The iron status of a healthy South African adult population

Nutritional deficiency in South African adults scheduled for bariatric surgery

Background

Globally, there is a rising trend in obesity, known to increase morbidity and mortality. Metabolic surgery and adequate weight loss decrease mortality but may worsen pre-existing nutrient deficiencies. Most data on pre-existing nutritional deficiencies in the population undergoing metabolic surgery is from the developed world, where an extensive micronutrient assessment is achievable. In resource-constrained environments, the cost of a comprehensive micronutrient assessment must be weighed against the prevalence of nutritional deficiencies and the potential harm if one or more nutritional deficiencies are missed.

Methods

This cross-sectional study investigated the prevalence of micronutrient and vitamin deficiencies in participants scheduled to undergo metabolic surgery in Cape Town, South Africa, a low-middle income country. 157 participants were selected and 154 reported on; who underwent a baseline evaluation from 12 July 2017 to 19 July 2020. Laboratory measurements were conducted, including vitamin B12 (Vit B12), 25-hydroxy vitamin D (25(OH)D), folate, parathyroid hormone (PTH), thyroid-stimulating hormone (TSH), thyroxine (T4), ferritin, glycated haemoglobin (HbA1c), magnesium, phosphate, albumin, iron, and calcium.

Results

Participants were predominantly female, aged 45 years (37-51), with a preoperative BMI of 50.4 kg/m2 (44.6-56.5). A total of 64 individuals had Type 2 diabetes mellitus (T2D), with 28 undiagnosed cases at study entry (18% of study population). 25(OH)D deficiency was most prevalent (57%), followed by iron deficiency (44%), and folate deficiency (18%). Other deficiencies (vitamin B12, calcium, magnesium, phosphate) were rarely encountered and affected ≤1% of participants. Folate and 25(OH)D deficiency were related to obesity classification, with a higher prevalence in participants with a BMI ≥40 kg/m2 (p <0.01).

Conclusion

A higher prevalence of some micronutrient deficiencies was noted compared with data from similar populations in the developed world. The minimum baseline/preoperative nutrient evaluation in such populations should include 25(OH)D, iron studies, and folate. Additionally, screening for T2D is recommended. Future efforts should seek to collate broader patient data on a national scale and include longitudinal surveillance after surgery. This may provide a more holistic picture of the relationship between obesity, metabolic surgery and micronutrient status inform more appropriate evidence-based care.

Ferritin and its association with anaemia in a healthy adult population in Kenya

BACKGROUND

Iron deficiency is the commonest cause of anaemia worldwide. Serum ferritin is the most sensitive non-invasive indicator of iron stores but its utility is compromised in inflammatory states as it is an acute phase reactant. This study sought to estimate the burden of iron deficiency in a healthy adult population residing in Kenya and to determine the association between various ferritin cut-offs and anaemia in a population known to have chronic low-grade inflammation.

METHODS

Healthy adults aged 18-65 years were recruited from urban towns in 4 counties in Kenya at average altitudes of 1683-2099m above sea level as part of a global study conducted by the International Federation of Clinical Chemistry (IFCC) to determine reference intervals (RIs) for common laboratory tests. We analyzed complete blood count (CBC), C-reactive protein, iron, transferrin, transferrin saturation and ferritin data.

RESULTS

We obtained data from 528 participants. There were 254 (48.1%) males and 274 females (51.9%). Based on a ferritin cut-off of 15 μg/L and Hb cut-offs of 14.5 g/dL and 12 g/dL, the prevalence of iron deficiency anaemia was 0.8% and 7.3% in males and females respectively. The odds of having anaemia was highest if one had a ferritin value less than 15 μg/L with a sensitivity of 28.6% and specificity of 98.4% in males, and sensitivity of 83.3% and specificity of 78.0% in females.

CONCLUSION

Only the ferritin cut-off of 15 ug/L had an association with anaemia where it can be used for ruling out iron deficiency as the cause. Sex specific ferritin cut-offs for diagnosing iron deficiency in adults in sub-Saharan Africa need to be derived by comparing ferritin levels to stainable iron in bone marrow aspirates and trephines in order to ensure that we are using appropriate clinical decision limits.

