Merlo J, Ostergren P O, Broms K, Bjorck-Linné A, Liedholm H
Department of Community Medicine, Malmö University Hospital, Lund University, Malmö, Sweden.
J Epidemiol Community Health. 2001 May;55(5):323-9. doi: 10.1136/jech.55.5.323.
Although national variation in short-term prognosis (that is, 30 day mortality) after a patient's first hospitalisation for heart failure may depend on individual differences between patients, dissimilarities in hospital practices may also influence prognosis. This study, therefore, sought to disentangle patient determinants from institutional factors that might explain such variation.
A multilevel logistic regression modelling was performed with patients (1st level) nested in hospitals (2nd level). Institutional effects (that is, 2nd level variance and intra-hospital correlation) were calculated unadjusted and adjusted for specific patient (that is, age and previous diseases) and institutional (that is, size of hospital) characteristics. Patients were followed up until death or 30 days from hospital admission.
Hospitals in Sweden.
The study identified all the 20420 men and 17923 women (ages 65 to 85) admitted to the 90 acute care hospitals in Sweden during the period 1992-1995 for their first hospitalisation attributable to heart failure.
Patient age and previous diseases (particularly senile dementia) were major determinants of impaired prognosis. Institutional factors explained only 1.6% and 2.3% of the total variation in 30 day mortality in men and women, respectively. These modest institutional effects remained after adjusting for patient age and previous diseases, but were in part explained by hospital size.
National variation in short-term prognosis after an initial hospitalisation for heart failure was mainly explained by differences between patients, with hospital factors playing a minor part. Of the latter, hospital size seemed to emerge as one determinant (that is, the greater the number of patients, the better the individual prognosis).
虽然患者首次因心力衰竭住院后的短期预后（即30天死亡率）存在国家间差异可能取决于患者个体差异，但医院诊疗行为的不同也可能影响预后。因此，本研究旨在区分可能解释这种差异的患者决定因素和机构因素。
采用多级逻辑回归模型，患者（第一级）嵌套于医院（第二级）。计算未调整的机构效应（即第二级方差和医院内相关性），并针对特定患者（即年龄和既往疾病）和机构（即医院规模）特征进行调整。对患者进行随访直至死亡或入院后30天。
瑞典的医院。
该研究纳入了1992年至1995年期间因首次心力衰竭住院而入住瑞典90家急性护理医院的所有20420名男性和17923名女性（年龄65至85岁）。
患者年龄和既往疾病（尤其是老年痴呆症）是预后受损的主要决定因素。机构因素分别仅解释了男性和女性30天死亡率总变异的1.6%和2.3%。在调整患者年龄和既往疾病后，这些适度的机构效应仍然存在，但部分可由医院规模解释。
首次因心力衰竭住院后的短期预后存在国家间差异，主要由患者个体差异解释，医院因素起次要作用。在后者中，医院规模似乎是一个决定因素（即患者数量越多，个体预后越好）。
