During a hospital stay, people usually hope to have a medical condition treated effectively so they can recover fully, go home and stay home. But it’s not uncommon for a hospitalization to lead to a new health problem that’s serious enough to require hospital readmission within 30 days.

The phenomenon, dubbed “post-hospital syndrome” by Dr. Harlan Krumholz, a cardiologist and professor of medicine at the Yale School of Medicine, is roughly defined as an acquired, transient period of increased risk for illness after a hospital stay, one that leads to re-hospitalization. Sometimes the readmission is related to the cause of the initial hospitalization, and sometimes it’s because the patient acquired a new infection in the hospital. But often there’s a seemingly new reason for readmission. “Many of us believe that [it] has to do with the hospitalization itself,” Krumholz says. “Exposure to the stress of the hospitalization may have led to a vulnerability afterward.”

This syndrome is more common than you may think. In fact, research from 2009 found that nearly 20 percent of Medicare patients who are discharged from a hospital — which adds up to approximately 2.6 million older adults in the U.S. — develop an acute medical problem within the following 30 days that necessitates another hospitalization. Many of these “new” medical problems have little relation to the original diagnosis.

More recently, a 2015 study from Loyola University in Maywood, Illinois, found that nearly 8 percent of patients who had post-hospital syndrome — because they had been hospitalized in the previous 90 days for gastrointestinal or cardiovascular problems, hip fractures or other conditions — had to be readmitted to the hospital within 30 days of undergoing elective outpatient hernia surgery. In another 2015 study, Yale researchers found that 50 percent of older patients who had been hospitalized for a heart attack were readmitted within a year, and 56 percent of those who had been in the hospital for pneumonia returned for another hospital stay within a year.

Some of this increased vulnerability stems from the overall stress of the hospital experience and the sleep disruption that comes with it, experts say. In addition, people may not get the nutrients or the physical activity they need, which can cause them to become deconditioned during a hospital stay. “People are thrown off their game — the perturbations of the hospitalization seem to affect all of the physiological systems,” Krumholz explains. “We know that when healthy people are sleep-deprived or malnourished or stressed that their immune systems can suffer.” If patients are depressed or anxious or have poor social support, these factors raise their risk of developing post-hospital syndrome even more.

In addition to the risk-producing realities in the hospital, “there’s a new set of self-care activities the patients need to address, such as new medications, new rehabilitation activities and the activities of daily living when the patient leaves,” notes Dr. Aaron Leppin, an assistant professor of health services research in the Knowledge and Evaluation Research Unit at the Mayo Clinic in Rochester, Minnesota. Simply put, a patient’s ability to do what it takes to stay out of the hospital may become compromised. This is especially true, he adds, if the person’s ability to get around physically or cope psychologically are hindered, if the person has no one to help provide physical or emotional support, or the former patient can’t afford to pay for the medications, treatment and care needed.

While “the reason for hospital readmission is often not the same as the reason for original hospitalization, it is always difficult to say that two hospitalizations within a short time-frame are completely unrelated,” says Dr. Hallie Prescott, an assistant professor in the division of pulmonary and critical care medicine at the University of Michigan. “Following a hospitalization, patients are often weak, have changes to their medications — some prescriptions [are] stopped, others [are] started — and are more susceptible to developing additional medical setbacks such as infection. So, while a hospital readmission may be for a new medical problem, it is likely to be related to the original hospitalization at least indirectly.”

Plus, many “health conditions interact in complex ways,” Leppin notes. If a patient has knee replacement surgery and he can’t move around when he gets home, he could become depressed, experience a downturn in immune function and develop a wound infection that could send him back to the hospital. In other words, how well or poorly a patient recovers from one hospitalization could affect his chances of requiring a subsequent hospitalization.

What’s the remedy for post-hospital syndrome? Experts say it needs to start at the hospital, with increased attention to noise-control, proper nutrition, physical activity and other factors that affect patients’ hospital experiences. “We ought to be thinking about how the hospital can become a more supportive and healing environment, a place where we have decreased stress rather than increasing it,” Krumholz says. “It is stressful enough to be sick; we shouldn’t be adding to it.”

Specifically, “there needs to be increased focus on physical therapy and activity during the hospitalization,” Prescott says. “We are increasingly realizing that, especially for patients in intensive care units, bed-rest may be very detrimental. Patients can become weak within just a few days in the hospital, and that makes it harder to care for oneself after going home from the hospital.”

During their hospital stay, patients or their family members should also advocate for quiet periods with no disturbances so they can get the rest they need, experts say. And patients need to communicate with their health care providers about new symptoms because sometimes bringing these to your doctor’s attention may help reduce the risk of re-hospitalization. In a 2014 study, researchers from the University of Michigan reviewed the records of 3,703 patients who had been hospitalized for severe sepsis and found that in the following 90 days, 44 percent were readmitted, primarily for heart failure, pneumonia, exacerbation of chronic obstructive pulmonary disorder, or COPD, and urinary infection; they concluded that of these hospitalizations, 41 percent of the diagnoses were potentially preventable.

As the date of discharge approaches, patients should discuss their needs and concerns with their health care providers and find out what they’ll be expected to do when they get home. This includes making sure you understand the post-hospitalization medication regimen. “Oftentimes, medications are adjusted during a hospitalization so it is important to assess which medications should be stopped or resumed at hospital discharge,” Prescott says.

What’s more, it’s important to make sure that everyone — the patient, family members, hospital doctors and outpatient physicians — are in sync with the post-discharge program. “Make sure to ask questions when the plan doesn’t make sense or seems incomplete,” Prescott advises. “Patients should know what medications to take, what follow-up appointments or additional testing is needed and who to call if they have a question or new symptom.”

Some hospitals have stepped up their post-release efforts by offering home visits or phone calls to check on patients after they’ve been discharged, Leppin notes. “This is especially important in the first 48 hours after discharge as patients figure out what the ‘new normal’ will be for a while.” Another important window is seven to 10 days after discharge, when the consequences of problems that were missed begin manifesting themselves. These follow-up measures can make a difference in reducing the risk of readmission. A 2015 study from the University of San Diego found that remote patient monitoring (aka, telehealth) cuts the rate of hospital readmissions for any cause by more than 50 percent among patients with heart failure.

Once home, patients can take steps to prevent themselves from requiring a return to the hospital by practicing the basics of healthy living — eating well, staying physically active, getting enough sleep and being knowledgeable about their medical condition and potential complications. “Patients know themselves better than anyone else,” Leppin says, “and in most cases they make the decision about whether to go to the hospital.”

So trust your instincts, and let someone know as soon as possible if you need help or are experiencing a complication.

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