Division of Pharmacoepidemiology and Pharmacotherapy, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3584 CA Utrecht, the Netherlands.
J Clin Epidemiol. 2010 Apr;63(4):422-7. doi: 10.1016/j.jclinepi.2009.07.001. Epub 2009 Oct 31.
When constructing drug treatment episodes using drug-dispensing databases, duration and the number of prescriptions belonging to a single treatment episode need to be defined. We investigated how different methods used to construct antidepressant treatment episodes influence their median estimated length.
A follow-up study among adult antidepressant drug users, identified from the Dutch PHARMO RLS, starting selective serotonin reuptake inhibitor (SSRI) use in 2001 was conducted. The influence of varying lengths of the prescription overlap and the gap between prescriptions (number of days or percentage of prescription duration) on the median antidepressant treatment episode length were investigated.
Of the 16,053 SSRI starters, 65.1% were female and mean age was 45.7 (SD: 17.2) years. Median antidepressant treatment episode length doubled when the gap length was expanded from 0 to 10 days. For short gap lengths the episode interquartile range was 40% to 200% larger when overlap was accounted for and when percentage of prescription duration gap length was used.
Differences in median episode length exist between methods that account for or disregard prescription overlap. These differences are of importance for studies that focus on drug exposure-outcome relationships and could have consequences for epidemiological analysis.
在使用药物配药数据库构建药物治疗期时，需要定义治疗期的持续时间和属于单个治疗期的处方数量。我们研究了使用不同方法构建抗抑郁治疗期如何影响其中位数估计长度。
对 2001 年开始使用选择性 5-羟色胺再摄取抑制剂 (SSRI) 的荷兰 PHARMO RLS 中的成年抗抑郁药物使用者进行了一项随访研究。研究了处方重叠的不同长度和处方之间的间隙（天数或处方持续时间的百分比）对中位数抗抑郁治疗期长度的影响。
在 16053 名 SSRI 启动者中，65.1%为女性，平均年龄为 45.7（SD：17.2）岁。当间隙长度从 0 扩展到 10 天时，抗抑郁治疗期长度增加了一倍。对于较短的间隙长度，当考虑到处方重叠时，治疗期四分位间距增加了 40%至 200%，而当使用处方持续时间间隙长度的百分比时，治疗期四分位间距增加了 40%至 200%。
在考虑或不考虑处方重叠的方法之间，中位数期长度存在差异。这些差异对于关注药物暴露-结果关系的研究很重要，并且可能对流行病学分析产生影响。
