diets high in saturated fats, further attention to social connections is needed in research and public health surveillance, prevention and intervention efforts.”