A cost-effectiveness analysis of folic acid fortification policy in the United States

Abstract

Objective: To quantify the health and economic outcomes associated with changes in folic acid consumption following the fortification of enriched grain products in the USA.

Design: Cost-effectiveness analysis.

Setting: Annual burden of disease, quality-adjusted life years (QALY) and costs were projected for four steady-state strategies: no fortification, or fortifying with 140, 350 or 700 microg folic acid per 100 g enriched grain. The analysis considered four health outcomes: neural tube defects (NTD), myocardial infarctions (MI), colon cancers and B12 deficiency maskings.

Subjects: The US adult population subgroups defined by age, gender and race/ethnicity, with folate intake distributions from the National Health and Nutrition Examination Surveys (1988-1992 and 1999-2000), and reference sources for disease incidence, utility and economic estimates.

Results: The greatest benefits from fortification were predicted in MI prevention, with 16 862 and 88 172 cases averted per year in steady state for the 140 and 700 microg fortification levels, respectively. These projections were between 6261 and 38 805 for colon cancer and 182 and 1423 for NTD, while 15-820 additional B12 cases were predicted. Compared with no fortification, all post-fortification strategies provided QALY gains and cost savings for all subgroups, with predicted population benefits of 266 649 QALY gained and $3.6 billion saved in the long run by changing the fortification level from 140 microg/100 g enriched grain to 700 microg/100 g.

Conclusions: The present study indicates that the health and economic gains of folic acid fortification far outweigh the losses for the US population, and that increasing the level of fortification deserves further consideration to maximise net gains.

Figure 1

Daily total folate intake distributions pre-versus-post fortification by gender and race/ethnicity, corrected for measurement error. Reprinted with permission from the American Public Health Association from Bentley TGK, Willett WC, Weinstein WC, and Kuntz KM. Population-Level Changes in Folate Intake by Age, Gender, and Race/Ethnicity after Folic Acid Fortification. Am J Public Health.96:2040-2047.

Figure 2

Percent decline in annual incidence of neural tube defects (Panel a), myocardial infarctions (Panel b), and colon cancers (Panel c) after folic acid fortification, by age, gender, race/ethnicity, and fortification strategy.

Figure 2

Percent decline in annual incidence of neural tube defects (Panel a), myocardial infarctions (Panel b), and colon cancers (Panel c) after folic acid fortification, by age, gender, race/ethnicity, and fortification strategy.

Figure 2

Percent decline in annual incidence of neural tube defects (Panel a), myocardial infarctions (Panel b), and colon cancers (Panel c) after folic acid fortification, by age, gender, race/ethnicity, and fortification strategy.

Figure 3

Dose-response assumptions used in sensitivity analyses for neural tube defects (NTDs, Panel a) and myocardial infarctions (MIs, Panel b). Risk is relative to an average folate intake of <200 micrograms (mcg) per day.