Rockwood Kenneth, Fay Sherri, Song Xiaowei, MacKnight Chris, Gorman Mary
Division of Geriatric Medicine, Dalhousie University, Halifax, NS.
CMAJ. 2006 Apr 11;174(8):1099-105. doi: 10.1503/cmaj.051432. Epub 2006 Mar 22.
Although cholinesterase inhibitors have produced statistically significant treatment effects, their clinical meaningfulness in Alzheimer's disease is disputed. An important aspect of clinical meaningfulness is the extent to which an intervention meets the goals of treatment.
In this randomized controlled trial, patients with mild to moderate Alzheimer's disease were treated with either galantamine or placebo for 4 months, followed by a 4-month open-label extension during which all patients received galantamine. The primary outcome measures were Goal Attainment Scaling (GAS) scores from assessments by clinicians and by patients or caregivers of treatment goals set before treatment and evaluated every 2 months. Secondary outcome measures included the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-cog), the Clinician's Interview-based Impression of Change plus Caregiver Input (CIBIC-plus), the Disability Assessment for Dementia (DAD) and the Caregiving Burden Scale (CBS). To evaluate treatment effect, we calculated effect sizes (as standardized response means [SRMs]) and p values.
Of 159 patients screened, 130 (mean age 77 [standard deviation (SD) 7.7]; 63% women) were enrolled in the study (64 in the galantamine group and 66 in the placebo group); 128 were included in the analysis because they had at least one post-baseline evaluation. In the intention-to-treat analysis, the clinician-rated GAS scores showed a significantly greater improvement in goal attainment among patients in the galantamine group than among those in the placebo group (change from baseline score 4.8 [SD 9.6]) v. 0.9 [SD 9.5] respectively; SRM = 0.41, p = 0.02). The patient- caregiver-rated GAS scores showed a similar improvement in the galantamine group (change from baseline score 4.2 [SD 10.6]); however, because of the improvement also seen in the placebo group (2.3 [SD 9.0]), the difference between groups was not statistically significant (SRM = 0.20, p = 0.27). Of the secondary outcome measures, the ADAS-cog scores differed significantly between groups (SRM = -0.36, p = 0.04), as did the CIBIC-plus scores (SRM = -0.40, p = 0.03); no significant differences were in either the DAD scores (SRM = 0.28, p = 0.13) or the CBS scores (SRM = -0.17, p = 0.38).
Clinicians, but not patients and caregivers, observed a significantly greater improvement in goal attainment among patients with mild to moderate Alzheimer's disease who were taking galantamine than among those who were taking placebo.
尽管胆碱酯酶抑制剂已产生具有统计学意义的治疗效果,但其在阿尔茨海默病中的临床意义仍存在争议。临床意义的一个重要方面是干预措施达到治疗目标的程度。
在这项随机对照试验中,轻度至中度阿尔茨海默病患者接受加兰他敏或安慰剂治疗4个月,随后进行为期4个月的开放标签延长期,在此期间所有患者均接受加兰他敏治疗。主要结局指标是目标达成量表(GAS)评分,该评分来自临床医生以及患者或护理人员对治疗前设定并每2个月评估一次的治疗目标的评估。次要结局指标包括阿尔茨海默病评估量表认知分量表(ADAS-cog)、基于临床医生访谈的变化印象加护理人员意见(CIBIC-plus)、痴呆症残疾评估(DAD)和护理负担量表(CBS)。为评估治疗效果,我们计算了效应量(作为标准化反应均值[SRMs])和p值。
在159名筛查的患者中,130名(平均年龄77岁[标准差(SD)7.7];63%为女性)被纳入研究(加兰他敏组64名,安慰剂组66名);128名被纳入分析,因为他们至少有一次基线后评估。在意向性分析中,临床医生评定的GAS评分显示,加兰他敏组患者在目标达成方面的改善明显大于安慰剂组患者(从基线评分的变化分别为4.8[SD 9.6]和0.9[SD 9.5];SRM = 0.41,p = 0.02)。患者-护理人员评定的GAS评分显示加兰他敏组有类似改善(从基线评分的变化为4.2[SD 10.6]);然而,由于安慰剂组也有改善(2.3[SD 9.0]),两组之间的差异无统计学意义(SRM = 0.20,p = 0.27)。在次要结局指标中,ADAS-cog评分在两组之间有显著差异(SRM = -0.36,p = 0.04),CIBIC-plus评分也是如此(SRM = -0.40,p = 0.03);DAD评分(SRM = 0.28,p = 0.13)或CBS评分(SRM = -0.17,p = 0.38)均无显著差异。
临床医生观察到,服用加兰他敏的轻度至中度阿尔茨海默病患者在目标达成方面的改善明显大于服用安慰剂的患者,但患者和护理人员未观察到这一点。