Nothing prepared Linda C. Johnson of Indianapolis for the fatigue that descended on her after a diagnosis of stage 4 lung cancer in early 2020.

Initially, Johnson, now 77, thought she was depressed. She could barely summon the energy to get dressed in the morning. Some days, she couldn’t get out of bed.

But as she began to get her affairs in order, Johnson realized something else was going on. However long she slept the night before, she woke up exhausted. She felt depleted, even if she didn’t do much during the day.

“People would tell me, ‘You know, you’re getting old.’ And that wasn’t helpful at all. Because then you feel there’s nothing you can do mentally or physically to deal with this,” she told me.

Fatigue is a common companion of many illnesses that beset older adults: heart disease, cancer, rheumatoid arthritis, lung disease, kidney disease, and neurological conditions like multiple sclerosis, among others. It’s one of the most common symptoms associated with chronic illness, affecting 40% to 74% of older people living with these conditions, according to a 2021 review by researchers at the University of Massachusetts.

This is more than exhaustion after an extremely busy day or a night of poor sleep. It’s a persistent whole-body feeling of having no energy, even with minimal or no exertion. “I feel like I have a drained battery pretty much all of the time,” wrote a user named Renee in a Facebook group for people with polycythemia vera, a rare blood cancer. “It’s sort of like being a wrung-out dish rag.”

Fatigue doesn’t represent “a day when you’re tired; it’s a couple of weeks or a couple of months when you’re tired,” said Dr. Kurt Kroenke, a research scientist at the Regenstrief Institute in Indianapolis, which specializes in medical research, and a professor at Indiana University’s School of Medicine.

When he and colleagues queried nearly 3,500 older patients at a large primary care clinic in Indianapolis about bothersome symptoms, 55% listed fatigue — second only to musculoskeletal pain (65%) and more than back pain (45%) and shortness of breath (41%).

Separately, a 2010 study in the Journal of the American Geriatrics Society estimated that 31% of people 51 and older reported being fatigued in the past week.

The impact can be profound. Fatigue is the leading reason for restricted activity in people 70 and older, according to a 2001 study by researchers at Yale. Other studies have linked fatigue with impaired mobility, limitations in people’s abilities to perform daily activities, the onset or worsening of disability, and earlier death.

What often happens is older adults with fatigue stop being active and become deconditioned, which leads to muscle loss and weakness, which heightens fatigue. “It becomes a vicious cycle that contributes to things like depression, which can make you more fatigued,” said Dr. Jean Kutner, a professor of medicine and chief medical officer at the University of Colorado Hospital.

A photo of an older woman smiling.
Linda C. Johnson began experiencing fatigue after a diagnosis of stage 4 lung cancer in early 2020. Fatigue is a common companion of many illnesses that beset older adults.(Linda C. Johnson)

To stop that from happening, Johnson came up with a plan after learning her lung cancer had returned. Every morning, she set small goals for herself. One day, she’d get up and wash her face. The next, she’d take a shower. Another day, she’d go to the grocery store. After each activity, she’d rest.

In the three years since her cancer came back, Johnson’s fatigue has been constant. But “I’m functioning better,” she told me, because she’s learned how to pace herself and find things that motivate her, like teaching a virtual class to students training to be teachers and getting exercise under the supervision of a personal trainer.

When should older adults be concerned about fatigue? “If someone has been doing OK but is now feeling fatigued all the time, it’s important to get an evaluation,” said Dr. Holly Yang, a physician at Scripps Mercy Hospital in San Diego and incoming board president of the American Academy of Hospice and Palliative Medicine.

“Fatigue is an alarm signal that something is wrong with the body but it’s rarely one thing. Usually, several things need to be addressed,” said Dr. Ardeshir Hashmi, section chief of the Center for Geriatric Medicine at the Cleveland Clinic.

Among the items physicians should check: Are your thyroid levels normal? Are you having trouble with sleep? If you have underlying medical conditions, are they well controlled? Do you have an underlying infection? Are you chronically dehydrated? Do you have anemia (a deficiency of red blood cells or hemoglobin), an electrolyte imbalance, or low levels of testosterone? Are you eating enough protein? Have you been feeling more anxious or depressed recently? And might medications you’re taking be contributing to fatigue?

“The medications and doses may be the same, but your body’s ability to metabolize those medications and clear them from your system may have changed,” Hashmi said, noting that such changes in the body’s metabolic activity are common as people become older.

Many potential contributors to fatigue can be addressed. But much of the time, reasons for fatigue can’t be explained by an underlying medical condition.

That happened to Teresa Goodell, 64, a retired nurse who lives just outside Portland, Oregon. During a December visit to Arizona, she suddenly found herself exhausted and short of breath while on a hike, even though she was in good physical condition. At an urgent care facility, she was diagnosed with an asthma exacerbation and given steroids, but they didn’t help.

Soon, Goodell was spending hours each day in bed, overcome by profound tiredness and weakness. Even small activities wore her out. But none of the medical tests she received in Arizona and subsequently in Portland — a chest X-ray and CT scan, blood work, a cardiac stress test — showed abnormalities.

“There was no objective evidence of illness, and that makes it hard for anybody to believe you’re sick,” she told me.

Goodell started visiting long covid web sites and chat rooms for people with chronic fatigue syndrome. Today, she’s convinced she has post-viral syndrome from an infection. One of the most common symptoms of long covid is fatigue that interferes with daily life, according to the Centers for Disease Control and Prevention.

There are several strategies for dealing with persistent fatigue. In cancer patients, “the best evidence favors physical activity such as tai chi, yoga, walking, or low-impact exercises,” said Dr. Christian Sinclair, an associate professor of palliative medicine at the University of Kansas Health System. The goal is to “gradually stretch patients’ stamina,” he said.

With long covid, however, doing too much too soon can backfire by causing “post-exertional malaise.” Pacing one’s activities is often recommended: doing only what’s most important, when one’s energy level is highest, and resting afterward. “You learn how to set realistic goals,” said Dr. Andrew Esch, senior education advisor at the Center to Advance Palliative Care.

Cognitive behavioral therapy can help older adults with fatigue learn how to adjust expectations and address intrusive thoughts such as, “I should be able to do more.” At the University of Texas MD Anderson Cancer Center, management plans for older patients with fatigue typically include strategies to address physical activity, sleep health, nutrition, emotional health, and support from family and friends.

“So much of fatigue management is about forming new habits,” said Dr. Ishwaria Subbiah, a palliative care and integrative medicine physician at MD Anderson. “It’s important to recognize that this doesn’t happen right away: It takes time.”

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