Habermann Theresa, Wafula Solomon T, May Jürgen, Lorenz Eva, Puradiredja Dewi Ismajani
Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
Department of Disease Control and Environmental Health, School of Public Health, Makerere University, Kampala, Uganda.
Malar J. 2024 Dec 13;23(1):370. doi: 10.1186/s12936-024-05204-6.
Children under five continue to bear a disproportionate burden of malaria morbidity and mortality in endemic countries. While the link between socioeconomic position (SEP) and malaria is well established, the causal pathways remain poorly understood, hindering the design and implementation of more targeted structural interventions. This study examines the association between SEP and malaria among children in Ghana and explores the potential mediating role of behavioural and socio-structural factors.
Data from the Ghana Demographic and Health Survey (DHS) 2022 were analysed. As part of the survey, children were tested for malaria using a rapid diagnostic test (RDT), and SEP was measured using a household asset-based wealth index. Mediation analysis (MA) using a regression-based approach was performed to assess mediated effects between SEP and malaria in children under five in Ghana through housing quality, educational attainment (EA), long-lasting insecticidal net (LLIN) use, indoor residual spraying (IRS), and healthcare-seeking behaviour (HSB). Reported are the total natural indirect effects (TNIEs) and the proportion mediated (PM).
Of the 3,884 children included in the survey, 19.4% (757) had malaria. Belonging to a household with high SEP was associated with a 43% lower risk of malaria (Prevalence Ratio, PR = 0.57; 95% Confidence Interval, CI 0.46-0.71). Regarding indirect (mediated) effects, maternal EA of secondary school or higher (OR = 0.68; 95% CI 0.60-0.77; PM = 17.5%), improved housing (OR = 0.80; 95% CI 0.68-0.91, PM = 9.2%), LLIN use (OR = 0.95; 95% CI 0.90-0.99, PM = 2.1%) partially mediated the association between SEP and malaria. The combined effect of all three mediators was higher than those in a single mediator or two sequential mediators (with EA as the initial mediator) (OR = 0.58; 95% CI 0.51-0.68, PM = 25.7%). No evidence of mediation was observed for HSB and IRS.
We found evidence of mediation by EA, housing, LLIN use and IRS, suggesting that current biomedical and behavioural malaria control efforts could be complemented with structural interventions, such as improved housing and education. Future studies that test the effect of different or joint effects of multiple mediators based on prospective designs are recommended to strengthen the evidence.
在疟疾流行国家,五岁以下儿童仍然承受着不成比例的疟疾发病和死亡负担。虽然社会经济地位(SEP)与疟疾之间的联系已得到充分证实,但其因果途径仍知之甚少,这阻碍了更具针对性的结构性干预措施的设计和实施。本研究调查了加纳儿童SEP与疟疾之间的关联,并探讨了行为和社会结构因素的潜在中介作用。
对2022年加纳人口与健康调查(DHS)的数据进行了分析。作为调查的一部分,使用快速诊断测试(RDT)对儿童进行疟疾检测,并使用基于家庭资产的财富指数来衡量SEP。采用基于回归的方法进行中介分析(MA),以评估通过住房质量、教育程度(EA)、长效驱虫蚊帐(LLIN)的使用、室内残留喷洒(IRS)和就医行为(HSB)在加纳五岁以下儿童中SEP与疟疾之间的中介效应。报告了总自然间接效应(TNIEs)和中介比例(PM)。
在调查纳入的3884名儿童中,19.4%(757名)患有疟疾。属于高SEP家庭的儿童患疟疾的风险降低43%(患病率比,PR = 0.57;95%置信区间,CI 0.46 - 0.71)。关于间接(中介)效应,母亲中学及以上教育程度(OR = 0.68;95% CI 0.60 - 0.77;PM = 17.5%)、住房改善(OR = 0.80;95% CI 0.68 - 0.91,PM = 9.2%)、LLIN使用(OR = 0.95;95% CI 0.90 - 0.99,PM = 2.1%)部分中介了SEP与疟疾之间的关联。所有三种中介因素的综合效应高于单一中介因素或两个连续中介因素(以EA作为初始中介因素)的效应(OR = 0.58;95% CI 0.51 - 0.68,PM = 25.7%)。未观察到HSB和IRS的中介证据。
我们发现了EA、住房、LLIN使用和IRS中介作用的证据,这表明当前的生物医学和行为疟疾控制措施可以辅以结构性干预措施,如改善住房和教育。建议未来基于前瞻性设计测试不同或多种中介因素联合效应的研究,以加强证据。