The condition raises the risk of dying over ten years by 64% for men and 117% for women.
A study carried out by researchers from the Federal University of São Carlos (UFSCar) and University College London (United Kingdom) indicates that the The combination of anemia and muscle weakness in the elderly increases the risk of dying over ten years by 64% for men and 117% for women.
Anemia alone already increases the risk of dying by 58% in the case of elderly men. For women, muscle weakness is, in isolation, a more important risk factor, increasing the risk of death by 68%. And, according to the study published in the Archives of Gerontology and Geriatrics, the two conditions together pose an even bigger problem, especially for females.
“For women, the two conditions combined double the risk of death. It is a very large increase and therefore these factors need to be monitored in the clinic. When the patient goes to the office, it is up to the doctor to quickly identify the cause of anemia and treat it, in addition to discovering the reason for the weakness and indicating resistance exercise”, says Mariane Marques Luiz, doctoral student of the Postgraduate Program in Physiotherapy at UFSCar and author of the study.
The group analyzed a database of 5,310 British elderly people followed up for ten years as part of the English Longitudinal Study of Aging (Elsa) project. The work was supported by FAPESP.
Marques Luiz emphasizes that general mortality data were considered and that the risk was greater for patients with both conditions regardless of factors such as: age, cigarette consumption, marital status, level of physical activity, memory performance, difficulty in instrumental activity and the presence of heart, lung or cancer disease.
“We looked at all causes of death and the results showed that the combination of these two conditions increases the risk of overall mortality. This means that regardless of these problems, when you get older, having anemia and dynapenia [fraqueza muscular] becomes an important risk factor”, says Marques Luiz.
Among the 5,310 subjects analyzed in the study, 84% had neither anemia nor muscle weakness. Only 10.7% had dynapenia (loss of muscle strength related to aging), 3.8% had anemia and 1.5% lived with both conditions.
Over the ten-year follow-up of the participants, 984 deaths occurred among these individuals, of whom 63.7% had neither condition. 22.8% were dynapenic, 7.5% anemic, and 6% had coexisting dynapenia and anemia.
Previous studies had already shown that anemia is a predisposing factor to loss of muscle strength. This is because for an anemic person it is more difficult for oxygen – captured in the red blood cells, a type of blood cell that is reduced when there is iron deficiency – to reach the muscle tissue. As a result of this deficient process, muscle oxygenation is impaired. This condition, known as hypoxia, affects every organ and tissue in the anemic organism.
“By itself, hypoxia can generate a series of changes in the body, such as peripheral arterial vasodilation and decreased capillary formation. It can also trigger heart dysfunction and inappropriately activate a protein system. [renina-angiotensina-aldosterona] that controls, among other things, blood pressure”, explains Tiago da Silva Alexandre, professor at the Department of Gerontology at UFSCar and research advisor.
The researcher points out that all these consequences of hypoxia can be reflected in the increased risk of both cardiovascular disease and mortality in general.
“When an elderly person has anemia, he is more likely to have dynapenia. And when he has the two conditions together we have an even more complex problem. This is because in addition to the lack of hemoglobin and iron, there is an impact of the low production of red blood cells in the musculoskeletal system”, he explains.
Differences between the sexes
In addition to investigating the combined effect of anemia and dynapenia in the elderly, the researchers also looked at whether the impact is different in men and women. According to the results of the study, in addition to having a higher incidence of both problems in women, the combination of these two conditions is even more dangerous for them.
“First, there is a math issue. Among women, the prevalence of anemia is slightly higher. It is worth noting that the cut-off points are also different to define anemia in men and women”, says Alexandre.
However, women appear to be more susceptible to the impact of anemia on the musculoskeletal system. “This difference may be due to the fact that men generally have more muscle mass and, when they have anemia, the musculoskeletal system is less affected. But this is just one of the possible explanations.
Alexandre points out that dynapenia alone was a risk factor for mortality for women, whereas anemia was not. “As women generally have a significant loss of muscle mass with aging, there may already be a loss of muscle mass that will be accentuated by anemia”, she explains.
Men, although they generally have more lean mass, lose muscle faster than women during the aging process. “But women generally have a lower amount of muscle mass and this can lead to a reduction in strength over time, which impacts mortality. Dynapenia is an indicator that something is not going well in the health of the elderly”, he warns.