Records, posters and toys are among the items in the New York home of a man who said he is making progress in controlling his hoarding. (Seth Wenig/AP)

Sandy Stark always loved pretty things. When she was a girl, she collected unusual rocks, birds’ nests, crooked sticks and dolls. As an adult, she gravitated to white ceramics and china, paperweights, kitchenware and art. Year by year, the treasures accumulated until the only way she could navigate her San Francisco apartment was through a narrow line of what she called “goat paths.”

That was when her two grown daughters swooped in and cleaned the place out. All her treasures, gone. On reentering her house, seeing it so sterile, so empty, Stark, now 71, says she felt traumatized. Almost immediately, she began reacquiring things — with a vengeance:

“You’re pulling everything in around you, building the hamster’s nest, building the wall. Part of it is for the high. It’s an addiction, sort of. But it’s also to fill a void. It fills a lot of void.”

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Within 18 months, Stark, who was at one time so organized she supervised payroll for the Pacific Stock Exchange, could barely negotiate the way to her bedroom. Everywhere she turned, boxes. She was then going on 60, and her life had become defined by “the hoard.”

Compulsive hoarding is more than just keeping your old baseball trophies from middle school. Psychologist Dr. Greg Chasson of Towson University outlines the symptoms of compulsive hoarding and how it can lead to debilitating stress. (Towson University)

While the stockpiling of stuff is often pinned on America’s culture of mass consumption, hoarding is nothing new. But it’s only in recent years that the subject has received the attention of researchers, social workers, psychologists, fire marshals and public-health officials.

They call it an emerging issue that is certain to grow with an aging population. That’s because, while the first signs often arise in adolescence, they typically worsen with age, usually after a divorce, the death of a spouse or another crisis.

Hoarding is different from merely living amid clutter, experts note. It’s possible to have a messy house and be a pack rat without qualifying for a diagnosis of hoarding behavior. The difference is one of degree. Hoarding disorder is present when the behavior causes distress to the individual or interferes with emotional, physical, social, financial or legal well-being.

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“If you aren’t able to use the stove and your refrigerator is stockpiled with expired items, if you’re so disorganized you aren’t able to file for Medicare or make a primary-care appointment, [hoarding] becomes a major problem,” says Catherine Ayers, a geriatric psychologist at the University of California at San Diego who has developed a cognitive behavior therapy for older people with the disorder.

Studies show that compulsive hoarding affects up to 6 percent of the population, or 19 million Americans, and it has been found to run in families. The rate is twice that of obsessive-compulsive disorder, the condition under which hoarding was listed until 2013 in the Diagnostic and Statistical Manual of Mental Disorders, the bible of the American Psychiatric Association. The DSM’s latest version now categorizes it as a separate mental illness.

Brain-imaging studies of hoarders have revealed abnormally low activity in the anterior cingulate cortex, which governs thinking and emotion. When these people are shown trigger images — such as pictures of objects being shredded and discarded — that area of their brain lights up and turns hyperactive.

Hoarding is “underdiagnosed and undertreated,” says Sanjaya Saxena, director of the Obsessive-Compulsive Disorders Program at the UC San Diego health system. “Though people realize it’s a problem, they never conceive of it as a medical disorder rooted in brain abnormalities.”

Awareness, though, is growing. In the past five years, more than 100 task forces on hoarding have sprouted around the United States and Canada. Most involve training and education — teaching clinicians and community figures such as firefighters how to recognize and deal with the disorder.

Many programs use a team approach that may include a landlord, a home-health nurse, a code enforcement officer, firefighters, a family member, a neighbor and a social worker.

“Unlike some other mental-health disorders, many people with hoarding do not seek treatment,” says Michael Tompkins, a San Francisco psychologist and the author of “Digging Out: Helping Your Loved One Manage Clutter, Hoarding and Compulsive Acquiring.” “They don’t recognize the consequences of their condition or the fact that it affects other people in their apartment building and community.”

Compulsive hoarding is associated in various studies with serious health risks such as household falls, obesity, respiratory problems (caused by dust mites and squalor) and poor medication compliance.

A 2012 study in New York found that 22 percent of people threatened with eviction and seeking intervention had a hoarding problem, and the condition has been associated with homelessness.

Among the most serious concerns is the potential for fire. A 2009 study in Australia found that hoarding-related fires ranked among the most deadly of all blazes, with 48 such fires responsible for 10 fatalities over a 10-year period.

“A lot of these people don’t use their front door; a lot of times they don’t use a door at all,” says Ryan Pennington, a paramedic and firefighter who maintains a website called Chamber of Hoarders and who lectures widely to fire departments about the issue. “Firefighters who crawl into these houses often don’t get the full force of radiant heat. Many times, they don’t realize how hot the fire really is until it’s too late.”

Medications — most commonly antidepressants — have been used with some success, but the primary approach to hoarding behavior is psychotherapy and harm reduction. Cognitive behavior therapy is also used, to teach people how to organize, prioritize and plan while working to ease their emotional attachment to the objects they have collected.

The most common acquisitions are clothes and books. But often the stockpiling includes items that people ordinarily discard: junk mail, food packaging, shampoo bottles.

“I call it rubble without a cause,” says Fred Lipschultz, 78, a retired physicist from the University of Connecticut. Over the years, he has hung on to the ticket of virtually every show and concert he has attended. He says he collects papers, plastic containers and quart-size jars. “It does pain me to throw away something that’s useful.”

But in the past few years, he has found help at the Institute for Compulsive Hoarding and Cluttering at the Mental Health Association of San Francisco. He has identified techniques, such as setting limits on how many containers he accumulates, to keep his hoarding in check. He uses a computer to digitize his mementoes, photos, theater tickets and papers. Once something has been scanned into his computer, he allows himself to toss out the actual paper.

Cognitive behavior therapy has its limits, however, said Randy O. Frost, a Smith College researcher who has helped develop a model used around the country to help hoarders address their emotional reactions to reducing their possessions.

“We’ve developed a treatment program, and it does work — but not as well as we’d hoped,” Frost says. “Between 60 and 80 percent of people are improved after treatment, with an average decrease in symptoms of about 30 percent.”

And relapse is common.

Stark says her own experience is “several steps backward while moving forward.”

She dates the beginning of her recovery to the time, about seven years ago, when she saw Tompkins on TV, discussing hoarding behavior and characterizing the people who suffer from it as perfectionists.

“And I thought: ‘That’s me! I’m not this lazy, dirty person! I have a problem.’ Half the relief was knowing that I had an issue I had to address. It was something I had a word for.”

Group therapy proved helpful, and eventually Stark became a member of a peer-led counseling group. But it wasn’t until she found a comrade — a “clutter buddy” — that she began her real recovery.

“It took me three years to accept her offer, and even then I cried as she came over the threshold,” Stark says. It was the first time in many years that she had allowed anyone inside her house.

Now her goal is to open her home to a host of friends. And she knows just how she wants to do it.

“I’m going to have an old-fashioned cocktail party,” says Stark, who loved entertaining before her hoarding began. “That’s my eye on the prize.”