Loneliness among middle-aged men increases the risk of cancer and being single at the time of diagnosis confers a worse prognosis, suggest results from a Finnish longitudinal study with a mean follow-up of 20 years.
The study also found that while loneliness was associated with an increased risk of cancer, social isolation was not.
It is unclear why loneliness had a stronger association with cancer compared to social isolation, but it could be related to satisfaction, commented lead author Siiri-Liisi Kraav, a doctoral student at the University of Finland Oriental, Kuopio.
“For many people, their level of social contact (social isolation) is satisfactory and does not necessarily cause suffering. Loneliness, by definition, includes dissatisfaction with the situation,” Kraav said. Medscape Medical News.
The mechanisms underlying the association are unclear, but one possibility is inflammation. “It has been proposed that loneliness may disrupt the functions of the hypothalamic-pituitary-adrenal axis (HPA axis) and increase low-grade inflammation directly, through an unhealthy lifestyle or depressionshe explained.
The findings are a call to action, Kraav suggested. “Loneliness has many adverse health effects; increasing the incidence of cancer is just one of them. Therefore, it would be important to prevent these negative effects by developing effective interventions for loneliness and routinely examining loneliness. “
The study was published to the May issue of Research in psychiatry.
“There is an extensive literature linking both social isolation and loneliness to mortality from all causes and cardiovascular outcomes, but less specific to cancer,” said Dr. Julianne Holt-Lunstad, who did not participate in the study. ‘study.
“Also, many studies only look at isolation or loneliness, but there are fewer studies that include them among the same sample,” he said. “Therefore, this helps us better understand how the experience of social isolation and loneliness influences both the incidence and mortality rates associated with cancer.”
Holt-Lunstad, a professor of psychology and neuroscience at Brigham Young University in Provo, Utah, has published extensively on the impact of loneliness on health and, more recently, on loneliness and COVID-19 (World psychiatry. 2021; 20: 55-56).
The health impact of the loneliness and social isolation caused by the pandemic for “years or decades,” may not be fully understood, Holt-Lunstad said. Medscape Medical News. “While I hope that most people will be resilient or recover, I suspect that at least one subset of the population will have chronic effects. Therefore, we must continue to study this issue and prioritize it in public health.”
Details of the study
The Finnish study included 2570 men, aged 42 to 61, who participated in the study of the ischemic risk factor for Kuopio heart disease (KIHD).
Reference variables related to lifestyle, socioeconomic status, depression, and physical health along with loneliness and social isolation were assessed.
An 11-item loneliness scale was used to measure subjective satisfaction with social life, feelings of loneliness, and perceived discrepancy between desired and actual social contacts. Social isolation was measured using a different 10-item scale that measured “the number and frequency of different social contacts a person has,” Kraav explained.
During a mean follow-up of 20.4 years, 649 men (25.3%) developed cancer (proportion of risk [HR], 1.10; Pg = 0.028) and 283 died from the disease. The mean age of cancer diagnosis was 70 years and the most common cancers were prostate (n = 236, 9.2%), lung (n = 87, 3.4%), and colorectal (n = 79, 3). , 1%).
Participants who were diagnosed with cancer “were older than their healthy counterparts, drank more alcohol, and were smokers more often,” the authors noted.
However, multivariate analysis showed that loneliness was associated with the total incidence of cancer even after adjusting to a long list of covariates, including age, socioeconomic status, consumption of cancer. alcohol, smoking, physical activity, diet, sleep, depression, high-sensitivity C-reactive protein, systolic blood pressure, cholesterol, body mass index and a history of cardiovascular disease.
The association of social isolation with cancer incidence was lost after adjusting for lifestyle variables.
The study also found that among men who were diagnosed with cancer, those who were single, divorced or widowed at first died earlier than those who were married or living with a partner, at an average of 21, 5 years versus 23.4 years from baseline (Pg = .003).
However, the authors acknowledged that the limitation of the study was that loneliness, social isolation, and relationship status were only measured once, at baseline. “It is possible that for some of the participants there were numerous changes in their living conditions and relationships during the follow-up period, and having information about these changes would have improved the discussion about possible explanatory mechanisms,” the authors state.
Siiri-Liisi Kraav received the scholarship support from the National Education Agency of Finland. Kraav and Holt-Lunstad have not reported any conflicts of interest.
Psychiatry Res. 2021; 299: 113868. Full text