Adults older than 50 years who report experiencing persistently high levels of loneliness have a 56% increased risk for stroke, a new study showed.
The increased stroke risk did not apply to individuals who reported experiencing situational loneliness, a finding that investigators believe bolsters the hypothesis that chronic loneliness is driving the association.
“Our findings suggest that individuals who experience chronic loneliness are at higher risk for incident stroke,” lead investigator Yenee Soh, ScD, research associate of social and behavioral sciences in the Harvard T.H. Chan School of Public Health, Boston, told this news organization. “It is important to routinely assess loneliness, as the consequences may be worse if unidentified and/or ignored.”
The findings were published online in eClinicalMedicine.
Significant, Chronic Health Consequences
Exacerbated by the COVID-19 pandemic, loneliness is at an all-time high. A 2023 Surgeon General’s report highlighted the fact that loneliness and social isolation are linked to significant and chronic health consequences.
Previous research has linked loneliness to cardiovascular disease, yet few studies have examined the association between loneliness and stroke risk. The current study is one of the first to examine the association between changes in loneliness and stroke risk over time.
Using data from the 2006-2018 Health and Retirement Study, researchers assessed the link between loneliness and incident stroke over time. Between 2006 and 2008, 12,161 study participants, who were all older than 50 years with no history of stroke, responded to questions from the Revised UCLA Loneliness Scale. From these responses, researchers created summary loneliness scores.
Four years later, from 2010 to 2012, the 8936 remaining study participants responded to the same 20 questions again. Based on loneliness scores across the two time points, participants were divided into four groups:
- Consistently low (those who scored low on the loneliness scale at both baseline and follow-up).
- Remitting (those who scored high at baseline and low at follow-up).
- Recent onset (those who scored low at baseline and high at follow-up).
- Consistently high (those who scored high at both baseline and follow-up).
Incident stroke was determined by participant report and medical record data.
Among participants whose loneliness was measured at baseline only, 1237 strokes occurred during the 2006-2018 follow-up period. Among those who provided two loneliness assessments over time, 601 strokes occurred during the follow-up period.
Even after adjusting for social isolation, depressive symptoms, physical activity, body mass index, and other health conditions, investigators found that participants who reported being lonely at baseline only had a 25% increased stroke risk, compared with those who did not report being lonely at baseline (hazard ratio [HR], 1.25; 95% confidence interval (CI), 1.06-1.47).
Participants who reported having consistently high loneliness across both time points had a 56% increased risk for incident stroke vs those who did not report loneliness at both time points after adjusting for social isolation and depression (HR, 1.56; 95% CI, 1.11-2.18).
The researchers did not investigate any of the underlying issues that may contribute to the association between loneliness and stroke risk, but speculated there may be physiological factors at play. These could include inflammation caused by increased hypothalamic pituitary-adrenocortical activity, behavioral factors such as poor medication adherence, smoking and/or alcohol use, and psychosocial issues.
Those who experience chronic loneliness may represent individuals that are unable to develop or maintain satisfying social relationships, which may result in longer-term interpersonal difficulties, Dr. Soh noted.
“Since loneliness is a highly subjective experience, seeking help to address and intervene to address a patient’s specific personal needs is important. It’s important to distinguish loneliness from social isolation,” said Dr. Soh.
She added that “by screening for loneliness and providing care or referring patients to relevant behavioral healthcare providers, clinicians can play a crucial role in addressing loneliness and its associated health risks early on to help reduce the population burden of loneliness.”