Loneliness is detrimental to heart as well as mind, studies reveal
USA: Loneliness may increase the risk of cardiovascular and cerebral diseases, according to two recent studies. The study, published in the journal Neurology showed that loneliness increases the 10-year risk of developing dementia. On the other hand, the second study, published in JAMA Network Open showed social isolation and loneliness to be associated with increased risk of incident cardiovascular disease (CVD) among older women in the US.
Increased Dementia risk
In the study, Joel Salinas, The Framingham Study, Boston, MA, and colleagues aimed to determine the association of loneliness with 10-year all-cause dementia risk and early cognitive and neuroanatomic imaging markers of Alzheimer's disease and related dementia (ADRD) vulnerability.
For this purpose, they conducted a retrospective analysis of prospectively collected data from the population-based Framingham Study cohorts (09/09/1948-12/31/2018). Eligible participants were dementia-free at baseline and had loneliness assessed. Loneliness was recorded using the Center for Epidemiologic Studies Depression Scale; defined conservatively as feeling lonely ≥3 days in the past week. Incident dementia over a 10-year period, cognition, and MRI brain volumes and white-matter injury were the main outcomes.
The findings of the study were as follows:
- Of 2308 participants (mean age, 73 years; 56% women) who met eligibility in the dementia sample, 14% (329/2308) developed dementia; 6% (144/2308) were lonely.
- Lonely (versus not lonely) adults had higher 10-year dementia risk (age-, sex-, and education-adjusted hazard ratio, 1.54).
- Lonely participants younger than age 80 without APOE ε4 alleles had a three-fold greater risk (adjusted hazard ratio, 3.03).
- Among 1875 persons without dementia who met eligibility in the cognition sample (mean age, 62 years; 54% women), loneliness was associated with poorer executive function, lower total cerebral volume, and greater white-matter injury.
"Over 10 years of close clinical dementia surveillance in this cohort study, loneliness was shown to be associated with increased dementia risk; this tripled in adults whose baseline risk would otherwise be relatively low based on age and genetic risk, representing a majority of the US population," wrote the authors.
"Also, loneliness was associated with worse neurocognitive markers of ADRD vulnerability, indicating an early pathogenic role. These findings may have important clinical and public health implications given observed loneliness trends."
"This study provides Class I evidence that loneliness increases the 10-year risk of developing dementia," they concluded.
Increased risk of cardiovascular disease
In the study, Natalie M. Golaszewski, University of California, San Diego, and colleagues aimed to examine the associations of social isolation and loneliness with incident CVD in a large cohort of postmenopausal women and whether social support moderated these associations in a prospective cohort study, conducted from March 2011 through March 2019.
The study included community-living US women aged 65 to 99 years from the Women's Health Initiative Extension Study II who had no history of myocardial infarction, stroke, or coronary heart disease. Using validated questionnaires, social isolation and loneliness were ascertained. Major CVD, which was physician adjudicated using medical records and included coronary heart disease, stroke, and death from CVD was the main outcome.
The findings of the study were as follows:
- Among 57 825 women (mean age, 79.0 years; 89.1% White), 1599 major CVD events occurred over 186 762 person-years.
- The HR for the association of high vs low social isolation scores with CVD was 1.18, and the HR for the association of high vs low loneliness scores with CVD was 1.14.
- The HRs after additional adjustment for health behaviors and health status were 1.08 for social isolation and 1.05 for loneliness.
- Women with both high social isolation and high loneliness scores had a 13.0% to 27.0% higher risk of incident CVD than did women with low social isolation and low loneliness scores.
- Social support was not a significant effect modifier of the associations (social isolation × social support: r, –0.18; P = .86; loneliness × social support: r, 0.78).
"The study showed that social isolation and loneliness are associated with increased risk of incident CVD among older women in the US, suggesting that interventions to reduce social isolation and loneliness in this population are warranted," concluded the authors.
References:
1) Association of Loneliness With 10-Year Dementia Risk and Early Markers of Vulnerability for Neurocognitive Decline Joel Salinas, Alexa S. Beiser, Jasmeet K. Samra, Adrienne O'Donnell, Charles S. DeCarli, Mitzi M. Gonzales, Hugo J. Aparicio, Sudha Seshadri Neurology Feb 2022, 10.1212/WNL.0000000000200039; DOI: 10.1212/WNL.0000000000200039
2) Golaszewski NM, LaCroix AZ, Godino JG, et al. Evaluation of Social Isolation, Loneliness, and Cardiovascular Disease Among Older Women in the US. JAMA Netw Open. 2022;5(2):e2146461. doi:10.1001/jamanetworkopen.2021.46461
KEYWORDS: JAMA, Neurology journal, loneliness, social isolation, cardiovascular disease, cerebrovascular disease, dementia, stroke, mortality, coronary heart disease, cvd, Alzheimer disease, Joel Salinas, Natalie M Golaszewski, covid 19 pandemic
