MOVING MORE ASSOCIATES WITH REDUCED RISK OF CARDIOVASCULAR DISEASE AND DEATH ACROSS ALL STAGES OF CHRONIC KIDNEY DISEASE: A UK BIOBANK STUDY

Abstract BACKGROUND AND AIMS Physical activity (PA) is widely recommended for the prevention of chronic conditions including cardiovascular (CV) disease. In chronic kidney disease (CKD), it is unclear whether PA confers a similar benefit. We examined whether the duration and intensity of PA are associated with the risk of CV disease and mortality and whether the relationship differs in CKD. METHOD Participants were from UK Biobank: a prospective cohort study with over 500 000 participants. The estimated glomerular filtration rate was calculated using cystatin C (eGFRcys). CKD was defined according to the KDIGO guidelines and participants were categorized as no CKD (eGFRcys > 90mL/min/1.73m2), CKD G1-2 (eGFRcys 60–89mL/min/1.73m2) or CKD G3-5 (eGFRcys < 60mL/min/1.73m2). Exercise duration and intensity were self-reported using the international physical activity questionnaire (IPAQ) and participants were categorized into four groups: inactive (reference), low, moderate and vigorous PA, according to World Health Organisation (WHO) weekly PA recommendations. Cox proportional hazards models tested associations between PA category and a composite endpoint of CV disease (myocardial infarction or stroke) or all-cause mortality across CKD categories. Models were adjusted for other known risk factors for CV disease and death including age, smoking status, blood pressure, eGFRcys and albuminuria. RESULTS Of 502 460 participants in UK Biobank, 123 167 were excluded because of missing biochemistry or IPAQ data and a further 21 084 were excluded because of pre-existing CV disease: 358 209 participants were included in the analyses. Of these 182 457 (51.0%) were classed as no CKD, 162 621 (45.4%) as CKD G1-2 and 13 131 (3.7%) as CKD G3-5. A total of 48 369 (13.5%) of participants were classed as inactive and 211 591 (16.5%) as undertaking vigorous PA. In participants without CKD, any PA above inactivity was associated with a reduced risk of reaching the combined endpoint by approximately 20% (low: hazard ratio, HR 0.77, 95% confidence interval, CI 0.67–0.89; moderate: HR 0.80, 95%CI 0.70–0.91; vigorous: HR 0.81, 95%CI 0.73–0.90, P < 0.001). This relationship is maintained in CKD G1-2, but in CKD G3-5, moderate (HR 0.75, 95%CI 0.61–0.93) and vigorous (HR 0.77, CI 0.66–0.89, P < 0.001) activity are associated with reduced risk of the combined endpoint (Table 1). Interestingly across all categories of CKD, the majority of participants considered that they undertook more than the WHO minimum recommended PA per week. CONCLUSION Achieving the minimum weekly targets for PA set by WHO is associated with a significantly reduced risk of a combined endpoint of CV disease and death. This relationship is preserved in those with CKD G1-2, even when adjusted for other recognized risk factors. The benefit is seen in CKD G3-5 with increased intensity of PA, above the WHO minimum. PA data is self-reported which limits the accuracy and association does not prove causality. However, patients with CKD have a much higher risk of CVD and death and PA is a simple, low-cost intervention that warrants further study to improve CV morbidity and all-cause mortality amongst people with CKD.