Conflicting effects of BMI and waist circumference on iron status

Association between adiposity and iron status in women of reproductive age: data from the UK National Diet and Nutrition Survey 2008-2019 (NDNS)

BACKGROUND

Overweight/obesity and iron deficiency are highly prevalent in women of reproductive age (WRA), impacting on women's health. Obesity is a risk factor for nutritional deficiencies but its association with iron deficiency is unclear.

OBJECTIVE

To determine the association between adiposity and markers of iron status and iron deficiency prevalence in WRA.

METHODS

This cross-sectional study analyzed the National Diet and Nutrition Survey (NDNS, 2008-2019) data, focusing on women aged 18-49y with BMI ≥18.5 kg/m2. Prevalence of anemia, Iron Deficiency Anemia (IDA), and Iron Deficiency (ID) were analyzed. Ferritin was adjusted for C-reactive protein. Iron status was assessed across high and low BMI, waist circumference (WC), waist-to-height (WHtR), and waist-to-hip ratio (WHR). Chi2, linear and logistic regression were performed adjusting for covariates.

RESULTS

Among 1,098 WRA, 496 normal weight and 602 overweight/obesity, prevalence rates were: anemia 9.2% and IDA 6.8%. Anemia was more prevalent in those with higher WHtR and WHR (11.9% vs 5.9% and 16.7% vs 6.5%, both p<0.001). WRA with increased WC, WHtR, and WHR had higher IDA prevalence than those with lower adiposity. (8.5% vs 4.3%, p=0.005; 9.4% vs 3.3%, p<0.001; 12.1% vs 4.9%, p<0.001). ID prevalence was 49.7% (ferritin cut-off 30 μg/L) and 19.6% (ferritin cut-off 15 μg/L), showing similar rates across adiposity groups. ID prevalence defined by soluble transferrin receptor (sTfR) was higher in women with increased WHR (p=0.001). Higher WHR predicted ID categorized by sTfR (aOR 2.104, p=0.004), and WHtR and WHR predicted anemia and IDA (anemia: WHtR aOR 2.006 p=0.036; WHR aOR 4.489 p<0.001; IDA: WHtR: aOR 2.942, p=0.012; WHR aOR 4.142, p<0.001).

CONCLUSIONS

At least one in five WRA in the UK are iron deficient, highlighting the need to revise current policies. Greater central adiposity was strongly associated with impaired iron status and the development of anemia, IDA, and ID.

Micronutrient Patterns and Low Intake of Vitamin A, Vitamin D, Folate, Magnesium, and Potassium Among Prediabetes and Type 2 Diabetes Patients

Background Assessing micronutrient intake is important in identifying deficiencies that may contribute to insulin resistance, poor glycemic control, and increased risk of diabetes-related complications. The study's objectives were to evaluate micronutrient intake in prediabetes (PD) and type 2 diabetes (T2DM) patients compared to recommended dietary intakes (RDI) and to determine the associations between the micronutrient patterns and both anthropometric measurements and biomarkers of diabetes. Methods This cross-sectional study was conducted on 349 patients with T2DM and 252 patients with PD. Micronutrient intake was evaluated using a validated food frequency questionnaire. Micronutrient patterns were extracted from factor analysis using principal component analysis with varimax rotation. Participants in the highest tertile were considered to have the highest adherence to the corresponding micronutrient pattern. Results T2DM patients had a significantly lower intake of vitamin E (9.4 ± 0.2 vs. 10.1 ± 0.3 mg; p = 0.048), vitamin D (44.3 ± 1.1 vs. 48.9 ± 1.7 IU; p = 0.020), and thiamin (1.3 ± 0.1 vs. 1.4 ± 0.1 mg; p = 0.013) compared to PD patients. All patients had a significantly lower intake of vitamin A, vitamin D, folate, magnesium, and potassium and a significantly higher intake of vitamin B12 and copper compared to RDI. Three distinct micronutrient patterns were identified within each group. In the PD group, the Fe-Mn-Se pattern correlated significantly with waist circumference (WC) and fasting plasma glucose (FPG). The Vit.C-K-Folate pattern showed significant associations with body fat (BF). The Vit.B2-P-Vit.B12 pattern was significantly linked to WC, body mass index (BMI), BF, FPG, and serum insulin (SI). For the T2DM patients, the K-Folate-Mg pattern displayed an inverse and significant association with weight and WC. The Iron-Se-Vit.B3 pattern showed a significant association with low-density lipoprotein (LDL) cholesterol, triglycerides, and total cholesterol. The Vit.B2-P-Ca pattern was significantly associated with fasting plasma glucose (FPG). Conclusion This study demonstrated that T2DM patients had significantly lower vitamin E, vitamin D, and thiamin intake than PD patients. Both T2DM and PD patients had a significantly lower intake of vitamin A, vitamin D, folate, magnesium, and potassium compared to the RDI. Among the identified micronutrient patterns, only the K-Folate-Mg pattern exhibited a significant association with reduced body weight and WC.

