Images by: Mark Andrew Boyer

Candi Darley, now 52, was working as a nurse and living in Washington, D.C., with her new husband, when, she said, “something started happening to me.” She began to have chronic pain and allergic reactions to common chemicals.

“Something started bothering me mentally. I also became physically ill,” she told Healthline.

When her husband left her several years later, Darley’s problems snowballed. Her mental and physical illness, later diagnosed as depression, fibromyalgia, and chronic fatigue syndrome, led her to miss work. She was eventually fired from her job. With no job, she could no longer make her mortgage payments.

In 2003, she took her son to a relative’s house and went to a homeless shelter for what she thought would be a few months. She was homeless for seven years.

While homeless, Darley made repeated trips to the emergency room seeking help and a diagnosis for her symptoms.

“You don’t get the right kind of care,” she said. “It would be this look of condescension. Sometimes I didn’t go.”

Being homeless also made it nearly impossible for Darley to manage her own health.

"You don’t rest enough. In the shelter you have to be up by a certain time,” she said. “I’m allergic to a host of things. In your own home you can recognize and change these things, but when you’re in a shelter you have absolutely no say as to what goes on.”

Even though the shelter Darley stayed in was a pretty good one, the sick and the elderly were thrown together in a single room with no barriers to stop the spread of disease.

And then there was the constant threat of violence.

“In such close quarters and with the frustration factor being so high, people are bound to clash,” she said.

The English philosopher Thomas Hobbes imagined that in a world before civilization, human life was “poor, nasty, brutish, and short.” His 17th-century description is all too apt for the lives of the homeless people who have fallen through the cracks in the United States since the 1980s.

Life for the half a million Americans who are homeless is short — they die, on average, before age 50 — and it is certainly brutish.

Skin infections, fungal outbreaks, and parasites are common. Bronchitis, pneumonia, and even tuberculosis spread in the close quarters of homeless shelters and squats. More than 5 percent of U.S. tuberculosis cases occur in homeless patients, according to the .

Homeless people also suffer from the same chronic illnesses that affect other Americans: diabetes, chronic obstructive pulmonary disease (COPD), asthma, high blood pressure, and HIV. It’s hard enough for people with regular routines and medical care to control these conditions. It’s a Herculean task for the homeless.

Chronic conditions kill homeless people as much as two decades earlier, according to Dr. Sharad Jain, the faculty advisor for a homeless health clinic offered by medical students at University of California, San Francisco.

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Trauma ‘Practically Universal’

A rare drizzle was falling outside San Francisco’s Tom Waddell Clinic, a public health clinic founded just after the devastation of the 1906 earthquake. The clinic has served the city’s substantial homeless population since 1986. 

Several men who looked to be in their mid-40s were taking shelter in the doorway. A younger woman was trying to sleep on the sidewalk with a Rottweiler mix cradled in her arms and a pit bull nuzzling against her legs.

The conditions for sleep were less than ideal. Across the street, deafening construction was underway on a high-rise sure to boast multi-million dollar condominiums.

Dr. Barry Zevin is the slouched, soft-spoken medical director of San Francisco’s Homeless Outreach Team, based at the Tom Waddell Clinic. For two decades, it’s been his job to build old-fashioned doctor-patient relationships with the people that most other San Franciscans try not to see. His goal: to get them free medical care in a healthcare system that conspires against it.

Clinics like Tom Waddell reach only one in three homeless people who need medical attention, according to the National Coalition for the Homeless.

It’s common for people to become homeless, like Candi Darley, in part because of health problems. Many are also dealing with the loss of a major relationship.

Doctors like Zevin who specialize in treating the homeless don’t deny that many are mentally ill and many have substance abuse problems. But those conditions affect a smaller share of homeless people than you might think. Less than 4 in 10 homeless people are dependent on alcohol and less than 3 in 10 abuse other drugs, according to 2003 data from the Substance Abuse and Mental Health Services Administration. Between 20 and 50 percent of the homeless have a serious mental illness, according to 2013 data.

The most widely shared problem among homeless people is not substance abuse or mental illness — it’s trauma, Zevin said.

“Violence and victimization are a daily reality to most homeless people I see,” Zevin said. “If I had to say one unifying theme of practically everyone I see it’s this idea of having been traumatized, whether that was in childhood at the hands of parents, whether that was in adolescence, or sexual trauma, whether that’s in the streets. It’s just practically universal.”

Image source: Mark Andrew Boyer

Trauma, in one Australian survey, affected 100 percent of homeless women and 90 percent of homeless men. Post-traumatic stress disorder is so pervasive among homeless people that some psychologists have posited that losing one’s home is itself a trauma that can trigger the condition.

