Poorer heart and lung function appears to be related to an increased risk of cardiovascular disease in people with ankylosing spondylitis, reported a study that suggested more aerobic exercises might be a way of improving patients’ cardiovascular fitness.
Physical activity is a cornerstone of treatment for ankylosing spondylitis, but traditionally the focus has been on flexibility exercises. Most patients report performing low-intensity exercises, which are not designed to address cardiorespiratory fitness, defined as the ability of the heart and lung systems to supply oxygen to the muscles during physical activity.
Cardiorespiratory fitness is linked to heart disease or its prevention in the general population. And in patients at risk of heart disease, like those with diabetes, high-intensity or aerobic exercise is generally recommended to reduce such risk.
Previous research has also shown that people with ankylosing spondylitis are more likely to have arterial stiffness, or hardening of the arteries, a known marker for cardiovascular disease.
Researchers from the Diakonhjemmet Hospital in Norway and the Leiden Medical Center in the Netherlands evaluated cardiorespiratory fitness in 118 ankylosing spondylitis patients, measured as the maximum amount of oxygen one can consume during a walking test on a treadmill (VO2 peak), and their risk for heart diseases as measured by blood pressure and hardening of arteries — the vessels conducting blood from the heart to other organs.
Participants completed a questionnaire that included information on demographics, height and weight, medical history, medications, and disease activity as measured by the AS Disease Activity Score (ASDAS)-CRP and the Bath AS Disease Activity Index.
The ASDAS-CRP is an index that combines five disease activity variables into one score to evaluate disease activity, along with C-reactive protein values — a known marker of inflammation. The Bath AS Disease Activity Index is a diagnostic test that evaluates discomfort, pain, and fatigue (on a rising 0–10 scale) to help clinicians to determine the effectiveness of a therapy.
Results revealed an inverse relationship between VO2 peak and arterial hardening, independent of pre-existing risk factors of heart disease and measures of disease activity.
“We found that low VO2peak was associated with higher arterial stiffness in patients with AS [ankylosing spondylitis], indicating that low cardiorespiratory fitness is associated with increased cardiovascular disease risk,” the researchers wrote.
“High-intensity exercises aiming at improving [cardiorespiratory fitness] may be an attractive way to reduce arterial stiffness and [cardiovascular disease] risk in patients,” they added.
The study, however, did not address particular exercises. Rather, the team recommended further studies to “analyze the effect of exercise improving cardiorespiratory fitness upon cardiovascular disease risk in [ankylosing spondylitis].”