Importance Coronary artery calcification (CAC) is highly prevalent in patients with pre-dialysis chronic kidney disease (CKD). However, there are sparse data on the association of CAC with subsequent risk of cardiovascular disease (CVD) and all-cause mortality in this population. Objectives To study the prospective association of CAC with risk of CVD and all-cause mortality among patients with pre-dialysis CKD. Design, Setting, and Participants Chronic Renal Insufficiency Cohort study recruited adults aged 21–74 years with an estimated-glomerular filtration rate (eGFR) of 20–70 mL/min/1.73 m2 from seven clinical centers in the US. Of them, 1,541 participants without CVD at baseline who had CAC measures were included in current analyses. Exposure CAC was assessed by electron-beam computed tomography or multi-detector computed tomography. Main Outcomes and Measures Incidence of CVD (including myocardial infarction, heart failure, and stroke) and all-cause mortality were reported every six months and confirmed by medical record adjudication. Results During an average of 5.9 years of follow-up, we observed 188 CVD (60 myocardial infarction, 120 heart failure, and 27 stroke) and 137 deaths. In Cox proportional hazards models adjusted for age, gender, race, clinical site, education, physical activity, total cholesterol, HDL-cholesterol, systolic blood pressure, antihypertensive treatment, current cigarette smoking, diabetes, body-mass index, C-reactive protein, hemoglobin A1c, phosphate, troponin T, log-N-terminal pro-B-type natriuretic peptide, fibroblast growth factor-23, eGFR, and proteinuria, the hazard ratios (95% confidence interval [CI]) associated with one standard deviation of CAC were 1.40 (1.16 to 1.69, p<.001) for CVD, 1.44 (1.02 to 2.02, p=.04) for myocardial infarction, 1.39 (1.10 to 1.76, p=.006) for heart failure, and 1.19 (0.94 to 1.51, p=.15) for all-cause mortality. In addition, inclusion of CAC score led to significant increase in c-statistic 0.02 (95% CI 0.00 to 0.09, p<.001) for predicting CVD over all above-mentioned established and novel CVD risk factors. Conclusion and Relevance CAC is independently and significantly related to the risks of CVD, myocardial infarction, and heart failure in CKD patients. In addition, CAC improves risk prediction for CVD, myocardial infarction, and heart failure over established and novel CVD risk factors among CKD patients, although the change in c-statistics is small.

CKD is a major risk factor for ESRD, cardiovascular disease, and premature death. Whether dietary sodium and potassium intake affect CKD progression remains unclear. We prospectively studied the association of urinary sodium and potassium excretion with CKD progression and all-cause mortality among 3939 patients with CKD in the Chronic Renal Insufficiency Cohort Study. Urinary sodium and potassium excretion were measured using three 24-hour urine specimens, and CKD progression was defined as incident ESRD or halving of eGFR. During follow-up, 939 CKD progression events and 540 deaths occurred. Compared with the lowest quartile of urinary sodium excretion (,116.8 mmol/24 h), hazard ratios (95% confidence intervals) for the highest quartile of urinary sodium excretion ($194.6 mmol/24 h) were 1.54 (1.23 to 1.92) for CKD progression, 1.45 (1.08 to 1.95) for all-cause mortality, and 1.43 (1.18 to 1.73) for the composite outcome of CKD progression and all-cause mortality after adjusting for multiple covariates, including baseline eGFR. Additionally, compared with the lowest quartile of urinary potassium excretion (,39.4 mmol/24 h), hazard ratios for the highest quartile of urinary potassium excretion ($67.1 mmol/24 h) were 1.59 (1.25 to 2.03) for CKD progression, 0.98 (0.71 to 1.35) for all-cause mortality, and 1.42 (1.15 to 1.74) for the composite outcome. These data indicate that high urinary sodium and potassium excretion are associated with increased risk of CKD progression. Clinical trials are warranted to test the effect of sodium and potassium reduction on CKD progression.