Management and outcomes of catatonia: A prospective study in urban South Africa

Objectives

Rapid intervention for catatonia with benzodiazepines and electroconvulsive therapy can prevent fatal complications. We describe the management and treatment response of 44 patients with catatonia in a psychiatric unit in urban South Africa. The objective was to screen admissions for catatonia and investigate management, treatment response, and treatment outcomes.

Method

We used a prospective, descriptive, observational study design and collected data using a data collection sheet, the Bush Francis Catatonia Screening Instrument, the Bush Francis Catatonia Rating Scale, and the Diagnostic Statistical Manual-5 to assess catatonia in new admissions from September 2020 to August 2021.

Results

Of the 241 participants screened on admission, 44 (18.3% of 241) screened positive for catatonia on the Bush Francis Catatonia Screening Instrument, while 197 (81.7% of 241) did not. Thirty-eight (86.4% of 44) received lorazepam, seven (15.9%) received clonazepam, and two (4.6%) received diazepam, implying that three (6.8%) of the 44 participants with catatonia received more than one benzodiazepine sequentially. Ten (22.7% of 44) patients received electroconvulsive therapy. Seven of those treated with electroconvulsive therapy (15.9% of 44 and 70% of 10) responded well and were discharged, whereas 22 (50% of 44 and 64.7% of 34) of those given lorazepam were discharged. Patients treated with electroconvulsive therapy had a higher initial Bush Francis Catatonia Rating Scale score. One patient (2.3%) relapsed within 4 weeks of discharge. Twenty (45.5%) of the 44 patients with catatonia had low average iron levels, 14 (31.8%) had low vitamin B12, and 24 (54.6%) had high creatinine kinase.

Conclusion

Both lorazepam and electroconvulsive therapy were found to be effective treatments for catatonia with good response and outcomes. The length of hospital stay of patients with catatonia was similar to that of patients without catatonia. Treatment guidelines for catatonia need to include the role and timing of electroconvulsive therapy to augment current treatment protocols for the use of lorazepam.

Prevalence of Anaemia, Iron Deficiency, and Iron Deficiency Anaemia in Women of Reproductive Age and Children under 5 Years of Age in South Africa (1997-2021): A Systematic Review

Using a systematic review method, the prevalence of anaemia, iron deficiency (ID), and iron deficiency anaemia (IDA) in women of reproductive age (WRA) and children under 5 years of age was obtained to inform priorities in health planning and policy in South Africa. We searched electronic databases for articles published between 1997 and 2021. A total of 713 articles were identified, of which 14 articles comprising 9649 WRA and 4085 children were included. Since most of the included studies were of low quality, we did not pool data in a meta-analysis due to heterogeneity (I² > 75%). In WRA, anaemia prevalence ranged from 22.0% to 44.0%; ID from 7.7% and 19.0%; and IDA from 10.5% to 9.7%. The prevalence of anaemia in pregnancy was 29.0% to 42.7%; and 60.6% to 71.3% in HIV-infected pregnant women. Three national surveys reported anaemia in children at 28.9%, 10.7%, and 61.3%, respectively. Overall, among the children under 5 years old, anaemia was more prevalent in 1-year-olds (52.0%) compared to the other age groups. Between 2005 and 2012, ID increased by 3.8% and IDA decreased by 83.2% in children. Anaemia in WRA and children under 5 years in South Africa was a moderate public health concern. Therefore, interventions addressing anaemia should be intensified, and policies on iron supplementation and food fortification need to be revised and aligned to the WHO multiple micronutrient supplementation recommendations.

Assessment of the Nutritional Status of Four Selected Rural Communities in KwaZulu-Natal, South Africa

Under- and over-nutrition co-exist as the double burden of malnutrition that poses a public health concern in countries of the developing regions, including South Africa (SA). Vulnerable groups such as pregnant women and children under five years are the most affected by malnutrition, especially in rural areas. Major contributing factors of malnutrition include food and nutrition insecurity, poverty, and unhealthy lifestyles. The current study aimed to assess the nutritional status, using selected anthropometric indices and dietary intake methods (repeated 24 h recall and food frequency), of four rural communities in KwaZulu-Natal (SA). Purposive sampling generated a sample of 50 households each in three rural areas: Swayimane, Tugela Ferry, and Umbumbulu and 21 households at Fountain Hill Estate. The Estimated Average Requirement cut-point method was used to assess the prevalence of inadequate nutrient intake. Stunting (30.8%; n = 12) and overweight (15.4%; n = 6) were prevalent in children under five years, whilst obesity was highly prevalent among adult females (39.1%; n = 81), especially those aged 16-35 years. There was a high intake of carbohydrates and a low intake of fibre and micronutrients, including vitamin A, thus, confirming the need for a food-based approach to address malnutrition and micronutrient deficiencies, particularly vitamin A deficiency.

