de With K, Bestehorn H, Steib-Bauert M, Kern W V
Department of Medicine, Center for Infectious Diseases and Travel Medicine, University Hospital, Hugstetter Strasse 55, Freiburg, Germany.
Infection. 2009 Aug;37(4):349-52. doi: 10.1007/s15010-008-8138-4. Epub 2009 Mar 9.
Hospital antibiotic use is usually measured by calculating the volume as the number of daily doses defined by the World Health Organization/Anatomical Therapeutic Chemical (WHO/ATC) index (DDDs) divided by a denominator indicating clinical activity, such as the number of occupied bed days. Previous studies have found discrepancies between DDDs, daily doses as recommended in practice guidelines (recommended daily doses, RDDs), and truly prescribed daily doses (PDDs). Very few studies have quantified these discrepancies.
A point prevalence survey was carried out in defined acute care service areas of a large German state university hospital. Of the 941 adult inpatients present on the day of the survey for whom adequate information was available, 267 (28%) had 471 prescriptions for antimicrobial drugs on that specific day. A check for any additional antimicrobial drug prescriptions for these 267 patients during the six days immediately preceding the survey day yielded a total of 2,304 PDDs, of which 1,754 were antibacterial agents. The latter antibacterial drug PDDs constituted the basis for analysis. The proportion of PDDs different from RDDs and from DDDs was evaluated, and the deviations were calculated. RDD dose definitions corresponded to the local practice guideline recommendations of antibiotic therapy for adult hospitalized patients with normal renal function.
Of the 1,754 PDDs, 625 were matching DDD dose definitions (36%), and 1,024 (58%) were matching RDD dose definitions (p < 0.01). Corresponding values for patients with impaired renal function (creatinine clearance < 50 ml/min) were 36% and 42%, respectively. Large DDD discrepancies (< 50% of prescribed doses matching DDD definitions) were noted for beta-lactams and macrolides, while large RDD discrepancies were observed for aminoglycosides. Compared with PDDs, the use of DDDs as the measurement of hospital antibiotic use overestimated antibiotic use volumes by 32%, while the use of RDD led to a slight underestimation (-9%).
The use of DDDs as currently defined by WHO/ATC for measuring hospital antibiotic consumption may be associated with a substantial overestimation of antibiotic use density, while using practice guideline-derived RDDs may yield more valid antibiotic exposure estimates that would be helpful in cross-sectional and longitudinal analyses of antibiotic consumption.
医院抗生素使用情况通常通过计算用量来衡量，即世界卫生组织/解剖治疗学化学分类（WHO/ATC）指数定义的每日剂量数（DDD）除以表示临床活动的分母，如占用床日数。以往研究发现DDD、实践指南中推荐的每日剂量（推荐每日剂量，RDD）与实际开具的每日剂量（PDD）之间存在差异。很少有研究对这些差异进行量化。
在德国一所大型州立大学医院的特定急性护理服务区进行了一项现患率调查。在调查当天在场且有足够信息的941名成年住院患者中，267名（28%）在该特定日期有471份抗菌药物处方。对这267名患者在调查日前六天内的任何额外抗菌药物处方进行检查，共得到2304个PDD，其中1754个为抗菌剂。后者的抗菌药物PDD构成了分析的基础。评估了与RDD和DDD不同的PDD比例，并计算了偏差。RDD剂量定义对应于当地关于肾功能正常的成年住院患者抗生素治疗的实践指南建议。
在1754个PDD中，625个符合DDD剂量定义（36%），1024个（58%）符合RDD剂量定义（p<0.01）。肾功能受损（肌酐清除率<50 ml/min）患者的相应值分别为36%和42%。β-内酰胺类和大环内酯类药物存在较大的DDD差异（<50%的处方剂量符合DDD定义），而氨基糖苷类药物存在较大的RDD差异。与PDD相比，使用DDD作为医院抗生素使用量的衡量指标高估了抗生素使用量32%，而使用RDD则导致轻微低估（-9%）。
目前WHO/ATC定义的DDD用于衡量医院抗生素消耗量可能会大幅高估抗生素使用密度，而使用实践指南衍生的RDD可能会得出更有效的抗生素暴露估计值，这将有助于抗生素消耗的横断面和纵向分析。
