Metabolic Syndrome and Smoking Are Associated with Future Development of Advanced Chronic Kidney Disease in Older Adults

Abstract

Introduction: Metabolic syndrome (MetS) and smoking have been identified as risk factors for chronic kidney disease (CKD) in cross-sectional studies in various age groups, but longitudinal data on progression of CKD in older adults are limited. Our objectives were to examine whether MetS and its components and smoking predict the onset of CKD stage 3b (CKD-3b) in older adults. Methods: A subset of participants of the Einstein Aging Study who were free of diabetes, dementia, and CKD-3b at enrollment were included in this analysis. CKD-3b was defined as an estimated glomerular filtration rate <45 ml/min/1.73 m². Cox proportional hazards models were used in these analyses. Results: In total, 413 ≥70-year-old individuals were eligible for this study. 65.4% were female and 26.6% were black. 22.3% of the participants had MetS at baseline, 4.4% were active smokers, and 6.1% developed CKD-3b over a mean of 4 years of follow-up. MetS and smoking independently predicted incident CKD in our fully adjusted model (hazard ratio 3.65, 95% CI 1.20-10.60, p = 0.022; hazard ratio 29.69, 95% CI 4.47-197.23, p = 0.000). Conclusion: MetS and smoking are associated with an increased incidence of CKD-3b. These risk factors are modifiable, easily identified and prevented through better health care practice and early diagnosis.

Parathyroid hormone and vitamin D are associated with the risk of metabolic obesity in a middle-aged and older Korean population with preserved renal function: A cross-sectional study

“…Subjects with stage 3a (GFR 45–59 mL/min/1.73 m 2 ) have less risk of vascular complication and mortality compared with the 3b group [26]. Zammit et al suggested that MetS is associated with an increased incidence of stage 3b [27]. Kim analyzed 2,624 Korean adults aged ≥ 50 years and found that serum concentrations of 25(OH)D were significantly lower in subjects with MetS than in those without MetS [10].…”

KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors

“…Cigarette smoking is a strong, modifiable risk factor for CVD (as well as other adverse health outcomes such as lung disease and cancer); smoking may also cause direct renal damage through microvascular injury and promotion of atherosclerosis, and has been associated with CKD in the general population. 268 , 269 A recent meta-analysis based on data from nearly 5 million persons identified from 7 general population cohorts found that, compared with nonsmokers over median cohort follow-up of 4 to 16 years, current smokers had a 76% increase in the risk of ESKD (adjusted HR, 1.29 1.76 2.41 ) and past smokers had a 45% increase in risk (adjusted HR, 1.23 1.45 1.71 ). 7 After calibration to annual ESKD incidence in the US healthy population, variations in the projected 15-year and lifetime risks of ESKD based on smoking status were generated according to age, sex, and race for healthy persons (assuming age-specific GFR, urine ACR 4 mg/g [0.4 mg/mmol], SBP 120 mmHg, BMI 26 kg/m 2 , and absence of diabetes mellitus; Figures 20 and 21 ).…”

Insulin Resistance in Kidney Disease: Is There a Distinct Role Separate from That of Diabetes or Obesity

“…Considering this, there are data suggesting that the presence of obesity (BMI >30) paradoxically confers a survival advantage in ESRD rather than being a risk factor for cardiovascular disease morbidity and mortality in this population [46]. Further, there are a number of population studies that indicate that a lower BMI (<25) is a consistently strong predictor of increased mortality, a relationship that is lost at higher BMIs [47,48,49,50,51]. It is thought there may be significant residual confounding in these studies due to unmeasurable variables such as the lack of time-dependent assessment of nutritional indices, progressive malnutrition, protein energy wasting, uremic conditions, or the presence of residual renal function in the end-stage kidney that cannot be accounted for in these population-level studies.…”