Davila Jesse A, Johnson C Daniel, Behrenbeck Thomas R, Hoskin Tanya L, Harmsen William S
Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA.
Radiology. 2006 Jul;240(1):110-5. doi: 10.1148/radiol.2401050948.
To retrospectively determine whether calcium scores of the abdominal aorta obtained during computed tomographic (CT) colonography relate to Framingham risk factors and clinical cardiac events.
The institutional review board approved the current HIPAA-compliant retrospective study and waived informed consent. Between 1995 and 1998, 480 patients underwent CT colonography; 467 patients were available for assessment. Calcium scores with a threshold attenuation value of 130 HU or greater were recorded for abdominal aorta (suprarenal, infrarenal, and aortic bifurcation regions and total). Patient histories were abstracted for established cardiac risk factors and subsequent cardiac events. Associations between calcium measurements and binary risk factors were assessed with Wilcoxon rank sum test; those with continuous risk factors, with Spearman rank correlation coefficient; and those with combined end points, with Cox proportional hazards model.
Follow-up data were available for 467 patients with median age of 65 years (range, 34-83 years); 59% (275 of 467) were men. Nine patients had cardiac events subsequent to CT colonography. Results of proportional hazards regression analysis revealed a significant association between myocardial infarction or cardiac event-related death and calcium scores of the aortic bifurcation that exceeded 895, the value for the 75th percentile for this calcium variable (P < .01). Associations with established cardiac risk factors for all four calcium scores were significant (P < .05). Spearman rank correlation coefficients for associations between total calcium score and patient characteristics of age, number of pack-years of smoking, and systolic blood pressure were 0.51, 0.43, and 0.29, respectively (P < .001 for all).
Aortic calcification scores at CT colonography are significantly associated with established cardiac risk factors and cardiac-related events. This screening information can be obtained without additional scanning or risk to the patient.
回顾性确定在计算机断层扫描（CT）结肠成像期间获得的腹主动脉钙化评分是否与弗明汉姆风险因素及临床心脏事件相关。
机构审查委员会批准了这项符合当前健康保险流通与责任法案（HIPAA）的回顾性研究，并豁免了知情同意。1995年至1998年间，480例患者接受了CT结肠成像检查；467例患者可供评估。记录腹主动脉（肾上腺上方、肾下及主动脉分叉区域和总体）的钙化评分，阈值衰减值为130 HU或更高。提取患者既往史中的既定心脏风险因素及随后的心脏事件。用Wilcoxon秩和检验评估钙化测量值与二元风险因素之间的关联；与连续风险因素的关联用Spearman秩相关系数评估；与合并终点的关联用Cox比例风险模型评估。
467例患者有随访数据，中位年龄65岁（范围34 - 83岁）；59%（467例中的275例）为男性。9例患者在CT结肠成像后发生心脏事件。比例风险回归分析结果显示，心肌梗死或心脏事件相关死亡与主动脉分叉处钙化评分超过895（该钙化变量第75百分位数的值）之间存在显著关联（P < 0.01）。所有四个钙化评分与既定心脏风险因素的关联均显著（P < 0.05）。总钙化评分与年龄、吸烟包年数及收缩压等患者特征之间的Spearman秩相关系数分别为0.51、0.43和0.29（均P < 0.001）。
CT结肠成像时的主动脉钙化评分与既定心脏风险因素及心脏相关事件显著相关。无需对患者进行额外扫描或使其承担风险即可获得此筛查信息。
