Studies show that people tend to be happier and healthier when they are surrounded by strong social networks, while people who are lonely and isolated tend to have worse health outcomes.
But does the same paradigm hold true in prison, where social networks are more complex?
Now, a new study of incarcerated men from a medium-security prison in Pennsylvania finds that despite the possible risks associated with socializing in prison, people with strong social ties tend to be healthier, on average, than those who are isolated.
The research was co-authored by Derek Allen Kreager, Ph.D., professor of sociology and criminology at Pennsylvania State University, and published in the Journal of Health and Social Behavior.
Researchers drew on a sample of 132 prisoners from a "good behavior" unit and administered surveys about their health habits and their friendships in prison. They then traced relationships between the incarcerated people using a technique called an exponential random graph model.
The researchers created a map of the prisoners' social relationships, clustering those who are highly connected near the center of the map, while those with only one or two friendships landed on the periphery.
Overall, findings suggested that incarcerated people who shared the same race, religion, and exercise routines tended to become friends. And the stronger the friendships and the more socially connected a prisoner, the healthier he tended to be.
Researchers split the 132 men into eight groups, separated by their degree of "indegree," or social connections. The most socially connected prisoners (Group 4) were less likely to smoke and more likely to exercise every day and have more muscle mass than other prisoners.
Meanwhile, the least connected prisoners (Group 6) were almost universally smokers. About half reported daily exercise, but overall their composite health score was lower.
"I was not really surprised by these findings based on what I see in our clinical setting," said Melissa Badowski, Pharm.D., BCPS, AAHIVP, clinical associate professor at the University of Illinois in Chicago.
"It is very obvious that those who are socially isolated tend to have worse health outcomes, especially if an element such as segregation [solitary confinement] is involved," said Badowski, a pharmacist who treats prisoners in Illinois and was not involved in the study.
"It isn't only based on physical health, but mental health too," she added.
According to Kreager, the healthiest subgroup in this study was composed of black men who practiced Islam. These men tended to exercise every day and avoided smoking. Some of the men who hailed from particularly disadvantaged circumstances prior to their incarceration reported that their health actually improved in prison.
"They did not have very strong organization in their lives before going to prison. Islam became a way to create a community in prison where they can start to help themselves," Kreager said.
The study survey did not ask participants about their sexual orientation or gender identity -- factors that might contribute to isolation, Badowski noted.
"I would have liked to have seen some consideration given to sexual orientation," she said. "In many instances, these individuals seek out isolation or act out to gain segregation -- they feel more protected being alone than in the general population.
"In addition," Badowski continued, "people who identify as transgender also have a difficult time integrating into social networks in the prison setting, since they may identify as a woman but are housed in a male prison."
But it's not just LGBT prisoners. Advocates calling for an end to mass incarceration in the United States have long pointed out that, more and more, prisons have become a place that warehouses people who should be receiving mental health services. And even the World Health Organization has noted that incarceration itself increases mental health challenges in people who are or have been incarcerated. While there is debate about what a justice system should look like, many people across political perspectives are coming to consensus that other strategies are needed to address mental health and to reduce the footprint of prison systems overall.
While this study looked at overall health and wellness, it did not include questions about the prisoners' HIV, hepatitis C, or other infectious disease status. But many studies have shown that prisons themselves -- due to close quarters, a lack of health services, and unsanitary conditions -- can lead to outbreaks of major infectious diseases like tuberculosis and hepatitis C.
"We were concerned about people being reluctant to answer those questions," explained Kreager, who noted that further studies would be needed to see if social networks have a positive or negative impact on HIV, hepatitis C, and other transmission rates.
Badowski hypothesized that "in the world of HIV, [isolation] translates to reduced medication adherence and, ultimately, loss of virologic suppression." However, she noted that right now, "there is no data on this topic."
The findings of this study contrast with Kreager's prior research in the Netherlands, where he found that people incarcerated for short stints had better mental health outcomes when they avoided other prisoners.
He wondered how these dynamics would play out in the United States, where people are often incarcerated for years -- sometimes for life. Could it be better for incarcerated people to avoid each other? Or would it be healthier to form social bonds?
"We could see the strengths in both hypotheses," he said, but "we know so little about the way relationships in prisons hold up."
He and his colleagues hope that the social network mapping model can be replicated in other prison settings. And, as they discovered, prisoners in the Pennsylvania medium-security prison who socialize are likely to see health benefits.
"Here, we're talking about men who had been incarcerated much longer," said Kreager. "You can't stay as isolated for that long and be healthy."