Genser Bernd, Strina Agostino, dos Santos Lenaldo A, Teles Carlos A, Prado Matildes S, Cairncross Sandy, Barreto Mauricio L
Instituto de Saúde Coletiva, Federal University of Bahia, Salvador, Brazil.
Int J Epidemiol. 2008 Aug;37(4):831-40. doi: 10.1093/ije/dyn101.
Poor socioeconomic status (SES) increases diarrhoea risk, mostly mediated by lack of sanitation, poor infrastructure and living conditions. The effectiveness of a city-wide sanitation intervention on diarrhoea in a large urban centre in Northeast Brazil has recently been demonstrated. This article aims to explore how this intervention altered the magnitude of relative and attributable risks of diarrhoea determinants and the pathways by which those factors affect diarrhoea risk.
We investigated determinants of prevalence of diarrhoea in two cohort studies conducted before and after the intervention. Each study enrolled pre-school children followed up for 8 months. For both cohorts, we calculated relative, attributable and mediated risks of diarrhoea determinants by a hierarchical effect decomposition strategy.
The intervention reduced diarrhoea and also changed attributable and relative risks of diarrhoea determinants by altering the pathways of mediation. Before the intervention SES was a major distal diarrhoea determinant (attributable risk: 24%) with 90% of risk mediated by other factors, mostly by lack of sanitation and poor infrastructure (53%). After the intervention, only 13% of risk was attributed to SES, with only 42% mediated by other factors (18% by lack of sanitation and poor infrastructure).
The intervention reduced diarrhoea risk by reducing direct exposure to unfavourable sanitation conditions. At the same time it altered the effect and mediation pathways of most distal diarrhoea determinants, especially SES. This finding corroborates the importance of public sanitation measures in reducing the impact of poverty on diarrhoea. It also underlines the value of studying the impact of public health interventions to improve our understanding of health determinants.
社会经济地位低下会增加腹泻风险，这主要是由卫生设施缺乏、基础设施差和生活条件恶劣所致。最近已证明在巴西东北部一个大型城市中心开展的全市范围的卫生干预措施对腹泻具有有效性。本文旨在探讨这一干预措施如何改变腹泻决定因素的相对风险和归因风险的大小，以及这些因素影响腹泻风险的途径。
我们在干预前后进行的两项队列研究中调查了腹泻患病率的决定因素。每项研究均纳入了随访8个月的学龄前儿童。对于这两个队列，我们通过分层效应分解策略计算了腹泻决定因素的相对风险、归因风险和中介风险。
该干预措施降低了腹泻发生率，还通过改变中介途径改变了腹泻决定因素的归因风险和相对风险。在干预之前，社会经济地位是腹泻的一个主要远端决定因素（归因风险：24%），90%的风险由其他因素介导，主要是卫生设施缺乏和基础设施差（53%）。干预后，只有13%的风险归因于社会经济地位，只有42%由其他因素介导（18%由卫生设施缺乏和基础设施差介导）。
该干预措施通过减少直接暴露于不利的卫生条件而降低了腹泻风险。同时，它改变了大多数远端腹泻决定因素的效应和中介途径，尤其是社会经济地位。这一发现证实了公共卫生措施在减少贫困对腹泻影响方面的重要性。它还强调了研究公共卫生干预措施影响以增进我们对健康决定因素理解的价值。
