Classen D C, Pestotnik S L, Evans R S, Lloyd J F, Burke J P
Department of Clinical Epidemiology, LDS Hospital, Salt Lake City, UT 84143, USA.
JAMA. 1997;277(4):301-6.
To determine the excess length of stay, extra costs, and mortality attributable to adverse drug events (ADEs) in hospitalized patients.
Matched case-control study.
The LDS Hospital, a tertiary care health care institution.
All patients admitted to LDS Hospital from January 1, 1990, to December 31, 1993, were eligible. Cases were defined as patients with ADEs that occurred during hospitalization; controls were selected according to matching variables in a stepwise fashion.
Controls were matched to cases on primary discharge diagnosis related group (DRG), age, sex, acuity, and year of admission; varying numbers of controls were matched to each case. Matching was successful for 71% of the cases, leading to 1580 cases and 20,197 controls.
Crude and attributable mortality, crude and attributable length of stay, and cost of hospitalization.
ADEs complicated 2.43 per 100 admissions to the LDS Hospital during the study period. The crude mortality rates for the cases and matched controls were 3.5% and 1.05%, respectively (P<.001). The mean length of hospital stay significantly differed between the cases and matched controls (7.69 vs 4.46 days; P<.001) as did the mean cost of hospitalization ($10,010 vs $5355; P<.001). The extra length of hospital stay attributable to an ADE was 1.74 days (P<.001). The excess cost of hospitalization attributable to an ADE was $2013 (P<.001). A linear regression analysis for length of stay and cost controlling for all matching variables revealed that the occurrence of an ADE was associated with increased length of stay of 1.91 days and an increased cost of $2262 (P<.001). In a similar logistic regression analysis for mortality, the increased risk of death among patients experiencing an ADE was 1.88 (95% confidence interval, 1.54-2.22; P<.001).
The attributable lengths of stay and costs of hospitalization for ADEs are substantial. An ADE is associated with a significantly prolonged length of stay, increased economic burden, and an almost 2-fold increased risk of death.
确定住院患者因药物不良事件（ADEs）导致的住院时间延长、额外费用及死亡率。
配对病例对照研究。
LDS医院，一家三级医疗保健机构。
1990年1月1日至1993年12月31日期间入住LDS医院的所有患者均符合条件。病例定义为住院期间发生ADEs的患者；对照根据匹配变量逐步选择。
对照在主要出院诊断相关组（DRG）、年龄、性别、病情严重程度及入院年份方面与病例进行匹配；每个病例匹配不同数量的对照。71%的病例匹配成功，共1580例病例和20197例对照。
粗死亡率和归因死亡率、粗住院时间和归因住院时间以及住院费用。
在研究期间，LDS医院每100例入院患者中有2.43例发生ADEs并发症。病例组和匹配对照组的粗死亡率分别为3.5%和1.05%（P<0.001）。病例组和匹配对照组的平均住院时间（7.69天对4.46天；P<0.001）及平均住院费用（10010美元对5355美元；P<0.001）均有显著差异。因ADEs导致的额外住院时间为1.74天（P<0.001）。因ADEs导致的额外住院费用为2013美元（P<0.001）。对住院时间和费用进行线性回归分析并控制所有匹配变量后发现，ADEs的发生与住院时间延长1.91天及费用增加2262美元相关（P<0.001）。在类似的死亡率逻辑回归分析中，发生ADEs的患者死亡风险增加1.88倍（95%置信区间，1.54 - 2.22；P<0.001）。
ADEs导致的归因住院时间和住院费用相当可观。ADEs与住院时间显著延长、经济负担增加以及死亡风险几乎增加两倍相关。
