The Relationship Between Iron Status and Adiposity in Women from Developing Countries: A Review

Correlation of Anemia Due to Poor Iron Status With Obesity at King Fahad Medical City, Riyadh, Saudi Arabia

Background Saudi Arabia has a high prevalence of chronic diseases such as obesity. Moreover, iron deficiency anemia (IDA) in developing countries is the most prevalent type of anemia. This study aims to assess the correlation between anemia related to poor iron status and obesity. Methods A cross-sectional observational study was conducted at the obesity center in King Fahad Medical City, Saudi Arabia, from April to September 2020. Two hundred and forty participants were needed to be included in the study. The data was gathered by utilizing a designed data collection form. Socio-demographic data, weight and height, questions related to the history of anemia, and gynecological data (for females) were collected. The data was analyzed using SPSS (Statistical Package for Social Science) version 28.0. Descriptive statistics were used to present numerical and categorical data and a Chi-square test was conducted to assess the correlation between categorical variables. Informed written consent was obtained from all participants and ethical approval was obtained from the Ethical Board Committee in King Fahad Medical City. Results The study included 240 participants. Two-thirds of the study population are females (64.6%), 66.7% are married, and 65.8% have obesity. Almost one-half of the study population (46%, N=128) was diagnosed with IDA with malnourishment being the most common reason for IDA (88.2%). The results indicated a correlation between obesity and the prevalence of IDA. The prevalence of IDA among participants with obesity (60.4%) was significantly higher compared to non-obese participants (39.5%), p=0.002. The study found that females and underweight individuals have a higher prevalence of IDA (p<0.001). Conclusion Results of the present study suggest that obesity could be associated with a risk of IDA. In addition, Saudi women could be more prone to IDA than men. Further prospective controlled studies among diverse populations in Saudi Arabia including laboratory assessment of inflammatory markers and iron status are required to better understand the correlation between obesity and IDA.

Excess adiposity and iron-deficient status in Colombian women of reproductive age

OBJECTIVE

Information about excess adiposity markers different from BMI and iron status is limited and more so about the shape of these associations. This study evaluated the relationship between three adiposity markers and iron-deficient status in reproductive-age women.

METHODS

Cross-sectional analysis in 6357 non-pregnant women from the Colombian nutritional health survey (ENSIN) 2010. Exposures were the following: waist circumference (WC), waist-to-height ratio (W-HtR), BMI, and WC > 80 cm, W-HtR > 0.5, and BMI ≥ 25 and ≥30. Outcomes were the following: iron deficiency (ID) as serum ferritin <15 μg/L, ID as ferritin <30 μg/L, anemia, and continuous values of ferritin and hemoglobin. Logistic and linear regressions adjusted for sociodemographic/inflammation covariates were conducted.

RESULTS

All the adiposity markers, continuous or categorical, were inversely and significantly associated with both ID thresholds in fully adjusted models (p < 0.05). W-HtR reported stronger effect estimates for ID (odds ratios < 0.5) and for prediction of log-ferritin levels (fully adjusted β-coefficient [95% CI] 0.61 [0.39-0.82], p < 0.01) and was also inversely associated with anemia (p < 0.05). In cubic splines analyses, W-HtR, WC, and BMI were linearly associated with ID from values closer to international thresholds of general or central obesity, and the patterns of WC and BMI tended toward flatness. A significant decline in the likelihood of anemia was steeper by increasing W-HtR than by increasing BMI. After exclusion of women with C reactive protein >  5 mg/L or adjustment for C reactive protein, adiposity markers remained significantly related to ferritin levels and W-HtR with anemia.

CONCLUSIONS

Women with higher adiposity were less likely to have an iron-deficient status. W-HtR was the strongest and most consistently associated marker. Inflammation would not be involved in the associations found.

The Relationship Between Ferritin and BMI is Mediated by Inflammation Among Women in Higher-Income Countries, But Not in Most Lower-Income Countries Nor Among Young Children: A Multi-Country Analysis

Background

In the presence of inflammation, the serum or plasma ferritin concentration ("ferritin" hereafter) transiently increases, confounding its interpretation as an iron status marker. The extent to which adiposity-related inflammation may influence ferritin interpretation is uncertain.