The association between lipid profile, oxidized LDL and the components of metabolic syndrome with serum mineral status and kidney function in individuals with obesity

BACKGROUND

Metabolic syndrome (MetS) is presented with a cluster of cardio-metabolic risk factors with widespread prevalence. In the present case-control study, we aimed to examine the relationship between several minerals and renal function tests with the components of MetS in individuals with obesity.

METHODS

This study included 127 individuals with obesity of both gender with or without MetS as the case and control, respectively. MetS was characterized based on the Adult Treatment Panel III (ATP III) criteria. Anthropometric variables and blood pressure were recorded. Mineral status including serum magnesium, copper, calcium, phosphorous, and iron were measured using standard colorimetric methods. Also, the serum lipid levels, concentrations of oxidized low-density lipoprotein (Ox-LDL), and renal function tests, including total protein, albumin, urea, creatinine, and uric acid were evaluated using commercial enzyme-linked immunosorbent assay (ELISA) kits.

RESULTS

According to our results, individuals with obesity and MetS had higher levels of waist circumference (WC) and diastolic blood pressure (P < 0.05) compared to individuals with obesity and without MetS. Moreover, individuals with obesity and MetS had higher levels of serum total cholesterol (TC), triglyceride (TG), insulin, and iron (P < 0.05). In individuals with obesity and MetS, iron and albumin showed a positive relationship with LDL cholesterol and TG concentrations, respectively (P < 0.05 for all of them). Also, there was a positive association between serum magnesium and Ox- LDL in individuals with obesity with MetS. While, in individuals with obesity and without MetS, only a positive association between urea and uric acid with WC was observed (P < 0.05).

CONCLUSION

Our results suggest that disturbed serum lipids in obesity-metabolic syndrome is associated with homeostatic changes in the level of minerals or proteins that are involved in their metabolism. Although, further studies are needed to better explain and clarify the underlying mechanism of observed relationships.

Iron status and obesity-related traits: A two-sample bidirectional Mendelian randomization study

BACKGROUND

The association between iron status and obesity-related traits is well established by observational studies, but the causality is uncertain. In this study, we performed a two-sample bidirectional Mendelian randomization analysis to investigate the causal link between iron status and obesity-related traits.

METHODS

The genetic instruments strongly associated with body mass index (BMI), waist-hip ratio (WHR), serum ferritin, serum iron, transferrin saturation (TSAT), and total iron-binding capacity (TIBC) were obtained through a series of screening processes from summary data of genome-wide association studies (GWAS) of European individuals. We used numerous MR analytical methods, such as inverse-variance weighting (IVW), MR-Egger, weighted median, and maximum likelihood to make the conclusions more robust and credible, and alternate methods, including the MR-Egger intercept test, Cochran's Q test, and leave-one-out analysis to evaluate the horizontal pleiotropy and heterogeneities. In addition, the MR-PRESSO and RadialMR methods were utilized to identify and remove outliers, eventually achieving reduced heterogeneity and horizontal pleiotropy.

