Centre for Research on Pandemics & Society, Oslo Metropolitan University, Oslo, Norway.
Work Research Institute, Oslo Metropolitan University, Oslo, Norway.
PLoS One. 2021 Sep 7;16(9):e0244346. doi: 10.1371/journal.pone.0244346. eCollection 2021.
The objective of this study is to document whether and to what extent there is an association between socioeconomic status (SES) and disease outcomes in the last five influenza pandemics.
METHODS/PRINCIPLE FINDINGS: The review included studies published in English, Danish, Norwegian and Swedish. Records were identified through systematic literature searches in six databases. We summarized results narratively and through meta-analytic strategies. Only studies for the 1918 and 2009 pandemics were identified. Of 14 studies on the 2009 pandemic including data on both medical and social risk factors, after controlling for medical risk factors 8 demonstrated independent impact of SES. In the random effect analysis of 46 estimates from 35 studies we found a pooled mean odds ratio of 1.4 (95% CI: 1.2-1.7, p < 0.001), comparing the lowest to the highest SES, but with substantial effect heterogeneity across studies,-reflecting differences in outcome measures and definitions of case and control samples. Analyses by pandemic period (1918 or 2009) and by level of SES measure (individual or ecological) indicated no differences along these dimensions. Studies using healthy controls tended to document that low SES was associated with worse influenza outcome, and studies using infected controls find low SES associated with more severe outcomes. A few studies compared severe outcomes (ICU or death) to hospital admissions but these did not find significant SES associations in any direction. Studies with more unusual comparisons (e.g., pandemic vs seasonal influenza, seasonal influenza vs other patient groups) reported no or negative non-significant associations.
CONCLUSIONS/SIGNIFICANCE: We found that SES was significantly associated with pandemic influenza outcomes with people of lower SES having the highest disease burden in both 1918 and 2009. To prepare for future pandemics, we must consider social vulnerability. The protocol for this study has been registered in PROSPERO (ref. no 87922) and has been published Mamelund et al. (2019).
本研究旨在记录在过去五次流感大流行中，社会经济地位（SES）与疾病结局之间是否存在关联，以及关联程度如何。
方法/主要发现：综述纳入了发表于英文、丹麦文、挪威文和瑞典文的研究。通过在六个数据库中进行系统文献检索来确定记录。我们通过叙述性和荟萃分析策略总结结果。仅确定了针对 1918 年和 2009 年大流行的研究。在纳入了医疗和社会风险因素数据的 2009 年大流行的 14 项研究中，在控制了医疗风险因素后，有 8 项研究显示 SES 具有独立影响。在对来自 35 项研究的 46 个估计值进行的随机效应分析中，我们发现最低 SES 与最高 SES 相比，优势比的合并平均值为 1.4（95%CI：1.2-1.7，p<0.001），但研究之间存在显著的效应异质性，这反映了结局测量和病例与对照样本的定义存在差异。按大流行时期（1918 年或 2009 年）和 SES 测量水平（个体或生态）进行的分析并未显示出这些维度的差异。使用健康对照的研究倾向于证明低 SES 与流感结局较差相关，而使用感染对照的研究则发现低 SES 与更严重的结局相关。少数研究比较了严重结局（ICU 或死亡）与住院治疗，但在任何方向上都没有发现 SES 存在显著关联。使用更不寻常的比较（例如，大流行流感与季节性流感、季节性流感与其他患者群体）的研究报告称没有或没有发现非显著负相关。
结论/意义：我们发现 SES 与大流行流感结局显著相关，在 1918 年和 2009 年，SES 较低的人群疾病负担最高。为了为未来的大流行做准备，我们必须考虑社会脆弱性。本研究的方案已在 PROSPERO（注册号 87922）中注册，并由 Mamelund 等人发表。
