Dani Krishna A, McCormick Michael T, Muir Keith W
Division of Clinical Neurosciences, University of Glasgow, Institute of Neurological Sciences, Southern General Hospital, Glasgow G51 4TF, Scotland, UK.
Stroke. 2008 Aug;39(8):2336-40. doi: 10.1161/STROKEAHA.107.507111. Epub 2008 Jun 5.
European directives and legislation in some countries forbid inclusion of subjects incapable of consent in research if recruitment of patients capable of consent will yield similar results. We compared brain lesion volumes in stroke patients deemed to have capacity to consent with those defined as incapacitated.
Data were obtained from 3 trials recruiting patients primarily with cortical stroke syndromes. Patients were recruited within 24 hours of onset and used MRI based selection or outcome criteria. Method of recruitment was recorded with stroke severity, age, and brain lesion volumes on Diffusion Weighted Imaging.
Of the 56 subjects included, 38 (68%) were recruited by assent and 18 (32%) by consent. The assent group had a median lesion volume of 18.35 cubic centimetres (cc) (interquartile range [IQR] 8.27-110.31 cc), compared to 2.79 cc (IQR 1.31-12.33 cc) when patients consented (P=0.0004). Lesions were smaller than 5 cc in 7/38 (18%) in the assent group and 11/18 (61%) in the consent group (P=0.0024). There was good correlation between neurological deficit by NIH stroke scale score and lesion volume (r=0.584, P<0.0001). Logistic regression demonstrated NIHSS or lesion volume predicted capacity to consent.
Patients with acute stroke who retain capacity to consent have significantly smaller infarct volumes than those incapable of consent, and these are frequently below the limits where measurement error significantly compromises valid use of volumetric end points. Only a small proportion of patients with capacity to consent would be eligible for, and contribute usefully to, most acute stroke trial protocols.
欧洲指令以及一些国家的立法规定，如果招募有同意能力的患者能产生相似结果，那么禁止将无同意能力的受试者纳入研究。我们比较了被认为有同意能力的中风患者与被定义为无同意能力的中风患者的脑损伤体积。
数据来自3项主要招募皮质中风综合征患者的试验。患者在发病后24小时内入组，并使用基于MRI的入选标准或结局标准。记录招募方法以及扩散加权成像上的中风严重程度、年龄和脑损伤体积。
在纳入的56名受试者中，38名（68%）通过赞同入组，18名（32%）通过同意入组。赞同组的损伤体积中位数为18.35立方厘米（cc）（四分位间距[IQR] 8.27 - 110.31 cc），而患者同意入组时为2.79 cc（IQR 1.31 - 12.33 cc）（P = 0.0004）。赞同组中7/38（18%）的损伤小于5 cc，同意组中11/18（61%）的损伤小于5 cc（P = 0.0024）。美国国立卫生研究院卒中量表评分所反映的神经功能缺损与损伤体积之间存在良好的相关性（r = 0.584，P < 0.0001）。逻辑回归表明美国国立卫生研究院卒中量表评分或损伤体积可预测同意能力。
有同意能力的急性中风患者的梗死体积明显小于无同意能力的患者，且这些梗死体积通常低于测量误差会严重影响体积终点有效使用的限度。只有一小部分有同意能力的患者符合大多数急性中风试验方案的入选标准并能做出有效贡献。