Background In general populations, healthy lifestyle is associated with fewer adverse outcomes. We estimated the degree to which adherence to a healthy lifestyle decreases the risk of renal and cardiovascular events among adults with chronic kidney disease (CKD). Study Design Prospective cohort. Setting & Participants 3006 adults enrolled in the Chronic Renal Insufficiency Cohort (CRIC) Study. Predictors Four lifestyle factors (regular physical activity, body mass index [BMI] 20–<25 kg/m2, nonsmoking, and “healthy diet”), individually and in combination. Outcomes CKD progression (50% decrease in estimated glomerular filtration rate or end-stage renal disease), atherosclerotic events (myocardial infarction, stroke, or peripheral arterial disease), and all-cause mortality. Measurements Multivariable-adjusted Cox proportional hazards. Results During median follow-up of 4 years, we observed 726 CKD progression events, 353 atherosclerotic events, and 437 deaths. BMI ≥ 25 kg/m2 and nonsmoking were associated with reduced risk of CKD progression (HRs of 0.75 [95% CI, 0.58–0.97] and 0.61 [95% CI, 0.45–0.82] for BMIs of 25–<30 and ≥30, respectively, vs. 20–<25 kg/m2; HR for nonsmoking of 0.68 [95% CI, 0.55–0.84] compared to current smoker reference group) and reduced risk of atherosclerotic events (HRs of 0.67 [95% CI, 0.46–0.96] for BMI 25–<30 vs. 20–<25 kg/m2 and 0.55 [95% CI, 0.40–0.75] vs. current smoker). Factors associated with reduced all-cause mortality were regular physical activity (HR, 0.64 [95% CI, 0.52–0.79] vs. inactive), BMI ≥30 kg/m2 (HR, 0.64 [95% CI, 0.43–0.96] vs. 20–<25 kg/m2) and nonsmoking (HR, 0.45 [95% CI, 0.34–0.60] vs. current smoker). BMI <20 kg/m2 was associated with increased all-cause mortality risk (HR, 2.11 [95% CI, 1.13–3.93] vs. 20–25 kg/m2). Adherence to all four lifestyle factors was associated with 68% lower risk of all-cause mortality compared to adherence to no lifestyle factors (HR, 0.32; 95% CI, 0.11–0.89). Limitations Lifestyle factors were only measured once. Conclusions Regular physical activity, nonsmoking, and BMI ≥25 kg/m2 were associated with lower risk of adverse outcomes in this cohort of individuals with CKD.

Background and objectives Low health-related quality of life is associated with increased mortality in patients with ESRD. However, little is known about demographic and clinical factors associated with health-related quality of life or its effect on outcomes in adults with CKD.Design, settings, participants, & measurements Data from 3837 adult participants with mild to severe CKD enrolled in the prospective observational Chronic Renal Insufficiency Cohort and Hispanic Chronic Renal Insufficiency Cohort Studies were analyzed. Health-related quality of life was assessed at baseline with the Kidney Disease Quality of Life-36 and its five subscales: mental component summary, physical component summary, burden of kidney disease (burden), effects of kidney disease (effects), and symptoms and problems of kidney disease (symptoms). Low health-related quality of life was defined as baseline score .1 SD below the mean. Using Cox proportional hazards analysis, the relationships between low health-related quality of life and the following outcomes were examined: (1) CKD progression (50% eGFR loss or incident ESRD), (2) incident cardiovascular events, and (3) all-cause death.Results Younger age, women, low education, diabetes, vascular disease, congestive heart failure, obesity, and lower eGFR were associated with low baseline health-related quality of life (P,0.05). During a median follow-up of 6.2 years, there were 1055 CKD progression events, 841 cardiovascular events, and 694 deaths. Significantly higher crude rates of CKD progression, incident cardiovascular events, and all-cause death were observed among participants with low health-related quality of life in all subscales (P,0.05). In fully adjusted models, low physical component summary, effects, and symptoms subscales were independently associated with a higher risk of incident cardiovascular events and death, whereas low mental component summary was independently associated with a higher risk of death (P,0.05). Low health-related quality of life was not associated with CKD progression.Conclusions Low health-related quality of life across several subscales was independently associated with a higher risk of incident cardiovascular events and death but not associated with CKD progression.

Registered at ClinicalTrials.gov with study number NCT01206062.