Widga A C, Lewis N M
Department of Nutritional Science and Dietetics, University of Nebraska, Lincoln 68583-0806, USA.
J Am Diet Assoc. 1999 Sep;99(9):1058-62; quiz 1063-4, 1175. doi: 10.1016/S0002-8223(99)00251-5.
The purpose of this project was to develop a detailed, in-home, prenatal nutrition intervention protocol for low-income women and to assess the effectiveness of the intervention in improving their dietary intake. A secondary objective was to identify predictors of infant birth weight.
A defined protocol was developed and nutritionists followed it to conduct in-home nutrition sessions that included nutrition assessment, education, counseling, and goal setting for low-income women during their pregnancies. A pre/post design was used to assess the effects of the nutrition program on dietary intake. A control group was used in evaluating the effect of the nutrition intervention on birth weight.
SUBJECTS/SETTING: Forty low-income pregnant women selected randomly by the county health department nursing staff completed the nutrition intervention. Twenty-six women were also selected to serve as a control group.
For women in the intervention group, in-home visits were conducted weekly for 4 weeks, followed by 2 monthly visits. The purpose of the in-home visits was to use the defined protocol, which included monitoring weight gain and providing individualized dietary intake assessment and nutrition education and counseling.
The primary outcome measures were change in dietary intake from preintervention to postintervention, mothers' weight at time of delivery, and infant birth weight.
Paired t tests were used to compare the women's mean daily energy and nutrient intakes before and after the nutrition intervention. Correlation analysis identified relationships between infant birth weight and independent variables, and multiple stepwise regression analysis was used to identify variables that contributed to the variation in infant birth weight. Mean birth weight was compared in the intervention and control groups by means of a t test. A chi 2 test was used for categoric variables.
Comparison of dietary intakes before and after the intervention revealed significant increases in total energy (2,269 to 2,431 kcal, P < .05), folate (345 to 412 micrograms, P < .01), vitamin B-6 (2.1 to 2.5 mg, P < .01), iron (17.5 to 21.2 mg, P < .01), zinc (13.6 to 14.7 mg, P < .01), and calcium (1,175 mg to 1,299 mg, P < .01) and significant (P < .01) increases in daily servings from the vegetable group (1.5 +/- 1.0 to 2.2 +/- 1.1 serving per day) and breads/grains groups (3.4 +/- 1.4 to 4.1 +/- 1.5 servings per day). There was no significant difference in mean birth weight between the intervention and control groups. Sixty-five percent of the variation in infant birth weight was accounted for by mother's weight at time of delivery, pre-pregnancy body mass index, number of visits by the nutritionist, and change in energy intake from preintervention to postintervention.
This defined, in-home, prenatal nutrition intervention protocol can be used by providers of prenatal nutrition services to document outcomes of prenatal nutrition care in high-risk women. Use of a defined protocol will facilitate collection of meaningful outcomes data by service providers.
本项目旨在为低收入女性制定一份详细的居家产前营养干预方案,并评估该干预措施在改善她们饮食摄入方面的效果。次要目标是确定婴儿出生体重的预测因素。
制定了明确的方案,营养师按照该方案为低收入孕妇进行居家营养指导,包括营养评估、教育、咨询以及孕期目标设定。采用前后对照设计评估营养项目对饮食摄入的影响。设立对照组以评估营养干预对出生体重的影响。
研究对象/地点:由县卫生部门护理人员随机挑选的40名低收入孕妇完成了营养干预。另外挑选了26名女性作为对照组。
干预组女性每周进行1次为期4周的家访,之后每月家访2次。家访目的是按照既定方案进行,包括监测体重增加情况,并提供个性化饮食摄入评估以及营养教育与咨询。
主要观察指标为干预前后饮食摄入的变化、分娩时母亲的体重以及婴儿出生体重。
采用配对t检验比较营养干预前后女性的平均每日能量和营养素摄入量。相关分析确定婴儿出生体重与自变量之间的关系,多元逐步回归分析用于确定影响婴儿出生体重变化的变量。通过t检验比较干预组和对照组的平均出生体重。分类变量采用卡方检验。
干预前后饮食摄入量比较显示,总能量(从2269千卡增至2431千卡,P<.05)、叶酸(从345微克增至412微克,P<.01)、维生素B-6(从2.1毫克增至2.5毫克,P<.01)、铁(从17.5毫克增至21.2毫克,P<.01)、锌(从13.6毫克增至14.7毫克,P<.01)和钙(从1175毫克增至1299毫克,P<.01)均显著增加,蔬菜组(从每天1.5±1.0份增至2.2±1.1份)和面包/谷物组(从每天3.4±1.4份增至4.1±1.5份)的每日摄入量也显著增加(P<.01)。干预组和对照组的平均出生体重无显著差异。婴儿出生体重65%的变化可由分娩时母亲的体重、孕前体重指数、营养师家访次数以及干预前后能量摄入的变化来解释。
这份明确的居家产前营养干预方案可供产前营养服务提供者用于记录高危女性产前营养护理的结果。使用既定方案将便于服务提供者收集有意义的结果数据。