Kidney Week

Abstract: FR-PO446

Smoking Is a Risk Factor for the Progression of CKD: From the Korean Cohort Study for Outcome in Patients With CKD

Session Information

• CKD: Risk Factors for Incidence and Progression - II
  November 03, 2017 | Location: Hall H, Morial Convention Center
  Abstract Time: 10:00 AM - 10:00 AM

Category: Chronic Kidney Disease (Non-Dialysis)

• 301 CKD: Risk Factors for Incidence and Progression

Authors

• Choi, Arum, College of Medicine, Severance Biomedical Science Institute, Brain Korea 21 PLUS, Yonsei University, Seoul, Korea (the Republic of)

Arum Choi,

• Wu, Meiyan, College of Medicine, Severance Biomedical Science Institute, Brain Korea 21 PLUS, Yonsei University, Seoul, Korea (the Republic of)

Meiyan Wu,

• Han, Seung Hyeok, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea (the Republic of)

Seung Hyeok Han,

Background

Smoking is a risk factor of developing incident chronic kidney disease (CKD). However, most studies included relatively healthy participants without CKD and studies on the association between smoking and deterioration of kidney function in patients with CKD are scarce. Therefore, we aimed to evaluate the effect of smoking on kidney disease progression and dose-response relationship by pack-years in these patients.

Methods

The KoreaN cohort study for Outcome in patients With Chronic Kidney Disease (KNOW-CKD) is a nation-wide prospective observational cohort study from 9 centers in Korea. A total of 2218 patients were included in the final analysis. Patients were categorized into never-, former-, and current- smokers. Primary outcome was a composite of a reduction of eGFR of ≥ 50%, initiation of dialysis, or kidney transplantation.

Results

The mean age was 53.6±12.3 years and 1356 patients (61.1%) were male. Compared to never-smokers, former- or current- smokers had higher prevalence of diabetes (38.4% vs. 29.6%, P < 0.001) and cardiovascular disease (14.3% vs. 7.8%, P < 0.001) at baseline. In addition, these patients had higher blood pressure (128.9±16.7 vs. 127.0±15.8 mmHg, P = 0.007), lower eGFR (48.6±27.9 vs. 52.2±32.2 ml/min/1.73m², P = 0.004) and higher level of proteinuria [1.6 (0.2-1.8) vs. 1.2 (0.1-1.2) g/day, P < 0.001] than never-smokers. During a mean follow-up duration of 36.7±18.2 months, primary outcome occurred in 168 (16.5%) in former- or current-smokers as compared to 164 (13.6%) in never-smokers (P = 0.057). In a multivariable Cox regression analysis after adjustment of confounding factors, smokers were significantly associated with an increased risk of primary outcome (HR, 1.36; 95% CI, 1.05-1.77; P = 0.020). In addition, HRs for primary outcome were 0.94 (95% CI, 0.65-1.35; P = 0.723), 1.49 (95% CI, 1.04-2.14; P = 0.030), 1.83 (95% CI, 1.12-2.86; P = 0.008), and 2.21 (95% CI, 1.39-3.51; P = 0.001) for <14.9, 15-29.9, 30-44.4 and ≥45 pack-years, respectively, suggesting that there was a dose-response relationship between smoking consumption and CKD progression.

Conclusion

This study clearly showed that smoking is associated with deterioration of kidney disease. Thus, quitting smoking should be a part of preventative strategy in management of CKD.