Julius Center for Health Sciences and Primary Care, University Medical Center (UMC) Utrecht, Utrecht University, Utrecht, The Netherlands.
Department of Internal Medicine, Division of Infectious Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.
Clin Infect Dis. 2023 Jul 5;77(1):9-15. doi: 10.1093/cid/ciad112.
Several studies have suggested that in patients with Staphylococcus aureus bacteremia (SAB) [18F] fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG-PET/CT) improves outcome. However, these studies often ignored possible immortal time bias.
Prospective multicenter cohort study in 2 university and 5 non-university hospitals, including all patients with SAB. [18F]FDG-PET/CT was performed on clinical indication as part of usual care. Primary outcome was 90-day all-cause mortality. Effect of [18F]FDG-PET/CT was modeled with a Cox proportional hazards model using [18F]FDG-PET/CT as a time-varying variable and corrected for confounders for mortality (age, Charlson score, positive follow-up cultures, septic shock, and endocarditis). Secondary outcome was 90-day infection-related mortality (assessed by adjudication committee) using the same analysis. In a subgroup-analysis, we determined the effect of [18F]FDG-PET/CT in patients with high risk of metastatic infection.
Of 476 patients, 178 (37%) underwent [18F]FDG-PET/CT. Day-90 all-cause mortality was 31% (147 patients), and infection-related mortality was 17% (83 patients). The confounder adjusted hazard ratio (aHR) for all-cause mortality was 0.50 (95% confidence interval [CI]: .34-.74) in patients that underwent [18F]FDG-PET/CT. Adjustment for immortal time bias changed the aHR to 1.00 (95% CI .68-1.48). Likewise, after correction for immortal time bias, [18F]FDG-PET/CT had no effect on infection-related mortality (cause specific aHR 1.30 [95% CI .77-2.21]), on all-cause mortality in patients with high-risk SAB (aHR 1.07 (95% CI .63-1.83) or on infection-related mortality in high-risk SAB (aHR for 1.24 [95% CI .67-2.28]).
After adjustment for immortal time bias [18F]FDG-PET/CT was not associated with day-90 all-cause or infection-related mortality in patients with SAB.
多项研究表明，18 氟脱氧葡萄糖正电子发射断层扫描/计算机断层扫描（18F-FDG-PET/CT）可改善金黄色葡萄球菌菌血症（SAB）患者的预后。然而，这些研究往往忽略了可能存在的不朽时间偏倚。
这是一项在 2 所大学医院和 5 所非大学医院进行的前瞻性多中心队列研究，纳入所有 SAB 患者。18F-FDG-PET/CT 是根据临床指征作为常规治疗的一部分进行的。主要结局为 90 天全因死亡率。采用 Cox 比例风险模型对 18F-FDG-PET/CT 的作用进行建模，将 18F-FDG-PET/CT 作为时变变量，并校正死亡率的混杂因素（年龄、Charlson 评分、阳性随访培养物、感染性休克和心内膜炎）。使用相同的分析方法，评估次要结局 90 天感染相关死亡率（由裁决委员会评估）。在亚组分析中，我们确定了 18F-FDG-PET/CT 在高转移性感染风险患者中的作用。
在 476 名患者中，有 178 名（37%）接受了 18F-FDG-PET/CT 检查。90 天全因死亡率为 31%（147 例），感染相关死亡率为 17%（83 例）。接受 18F-FDG-PET/CT 的患者全因死亡率的混杂因素校正危险比（aHR）为 0.50（95%可信区间 [CI]：0.34-0.74）。校正不朽时间偏倚后，aHR 变为 1.00（95%CI：0.68-1.48）。同样，校正不朽时间偏倚后，18F-FDG-PET/CT 对感染相关死亡率无影响（病因特异性 aHR 为 1.30[95%CI：0.77-2.21]），对高危 SAB 患者的全因死亡率也无影响（aHR 为 1.07[95%CI：0.63-1.83]），或对高危 SAB 患者的感染相关死亡率无影响（aHR 为 1.24[95%CI：0.67-2.28]）。
校正不朽时间偏倚后，18F-FDG-PET/CT 与 SAB 患者 90 天全因或感染相关死亡率无关。
