Tiered Maternal Anemia Intervention

Abbreviations

Abbreviation	Definition
BEP	Balanced Energy Protein
DFS	Double Fortified Salt
MMS	Multiple Micronutrient Supplement
IFA	Iron-folic Acid
ANC	Antenatal Care
BMI	Body Mass Index
PLW	Pregnant and Lactating Women
LMICs	Low- and Middle-Income Countries
Focal countries	Pakistan, Bangladesh, Nigeria, Malawi

Intervention Overview

Tiered maternal anemia intervention is an integrated life course intervention designed for at-risk female popualtion (e.g., women during pregnancy, women of reprodictive age, etc.) for averting the burden of maternal anemia in LMICs. It consists of three tiers: 1) Large-scale food fortificaiton (DFS), 2) Supplmentation (BEP and MMS), and 3) treatment (IV iron).

The scope of our simulation work is to estimate following measures in 4 focal countries:

• the size of eligible population at risk for each tier of the pyramid;

• the burden of the maternal anemia in terms of deaths and DALYs occurring in the population at risk within each tier of the pyramid if we assume intervention is not applicable;

• the impact at each tier on maternal anemia in terms of averted deaths and DALYs if we assume complete pyramid of interventions are applied.

Tiered Intervention

Tier	Intervention	Product name	Product definition	Target population	Note
1	Large-scale food fortification	DFS		Women of reproductive age (15 to 49 years)
2	Supplementation	BEP		PLW at ANC service with BMI less than 18.5
2	Supplementation	MMS		PLW at ANC service with BMI greater than or equal to 18.5
3	Treatment	IV iron		Pregnant women in 2nd/3rd trimester with moderate/severe anemia referred from ANC to higher level facility

Todo

Fill out the table above with intervention product definition.

Affected Outcomes

Outcome	Effect	Population	Note
Population mean hemoglobin	Additive	General population/PLW/anemic PLW	LSFF/supplementation/treatment effect sizes and target populations vary. Hemoglobin shift affects both anemia and maternal mortality

Baseline Coverage Data

Todo

Document intervention coverage for eligible population

Baseline coverage data

Location	Subpopulation	Coverage parameter	Value	Note
Bangladesh
Malawi
Nigeria
Pakistan

Vivarium Modeling Strategy

Warning

This document summarizes the modeling strategy to calculate the impact of these interventions among PLW for a multiplication model. For the Vivarium microsimulation modeling strategy of the maternal supplementation strategy on maternal hemoglobin levels, see this document.

Hemoglobin

How to model hemoglobin exposure in Vivarium:

1. Construct hemoglobin distributions for each location-/age-/population- subgroup

2. Apply pregnancy adjustment factor to hemoglobin distributions for pregnant and general populations

3. Modify hemoglobin distributions based on intervention effects

The hemoglobin model in GBD 2019 can be found Here.

Modeled Outcomes

Outcome	Outcome type	Outcome ID	Affected measure	Effect size measure	Effect size	Note
Hemoglobin	MEID	10487	Mean hemoglobin concentration	Risk difference	Detailed in table Effect Size

Restrictions

Restriction	Value	Note
Male only	False
Female only	True
Age group start	15 years (ID 8)
Age group end	49 years (ID 14)

Note

Reproductive age is defined as 10 to 54 years in GBD, we trimmed it for this project by request of BMGF.

Effect Size

Intervention	Effect size	Relative to	Effect size Label
DFS	3.3 (95%CI 1.8-4.8)	No DFS intervention	A
MMS (or IFA)	7.8 (95%CI 4.08-11.52)	No iron in pregnancy	B
BEP	3.7 (95%CI 1.9-5.6)	IFA	C
IV iron	23 (95%CI TBD)	No IV iron intervention	D

Changes in population hemoglobin

Tier	Addition to non-PLW population hemoglobin	Addition to PLW population hemoglobin
1	\(+ A\)	\(+ A\)
2	\(+ A\)	\(+ A + P_{anc1} * [P_{underweight} * (P_{IFA} * C + (1 - P_{IFA}) * (B + C)) + (1 - P_{underweight}) * (1 - P_{IFA}) * B]\)
3	\(+ A\)	Average of \(+ A + P_{anc1} * [P_{underweight} * (P_{IFA} * C + (1 - P_{IFA}) * (B + C)) + (1 - P_{underweight}) * (1 - P_{IFA}) * B + P_{low\; hb} * D]\) and \(+ A + P_{anc1} * [(1 - P_{low\; hb}) * (P_{underweight} * (P_{IFA} * C + (1 - P_{IFA}) * (B + C)) + (1 - P_{underweight}) * (1 - P_{IFA}) * B) + P_{low\; hb} * D]\)

Where,

• \(P_{anc1}\) = proportion of pregnant women have one time antenatal care visit within a year

• \(P_{underweight}\) = proportion of pregnant women with BMI less than 18.5 kg/m^2

• \(P_{IFA}\) = proportion of pregnant women have already received iron-folic acid

• \(P_{low\; hb}\) = proportion of pregnant women with hemoglobin concentrations less than 100 g/L

Objective 1: Eligible population sizes

Equations

Population description	Calculation
Women of reproductive age (15 to 49 years)	\(pop\)
PLW at ANC	\(pop * (asfr + sbr) * P_{anc1}\)
Pregnant women in 2nd/3rd trimester with moderate/severe anemia referred from ANC to higher level facility	\(pop * (asfr + sbr) * P_{anc1} * P_{low\; hb}\)

Where,

• \(pop\) = GBD 2019 population size of female aged 15 to 49 years

• \(P_{asfr}\) = GBD 2019 age-specific fertility rate, pulled using get_covariate_estimates with covariate_id = 13

• \(P_{sbr}\) = GBD 2019 still birth rate (still birth to live birth ratio), pulled using get_covariate_estimates with covariate_id = 2267

• \(P_{anc1}\) = proportion of pregnant women have one time antenatal care visit within a year, pulled using get_covariate_estimates with covariate_id = 7

• \(P_{low\; hb}\) = proportion of pregnant women with hemoglobin concentrations less than 100 g/L

Objective 2: Anemia and Maternal Disorders Burden

Effects of hemoglobin on anemia and maternal disorders can be found here.

Assumptions and Limitations

Validation and Verification Criteria

References