Loneliness may increase the risk of stroke by as much as 56%, according to research that experts say explains why the issue poses a major health threat worldwide.
The World Health Organization (WHO) has said loneliness is among the most significant global health concerns, affecting every facet of health, wellbeing and development. The US surgeon general has warned that its mortality effects are equivalent to smoking 15 cigarettes a day.
While previous research has linked loneliness to a higher risk of developing cardiovascular diseases, few have examined the impact on stroke risk specifically. The study, led by Harvard University, is the first of its kind to examine the association between loneliness changes and stroke risk over time.
Researchers found that adults aged 50 and above who experienced chronic loneliness had a 56% higher risk of stroke than those who consistently reported not being lonely.
Those who experienced situational loneliness but did not suffer long term did not have a higher risk of stroke, the study found, suggesting the impact of loneliness on stroke occurs over many years.
The lead author, Dr Yenee Soh, research associate at the Harvard TH Chan School of Public Health, said: “Loneliness is increasingly considered a major public health issue. Our findings further highlight why that is.
“Especially when experienced chronically, our study suggests loneliness may play an important role in stroke incidence, which is already one of the leading causes of long-term disability and mortality worldwide.”
The findings were published in eClinicalMedicine.
The study used data from 2006 to 2018 from the University of Michigan’s health and retirement study. More than 12,000 people aged 50 and above who had never had a stroke were asked questions about loneliness between 2006 and 2008.
Four years later, about 9,000 people who remained in the study responded to the same questions and researchers then grouped them depending on their answers across the two time points.
The groups were “consistently low” (those who scored low on the loneliness scale at both points); “remitting” (those who scored high at first and low at follow-up); “recent onset” (those who scored low at first and high at follow-up); and “consistently high” (those who scored high at both baseline and follow-up).
After controlling for factors such as social isolation and depressive symptoms, which are closely related to loneliness but distinct, researchers found people considered lonely at the start of the study had a 25% higher risk of stroke than those not considered lonely.
But among those who scored “consistently high” for loneliness at both time points, there was a 56% higher risk of stroke than those in the “consistently low” group.
“Repeat assessments of loneliness may help identify those who are chronically lonely and are therefore at a higher risk for stroke,” said Soh.
People should be offered help based on their loneliness – which relates to how people feel even if surrounded by others – and not social isolation, which is different, Soh added.
“If we fail to address their feelings of loneliness, on a micro and macro scale, there could be profound health consequences.”
