A study by researchers from the Federal University of San Carlos (UFSCar) in Brazil and University College London (UCL) in the United Kingdom shows that the combination of anemia and muscle weakness in older people increases the risk of death in ten years by 64%. in men and 117% in women.
Anemia alone increases the risk of death in men by 58%. For women, dynaponia (loss of muscle strength) is itself a more important risk factor, increasing the risk of death by 68%. These two conditions together pose an even greater risk, especially for older women, according to a study article published in Archive of Gerontology and Geriatrics.
“In the case of women, the risk of death doubles when the two conditions are combined. This is a very significant increase, so these factors should be monitored clinically. When patients go to the doctor, the cause of any anemia should be established. quickly and treat. It is also important to find out the cause of any muscle weakness and prescribe weight training,” said Marian Marquez Luis, PhD in Physical Therapy at UFSCar and first author of the FAPESP-supported study article.
The researchers analyzed data from 5,310 English people aged 50 and over who were followed for ten years by the English Longitudinal Study of Aging (ELSA). According to Marquez Luis, the analysis took into account the fact that the overall risk of mortality was higher in participants with anemia and dyspepsia, regardless of factors such as age, marital status, smoking, physical activity level, memory scores, difficulty with instrumental activities in daily life. . life (IADL), heart disease, lung disease and cancer.
We analyzed all causes of death, and the results showed that the combination of anemia and dyspepsia increases the risk of all-cause mortality. The presence of both anemia and dynapenia poses a significant risk for older adults, regardless of these issues.”
Marian Marquez Luis, Ph.D. PhD in Physiotherapy at UFSCar
Of the 5,310 subjects analyzed in the study, 84% had neither anemia nor dynapenia, while 10.7% had dynapenia, 3.8% had anemia, and 1.5% had both. .
In total, 984 deaths were registered among the studied samples during the ten-year follow-up period. Of the deceased, 63.7% had neither anemia nor dynaponia, 22.8% – dynaponia, 7.5% – anemia, 6% – both.
Decreased supply of oxygen to muscles
Previous research has shown that anemia is a risk factor for reduced muscle strength because oxygen is taken up by iron in red blood cells, and in an anemic person, less oxygen reaches the body tissues. Muscles weaken due to impaired oxygenation.
The problem of poor oxygenation is what scientists call hypoxia, which affects not only the muscles, but also all organs and systems of the body. “Hypoxia can cause a number of changes in the body, such as peripheral arterial vasodilation and reduced capillary formation. It can also cause myocardial dysfunction and inappropriately activate [ renin-angiotensin-aldosterone ] hormonal system that, among other things, controls blood pressure,” said Thiago da Silva Alexander, professor of gerontology at UFSCar and author of the paper.
All these effects of hypoxia increase the risk of cardiovascular disease and overall mortality. “When older people are anemic, they are more likely to have dyspnea, and when they have both conditions together, the problem becomes even more difficult because, in addition to hemoglobin and iron deficiencies, [ characteristic of iron-deficiency anemia ]low production of erythrocytes and iron negatively affects the musculoskeletal system, ”said Alexander.
Higher risk for women
In addition to examining the combined effects of anemia and dynaponia on the risk of death in the elderly, the researchers also set out to investigate whether their effects differ between men and women. The results showed that both conditions were more common in women, and their combination was even more dangerous for them than for men.
“First of all, there is a mathematical question. Anemia is slightly more common in women than in men. It is worth noting that the threshold values for determining anemia are different for each gender,” Alexander said.
However, women seem to be more likely to suffer from the effects of anemia on skeletal muscle. “This difference may be due to the fact that men tend to have more muscle mass than women, so when men are anemic, the musculoskeletal system suffers less. This is just one of the possible explanations,” he said.
He added that dipenia itself poses a mortality risk for women, but not anemia per se. “Women typically lose muscle mass as they age, and it can happen that anemia exacerbates this loss,” he said.
While men tend to have more muscle mass, they lose muscle mass faster than women as they age. “However, because women generally have less muscle mass, their strength can decrease over time, and this affects mortality. Dynamism is a sign that something is wrong with the health of an elderly person, ”he said.