The folate status of reproductive-aged women in a randomised trial of a folate-fortified oral contraceptive: dietary and blood assessments

[Factors associated with inadequate folic acid supplementation for the prevention of neural tube defects in eight Parisian maternity units]

OBJECTIVES

Despite the guidelines in effect, too few women in France receive folic acid supplementation. The principal objective of this study was to identify the factors associated with the inadequacy of this supplementation in the periconceptional period. The secondary objective was to assess women's knowledge about the prevention of neural tube defects (NTDs).

METHODS

This study included 400 women and took place in 8 Parisian maternity. Folic acid supplementation was inadequate when started after the beginning of the pregnancy.

RESULTS

Among the women questioned, 68% had inadequate folic acid supplementation. They were significantly younger (ORa= 1,8; 95% IC [1,1-2,8]), didn't had health insurance (ORa=3,9; 95% IC [1,5-10,1]), had not studied after high school (ORa=2,9; 95% IC [1,2-6,9]) and had regular gynecological care less often than the women with adequate supplementation (ORa=3,0; 95% IC [1,6-5,6]). More than half (55.5%) had insufficient knowledge of the benefits of folic acid; the factors related to this lack of knowledge were the absence of regular gynecological care and of health insurance.

CONCLUSION

Individual factors associated with a lack of supplementation have been identified. These results provide health professionals and supervisors with useful information for developing strategies adapted to certain subgroups of women for better prevention of AFTN in these populations.

Evidence of Drug-Nutrient Interactions with Chronic Use of Commonly Prescribed Medications: An Update

The long-term use of prescription and over-the-counter drugs can induce subclinical and clinically relevant micronutrient deficiencies, which may develop gradually over months or even years. Given the large number of medications currently available, the number of research studies examining potential drug-nutrient interactions is quite limited. A comprehensive, updated review of the potential drug-nutrient interactions with chronic use of the most often prescribed medications for commonly diagnosed conditions among the general U.S. adult population is presented. For the majority of the interactions described in this paper, more high-quality intervention trials are needed to better understand their clinical importance and potential consequences. A number of these studies have identified potential risk factors that may make certain populations more susceptible, but guidelines on how to best manage and/or prevent drug-induced nutrient inadequacies are lacking. Although widespread supplementation is not currently recommended, it is important to ensure at-risk patients reach their recommended intakes for vitamins and minerals. In conjunction with an overall healthy diet, appropriate dietary supplementation may be a practical and efficacious way to maintain or improve micronutrient status in patients at risk of deficiencies, such as those taking medications known to compromise nutritional status. The summary evidence presented in this review will help inform future research efforts and, ultimately, guide recommendations for patient care.

The Effectiveness of Folate-Fortified Oral Contraceptives in Maintaining Optimal Folate Levels to Protect Against Neural Tube Defects: A Systematic Review

OBJECTIVE

To conduct a systematic review evaluating the effectiveness of a folate-fortified oral contraceptive preparation in increasing blood folate concentrations to levels providing optimal protection against neural tube defects (> 906 nmol/L).

METHODS

We searched Medline, EMBASE, Web of Science, and the Cochrane Library for human studies published from inception to June 2013 that evaluated oral contraceptive use and folate status. Case-control studies, cohort studies, and clinical trials were included. Efficacy and bioequivalence data were evaluated from included studies.

RESULTS

Overall, efficacy and bioequivalence data for the folate-fortified oral contraceptive show that it is at least as effective as folic acid alone in raising blood folate concentrations, and that the concomitant administration of folate with the oral contraceptive component does not affect its absorption or kinetics.

CONCLUSION

A folate-fortified oral contraceptive preparation provides an option for women to maintain blood folate levels, especially those who may be planning a family after the cessation of oral contraceptive therapy.

Association Between Use of Oral Contraceptives and Folate Status: A Systematic Review and Meta-Analysis

OBJECTIVE

To conduct a systematic review and meta-analysis of the effect of oral contraceptive use on plasma and red blood cell (RBC) folate concentrations.

METHODS

We searched Medline, EMBASE, Web of Science, and the Cochrane library for human studies published from inception to June 2013 evaluating oral contraceptive use and folate status. Case-control studies, cohort studies, and clinical trials were included. A random-effects model of outcomes was used for the meta-analysis.

RESULTS

A total of 2831 women in 17 studies were included in the analysis. In those whose plasma folate concentrations were available, there was a significant folate-lowering effect of oral contraceptives observed (mean reduction 1.27 µg/L; 95% CI 1.85 to 0.69, P < 0.001). Similarly, after analyzing data from 1389 women in 12 studies whose RBC folate concentrations were available, significantly lower folate status was observed among oral contraceptive users (mean reduction 59.32 µg/L; 95% CI 58.03 to 23.04, P < 0.001).

CONCLUSION

Because of the reduction in blood folate concentrations associated with the use of oral contraceptives, it is critical for women of childbearing age to continue folate supplementation during oral contraceptive use.