The relationship of blood volume (BV) to systemic blood pressure (BP) is not well defined in resistant hypertension (RH). The goal of this study was to examine the extent to which systemic BP stratified by patient sex would impact BV phenotypes. A retrospective analysis of clinical and quantitative BV data was undertaken in a cohort of ambulatory patients with a history of controlled and uncontrolled RH. We analyzed 253 unique BVs with 54% of patients above goal BP of <150 mmHg. BV phenotypes were highly variable but no correlation of systolic BP to absolute BV or percentage deviation from normal volume was identified in either sex. Males demonstrated overall larger absolute BVs with higher prevalence of large plasma volume (PV) expansion; females were overall more hypovolemic by total BV but with a higher frequency of normal PV than males. Females trended towards more RBC mass deficit (true anemia) (49% vs. 38%. P = 0.084) while more males demonstrated RBC mass excess (erythrocythemia) (21% vs. 11%, P = 0.029). Importantly, a significant portion (52%) of patients with true anemia identified by BVA would go undetected by hemoglobin measurement alone. BV phenotypes are highly diverse in patients with RH. However, absolute BV or variability in BV phenotypes even when stratified by patient sex did not demonstrate an association with systemic BP. BV phenotyping provides a key to optimizing clinical management by identifying RBC mass profiles particularly distinguishing true anemia, dilutional anemia, and erythrocythemia and the contribution of PV expansion. Findings support the clinical utility of BV phenotyping in RH.

中文翻译：

---

难治性高血压的血容量表型和患者性别。

难治性高血压 (RH) 中血容量 (BV) 与全身血压 (BP) 的关系尚未明确定义。本研究的目的是检查按患者性别分层的全身血压对 BV 表型的影响程度。对一组具有受控和不受控 RH 病史的门诊患者进行临床和定量 BV 数据的回顾性分析。我们分析了 253 例独特的 BV，其中 54% 的患者血压高于目标血压 (<150 mmHg)。 BV 表型变化很大，但在任一性别中均未发现收缩压与绝对 BV 或偏离正常容量的百分比之间的相关性。男性表现出总体上更大的绝对 BV，且血浆容量 (PV) 扩张的发生率更高；总体而言，女性的总 BV 血容量较低，但正常 PV 的频率高于男性。女性倾向于更多的红细胞质量赤字（真性贫血）（49% vs. 38%，P = 0.084），而更多的男性则表现出红细胞质量过剩（红细胞增多症）（21% vs. 11%，P = 0.029）。重要的是，通过 BVA 识别出的真正贫血患者中，有很大一部分 (52%) 仅通过血红蛋白测量无法检测到。 RH 患者的 BV 表型高度多样化。然而，即使按患者性别分层，绝对 BV 或 BV 表型变异也未证明与全身血压存在关联。 BV 表型分析通过识别红细胞质量特征，特别是区分真性贫血、稀释性贫血和红细胞增多症以及 PV 扩张的贡献，为优化临床管理提供了关键。研究结果支持 BV 表型分析在 RH 中的临床实用性。