Sometimes more is more.
Correlations between socializing and survival were detected regardless of baseline health status, suggesting that physicians should be recommending daily socialization for all elderly patients, lead author Ziqiong Wang, MD, of Sichuan University West China Hospital, Chengdu, China, and colleagues reported.
These findings align with an array of prior studies reporting physical and mental health benefits from socialization, and negative impacts from isolation, the investigators wrote in the Journal of Epidemiology & Community Health. Not all studies have yielded the same picture, however, and most research has been conducted in Western countries, leading to uncertainty about whether different outcomes would be seen in populations in other parts of the world. Furthermore, the authors added that few studies have explored the amount of socialization needed to derive a positive benefit.
To address this knowledge gap, the investigators analyzed survival data from 28,563 participants in the Chinese Longitudinal Healthy Longevity Survey with a median age of 89 years at baseline.
Columbia University
Dr. John W. Rowe
“[This analysis] is from a highly respected ongoing longitudinal study of aging in China, which includes a large number of subjects and employs very strong research design and statistical analytical methods, so it has credibility,” John W. Rowe, MD, Julius B. Richmond Professor of Health Policy and Aging at Columbia University, New York, said in a written comment.
The investigators stratified frequency of socialization into five tiers: never, not monthly but sometimes, not weekly but at least once per month, not daily but at least once per week, and almost every day.
Survival proportions were calculated using the Kaplan-Meier method after accounting for a range of individual characteristics, including age, sex, household income, smoking status, diabetes, self-rated health, and others. Comparative findings were described in terms of time ratios using multivariable parametric accelerated failure time (AFT) models.
“The AFT model estimates the time ratio (TR), which is interpreted as the expected time to events in one category relative to the reference group,” the investigators wrote. “Unlike the interpretation of proportional hazard model results where hazard ratios larger than 1 are equal to higher risk, a TR of greater than 1 is considered to have a longer time to events, compared with the reference group.”
From baseline to 5 years, each socialization tier was significantly associated with prolonged survival, suggesting a general benefit. Compared with no socialization, socializing sometimes but not monthly was associated with 42% longer survival, at least monthly socialization was associated with 48% longer survival, at least weekly was associated with 110% longer survival, and socializing almost every day was associated with 87% longer survival.
The outsized benefit of daily socialization became clear in a long-term survival analysis, which spanned 5 years through the end of follow-up. Compared with no socialization, daily socialization tripled survival (TR, 3.04; P < .001), compared with prolongations ranging from 5% to 64% for less socialization, with just one of these lower tiers achieving statistical significance (P = .046).
Of note, the benefit of daily socialization was detected regardless of a person’s health status at baseline.
“No matter if elderly participants had chronic diseases or not, [and] no matter if older people had good self-rated health or not, the survival benefits of frequently participating in social activity were the same,” said principal author Sen He, MD, of Sichuan University, in a written comment.
“Socializing almost every day seems to be the most beneficial for a long life,” Dr. Sen added, noting that more research is needed to determine if there is an optimal type of social activity.
Dr. Rowe pointed out two key findings from the study. The first was that it confirmed “prior studies that have identified a beneficial effect of social activity on life expectancy.
“We have known that engagement is essential for successful aging and that isolation is toxic. While this finding is not novel, it is nice to see this confirmation of what we thought we knew,” he wrote.
Secondly, the study has identified “a threshold effect”, which is that “the long-term benefit on life expectancy was only seen in the presence of fairly intense social interactions, essentially daily,” he said.
University of Michigan
Dr. Preeti Malani
According to Preeti Malani, MD, professor of medicine and geriatrician at the University of Michigan, Ann Arbor, the findings are also helpful because they offer data from another part of the world, adding confidence in findings from Western countries.
“This [study] happens to focus on older adults in China, which is helpful since aging is not the same everywhere in the world,” Dr. Malani said. “While the numbers here may not be precise, it’s fair to say that socialization is good for your health – for everyone but especially for older adults.”
Considering the body of evidence now spanning a range of populations, Dr. Malani said physicians should be screening for, and recommending, socialization for all elderly patients, particularly because many aren’t getting enough of it.
“Work that my colleagues and I have done (with the National Poll on Healthy Aging) suggests that there is a portion of older adults that have very little to no social contact,” Dr. Malani said. “A physician may not know this unless they are asking routinely about socialization the way we might ask about diet and exercise. How much is enough? No one knows, but anything is better than nothing and likely more is better.”
She also suggested that personalization is key.
“Physical and emotional health may limit the ability to socialize, so not everyone can engage all the time,” Dr. Malani said. “Also, socialization can look different for different people. Technology allows for socialization even if an individual has trouble leaving their home. I especially worry about this issue for older adults that are also caregivers. Those individuals also need time for themselves” and on way to fulfill that need is by socializing with others.
The study was supported by Sichuan (China) Science and Technology Program, the National Key R&D Program of China, and the National Natural Science Foundation of China. The investigators, Dr. Rowe, and Dr. Malani disclosed no relevant conflicts of interest.