Optimal blood pressure (BP) control in hypertension depends on pharmacologic therapy and dietary factors, yet the interaction between antihypertensive treatment intensity and sodium-to-potassium (Na/K) ratio remains uncertain. 

This analysis, published in the Frontiers of Cardiovascular Medicine, evaluated whether treatment strategy and Na/K ratio are associated with BP control and cardiovascular disease (CVD), and whether dietary Na/K modifies treatment effects.

Data from 4,800 treated adults with hypertension in the National Health and Nutrition Examination Survey (NHANES) 2009-2018 were analyzed. BP control was defined as <130/80 mmHg. Survey-weighted logistic models assessed associations between treatment strategy (monotherapy vs combination therapy), Na/K ratio, BP control, and CVD prevalence.
Interaction analyses were conducted on multiplicative and additive scales. Parallel mechanistic experiments were performed in human umbilical vein endothelial cells (HUVECs) exposed to normal or high Na/K conditions, angiotensin II (Ang II), and antihypertensive agents.

Combination therapy showed no significant association with BP control compared with monotherapy (odds ratio [OR] 0.89; P=0.214), but it was associated with higher CVD prevalence (OR 2.40; P<0.001). 

The Na/K ratio showed no significant association with BP control or CVD across quartiles, and no interaction with treatment strategy was observed. In vitro, high Na/K conditions exacerbated Ang II–induced endothelial injury; however, the effects of losartan and combination therapy remained comparable under both Na/K conditions.

These findings show no interaction between treatment strategy and Na/K ratio on clinical outcomes. Dietary Na/K showed no interaction with antihypertensive treatment in this population.