Kasai Takatoshi, Bradley T Douglas, Friedman Oded, Logan Alexander G
aSleep Research Laboratories of the University Health Network Toronto Rehabilitation Institute and Toronto General Hospital bCentre for Sleep Medicine and Circadian Biology, University of Toronto cDepartment of Medicine, Mount Sinai Hospital, New York, New York, USA dProsserman Centre for Health Research, Samuel Lunenfeld Research Institute of the Mount Sinai Hospital eDepartment of Medicine, University of Toronto, Toronto, Ontario, Canada.
J Hypertens. 2014 Mar;32(3):673-80. doi: 10.1097/HJH.0000000000000047.
Fluid displacement from the lower extremities to the upper body during sleep is strongly associated with obstructive sleep apnoea in hypertensive patients. The present pathophysiological study tests the hypothesis that intensified diuretic therapy will reduce the apnoea-hypopnoea index and blood pressure of uncontrolled hypertensive patients with obstructive sleep apnoea in proportion to the reduction in overnight change in leg fluid volume.
Uncontrolled treated hypertensive patients underwent overnight polysomnography and measurement of overnight changes in leg fluid volume and neck circumference. Those with an apnoea-hypopnoea index at least 20 events per hour (n=16) received metolazone 2.5 mg and spironolactone 25 mg daily for 7 days after which the daily dose was doubled for 7 additional days. Baseline testing was again repeated.
Intensified diuretic therapy reduced the apnoea-hypopnoea index from 57.7 ± 33.0 to 48.5 ± 28.2 events per hour (P=0.005), overnight change in leg fluid volume from -418.1 ± 177.5 to -307.5 ± 161.9 ml (P<0.001) and overnight change in neck circumference from 1.2 ± 0.6 to 0.7 ± 0.4 cm (P<0.001). There was an inverse correlation between the reduction in overnight change in leg fluid volume and decrease in apnoea-hypopnoea index (r=-0.734, P=0.001). The reduction in overnight change in leg fluid volume was also significantly correlated with the change in morning blood pressure (r=0.708, P=0.002 for SBP; r=0.512, P=0.043 for DBP).
The findings provide further evidence that fluid redistribution from the legs to the neck during sleep contributes to the severity of obstructive sleep apnoea in hypertension and may be an important link between these two conditions.
睡眠期间下肢液体向上半身转移与高血压患者的阻塞性睡眠呼吸暂停密切相关。本病理生理学研究检验了这样一个假设，即强化利尿治疗将按与夜间腿部液体量变化减少的比例，降低阻塞性睡眠呼吸暂停的未控制高血压患者的呼吸暂停低通气指数和血压。
未控制的接受治疗的高血压患者接受夜间多导睡眠图检查，并测量夜间腿部液体量和颈围的变化。呼吸暂停低通气指数至少为每小时20次事件的患者（n = 16）每天接受2.5 mg美托拉宗和25 mg螺内酯治疗7天，之后每日剂量加倍再治疗7天。再次重复基线测试。
强化利尿治疗使呼吸暂停低通气指数从每小时57.7±33.0次事件降至48.5±28.2次事件（P = 0.005），夜间腿部液体量变化从 - 418.1±177.5 ml降至 - 307.5±161.9 ml（P < 0.001），夜间颈围变化从1.2±0.6 cm降至0.7±0.4 cm（P < 0.001）。夜间腿部液体量变化的减少与呼吸暂停低通气指数的降低之间存在负相关（r = - 0.734，P = 0.001）。夜间腿部液体量变化的减少也与早晨血压的变化显著相关（收缩压r = 0.708，P = 0.002；舒张压r = 0.512，P = 0.043）。
这些发现提供了进一步的证据，表明睡眠期间从腿部到颈部的液体重新分布导致高血压患者阻塞性睡眠呼吸暂停的严重程度增加，并且可能是这两种情况之间的重要联系。
