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  • A new study found that people who carried excess weight in midlife had a higher risk of being pre-frail or frail 21 years later.
  • This could potentially impact their quality of life as they age.
  • Older adults who are frail have a higher risk of falling and being injured, being hospitalized and experiencing complications due to that hospitalization.

Frailty in older age is sometimes perceived as a loss of weight — including muscle mass — as people age, but new research suggests that weight gain may also play a role in the development of this condition.

In the study, published Jan. 23 in the journal BMJ Open, researchers from Norway found that people who carried excess weight in midlife — as measured by body mass index (BMI) or waist circumference — had a higher risk of being pre-frail or frail 21 years later.

This could potentially impact their quality of life as they age.

“Frailty is a powerful barrier to aging successfully and on one’s own terms,” said Nikhil Satchidanand, PhD, an exercise physiologist and assistant professor at the University at Buffalo, who was not involved in the new study.

Older adults who are frail have a higher risk of falling and being injured, being hospitalized and experiencing complications due to that hospitalization, he said.

In addition, frail older adults are more likely to experience declines that result in a loss of independence and the need to enter a long-term care facility, he said.

The findings of the new study fit with those of previous long-term studies which found a link between midlife obesity and pre-frailty/frailty later on.

However, this is an observational study, so the researchers could not prove direct cause and effect.

Researchers also didn’t track changes in participant’s lifestyle, diet, habits and friendship networks during the study, all of which could have impacted their risk of developing frailty.

But the authors write that the results of the study highlight the “importance of routinely assessing and maintaining optimal BMI and [waist circumference] throughout adulthood to lower the risk of frailty in older age.”

The study was based on data from surveys of over 4,500 residents of Tromsø, Norway, aged 45 or older, between 1994 and 2015.

Participants had their height and weight measured at each survey. This was used to calculate BMI, which is a screening tool for weight categories that may lead to health problems. A higher BMI does not always indicate higher body fat.

Participants also had their waist circumference measured during some of the surveys; this is used to estimate abdominal fat.

In addition, researchers determined frailty based on the following criteria: unintentional weight loss; exhaustion; weak grip strength; slow walking speed; and low physical activity levels.

Frailty was characterized by the presence of at least three of those criteria, and pre-frailty by one or two of them.

Because only 1% of participants had frailty at the final follow-up visit, researchers grouped these people together with the 28% who had pre-frailty.

The analysis showed that people who had obesity in mid-life, as indicated by a higher BMI, were nearly 2.5 times more likely to be pre-frail/frail 21 years later, compared to those with a normal BMI.

In addition, those with a moderately high or a high waist circumference were up to twice as likely to be pre-frail/frail at the final follow-up visit than those with a normal waistline.

Researchers also found that people were more likely to be pre-frail/frail at the end of the study period if they had gained weight or if their waistline had increased during that time.

Satchidanand said the study provides additional evidence that early adoption of healthy lifestyle choices can help support successful aging.

“This study should remind us that the negative consequences of increasing adiposity beginning in earlier adulthood are far-reaching,” he said, “and will significantly impact overall health, functional capacity and quality of life in older age.”

Dr. David Cutler, a family medicine physician at Providence Saint John’s Health Center in Santa Monica, Calif., said one shortcoming of the study is that the researchers focused on the physical aspects of frailty.

In contrast, “most people in the general public would look at frailty as decreased physical and cognitive functioning,” he said.

While the physical criteria used by the researchers in this study have been applied in other studies, some researchers have attempted to take into account other aspects of frailty, such as cognitive, social, and psychological dimensions.

In addition, Cutler said some of the frailty measures in the new study were reported by the participants themselves — such as exhaustion, low physical activity, and unintentional weight loss — which means they may not be as accurate.

Another limitation pointed out by Cutler is that some people dropped out of the study before the final follow-up visit. These people tended to be older, with a higher level of obesity and other risk factors for frailty, the researchers found.

However, when researchers excluded people who were over 60 years old at the start of the study, the results were similar.

While earlier research has found an increased risk of frailty among underweight women, there were too few underweight people in the new study for the researchers to examine this connection.

In spite of the observational nature of the study, the researchers suggested several possible biological mechanisms for their findings.

Increased fat deposits may contribute to inflammation in the body, which is also associated with frailty. The deposition of fat in muscle fibers may also contribute to reduced muscle strength, they wrote.

Dr. Mir Ali, a bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, Calif., said obesity can impact later-life functioning in other ways.

“My patients who are obese tend to have more joint issues and more back problems,” he said. “This can affect their mobility and their ability to have a decent quality of life, including as they get to an older age.”

Although frailty is related, in part, to aging, Satchidanand said it’s important to remember that not every older adult becomes frail.

In addition, “while the underlying mechanisms of frailty are very complex and multidimensional, we do have a degree of control over many of the factors that drive frailty,” he said.

Lifestyle choices such as regular physical activity, reasonable nutrition, proper sleep hygiene and stress management have been shown to impact weight gain in adulthood, he said.

However, Ali said maintaining a healthy weight is sometimes complicated.

“There are a multitude of factors that contribute to obesity,” he said, including genetics, hormones, access to quality foods, and a person’s education, income and occupation.

Although Cutler has some concerns about the study’s limitations, he said the research does show that doctors, patients, and society should be aware of the issue of frailty.

“We don’t really know what to do about frailty. We don’t necessarily know how to prevent it. But we should be aware of it,” he said.

Satchidanand said increased awareness of frailty is especially important given the aging of the population.

“As our global society continues to age rapidly and our average life expectancy increases, we are being confronted with the need to better understand the underlying mechanisms that drive frailty,” he said, “and to develop effective and manageable strategies to both prevent and treat frailty syndrome.”