Campbell N R, Hull R D, Brant R, Hogan D B, Pineo G F, Raskob G E
Department of Medicine, Faculty of Medicine, University of Calgary, Alberta.
Arch Intern Med. 1996 Apr 22;156(8):857-60.
Many studies have suggested that elderly patients are at increased risk of bleeding during heparin therapy.
To establish whether the risk of bleeding in the elderly results from concomitant risk factors or is associated with the aging process itself.
One hundred ninety-nine patients who presented with proximal deep vein thrombosis were treated with a standard intravenous heparin protocol in a double-blind, randomized, prospective study. Bleeding complications were monitored. Activated partial thromboplastin times and heparin levels were assessed 4 to 6 hours after a standard intravenous heparin bolus and infusion. Heparin doses and heparin levels were also assessed after stable therapeutic heparin infusion rates were established.
There was an increase in total and major bleeding complications with aging (P < .05) that was not accounted for by standard risk factors for bleeding. Aging was associated with an increase in heparin levels (r = .239, P = .003) and a tendency for an increase in activated partial thromboplastin time (r = .134, P = .07) after standard heparin doses. Aging was also associated with lower heparin dose requirements (r = .267, P = .003) after therapeutic activated partial thromboplastin times were achieved.
Aging is a risk for heparin-related bleeding that may be explicable by age-related changes in the pharmacologic characteristics of heparin.
许多研究表明，老年患者在肝素治疗期间出血风险增加。
确定老年患者出血风险是由伴随的风险因素导致，还是与衰老过程本身有关。
在一项双盲、随机、前瞻性研究中，对199例近端深静脉血栓形成患者采用标准静脉肝素方案进行治疗。监测出血并发症。在标准静脉注射肝素推注和输注后4至6小时评估活化部分凝血活酶时间和肝素水平。在确定稳定的治疗性肝素输注速率后，也评估肝素剂量和肝素水平。
随着年龄增长，总出血并发症和严重出血并发症均增加（P < .05），这并非由标准出血风险因素所致。年龄增长与标准肝素剂量后肝素水平升高（r = .239，P = .003）以及活化部分凝血活酶时间有增加趋势（r = .134，P = .07）相关。在达到治疗性活化部分凝血活酶时间后，年龄增长还与较低的肝素剂量需求相关（r = .267，P = .003）。
衰老与肝素相关出血风险有关，这可能可通过肝素药理学特性的年龄相关变化来解释。