Objectives

We describe relationships between weight status, inflammation, and ferritin among nonpregnant women of reproductive age (WRA; 15-49 years) and preschool-age children (PSC; 6-59 months) with normal weight to overweight or obesity (OWOB) in differing geographic settings.

Methods

Cross-sectional data were separately analyzed from 18 surveys (WRA) and 25 surveys (PSC) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project, excluding observations with underweight, wasting, pregnancy, or malaria. Relationships were assessed between BMI (in WRA) or BMI-for-age z-score (BAZ; in PSC), inflammatory biomarkers of C-reactive protein (CRP) and/or α-1-acid glycoprotein (AGP), ferritin by linear regression, and potential mediation by CRP and/or AGP in relationships between BMI or BAZ and ferritin with structural equation modeling. Regression and mediation models accounted for complex survey designs. Results were grouped by World Bank income classifications.

Results

In 5 of 6 surveys among WRA from upper-middle and high-income countries, ferritin was significantly positively associated with BMI, and this relationship was partially (or fully, in the United States) mediated by CRP and/or AGP. Mediation was present in 4 of 12 surveys for WRA in low- and lower-middle income countries. Among PSC, ferritin was positively associated with CRP and/or AGP in all surveys, but there were no significant CRP- or AGP-mediated relationships between ferritin and BAZ, except a negative relationship in the Philippines.

Conclusions

Where having OWOB is common among WRA, measurements of inflammatory biomarkers and their uses in interpreting ferritin may improve iron status assessments. While these relationships were inconsistent among PSC, inflammation was common and should be measured to interpret iron status. Included Kenyan trial data are registered at clinicaltrials.gov as NCT01088958.

A Cross-sectional Study of Iron Deficiency Anemia and Hemoglobinopathy Carriers among School Children in Two Different Cities in KSA

Aim: Iron deficiency anemia (IDA) is the most common cause of anemia in the Kingdom of Saudi Arabia. Thalassemia and sickle cell disease (SCD) are major concerns in several nations, including KSA. This study sought to investigate the prevalence of IDA, sickle cell trait (SCT), and B thalassemia trait (BTT) among school children in Al-Khobar and Makkah, Saudi Arabia. Methods: A multistage random sample of 570 school children aged 12–18 years from both cities were educated about these illnesses and tested for CBC, serum iron, TIBC, reticulocytosis, and sickling. In some circumstances, hemoglobin electrophoresis and HPLC were used. Results: Overall, 13% of people had IDA, 3.2 percent had SCT, and 2.5 percent had BTT. The hematological parameters of students with IDA and BTT differed significantly from those of normal students in each city, but not between normal students and those with SCT. There were no significant differences between the sexes for all blood parameters except iron and TIBC. Conclusion: Strengthening public health education, dietary initiatives, and school-based hemoglobinopathy carrier screening is proposed to help detect anemia early.

Association between obesity and iron deficiency (Review)

Obesity is a risk factor for several comorbidities and complications, including iron deficiency anemia. Iron deficiency anemia is a serious global public health problem, with a worldwide prevalence. The high prevalence of obesity in combination with iron deficiency incidence observed in different age and sex categories suggests an association between obesity and iron status. Obesity may disrupt iron homeostasis, resulting in iron deficiency anemia. The association between obesity and iron deficiency may be due to increased hepcidin levels mediated by chronic inflammation. Hepcidin is a small peptide hormone that functions as a negative regulator of intestinal iron absorption. Significant body weight loss in overweight and obese individuals decreases chronic inflammation and serum hepcidin levels, resulting in improved iron status due to increased iron absorption. However, further randomized controlled trials are required to confirm this effect.

