Nearly 18 months after getting covid-19 and spending weeks in the hospital, Terry Bell struggles with hanging up his shirts and pants after doing the laundry.

Lifting his clothes, raising his arms, arranging items in his closet leave Bell short of breath and often trigger severe fatigue. He walks with a cane, only short distances. He's 50 pounds lighter than when the virus struck.

Bell, 70, is among millions of older adults who have grappled with long covid — a population that has received little attention even though research suggests seniors are more likely to develop the poorly understood condition than younger or middle-aged adults.

Long covid refers to ongoing or new health problems that occur at least four weeks after a covid infection, according to the Centers for Disease Control and Prevention. Much about the condition is baffling: There is no diagnostic test to confirm it, no standard definition of the ailment, and no way to predict who will be affected. Common symptoms, which can last months or years, include fatigue, shortness of breath, an elevated heart rate, muscle and joint pain, sleep disruptions, and problems with attention, concentration, language, and memory — a set of difficulties known as brain fog.

Ongoing inflammation or a dysfunctional immune response may be responsible, along with reservoirs of the virus that remain in the body, small blood clots, or residual damage to the heart, lungs, vascular system, brain, kidneys, or other organs.

Only now is the impact on older adults beginning to be documented. In the largest study of its kind, published recently in the journal BMJ, researchers estimated that 32% of older adults in the U.S. who survived covid infections had symptoms of long covid up to four months after infection — more than double the 14% rate an earlier study found in adults ages 18 to 64. (Other studies suggest symptoms can last much longer, for a year or more.)

The BMJ study examined more than 87,000 adults 65 and older who had covid infections in 2020, drawing on claims data from UnitedHealth Group's Medicare Advantage plans. It included symptoms that lasted 21 days or more after an infection, a shorter period than the CDC uses in its long covid definition. The data encompasses both older adults who were hospitalized because of covid (27%) and those who were not (73%).

The higher rate of post-covid symptoms in older adults is likely due to a higher incidence of chronic disease and physical vulnerability in this population — traits that have led to a greater burden of serious illness, hospitalization, and death among seniors throughout the pandemic.

"On average, older adults are less resilient. They don't have the same ability to bounce back from serious illness," said Dr. Ken Cohen, a co-author of the study and executive director of translational research for Optum Care. Optum Care is a network of physician practices owned by UnitedHealth Group.

Applying the study's findings to the latest data from the CDC suggests that up to 2.5 million older adults may have been affected by long covid. For those individuals, the consequences can be devastating: the onset of disability, the inability to work, reduced ability to carry out activities of daily life, and a lower quality of life.

But in many seniors, long covid is difficult to recognize.

"The challenge is that nonspecific symptoms such as fatigue, weakness, pain, confusion, and increased frailty are things we often see in seriously ill older adults. Or people may think, 'That's just part of aging,'" said Dr. Charles Thomas Alexander Semelka, a postdoctoral fellow in geriatric medicine at Wake Forest University.

Ann Morse, 72, of Nashville, Tennessee, was diagnosed with covid in November 2020 and recovered at home after a trip to the emergency room and follow-up home visits from nurses every few days. She soon began having trouble with her memory, attention, and speech, as well as sleep problems and severe fatigue. Though she's improved somewhat, several cognitive issues and fatigue persist to this day.

"What was frustrating was I would tell people my symptoms and they'd say, 'Oh, we're like that too,' as if this was about getting older," she told me. "And I'm like, but this happened to me suddenly, almost overnight."

Bell, a singer-songwriter in Nashville, had a hard time getting adequate follow-up attention after spending two weeks in intensive care and an additional five weeks in a nursing home receiving rehabilitation therapy.

"I wasn't getting answers from my regular doctors about my breathing and other issues. They said take some over-the-counter medications for your sinus and things like that," he said. Bell said his real recovery began after he was recommended to specialists at Vanderbilt University Medical Center.

James Jackson, director of long-term outcomes at Vanderbilt's Critical Illness, Brain Dysfunction, and Survivorship Center, runs several long covid support groups that Morse and Bell attend and has worked with hundreds of similar patients. He estimates that about a third of those who are older have some degree of cognitive impairment.

"We know there are significant differences between younger and older brains. Younger brains are more plastic and effective at reconstituting, and our younger patients seem able to regain their cognitive functioning more quickly," he said.

In extreme cases, covid infections can lead to dementia. That may be because older adults who are severely ill with covid are at high risk of developing delirium — an acute and sudden change in mental status — which is associated with the subsequent development of dementia, said Dr. Liron Sinvani, a geriatrician and an assistant professor at Northwell Health's Feinstein Institutes for Medical Research in Manhasset, New York.

Older patients' brains also may have been injured from oxygen deprivation or inflammation. Or disease processes that underlie dementia may already have been underway, and a covid infection may serve as a tipping point, hastening the emergence of symptoms.

Research conducted by Sinvani and colleagues, published in March, found that 13% of covid patients who were 65 and older and hospitalized at Northwell Health in March 2020 or April 2020 had evidence of dementia a year later.

Dr. Thomas Gut, associate chair of medicine at Staten Island University Hospital, which opened one of the first long covid clinics in the U.S., observed that becoming ill with covid can push older adults with preexisting conditions such as heart failure or lung disease "over the edge" to a more severe impairment.

In older adults especially, he said, "it's hard to attribute what's directly related to covid and what's a progression of conditions they already have."

That wasn't true for Richard Gard, 67, who lives just outside New Haven, Connecticut, a self-described "very healthy and fit" sailor, scuba diver, and music teacher at Yale University who contracted covid in March 2020. He was the first covid patient treated at Yale New Haven Hospital, where he was critically ill for 2½ weeks, including five days in intensive care and three days on a ventilator.

In the two years since, Gard has spent more than two months in the hospital, usually for symptoms that resemble a heart attack. "If I tried to walk up the stairs or 10 feet, I would almost pass out with exhaustion, and the symptoms would start — extreme chest pain radiating up my arm into my neck, trouble breathing, sweating," he said.

Dr. Erica Spatz, director of the preventive cardiovascular health program at Yale, is one of Gard's physicians. "The more severe the covid infection and the older you are, the more likely it is you'll have a cardiovascular complication after," she said. Complications include weakening of the heart muscle, blood clots, abnormal heart rhythms, vascular system damage, and high blood pressure.

Gard's life has changed in ways he never imagined. Unable to work, he takes 22 medications and can still walk only 10 minutes on level ground. Post-traumatic stress disorder is a frequent, unwanted companion.

"A lot of times it's been difficult to go on, but I tell myself I just have to get up and try one more time," he told me. "Every day that I get a little bit better, I tell myself I'm adding another day or week to my life."

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This article was reprinted from khn.org with permission from the Henry J. Kaiser Family Foundation. Kaiser Health News, an editorially independent news service, is a program of the Kaiser Family Foundation, a nonpartisan health care policy research organization unaffiliated with Kaiser Permanente.