RESULTS

The results of IVW analysis indicated that genetically predicted BMI was associated with increased levels of serum ferritin (β: 0.077, 95% CI: 0.038, 0.116, P=1.18E-04) and decreased levels of serum iron (β: -0.066, 95% CI: -0.106, -0.026, P=0.001) and TSAT (β: -0.080, 95% CI: -0.124, -0.037, P=3.08E-04), but not associated with the levels of TIBC. However, the genetically predicted WHR was not associated with iron status. Genetically predicted iron status were not associated with BMI and WHR.

CONCLUSIONS

In European individuals, BMI may be the causative factor of serum ferritin, serum iron, and TSAT, but the iron status does not cause changes in BMI or WHR.

Impact of resistance training and basic ferritin on hepcidin, iron status and some inflammatory markers in overweight/obese girls

BACKGROUND

Exercise can reduce hepcidin, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 and improve the iron status, but the intensity of exercises is very important. This study will compare the effect of resistance training (RT) intensity on hepcidin levels, iron status, and inflammatory markers in overweight/obese girls with and without iron stores deficient.

MATERIALS AND METHODS

In this quasi-experimental study, 40 students of the University of Isfahan (18-22-year old, with 35 > body mass index [BMI] ≥25) voluntarily participated in the study. Participants were divided into two groups with 20 participants, based on serum ferritin (>30 ng/ml or ≤30 ng/ml). Participants in each group were randomly and equally assigned to one of the moderate or high-intensity training groups. RT was performed 8 weeks, 4 days a week, and each session for 1 h, with an elastic band. The iron levels, hepcidin, total iron-binding capacity, ferritin, hemoglobin, TNF-α, and IL-6 before and after intervention were collected with the blood samples. Two-way analysis of variance was used to assess the impact of exercise and ferritin level and their interaction, and the paired test was utilized for test changes from baseline.

RESULTS

There are no significant interactions between ferritin levels and exercise intensity for the main outcomes (all P > 0.05). The significant impact of the mode of exercise was observed in TNF-α (P < 0.05), and a significant difference between low and high levels of ferritin was observed in hepcidin (P = 0.002). Besides, in all four groups, significant decreases were observed in BMI (28.00 ± 3.00 to 27.00 ± 3.00), hepcidin (1234.02 ± 467.00 to 962.06 ± 254.00), and TNF-α (223.00 ± 99.00 to 174.00 ± 77.00) compared to the baseline measurements (all P < 0.05).

CONCLUSION

Basal ferritin levels appear to be effective on hepcidin levels, TNF-α, and IL-6 after the intervention. RT with two different intense can reduce BMI, hepcidin, ferritin, and TNF-α in all groups. It seems that performing RT reduces inflammation and hepcidin in obese/overweight participants with different iron stores.

Undiagnosed Hypertension in a Workplace: The Case of a Logistics Company in Gauteng, South Africa

A large proportion of the population with hypertension remains undiagnosed, untreated, or inadequately treated, contributing to the rising burden of cardiovascular diseases in South Africa. A workplace may either mitigate or accentuate the risk factors for hypertension. A cross sectional study was conducted to determine the prevalence of undiagnosed hypertension and associated factors among 312 employees in a Logistics Company, South Africa. A modified, validated, self-administered WHO STEPwise questionnaire was used to collect data on demography, lifestyle factors, anthropometry and blood pressure (BP). Hypertension was defined at BP ≥ 140/90 mmHg. Data was analysed using STATA 14. Mean age of employees was 40 ± 10 years, with a 50% prevalence of undiagnosed hypertension. No significant association was observed between occupation and undiagnosed hypertension, except for high prevalence of undiagnosed hypertension among truck drivers and van assistants (43%), and general workers (27%), having higher odds of increased waist-to-height ratio. Hypertension was associated with age (OR = 2.3, 95%CI; 1.21–4.27), alcohol use (AOR = 1.8, 95%CI; 1.05–2.93), waist circumference (AOR = 2.3, 95%CI; 1.29–4.07) and waist-to-height-ratio (AOR = 3.7, 95%CI; 1.85–7.30). Improved and effective workplace health programs and policies are necessary for management of undiagnosed hypertension among employees. Longitudinal studies on mediation of occupation in association of demographic and lifestyle factors with hypertension in workplaces are needed.

