Circadian phenotypes and arterial stiffness in resistant hypertension: a multicenter observational analysis using abpm and pwv

Abstract Background Resistant Hypertension (RHT) is a condition associated with high cardiovascular risk despite optimal antihypertensive therapy. Ambulatory blood pressure monitoring (ABPM) remains the gold standard which provides essential information related to the response of the treatment besides the circadian blood pressure patterns. Meanwhile, the use of pulse wave velocity (PWV) and augmentation index (AIx@75) offer insight into subclinical arterial stiffness, mainly in a population with different patterns of hemodynamics profiles. There are no published data in Latin America assessing on these combined measures in RHT. Objective To characterize circadian blood pressure patterns and arterial stiffness in patients with RHT using 24-hour ABPM in all participants and PWV/AIx@75 in a representative subgroup, across multiple specialized centers. Methods This multicenter observational study, led by the Hypertension and Vascular Mechanics Laboratory of the Instituto Cardiovascular de Quito, included 120 patients with confirmed RHT from four centers in Quito. All patients underwent 24-hour ABPM, and a subgroup of 38 also underwent PWV and AIx@75 measurement. Demographic, hemodynamic, and pharmacological characteristics were collected according to the 2025 ESC/ESH hypertension guidelines. Results The mean age of the study population was 70.2 ± 13.3 years, with a female predominance (69.5%). Mean 24-hour systolic and diastolic blood pressure (SBP/DBP) were 121.9 and 69 mmHg, respectively. The average 24-hour pulse pressure was 52.9 ± 9.7 mmHg. Based on the ABPM, circadian patterns were distributed as follows: Dipper: 39%; Non dipper: 41%; and Riser: 20%. In the subgroup with arterial stiffness data (n=38), the mean PWV was 10.3 ± 2.2 m/s and the AIx@75 was 20.5 ± 10.3%. Both variables followed a normal distribution according to the Shapiro-Wilk test (W = 0.974, p = 0.528 and W = 0.959, p = 0.179; respectively). Concerning pharmacological therapy, the entire cohort received combination therapy and the mean number of antihypertensive drugs per patient was 4.35. Conclusion This first Ecuadorian multicenter study shows that ABPM revealed a high prevalence of altered circadian patterns and elevated pulse pressure despite optimal therapy. The PWV data confirmed subclinical arterial stiffness in a substantial proportion of patients. According to these findings the integration of hemodynamic phenotyping in the routine evaluation of RHT is supported and highlight the importance of ABPM and PWV even in resource-limited settings.Table 1(part 1)For image description, please refer to the figure legend and surrounding text. Table 1(part 2)For image description, please refer to the figure legend and surrounding text.