Combination of weak muscles and abdominal obesity can be an early sign of functional decline in men

A study conducted at the Federal University of São Carlos (UFSCar) in Brazil suggests that early detection of functional decline – the dwindling capacity to perform everyday tasks independently – is possible by observing patients as they engage in simple actions such as sitting down and getting up from a chair, standing still, and walking a short distance. An article on the study is published in The American Journal of Clinical Nutrition. 

According to the article, the findings are valid mainly for men with abdominal obesity combined with loss of muscle strength. The study was conducted during the PhD research of Roberta de Oliveira Máximo under the aegis of UFSCar’s Program of Graduate Studies in Physical Therapy, with support from FAPESP and supervision by Professor Tiago da Silva Alexandre. Researchers at University College London in the UK collaborated. 

The group analyzed data for 3,875 individuals aged 60 or more that were monitored for eight years by the English Longitudinal Study of Ageing (ELSA). They were scored according to the Short Physical Performance Battery (SPPB), widely used by health workers everywhere. The battery covers gait speed while walking 2.4m, static balance, and a chair sit-to-stand test, among other metrics.

“Impaired physical performance is the first sign of functional decline in the elderly. It’s considered a pre-clinical transition stage toward incapacity, appearing before difficulties are experienced with everyday activities such as using public transport, shopping, doing housework, cooking, bathing, getting dressed, and taking meals,” Alexandre said. “Early diagnosis could help prevent older people from becoming unable to perform these day-to-day tasks.”

Assessment of functional physical performance, he explained, is an objective evaluation of the ability to carry out specific tasks based on set criteria such as scores, repetitions or time taken. It differs from a subjective evaluation of functional status, which involves individuals self-reporting the activities they are capable or incapable of performing.

Physical performance is considered the sixth vital sign in assessing the elderly. The complete SPPB takes about 15 minutes and, despite the extra time required, may offer more explanatory power than a walking speed test on its own. “A poor SPPB score would seem to be an earlier marker than slow walking speed,” Alexandre said.

The researchers detected impairment of physical performance mostly in men with abdominal obesity as well as age-associated loss of muscle strength (dynapenia), a phenotype common among older people. The study identified dynapenic abdominal obesity in men with a waist circumference of more than 102 cm and handgrip of less than 26 kg; the corresponding criteria for women were 88 cm or more and less than 16 kg respectively. Handgrip was measured using a dynamometer. Handgrip strength is often considered a proxy for overall bodily muscle strength.

“Men and women alike lose muscle strength and accumulate abdominal fat as they age, but the situation is worse for men,” Máximo said. “Men lose more muscle strength than women during their lifetime and tend to accumulate abdominal fat even before they’re elderly. Abdominal fat is more active metabolically and generates low-level inflammation, with negative repercussions for muscle function. This explains the differences between the sexes, and why dynapenic abdominal obesity affects physical performance more in men.”

In contrast, dynapenia combined with general obesity defined in terms of body mass index (BMI) did not correlate with declining physical performance in men or women, suggesting that diagnosing obesity on the basis of BMI cannot account for the impact on physical performance of age-related changes in body fat distribution.

Another important finding was that neither abdominal obesity nor dynapenia on their own was associated with declining physical performance over time in elderly men and women, showing that assessing these two conditions separately rather than the phenotype of dynapenia abdominal obesity may underestimate the problem of age-related functional decline.

According to Alexandre, one of the main messages of the research is that identifying and clinically managing the dynapenic abdominal obesity phenotype is essential to stave off the first signs of functional decline in older men.

“The clinical importance of these findings is that although dynapenic abdominal obesity is an age-related condition, it is potentially modifiable and neglecting it has major repercussions for functional status, especially in men,” he said. “The 2020 World Health Organization guidelines recommend that men aged 65 or more should regularly perform a number of aerobic exercises and muscle-strengthening activities. They should get at least 150 to 300 minutes of moderately intense exercise or 75 to 150 minutes of vigorous aerobic exercise each week. As part of their weekly physical activity, they should also practice strength training of all the main muscle groups on three or more days each week.”

The study was funded by FAPESP via a Young Investigator Grant awarded to Alexandre.

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About São Paulo Research Foundation (FAPESP)

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.