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.

Association of Metabolic Syndrome and Hyperferritinemia in Patients at Cardiovascular Risk

AIM

To evaluate the association between parameters of hyperferritinemia (HF) and metabolic syndrome (MS) in patients at cardiovascular risk.

PATIENTS AND METHODS

This is a cross-sectional analytical observational study that included 269 patients who attended a cardiology unit. Biochemical and anthropometric parameters were evaluated to identify the presence of HF and MS. The presence of MS was evaluated according to NCEP ATP III. Biochemical parameters (glycemia, triglycerides, HDL-c) were assessed according to the manufacturer's protocols. Anthropometric measurements and blood pressure measurements were made by a trained professional. The chi-square (X ²) test, odds ratio, normality distribution (verified by the Kolmogorov-Smirnov test), and Levene's test were used to analyze the variables. To evaluate the effect of MS, HF, and the interaction between MS and HF, two-way analysis of variance (ANOVA) was performed based on the homogeneity of the variances, followed by Bonferroni's post hoc comparisons. Spearman correlation analysis was performed to evaluate the relationship between quantitative variables. A multiple linear regression model was used to analyze the effect of covariables. A logistic regression model was built to analyze the variables that contribute significantly to predict the outcome (HF) using the backward method.

RESULTS

Our results showed that 57% of men and 49.5% of women presented with MS; 44% of men and 11% of women presented with HF. The presence of MS and hypertriglyceridemia increase the probability of having HF by up to 2.1 and 1.88 times, respectively, while for male sex it is increased by 6.2 times. Patients with HF have higher values of C-reactive protein, ferritin, and transferrin saturation, regardless of the presence of MS. The linear regression analysis model indicated that the variables considered in this study explain less than 30% of the variation in ferritin and that the presence of MS in men is responsible for 22% of the variation in the probability of the occurrence of HF.

CONCLUSION

Our results show that hyperferritinemia is closely associated with the components of MS (positive correlation with glycemia, triglycerides levels, blood pressure, and waist circumference, and negative correlation with HDL-c values) in the studied population.

The double burden of malnutrition in a rural health and demographic surveillance system site in South Africa: a study of primary schoolchildren and their mothers

BACKGROUND

In South Africa, the occurrence of the double burden of malnutrition is on the rise at a household level predisposing children and their mothers to negative health outcomes. However, few studies have been conducted at a household level. Therefore, we studied a double burden of malnutrition using child-mother pairs in a rural setting.

METHODS

A cross-sectional quantitative survey was conducted among 508 child-mother pairs selected from primary schools using a multistage sampling in a rural Dikgale Health and Demographic Site in Limpopo Province, South Africa. Anthropometric measurements of children and mothers, and socio-demographic data were collected. WHO AnthroPlus was used to generate body-mass-index z-scores of children and the BMI was used to indicate overweight and obesity among the mothers. Mann Whitney test was used to compare the means of variables between sexes and age groups, while the prevalence of thinness and overweight/obesity were compared using a chi-square. Multivariate logistic regression with a stepwise backward elimination procedure, controlling for confounding, was used to determine the association between the thinness and overweight/obesity and the covariates.

RESULTS

Twenty five percent (25%) of the children were thin, 4% were overweight and 1% obese, while mothers were overweight (27.4%) and 42.3% obesity (42.3%) were observed among the mothers. The odds of being thin were higher in boys than in girls (AOR = 1.53, 95%CI: 1.01-2.35). Overweight/obese mothers were more likely to have thin children (AOR = 1.48, 95% CI: 1.01-2.18) and less likely to have overweight/obese children (AOR = 0.18, 95%CI: 0.07-0.46).

CONCLUSION

A double burden of malnutrition was observed on a household level with thinness among children and overweight/obesity among mothers. A need to address the dual problems of undernutrition and rapidly rising trends of overweight/obesity cannot be over-emphasized.

