Study Recommends Rate of Physical Activity for Patients With CKD

Higher levels of physical activity are associated with reduced risk of heart problems and increased survival for patients suffering with chronic kidney disease (CKD), according to a new study released Thursday.

The report, published on World Kidney Day in the European Journal of Preventive Cardiology, is the first to report the optimal amount of activity in these patients, according to the authors.

World Health Organization guidelines recommend a minimum of 150 minutes of moderate activity (such as walking) or 75 minutes of vigorous activity (such as jogging), which translates into 7.5 metabolic equivalent hours per week (MET‑h/week). The results of the study found that an increase of activity to the WHO minimum to as high as twice that level was associated with longer survival and decreased risk of end stage renal disease (ESRD) and major cardiovascular events. Remaining active was crucial to sustaining the benefits.

“Our results suggest that physical activity should be integrated into the clinical care of patients with kidney disease,” said author Der-Cherng Tarng, MD, PhD, of Taipei Veterans General Hospital and National Yang-Ming University in Taiwan.

Patients should not exceed activity beyond twice the WHO minimum due to increased risk of heart-related events, the authors said. That finding, which runs contrary to recommendations for the general population, is likely due to the association between CKD and accelerated accumulation of plaque in the arteries.

“Extreme amounts of exercise can induce heart rhythm disorders [arrhythmias] in those with kidney disease,” said fellow author Wei-Cheng Tseng, MD. “It therefore seems sensible to avoid very high levels to maximize the benefits and minimize the risks.”

CKD affects approximately 700 million people worldwide. The body’s reduced ability to rid itself of toxins leads to muscle wasting and decreased physical activity. Regular physical activity reduces inflammation, plaque buildup, and deterioration of blood-vessel function. Once CKD progresses to ESRD, the risk of cardiovascular death is 10-20 times compared with the general population. Cardiovascular disease is the leading cause of death in patients with CKD and ESRD.

The study included 4508 patients with CKD between 2004 and 2017. Patients were not on dialysis. Patients were divided into 3 groups according to weekly physical activity assessed with the National Health and Nutrition Examination Survey questionnaire: highly active (WHO minimum or more), low active (less than the WHO minimum), or inactive (no activity). The intensity of a person’s physical activity type was converted a metabolic equivalent of task (MET). Follow-up was conducted every 3 months.

The researchers analyzed the association between physical activity and adverse outcomes after adjusting for other factors that could influence the relationships including age, sex, primary renal diseases, smoking, comorbidities, and other data such as body mass index, blood pressure, and medications.

Compared with the inactive group, the highly active group had a 25% lower risk of death from all causes in addition to ESRD (HR, 0.75; 95% CI 0.67-084, P <.001); the low active group did not have a statistically significant reduction.

The highly active group had a 38% lower risk of death when excluding ESRD (HR, 0.62; 95% CI, 0.53-0.74, P <.001), a 17% lower risk of ESRD (HR, 0.83; 95% CI, 0.72-0.96), P <.001), and a 37% lower risk of a major cardiac event (HR, 0.63; 95% CI, 0.51-0.76, P <.001).

Patients who switched from being highly active to less active saw increased risks for all-cause mortality in addition to ESRD (HR 1.39; 95% CI, 1.06–1.82; P = .017), all-cause mortality excluding (HR, 2.20; 95% CI, 1.55-3.13; P < .001), and major cardiac event (HR, 2.04, 95% CI, 1.32–3.14; P = .001) compared with those who were continually highly active.

Reference

Kuo C-P, Tsai M-T, Lee K-H, et al. Dose–response effects of physical activity on all-cause mortality and major cardiorenal outcomes in chronic kidney disease. Eur J Prev Cardiol. Published online March 10, 2021. doi:10.1093/eurjpc/zwaa162