
In a recent study published in JAMA Network Open, researchers examine the associations of social isolation and loneliness with the danger of mortality in individuals with obesity versus normal-weight individuals.
Study: Improvement of Social Isolation and Loneliness and Excess Mortality Risk in People With Obesity. Image Credit: KieferPix / Shutterstock.com
The connection between obesity, social isolation, and loneliness
Obesity leads to varied metabolic disorders starting from type 2 diabetes (T2D) and chronic inflammation to heart problems (CVD) and cancer. The prevalence of obesity is rising, with about 30% of individuals in high-income countries (HICs) considered obese.
Likewise, loneliness is becoming a world public health crisis. Alongside social isolation, loneliness is an important social determinant of health; nonetheless, these two aspects correlate in another way with mortality.
Social isolation reflects the scarcity of contact with others basically, while loneliness represents a way of detachment potentially linked to emotional states like depression. Thus, one can experience loneliness even when living with others.
Within the absence of support, these two aspects may exacerbate the health behaviors of individuals with obesity. For instance, obese people often experience greater levels of social isolation and loneliness than non-obese individuals.
Concerning the study
In the current study, researchers screened the UK Biobank to discover obese and non-obese individuals based on body mass index (BMI). BMI values over and under 30 reflected obese and non-obese individuals, respectively. The study cohort comprised obese individuals and an equal variety of non-obese individuals randomly matched based on age, gender, and assessment center.
The first outcomes were all-cause mortality and mortality from cancer and CVD based on International Statistical Classification of Diseases and Related Health Problems (ICD) codes C00-C97 and I00-I99. The study end date was the date of death or November 27, 2021, whichever got here first.
Social isolation and loneliness were defined based on self-reported questionnaires within the U.K. Biobank. The researchers also investigated whether the obesity-related excess mortality risk may very well be removed or weakened by improving social isolation and loneliness indices.
Data on several variables were collected from the U.K. Biobank including age, gender, race/ethnicity, educational status, smoking status, alcohol consumption, and glycated hemoglobin (HbA1c) levels. After that, study participants were classified based on their weekly physical activity levels of lower than or greater than 150 minutes.
Each participant’s metformin and glucocorticoid use, in addition to their self-reported history of depression, anxiety, eating disorders, hypertension, high cholesterol, and diabetes, were also recorded.
Fisher exact or Wilcoxon rank-sum tests were used to look at participant characteristics based on obesity status. Moreover, Cox regression models determined the association of social isolation and loneliness with all-cause, cancer- and CVD-related mortality in obese people.
One other statistical model helped the researchers determine the contribution of social isolation and loneliness to the relative risk in individuals with obesity against lifestyle-related risk aspects for mortality, including depression, anxiety, and the Townsend Deprivation Index amongst individuals with obesity. Two sensitivity analyses were also performed to make sure the steadiness of the outcomes.
Study findings
The study included 398,972 participants, 55.3% of whom were women, with a median age of 55.9 years. Of the study cohort, 93,357, or 23.4%, were obese, whereas 305,615, or 76.6%, were non-obese.
Among the many obese participants, 48.9%, 40.6%, and 10.5% had a social isolation index of zero, one, and over two, which reflected no, mild, and moderate-to-severe social isolation, respectively. Loneliness indices of zero, one, and two also applied to 63.6%, 28.5%, and seven.9% of obese participants, respectively.
As in comparison with controls, individuals with obesity had a markedly higher prevalence of social isolation and loneliness. Moreover, over a median follow-up of 12.7 years, 22,872 incident deaths, including 11,442, 4,372, and seven,058 cancer-, CVD-related and other deaths, respectively.
Of all mortality risk aspects, social isolation ranked fourth by way of strength, whereas loneliness was ranked fourteenth.
Conclusions
The present U.K. Biobank cohort study found that social isolation was more strongly related to mortality than loneliness. Thus, stopping social isolation and mitigating its effects could also be more useful for reducing the danger of all-cause and CVD-related mortalities than loneliness, lifestyle aspects, depression, and anxiety in individuals with obesity.
Importantly, more intensive interventions are needed to enhance social isolation in individuals with obesity than in people without obesity to lower the danger of mortality.
Journal reference:
- Zhou, J., Tang, R., Wang, X., et al. (2024). Improvement of Social Isolation and Loneliness and Excess Mortality Risk in People With Obesity. JAMA Network Open. doi:10.1001/jamanetworkopen.2023.52824