Iron status in the elderly: A review of recent evidence

A comprehensive literature review of iron status in the elderly was undertaken in order to update a previous review (Fairweather-Tait et al, 2014); 138 summarised papers describe research on the magnitude of the problem, aetiology and age-related physiological changes that may affect iron status, novel strategies for assessing iron status with concurrent health conditions, hepcidin, lifestyle factors, iron supplements, iron status and health outcomes (bone mineral density, frailty, inflammatory bowel disease, kidney failure, cancer, cardiovascular, and neurodegenerative diseases). Each section of this review concludes with key points from the relevant papers. The overall findings were that disturbed iron metabolism plays a major role in a large number of conditions associated with old age. Correction of iron deficiency/overload may improve disease prognosis, but diagnosis of iron deficiency requires appropriate cut-offs for biomarkers of iron status in elderly men and women to be agreed. Iron deficiency (with or without anemia), anemia of inflammation, and anemia of chronic disease are all widespread in the elderly and, once identified, should be investigated further as they are often indicative of underlying disease. Management options should be reviewed and updated, and novel therapies, which show potential for treating anemia of inflammation or chronic disease, should be considered.

Prevalence of thyroid autoimmunity and dysfunction in women with iron deficiency during early pregnancy: is it altered?

OBJECTIVE

Thyroid disorders and iron deficiency (ID) are associated with obstetrical and fetal complications. Iron is essential for the normal functioning of thyroid peroxidase (TPO-abs) and ID is frequent during pregnancy. The aim of this study was to compare the prevalence of thyroid autoimmunity (TAI) and dysfunction during the first trimester of pregnancy in women with and without ID.

DESIGN

Cross-sectional data analysis of 1900 pregnant women nested within an ongoing prospective collection of pregnant women's data.

METHOD

The study was performed in a single, tertiary referral center. During the first antenatal visit, ferritin, TPO-abs, thyroid-stimulating hormone (TSH) and free T4 (FT4) were measured and age and BMI were recorded. ID was defined as ferritin <15µg/L, TAI when TPO-abs was >60kIU/L, and subclinical hypothyroidism (SCH) when TSH was >2.5mIU/L.

RESULTS

ID was present in 35% of women. Age and BMI were comparable between both groups. In the ID group, the prevalence of TAI and SCH was significantly higher, compared with that in the non-ID group (10% vs 6% and 20% vs 16%; P=0.011 and 0.049 respectively). Ferritin was inversely correlated with serum TSH (ρ=-0.076; P=0.001) and positive with FT4 levels (ρ=0.112; P<0.001). In the logistic regression model, ID remained associated with TAI after correction for confounding factors (P=0.017). The association with SCH was absent after correction for the confounders in the logistic regression model (P=0.082), but remained present in the linear regression model (P=0.035).

CONCLUSIONS

ID was frequent during the first trimester of pregnancy and was associated with a higher prevalence of TAI, higher serum TSH, and lower FT4 levels.

Anemia Status in Relation to Body Mass Index Among Women of Childbearing Age in Bangladesh

Undernutrition and micronutrient deficiency disorders together constitute a major public health concern in Bangladesh. Among many vitamin and mineral deficiency diseases, iron-deficiency anemia remains the most persistent and has been shown to contribute to high maternal and child morbidity and mortality in the country. In parallel with micronutrient malnutrition, the country is also experiencing a rising epidemic of overweight and obesity due to changing pattern in dietary behavior and body mass index status. Previous empirical studies have demonstrated a strong correlation between body weight and anemia status. However, results remain inconclusive and for Bangladesh such evidence is nonexistent. To this end, we conducted this study using Bangladesh Demographic and Health Survey 2011 data with an aim to explore the association between body mass index and anemia status among adult women in Bangladesh. According to the findings, age between 15 and 29 years ( P < .001, OR = 1.30, 95% CI = 1.12-1.49), experiencing first birth before reaching the age of 18 years ( P < .001, OR = 1.31, 95% CI = 1.15-1.50), lack of access to potable water ( P = .013, OR = 1.467, 95%CI = 1.085- 1.982), being underweight ( P < .001, 95% CI = 1.208-1.570) and normal weight ( P < .001, 95% CI = 1.819-2.516) were significantly associated with anemia status.