H. Shehada A, Abdelnasser AbouHassanein E, Moawad J, Bawadi H, Shi Z. Association between central obesity indices and iron status indicators among Qatari adults

Co-existence of iron deficiency and obesity in adults has been reported in many countries. However, little is known on the association between obesity and iron deficiency in Qatar. This study aimed to investigate the link between abdominal obesity indices and iron status among adults in Qatar. A random sample of 1000 healthy Qatari adults, aged 20-50 years, was obtained from Qatar Biobank study. Body weight, waist circumference, dual x-ray absorptiometry (DXA) parameters and iron status indicators were measured using standard techniques. Multiple regression analysis was used to examine the associations. The prevalence of iron deficiency and anaemia were 35.4 and 25%, respectively. Of the participants with a large waist circumference, 31.7% had anaemia. Ferritin significantly increased with the increase in the android fat to gynoid fat ratio and visceral fat in both genders. Serum iron and transferring saturation decreased significantly with the increase in waist circumference in women. In both genders, C-reactive protein increased with the increase in all obesity indices. Standardized values of waist circumference, android fat, gynoid fat ratio and visceral fat were significantly associated with log transformed ferritin in men and women. Waist circumference was inversely related to serum iron (β:-0.95, 95% CI:-1.50,-0.39) and transferrin saturation (β:-1.45, 95%CI:-2.46, -0.43) in women. In men, waist circumference was positively associated with haemoglobin level (β: 0.16, 95% CI:0.04, 0.29). Central obesity coexists with anaemia among the study population. Elevated central obesity indices were associated with an increase in ferritin concentration. The increased ferritin concentration may be attributed to the increase in inflammatory status as a result of an increase in c-reactive protein concentration associated with central obesity.

Iron Deficiency and Neuroendocrine Regulators of Basal Metabolism, Body Composition and Energy Expenditure in Rats

Although dietary iron is a determinant of iron status in animals, body fat mass has been reported to have an inverse association with iron status in human studies. The goal of this study was to determine the relationship between Fe homeostasis, body composition, energy expenditure and neuroendocrine regulators for severe Fe-deficiency anaemia. Forty male Wistar albino rats recently weaned were divided at random into two groups: the control group was fed the basal diet, AIN-93G diet (normal-Fe) and the anaemic group received a low-Fe diet for 40 days. Neuroendocrine parameters that regulate basal metabolism and appetite (thyroid hormones, ghrelin, glucose-dependent insulinotropic polypeptide (GIP), glucagon, insulin, adrenocorticotropic hormone and corticosterone), body composition, respiratory volumes, energy expenditure, haematological and biochemical were assessed. Total body fat was lower, whereas lean mass, free and total water were higher in the anemic group. O₂ consumption, CO₂ production, energy expenditure (EE) and respiratory quotient (RQ) were lower in the Fe-deficient animals. Triiodothyronine and thyroxine hormones decreased, while thyroid-stimulating hormone increased in the anemic group. Circulating levels of ghrelin were lower in the anemic group, while GIP, glucagon, insulin, corticosterone and adrenocorticotropic hormone levels were higher. Fe-deficiency impairs weight gain in the rats, with marked reductions in lean mass and body fat, indicating lower energy stores.

Anemia among indigenous women in Brazil: findings from the First National Survey of Indigenous People's Health and Nutrition

BACKGROUND

Anemia is recognized as a major public health problem that disproportionately affects vulnerable populations. Indigenous women of reproductive age in Brazil are thought to be at high risk, but lack of nationwide data limits knowledge about the burden of disease and its main determinants. This study aimed to assess the prevalence of anemia and associated factors in this population using data from The First National Survey of Indigenous People's Health and Nutrition in Brazil.

METHODS

Data were collected from Indigenous women between 15 and 49 years old based on a nationwide sample of villages. The outcomes of interest were hemoglobin levels (g/dL) and anemia (< 12 g/dL for nonpregnant and < 11 g/dL for pregnant women). Multilevel models were used to explore associations with contextual (village) and individual (household/woman) level variables.

RESULTS

Based on data for 6692 Indigenous women, the nationwide mean hemoglobin level was 12.39 g/dL (95% CI: 12.29-12.50). Anemia prevalence was high (33.0%; 95% CI: 30.40-35.61%) and showed pronounced regional disparities. No village-level characteristics were associated with anemia or hemoglobin levels in the multilevel model. Even after controlling for upper level variables, socioeconomic status, parity, body mass index, and having been treated for malaria were associated with anemia and hemoglobin levels.

CONCLUSION

The prevalence of anemia in Brazilian Indigenous women was 12% greater than the national estimates for women of reproductive age. Anemia prevalence and mean hemoglobin levels among Indigenous women appear to be partly explained by some previously recognized risk factors, such as socioeconomic status, body mass index, and malaria; however, part of the variability in these outcomes remains unexplained. Knowledge of health status and its potential determinants is essential to guide public policies aimed at controlling anemia burden in Indigenous communities.

