Descriptives.

<div><p>Background</p><p>Hypertension (HTN) is linked to an enhanced risk of chronic kidney disease and cardiovascular disease. While sodium and potassium intake affect blood pressure (BP) control, the urine sodium-to-potassium (Na/K) ratio, which reflects dietary balance and renal regulation of these electrolytes, could be associated with BP. This study aimed to evaluate the independent association between urine Na/K and uncontrolled HTN.</p><p>Methods</p><p>Data were collected from the Korea National Health and Nutrition Examination Survey from 2016 to 2021. A total of 5,770 participants diagnosed with HTN were enrolled in this study. Uncontrolled HTN was characterized by a systolic blood pressure (SBP) ≥ 140 mmHg or diastolic blood pressure (DBP) ≥ 90 mmHg. Logistic regression analysis was used to assess the relationship between urine Na/K and the risk of uncontrolled HTN.</p><p>Results</p><p>The urine Na/K was positively correlated with both SBP and mean arterial pressure. Higher urine Na/K was significantly associated with an increased risk of uncontrolled HTN using both continuous (odds ratio [95% confidence interval] 1.13 [1.09–1.16], P <0.01]) and across quartile values (with Q1 as a reference; Q2: 1.26 [1.06–1.49], P = 0.01; Q3: 1.50 [1.27–1.78], P <0.01; Q4: 1.85 [1.55–2.17], P < 0.01). The subgroup analysis also showed that higher urine Na/K were significantly related to the risk of uncontrolled HTN in the presence of proteinuria or CKD.</p><p>Conclusion</p><p>Urine Na/K ratio is independently associated with uncontrolled HTN in the general population and in patients with CKD. Our findings suggest that monitoring the urine Na/K could serve as an effective tool for identifying subjects at risk of uncontrolled HTN.</p></div>