Tang Jun, Wan Jim Y, Bailey James E
Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, Tenn, USA.
Stroke. 2008 Jul;39(7):1938-44. doi: 10.1161/STROKEAHA.107.504688. Epub 2008 Apr 24.
The Charlson and Elixhauser comorbidities are widely used to control for differences in comorbidity in epidemiological studies but have not been validated for outpatient studies of hypertension. This study sought that validation using death and stroke outcomes.
Using Cox models in a retrospective cohort study of 49,479 hypertensive patients, Modified Charlson Index was compared with 6 alternative approaches to assessing comorbidity: individual Charlson comorbidities, Elixhauser comorbidities, prior major cardiovascular disease event, traditional risk factors for cerebrovascular accident, healthcare utilization, and antihypertensive medication utilization. Comorbidity measures were calculated at baseline and for a period before occurrence of the study outcome of interest or study conclusion.
The Charlson comorbidities had the smallest Akaike information criterion value for both the stroke and death outcomes when baseline data were used. The Elixhauser comorbidities had the smallest Akaike information criterion value for both the stroke and death outcomes when follow-up data were used. Modified Charlson Index also predicted stroke and death, but alternative models were more robust.
This study indicates that both the Charlson and Elixhauser comorbidities are valid prediction tools that could enable clinicians and health systems to better assess risk for stroke and death in patients with hypertension. However, the Charlson comorbidities perform better when comorbidities are assessed using baseline data, whereas the Elixhauser comorbidities perform better for short follow-up periods when comorbidities are assessed proximal to events of interest.
查尔森合并症指数和埃利克斯豪泽合并症指数在流行病学研究中被广泛用于控制合并症差异，但尚未在高血压门诊研究中得到验证。本研究旨在通过死亡和卒中结局来进行验证。
在一项对49479例高血压患者的回顾性队列研究中，使用Cox模型，将改良查尔森指数与6种评估合并症的替代方法进行比较：个体查尔森合并症、埃利克斯豪泽合并症、既往重大心血管疾病事件、脑血管意外的传统危险因素、医疗服务利用情况以及抗高血压药物使用情况。在基线时以及在感兴趣的研究结局或研究结论出现之前的一段时间内计算合并症指标。
使用基线数据时，查尔森合并症在卒中和死亡结局方面的赤池信息准则值最小。使用随访数据时，埃利克斯豪泽合并症在卒中和死亡结局方面的赤池信息准则值最小。改良查尔森指数也能预测卒中和死亡，但替代模型更稳健。
本研究表明，查尔森合并症指数和埃利克斯豪泽合并症指数都是有效的预测工具，可使临床医生和卫生系统更好地评估高血压患者的卒中和死亡风险。然而，使用基线数据评估合并症时，查尔森合并症指数表现更好；而在短随访期内，在接近感兴趣事件时评估合并症，埃利克斯豪泽合并症指数表现更好。
