Wan George J, Zhang Huabin F, Tedeschi Michael A, Hackett David
Wyeth Research, Collegeville, USA.
Curr Med Res Opin. 2006 Mar;22(3):587-91. doi: 10.1185/030079906X96245.
The efficacy of treatments for generalized anxiety disorder has usually been measured in terms of response or remission of symptoms. These endpoints, however, may not adequately capture the transient periods of symptom abatement and relapse characteristic of chronic psychiatric disorders. Here, we evaluate the measurement of treatment effectiveness in terms of the number of symptom-free days (SFDs).
A pooled analysis was performed of data from five manufacturer-initiated trials of venlafaxine extended-release (XR) in patients with generalized anxiety disorder without co-morbid major depressive disorder. The trials were randomized, double-blind, placebo-controlled and of 8 weeks duration (total intent-to-treat population 1295 venlafaxine XR, 544 placebo). Two of the studies had extensions up to 6 months (intent-to-treat population 514 venlafaxine XR, 253 placebo). The patients were >or= 18 years of age with a Hamilton Rating Scale for Anxiety (HAM-A) score of >or= 18.
SFDs were estimated using weekly scores on the HAM-A. Values of 7 and 0 SFDs, respectively, were assigned to each week the patient had a HAM-A score of <or= 7 (the remission threshold) and >or= 18 (the minimum threshold for anxiety). Fractional SFD values were assigned proportionately to weekly HAM-A scores between 7 and 18.
The median (inter-quartile range) SFDs were 19 (2-36) for venlafaxine XR and 10 (0-27) for placebo in the 8-week studies (p < 0.0001). In the 6-month extension studies the SFDs were 102 (27-139) for venlafaxine XR and 36 (0-94) for placebo (p < 0.0001).
SFDs differentiate between active treatment and placebo in clinical trials and may be an appropriate measure of treatment effectiveness.
广泛性焦虑症治疗效果通常依据症状的缓解或减轻来衡量。然而，这些终点可能无法充分体现慢性精神疾病症状减轻和复发的短暂阶段。在此，我们依据无症状天数（SFDs）评估治疗效果的衡量指标。
对五项由生产商发起的针对无共病重度抑郁症的广泛性焦虑症患者的文拉法辛缓释剂（XR）试验数据进行汇总分析。这些试验为随机、双盲、安慰剂对照，为期8周（意向性治疗总人群：文拉法辛XR组1295例，安慰剂组544例）。其中两项研究延长至6个月（意向性治疗人群：文拉法辛XR组514例，安慰剂组253例）。患者年龄≥18岁，汉密尔顿焦虑量表（HAM - A）评分≥18分。
使用HAM - A的每周评分估算SFDs。患者HAM - A评分为≤7分（缓解阈值）和≥18分（焦虑最低阈值）的每周分别赋值为7和0个SFDs。分数SFD值按比例分配给7至18分之间的每周HAM - A评分。
在8周研究中，文拉法辛XR组的SFDs中位数（四分位间距）为19（2 - 36），安慰剂组为10（0 - 27）（p < 0.0001）。在6个月的延长研究中，文拉法辛XR组的SFDs为102（27 - 139），安慰剂组为36（0 - 94）（p < 0.0001）。
在临床试验中，SFDs可区分活性治疗和安慰剂，可能是衡量治疗效果的合适指标。
