■最近,研究表明,使用霍乱疫苗可降低结直肠癌(CRC)患者的死亡风险.然而,关于旅行疫苗异源效应的证据有限。这项研究的目的是研究旅行疫苗对CRC患者的异源效应。
我们在2005年7月至2017年12月期间,对瑞典的一组CRC患者及其诊断后使用旅行药物的情况进行了回顾性数据库研究。我们从国家注册中心获得了CRC诊断数量的数据,死于CRC或其他原因,诊断时的年龄,以及诊断后使用旅行疫苗和疟疾预防。使用Cox回归模型通过诊断后旅行用药状态计算CRC相关死亡率和全因死亡率的发生率和发生率比率。
■确定了二百九十五名暴露于旅行疫苗和疟疾预防的患者和73,466名未暴露于旅行药物的患者。与未暴露患者相比,暴露患者的CRC相关死亡率降低,无论使用何种旅行药物。CRC相关死亡率和总死亡率的发生率比率相当。
■我们假设健康状况较好的患者可能比健康状况较差的患者更频繁地旅行。导致健康的用户偏见。结果同样表明,由于所有调查的旅行药物都发现了类似的降低死亡率的风险,降低治疗后使用任何研究的旅行药物的真正保护作用的生物学合理性。我们提倡使用多重阴性暴露对照,并在从旅行疫苗研究中得出结论时谨慎行事。
UNASSIGNED: Recently, cholera vaccine use was shown to be associated with a reduced risk of death in patients with colorectal cancer (CRC). However, evidence on heterologous effects of travel vaccines is limited. The aim of this study was to study heterologous effects of travel vaccines in patients with CRC.
UNASSIGNED: We performed a retrospective database study on a cohort of CRC patients in Sweden and their postdiagnostic use of travel medications between July 2005 and December 2017. We obtained data from national registries on number of CRC diagnosis, death from CRC or other causes, age at diagnosis, and postdiagnostic use of travel vaccines and malaria prophylaxis. The Cox regression model was used to calculate incidence rate and incidence rate ratios of CRC-related and all-cause mortality by postdiagnostic travel medication status.
UNASSIGNED: Two hundred ninety-five patients exposed to travel vaccines and malaria prophylaxis and 73,466 patients not exposed to travel medications were identified. CRC-related mortality was lowered in the exposed patients compared to the unexposed patients, irrespective of the travel medications used. The incidence rate ratios for CRC-related mortality and overall mortality were comparable.
UNASSIGNED: We postulated that patients in better health were likely to travel more frequently than patients with poor health, leading to a healthy user bias. The results suggested the same, as similar reduced mortality risks were found for all the investigated travel medications, lowering the biological plausibility of truly protective effect from post-therapeutic use of any of the travel medication studied. We advocate the use of multiple negative exposure controls and to exercise caution while drawing conclusions from travel vaccine research.