Brown Laura J, Sear Rebecca
Department of Population Health, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
Evol Med Public Health. 2017 Aug 21;2017(1):120-135. doi: 10.1093/emph/eox011. eCollection 2017.
Breastfeeding is an important form of parental investment with clear health benefits. Despite this, rates remain low in the UK; understanding variation can therefore help improve interventions. Life history theory suggests that environmental quality may pattern maternal investment, including breastfeeding. We analyse a nationally representative dataset to test two predictions: (i) higher local environmental quality predicts higher likelihood of breastfeeding initiation and longer duration; (ii) higher socioeconomic status (SES) provides a buffer against the adverse influences of low local environmental quality. We ran factor analysis on a wide range of local-level environmental variables. Two summary measures of local environmental quality were generated by this analysis-one 'objective' (based on an independent assessor's neighbourhood scores) and one 'subjective' (based on respondent's scores). We used mixed-effects regression techniques to test our hypotheses. Higher objective, but not subjective, local environmental quality predicts higher likelihood of starting and maintaining breastfeeding over and above individual SES and area-level measures of environmental quality. Higher individual SES is protective, with women from high-income households having relatively high breastfeeding initiation rates and those with high status jobs being more likely to maintain breastfeeding, even in poor environmental conditions. Environmental quality is often vaguely measured; here we present a thorough investigation of environmental quality at the local level, controlling for individual- and area-level measures. Our findings support a shift in focus away from individual factors and towards altering the landscape of women's decision making contexts when considering behaviours relevant to public health.
母乳喂养是一种重要的亲代投资形式，具有明显的健康益处。尽管如此，英国的母乳喂养率仍然很低；因此，了解其中的差异有助于改进相关干预措施。生命史理论表明，环境质量可能会影响母亲的投资行为，包括母乳喂养。我们分析了一个具有全国代表性的数据集，以检验两个预测：（i）当地环境质量越高，母乳喂养开始的可能性越高，持续时间越长；（ii）较高的社会经济地位（SES）可以缓冲当地低环境质量的不利影响。我们对一系列当地层面的环境变量进行了因子分析。通过该分析生成了两个当地环境质量的综合指标——一个是“客观的”（基于独立评估者对社区的评分），另一个是“主观的”（基于受访者的评分）。我们使用混合效应回归技术来检验我们的假设。较高的客观而非主观的当地环境质量预测了在个体SES和地区层面环境质量指标之外开始和维持母乳喂养的更高可能性。较高的个体SES具有保护作用，来自高收入家庭的女性母乳喂养开始率相对较高，从事高地位工作的女性即使在恶劣的环境条件下也更有可能维持母乳喂养。环境质量的衡量往往比较模糊；在这里，我们对当地层面的环境质量进行了全面调查，同时控制了个体和地区层面的指标。我们的研究结果支持了一种重点转移，即从关注个体因素转向在考虑与公共卫生相关的行为时改变女性决策环境的格局。