Trauma may also have spurred Candi Darley’s mental and physical symptoms. It often causes depression, and has been to and fibromyalgia.

Violence is widespread in the streets and in shelters, as Darley recounted. Patients who are mentally ill are sometimes beaten for being disruptive. Patients who carry prescription drugs, even those with no street value, can be assaulted and robbed. In one , half of respondents said an experience of violence prolonged their homelessness.

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Bringing Routine to Chaotic Lives

It’s relatively easy for doctors to treat the infections and infestations that dog the homeless. The UCSF medical students travel to a long-term shelter and treat cuts, bruises, and infections.

“The diagnoses we see are pretty routine,” Jain said.

Chronic conditions pose a much bigger problem. How can patients take regular medications when they don’t have any safe place to keep them? This is the kind of work Zevin does, and beneath his slouch is a strong streak of stubborn optimism.

“After 25 years of national widespread homelessness we’ve actually developed a number of adaptations in practice to make healthcare for chronic conditions doable for homeless people,” he said. “Often, it’s just thinking about it.”

The adaptations can be straightforward: Give a homeless person with diabetes a form of insulin that doesn’t need to be refrigerated, for example.

Image source: Mark Andrew Boyer

But treating homeless patients can require a dramatically different way of thinking about healthcare that focuses on what’s possible, not what’s ideal. A person addicted to heroin who has been infected with HIV is very unlikely to give up heroin on a doctor’s advice.

Instead of pressuring them to get clean, Zevin uses the routine their addiction dictates to make sure they take the medications that make HIV a serious chronic condition rather than a fatal illness.

“How do you take your medicine if you’ve got a chaotic lifestyle?” Zevin said. “Well, what do you do every day? You use heroin every day? Okay, so where in the process of fixing up your heroin are you going to take your HIV meds?”

“Someone who’s routine driven because of schizophrenia or because of an addiction can adhere to medicine,” he concluded.

Rather than giving up on a patient who might need a cocktail of pills for COPD and congestive heart failure, for example, Zevin tries to reduce the total number of pills or the number of daily doses. He also favors medications that are more forgiving of missed doses.  

“Adherence to medications for chronic conditions for substance users and homeless people isn’t really that much worse than it is for anyone else if we make the right accommodations for people,” he said.

The single most powerful intervention is to help a homeless person find a home.

“The way you provide good health for homeless people is to provide them housing,” Jain said.

San Francisco has a housing-first model, where people are not required to get clean before they get subsidized or free housing. Those who need housing are queued partly based on how sick they are. Public housing units often provide healthcare, addiction treatment, and assistance with applying for benefits on-site.

Many of the health risks of homelessness go away with housing, and chronic conditions become easier to treat. So do alcohol and drug abuse.

When the city started providing housing first, the change was noticeable, Zevin said.

“Within a month or two or three, they would come in and say, ‘How do I get off drugs?’ That’s continued as a theme for me. It’s really hard to get off drugs when you’re homeless,” he said. “When we start to treat people as a whole person, we have a lot of people who are interested in making major changes.”

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Healthcare Reform Is a Sea Change

Short of housing, there’s another good lifeline for homeless people who need care: insurance. Many more have gotten it since California expanded Medicaid coverage (called Medi-Cal) under the Affordable Care Act.

Before the reforms, only people with children or a permanent disability, not including substance abuse, qualified. Now nearly all homeless do.

“I tell them, ‘You won the lottery — you have insurance now!’ People are still starting to get it,” Jain said.

With more patients able to see specialists and fill prescriptions, Zevin also says healthcare reform has been a blessing overall. But he also sees downsides to folding these patients into the larger medical system.

That’s because he says public healthcare has at least one thing that care for the privately insured lacks: the human touch. 

Zevin and Jain can, if they see fit, send nurses or caseworkers to check on patients every day or every few days. Those efforts are funded by tax dollars. They offer a clear cost savings over having patients repeatedly wind up in emergency rooms, like Candi Darley did.

“Our medical care for this population is based on individual relationships, it’s based on this rather time-consuming concept,” Zevin said.

At Tom Waddell, patients aren’t passed off from one provider to another during the course of a visit. So much of their openness to treatment is built on personal trust in a system that hasn’t always treated them with compassion.

The current model is one that many are “struggling to make work for us,” Zevin said. Some just have more resources.

Darley makes a similar point: Homeless people are just like the rest of us, only they’ve run out of lifelines.

Darley now lives in public housing across from the National Arboretum. She works as a homeless advocate.

“We really want to break the conception that people are lazy, crazy and/or on drugs,” she said.

The photos that appear with this article, by Mark Andrew Boyer, depict homeless people in the San Francisco Bay Area. They were not interviewed by Healthline.