Prevalence and correlates of anaemia in adolescents in Riyadh city, Kingdom of Saudi Arabia

OBJECTIVE

To determine the prevalence and correlates of anaemia in male and female adolescents in Riyadh, Kingdom of Saudi Arabia.

DESIGN

A cross-sectional community-based study.

SETTING

Five primary health-care centres in Riyadh.

SUBJECTS

We invited 203 male and 292 female adolescents aged 13-18 years for interview, anthropometric measurements and complete blood count. Blood Hb was measured with a Coulter Cellular Analysis System using the light scattering method.

RESULTS

Using the WHO cut-off of Hb<12 g/dl, 16·7 % (n 34) of males and 34·2 % (n 100) of females were suffering from anaemia. Mean Hb in males and females was 13·5 (sd 1·4) and 12·3 (sd 1·2) g/dl, respectively. Values for mean cell volume, mean cell Hb, mean corpuscular Hb concentration and red cell distribution width in male and female adolescents were 77·8 (sd 6·2) v. 76·4 (sd 10·3) μm(3), 26·1 (sd 2·7) v. 25·5 (sd 2·6) pg, 32·7 (sd 2·4) v. 32·2 (sd 2·6) g/dl and 13·9 (sd 1·4) v. 13·6 (sd 1·3) %, respectively. Multivariate logistic regression revealed that a positive family history of Fe-deficiency anaemia (OR=4·7; 95 % CI 1·7, 12·2), infrequent intake (OR=3·7; 95 % CI 1·3, 10·0) and never intake of fresh juices (OR=3·5; 95 % CI 1·4, 9·5) and being 13-14 years of age (OR=3·1; 95 % CI 1·2, 9·3) were significantly associated with anaemia in male adolescents; whereas in females, family history of Fe-deficiency anaemia (OR=3·4; 95 % CI 1·5, 7·6), being overweight (OR=3·0; 95 % CI 1·4, 6·1), no intake of fresh juices (OR=2·6; 95 % CI 1·4, 5·1), living in an apartment (OR=2·0; 95 % CI 1·1, 3·8) and living in a small house (OR=2·5; 95 % CI 1·2, 5·3) were significantly associated with anaemia.

CONCLUSIONS

Anaemia is more prevalent among Saudi female adolescents as compared with males. Important factors like positive family history of Fe-deficiency anaemia, overweight, lack of fresh juice intake and low socio-economic status are significantly associated with anaemia in adolescents.

Body mass index, iron absorption and iron status in childbearing age women

BACKGROUND

The prevalence of obesity has increased at an alarming rate worldwide. Some studies have observed an association between iron (Fe) deficiency (ID) and obesity, however more research is needed.

OBJECTIVE

To assess whether body mass index (BMI) is associated with both Fe absorption and Fe status.

METHODS

A cross sectional sample of 318 Chilean childbearing age women was studied. The women received either a single dose of 0.5mg of Fe (n=137, group 1) or 3mg of Fe plus ascorbic acid (1:2 molar ratio) (n=181, group 2), both as FeSO4 with labeled radioisotopes. Fe absorption was assessed through radio Fe erythrocyte incorporation. Fe status was determined by hemoglobin (Hb), mean corpuscular volume, serum Fe, total iron binding capacity, transferrin saturation, erythrocyte Zn protoporphyrin and serum ferritin (SF).

RESULTS

29%, 47% and 24% of the women were classified as normal, overweight or obese, respectively. Fe absorption was significantly lower in obese women (p<0.05). In group 1, the geometric mean and range ±1 SD of the percentage of Fe absorption for normal-weight women was 32.9% vs. 19.7% in obese. For group 2, this percentage was 36% vs. 30%, respectively (2-way ANOVA: BMI classification and Fe dose p<0.05; interaction p=0.34). Although Fe absorption was lower in obese women, they had higher SF (p<0.01) and Hb (p<0.05) concentrations.

CONCLUSION

Although we did not observe a relationship between BMI and Fe status, obese women displayed lower Fe absorption compared with overweight and normal weight women, possibly due to subclinical inflammation associated with obesity.