de Souza Fabio, Muxfeldt Elizabeth S, Margallo Victor, Cortez Arthur F, Cavalcanti Aline H, Salles Gil F
Hypertension Program, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
J Hypertens. 2017 Apr;35(4):837-844. doi: 10.1097/HJH.0000000000001254.
Aldosterone excess has been equally associated with resistant hypertension (RHT) and obstructive sleep apnoea (OSA). We conducted a randomized controlled study to assess the effect of continuous positive airway pressure (CPAP) treatment on 24-h urinary aldosterone excretion in patients with RHT and moderate/severe OSA.
A total of 117 patients were randomized (57 CPAP and 60 control groups). Aldosterone excretion was determined by 24 h urine (24h-UAldo) collected at randomization and after 6 months of follow-up. Twenty-four hour UAldo differences were assessed by general linear model with the allocation group (CPAP or control) as a fixed factor adjusted for their respective baseline values. Both intention-to-treat and per-protocol (45 patients with optimal adherence to CPAP) analyses were performed.
Baseline 24h-UAldo was higher in severe OSA than in moderate OSA patients. After CPAP treatment, there was a borderline significant reduction in 24h-UAldo [mean difference: -2.5 μg/24 h; 95% confidence interval (95% CI): -5.3 to +0.3 μg/24 h; P = 0.07] in intention-to-treat analysis, whereas in the per-protocol analysis, the CPAP group had a greater reduction in 24h-UAldo than the control group (mean difference: -3.3 μg/24 h; 95% CI: -6.1 to -0.4 μg/24 h; P = 0.027). This effect occurred solely in patients with uncontrolled ambulatory BPs, and was more pronounced in those with the nondipping pattern, not using spironolactone, less obese, and with lowest sleep SaO2 levels.
Only optimal CPAP treatment reduced aldosterone excretion in patients with uncontrolled RHT, while on intention-to-treat the effect was borderline. Although nondefinitive, our results suggest that CPAP treatment might improve cardiovascular outcomes by reducing aldosterone excess in resistant hypertensive individuals with OSA.
ClinicalTrials.gov Identifier: NCT01508754.
醛固酮过多与顽固性高血压（RHT）及阻塞性睡眠呼吸暂停（OSA）均相关。我们开展了一项随机对照研究，以评估持续气道正压通气（CPAP）治疗对RHT合并中度/重度OSA患者24小时尿醛固酮排泄的影响。
共117例患者被随机分组（57例CPAP组和60例对照组）。在随机分组时及随访6个月后，通过收集24小时尿液（24h-UAldo）来测定醛固酮排泄。采用一般线性模型评估24小时UAldo的差异，将分组（CPAP或对照组）作为固定因素，并根据各自的基线值进行调整。进行了意向性分析和符合方案分析（45例最佳依从CPAP治疗的患者）。
重度OSA患者的基线24h-UAldo高于中度OSA患者。在CPAP治疗后，意向性分析中24h-UAldo有临界显著降低[平均差异：-2.5μg/24h；95%置信区间（95%CI）：-5.3至+0.3μg/24h；P = 0.07]，而在符合方案分析中，CPAP组的24h-UAldo降低幅度大于对照组（平均差异：-3.3μg/24h；95%CI：-6.1至-0.4μg/24h；P = 0.027）。这种效应仅发生在动态血压未得到控制的患者中，在非勺型血压模式、未使用螺内酯、肥胖程度较低且睡眠期间最低血氧饱和度水平最低的患者中更为明显。
仅最佳CPAP治疗可降低未控制的RHT患者的醛固酮排泄，而在意向性分析中该效应处于临界状态。尽管结果不明确，但我们的研究结果表明，CPAP治疗可能通过减少合并OSA的顽固性高血压个体的醛固酮过多来改善心血管结局。
ClinicalTrials.gov标识符：NCT01508754。
