Increased Physical Activity Linked to Lower Cardiovascular Risk in Chronic Kidney Disease

New research is underlining the importance of physical activity for extending longevity in adults with chronic kidney disease (CKD).

An analysis of data from the Chronic Renal Insufficiency Cohort (CRIC) study, results demonstrate those reporting the highest levels of physical activity had reductions in risk of 36%, 29%, and 53% for atherosclerotic events, incident heart failure, and cardiovascular mortality, respectively compared to their counterparts in the lowest quartile of physical activity.

“Our findings support that the well-established cardioprotective effects of physical activity in the general population also hold true for adults with CKD,” wrote investigators. “Consequently, our findings strengthen the evidence in support of current guideline recommendations and have important implications for clinical care, as well as future interventional studies in adults with CKD.”

Led by James P. Lash, MD, the current study was conducted on behalf of CRIC Study investigators with the intent of estimating the association between self-reported moderate-to-vigorous physical activity (MVPA) and risk of cardiovascular events and mortality. When discussing their rationale for the study design, investigators cited the reliance of CKD guidelines on data from studies based in the general population for physical activity recommendations and a dearth of studies on the topic in CKD-specific populations.

An ongoing, multicenter, observational cohort study of adults with mild-to-moderate CKD at study entry, the CRIC study provided investigators with data related to 3939 patients enrolled between May 2003 and March 2007 with a median follow-up of 13.4 years. Of the 3939 enrolled, 13 were excluded due to missing baseline data on physical activity, which resulted in a final analytical cohort of 3926 patients for the current study.

For the purpose of analysis, self-reported MVPA was categorized as quartile of MVPA and meeting the guideline-recommended level of physical activity, with classifications of active and meeting guidelines, active, but not meeting guidelines, or inactive. Specific outcomes of interest were atherosclerotic events, incident heart failure, and all-cause and cardiovascular mortality. Atherosclerotic events of interest were myocardial infarction, stroke, or peripheral artery disease (PAD). Investigators used Cox proportional hazards regression to evaluate associations between physical activity and risk of the aforementioned outcomes.

Overall, just 51% met physical activity guidelines and 30% of those not meeting goals fell into the inactive category. During the follow-up period, a total of 772 atherosclerotic events, 848 heart failure events, 1553 all-cause deaths, and 420 cardiovascular deaths occurred among the study cohort.

At baseline, compared to those within the lowest MVPA quartile, those in the highest quartile of MVPA were more likely to be younger (55.1 vs 59.5 years), male (62.8% vs 48.6%), non-Hispanic White (45.9% vs 29.3%), and have an annual household income exceeding $20,000 (62.9% vs 37.6%). Additionally, those in the lowest quartile of MVPA were more likely to have diabetes (59.0% vs 38.3%), hypertension (91.2% vs 82.1%), prevalent cardiovascular disease (43.8% vs 26.4%), and have a higher BMI (33.6 vs 31.0 kg/m2 ), higher systolic blood pressure (131 vs 126 mmHg), higher HbA1c (6.9% vs 6.4%), lower eGFR (40.1 vs 48.9 ml/min/1.73m2 ), and higher proteinuria (0.2 vs 0.1 g/g) than their counterparts in the highest quartile of MVPA.

Results of the investigators’ analysis suggested those in the highest quartile of MVPA had a lower risk of atherosclerotic events (HR, 0.64 [95% CI, 0.51-0.79]), incident heart failure (HR, 0.71 [95% CI, 0.58-0.87]), all-cause mortality (HR, 0.54 [95% CI, 0.46-0.63]), and cardiovascular mortality (HR, 0.47 [95% CI, 0.35-0.64]) compared to those in the lowest quartile of MVPA. Investigators pointed out those meeting physical activity guidelines had a lower risk of an atherosclerotic event (HR, 0.72 [95% CI, 0.61-0.85]) and a significantly lower risk of PAD (HR, 0.45 [95% CI, 0.33-0.62]) compared to those categorized as inactive.

“Our findings reinforce the importance of incorporating counseling regarding physical activity into the routine clinical care of patients with CKD. In our cohort, those in the lowest quartile of physical activity were a more vulnerable population in terms of age, socioeconomic status, and comorbidity burden,” investigators wrote. “Future work is needed to identify effective approaches to increase physical activity in this high-risk population.”

This study, “Self-reported Physical Activity and Cardiovascular Events in Adults With CKD: Findings From the CRIC (Chronic Renal Insufficiency Cohort) Study,” was published in the American Journal of Kidney Diseases.