Kidney Week

Abstract: SA-PO0510

Directly Measured Urinary Sodium and Blood Pressure in Korean Patients with CKD: The K-SALT Study

Session Information

• CKD: Clinical - Therapies, CKM Health, Special Populations, and More
  October 24, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: CKD (Non-Dialysis)

• 2202 CKD (Non-Dialysis): Clinical, Outcomes, and Trials

Authors

• Choi, Ji-Young, Kyungpook National University School of Medicine, Daegu, Korea (the Republic of)

Ji-Young Choi, MD, PhD

• Cho, Semin, Chung-Ang University College of Medicine, Dongjak-gu, Seoul, Korea (the Republic of)

Semin Cho, MD

• Park, Hayne C., Hallym University Kangnam Sacred Heart Hospital, Yeongdeungpo-gu, Seoul, Korea (the Republic of)

Hayne C. Park, MD, PhD

• Park, Woo Yeong, Keimyung University School of Medicine, Daegu, Korea (the Republic of)

Woo Yeong Park, MD, PhD

• Kim, Seo Rin, Pusan National University School of Medicine, Busan, Korea (the Republic of)

Seo Rin Kim, MD

• Kim, Yong Chul, Seoul National University Hospital, Jongno-gu, Seoul, Korea (the Republic of)

Yong Chul Kim, MD, PhD

• Ro, Han, Truewords Dialysis Clinic, Incheon, Korea (the Republic of)

Han Ro, MD, PhD

• Park, Sihyung, Inje University Haeundae Paik Hospital, Busan, Korea (the Republic of)

Sihyung Park, MD

• Baek, Chung Hee, Asan Medical Center, Songpa-gu, Seoul, Korea (the Republic of)

Chung Hee Baek, MD

• Suh, Sang Heon, Chonnam National University Hospital, Dong-gu, Gwangju, Korea (the Republic of)

Sang Heon Suh, MD, PhD

• Ahn, Shin-Young, Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do, Korea (the Republic of)

Shin-Young Ahn, MD, PhD

• An, Jung Nam, Hallym University Sacred Heart Hospital, Anyang-si, Gyeonggi-do, Korea (the Republic of)

Jung Nam An, MD, PhD

• Lee, Jangwook, Dongguk University Ilsan Hospital, Goyang-si, Gyeonggi-do, Korea (the Republic of)

Jangwook Lee, MD

• Lee, Chungsik, Cheju Halla General Hospital, Jeju-si, Jeju-do, Korea (the Republic of)

Chungsik Lee, MD, PhD

• Lee, Haekyung, Soonchunhyang University Hospital, Yongsan-gu, Seoul, Korea (the Republic of)

Haekyung Lee, MD

• Cho, Hyunjeong, Chungbuk National University Hospital, Cheongju-si, Chungcheongbuk-do, Korea (the Republic of)

Hyunjeong Cho, MD

• Hwang, Seon Deok, Inha University Hospital, Incheon, Korea (the Republic of)

Seon Deok Hwang, MD

• Hwang, Jin Ho, Chung Ang University Hospital, Dongjak-gu, Seoul, Korea (the Republic of)

Jin Ho Hwang, MD, PhD

• Park, Ji In, Kangwon National University Hospital, Chuncheon-si, Gangwon-do, Korea (the Republic of)

Ji In Park, MD

• Park, Hyeong cheon, Gangnam Severance Hospital, Seoul, Korea (the Republic of)

Hyeong cheon Park, MD, PhD

• Jung, Ji Yong, Gachon University Gil Medical Center, Namdong-gu, Incheon, Korea (the Republic of)

Ji Yong Jung, MD, PhD

Background

Higher sodium intake is associated with elevated blood pressure (BP) and increased cardiovascular risk. The associations of measured 24-hour urinary sodium excretion and sodium-to-potassium (Na/K) ratio with BP in Korean patients with CKD remain unclear.

Methods

We analyzed 1,054 patients with CKD from the K-SALT study, a multicenter cohort with directly measured 24-hour urinary sodium and potassium excretion conducted at 16 tertiary teaching hospitals in South Korea (June 2024 to September 2025). Associations of urinary sodium excretion and Na/K ratio with systolic BP (SBP) and diastolic BP (DBP) were evaluated using multivariable linear regression, spline, and subgroup analyses.

Results

The mean age was 59.3 ± 15.2 years, and 63.1% were male. In multivariable analyses, each 100 mmol/day increase in 24-hour urinary sodium excretion was associated with a 1.65 mmHg higher SBP (95% CI, 0.22–3.08; p = 0.024), representing a modest but clinically relevant increase at the population level. Each 1-unit increase in Na/K ratio was associated with a 0.63 mmHg higher SBP (95% CI, 0.03–1.22; p = 0.038), whereas no significant associations were observed with DBP. Spline analyses demonstrated a linear increase in SBP without a clear threshold. The association between urinary sodium excretion and SBP was more pronounced in younger participants (<60 years), those with CKD stage 1, preserved kidney function (eGFR ≥60 mL/min/1.73 m2), and those not receiving sodium–glucose cotransporter-2 inhibitors.

Conclusion

Higher 24-hour urinary sodium excretion and Na/K ratio were independently associated with higher SBP in Korean patients with CKD. These findings support the importance of dietary sodium reduction and the use of urinary sodium assessment for BP management in CKD.