Department of Cardiology, Danderyd Hospital, Stockholm, Sweden.
Europace. 2011 May;13(5):626-33. doi: 10.1093/europace/eur001. Epub 2011 Feb 4.
Cardiovascular (CV)-related hospitalization has been used as a surrogate endpoint for mortality in recent treatment studies on atrial fibrillation (AF), but our understanding of the relationship between CV-related hospitalization and death is incomplete. We aimed to investigate whether CV-related hospitalization is an independent risk factor and suitable as a surrogate endpoint for death in clinical studies of patients with AF.
All 2912 patients with a diagnosis of AF in 2002 at one of Sweden's largest hospitals were studied for 6.5 years using information about medication from the local medical records. In a sub-study of the last 2.5 years of the study period, we used detailed information about medication from the new National Prescription Register. Information about diagnoses, hospitalizations, and deaths was obtained from national registries. Patients who were re-admitted to hospital with a CV diagnosis within the first 3 months had higher mortality than those who were not (15.6 vs. 9.3 deaths per 100 patient-years at risk, P < 0.0001). Those who spent >2% of their time-at-risk in hospital with a CV diagnosis had higher mortality than those who had spent less time in hospital (36.0 vs. 8.2 deaths per 100 patient years, P < 0.0001). After adjustment for co-factors, mortality was still higher for patients who had been re-hospitalized for CV disease within 3 months than for those who had not [hazard ratio (HR) = 1.36; 95% confidence interval (CI) = 1.18-1.57]. When analyses were performed on patients who had survived for 3 years since inclusion, and with the use of detailed information about the exposure to medication, the association between CV-related hospitalization and death was highly significant (HR 2.69, CI 1.96-3.68). These results were virtually unchanged after propensity score matching, which was done in order to adjust further for residual unidentified confounding.
CV-related hospitalization is a marker for patients who are at increased risk of death, and may be used as a valid surrogate endpoint in studies of AF.
心血管（CV）相关住院治疗已被用作近期房颤（AF）治疗研究中死亡率的替代终点，但我们对 CV 相关住院治疗与死亡之间的关系了解尚不完整。本研究旨在探讨 CV 相关住院治疗是否为 AF 患者临床研究中的独立危险因素和合适的死亡替代终点。
在瑞典最大的一家医院 2002 年确诊的 2912 例 AF 患者中，通过当地病历中的药物信息对所有患者进行了为期 6.5 年的研究。在研究期间的最后 2.5 年的子研究中，我们使用了新的国家处方登记处中有关药物的详细信息。通过国家登记处获得了诊断、住院和死亡信息。在首次 3 个月内因 CV 诊断再次住院的患者死亡率高于未住院的患者（每 100 例风险患者死亡 15.6 例与 9.3 例，P<0.0001）。在 CV 诊断住院治疗期间，有>2%的时间处于风险状态的患者死亡率高于住院时间较短的患者（每 100 例风险患者死亡 36.0 例与 8.2 例，P<0.0001）。在校正协变量后，3 个月内因 CV 疾病再次住院的患者死亡率仍高于未住院的患者[风险比（HR）=1.36；95%置信区间（CI）=1.18-1.57]。当对纳入后存活 3 年的患者进行分析，并使用有关药物暴露的详细信息时，CV 相关住院治疗与死亡之间的关联具有高度显著性（HR 2.69，CI 1.96-3.68）。在进一步校正潜在未识别的混杂因素后进行倾向评分匹配，结果几乎不变。
CV 相关住院治疗是患者死亡风险增加的标志物，可作为 AF 研究中的有效替代终点。
