How much does physical activity help with CF?

The effects of cystic fibrosis (CF), such as pancreatic dysfunction, elevated electrolytes in sweat, and male infertility, can have a cumulative effect over time that imposes a high therapeutic burden. Together with the suffering caused by the disease, this can affect the physical activity of those affected. In a review paper, correlations were put under the microscope.

The immediate and long-term benefits of regular physical activity for people in good general health have been widely demonstrated. And for people with cystic fibrosis, research also suggests that there are specific health benefits, such as.

slower deterioration of lung function
Fewer hospitalizations
Improvement in quality of life (QoL) and nutritional status.
Improving prognosis in both children and adults with cystic fibrosis.

Higher levels of intense physical activity (KA), referred to as moderate-to-intense (MIKA) and intense (IKA), enhance long-term health protection compared with relatively low levels, write Dr. Manon Kinaupenne of Ghent University and colleagues [1]. In fact, when there is an overall decrease in KA, an increase in cases of severe disease is observed.

In 2020, WHO published new KA guidelines for the general population, but to date there are no such criteria specifically for people with cystic fibrosis. The ERR (European Respiratory Review) reviewed the literature on KA levels in people with CF compared with healthy peers and identified general and disease-specific correlates of KA levels in CF patients to develop future interventions for this group.

Intensive training improves lung function

The review found that light (LKA) and total physical activity levels in people with CF were comparable to those in the healthy population, although time spent in M(I)KA was less frequent, and specifically in younger CF patients. The benefits of KA are shown in terms of quality of life, lung function, maximal physical performance, and bone mineral density, among others.

Due to the limited aerobic capacity, one has to rely more on anaerobic metabolism during physical activity. As a result, there is higher lactate and carbon dioxide production, which stresses the respiratory system. The associated discomfort probably discourages some of the younger CF patients from moving on to more intense activity. Some studies support the notion that younger people with CF have generally lower aerobic fitness compared with healthy peers. Further confirmation of this hypothesis comes from the relatively early decline in MICA in preclinical patients with chronic obstructive disease. What is clear, however, is that neither group (healthy or not) achieves the recommended 60 minutes of daily exercise.

Studies focusing on both healthy populations and diseased individuals have shown that prolonged periods of impaired M(I)KA are a precursor to earlier onset of obesity and noncommunicable diseases in adulthood (e.g., cardiovascular and metabolic diseases).

With the development of CFTR** modulators, 80% of CF patients have the option of such therapy, which improves lung function; with the newest of these modulators, a 15% improvement in _FEV1 has been observed. They also show promise in other areas, but more research is needed; data on how CFTR modulators affect exercise performance are also currently limited. Knowing that 20% of patients are not eligible for these modulators could drive the development of KA interventions that could be integrated as part of a more patient-specific treatment regimen.

** CFTR = Transmembrane Conductance Regulator

Positive correlation also between KA and quality of life

The quality of life of people with CF is generally described as poor, and there is some evidence of a positive association between KA and quality of life in this population. However, due to the limited data available and the quality of the existing data, there are more questions than answers when it comes to making recommendations on the ideal times for a potential KA routine. More studies are needed to determine whether time and routine matter and whether or not certain recommendations should be gender-specific, the authors write.

One sign of disease progression is decreased lung function, which in turn is associated with reduced M(I)KA levels; this mirrors results observed in other groups with chronic respiratory disease. Impaired pulmonary function increases the risk of pulmonary exacerbation, which has the expected domino effect on KA.

Further research on the question of therapy is needed, the researchers conclude. Some issues considered particularly relevant for further investigation in the review, he said, are which modifiable intrapersonal factors determine KA levels in CF patients and how these differ from those in the healthy population, and the extent to which therapy with CFTR modulators plays a role.

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