Pathology-supported genetic testing as a method for disability prevention in multiple sclerosis (MS). Part II. Insights from two MS cases

In Part I of this Review we evaluated the scientific evidence for a Metabolic Model of multiple sclerosis (MS). Part II outlines the implementation of an adaptive pathology-supported genetic testing (PSGT) algorithm aimed at preventing/reversing disability in two illustrative MS cases, starting with a questionnaire-based risk assessment, including family history and lifestyle factors. Measurement of iron, vitamin B12, vitamin D, cholesterol and homocysteine levels identified biochemical deficits in both cases. Case 1, after following the PSGT program for 15 years, had an expanded disability status scale (EDSS) of 2.0 (no neurological sequelae) together with preserved brain volume on magnetic resonance imaging (MRI). A novel form of iron deficiency was identified in Case 1, as biochemical testing at each hospital submission due to MS symptoms showed low serum iron, ferritin and transferrin saturation, while hematological status and erythrocyte sedimentation rate measurement of systemic inflammation remained normal. Case 2 was unable to walk unaided until her EDSS improved from 6.5 to 4.0 over 12 months after implementation of the PSGT program, with amelioration of her suboptimal biochemical markers and changes to her diet and lifestyle, allowing her to regain independence. Genotype-phenotype correlation using a pathway panel of functional single nucleotide variants (SNVs) to facilitate clinical interpretation of whole exome sequencing (WES), elucidated the underlying metabolic pathways related to the biochemical deficits. A cure for MS will remain an elusive goal if separated from nutritional support required for production and maintenance of myelin, which can only be achieved by a lifelong investment in wellness.

Iron deficiency: a modern primer to diagnosis and management

PURPOSE OF REVIEW

Iron deficiency with anemia (IDA) and without anemia remain a diagnostic and management challenge. Iron deficiency has a broad spectrum of causes, including gastrointestinal malignancy. The purpose of this review is to summarize the value and limitations of current methods to diagnose iron deficiency and underline the relevance of contemporaneous evidence to guide the pretest probability of gastrointestinal disease.

RECENT FINDINGS

A number of biomarkers for iron deficiency exist, and all have their caveats. Serum ferritin remains the most pragmatic means of diagnosing iron deficiency. Hepcidin holds future promise as a marker of iron status during inflammatory states. Men and postmenopausal women with IDA have the highest overall prevalence of gastrointestinal malignancy (∼11%), while premenopausal women with IDA (<1.5%) and those with iron deficiency without anemia (<0.5%) have a very low risk. Noninvasive investigation with fecal immunochemical test and fecal calprotectin hold promise to guide further investigations in lower risk groups.

SUMMARY

Confirmation of iron deficiency remains a challenge. Appropriate risk stratification is the key to guiding judicious gastrointestinal investigation. Use of noninvasive tests may play an important role in lower risk groups. Risk prediction tools applicable to relevant populations are required.

South African Society of Anaesthesiologists Perioperative Patient Blood Management Guidelines 2020

Anaesthesiologists regularly request and administer blood components to their patients, a potentially life-saving intervention. All anaesthesiologists must be familiar with the indications and appropriate use of blood and blood components and their alternatives, but close liaison with haematologists and their local haematology blood sciences laboratory is encouraged. In the last decade, there have been considerable changes in approaches to optimal use of blood components, together with the use of alternative products, with a need to update previous guidelines and adapt them for anaesthesiologists working throughout the hospital system.

Nutritional and Physicochemical Characterization of Strychnos madagascariensis Poir (Black Monkey Orange) Seeds as a Potential Food Source

Strychnos madagascariensis Poir is an underutilized fruit that is considered a valuable food during droughts and famine. The aim of this research was to characterize the nutritional composition and the flour functional properties, for the use as a potential food source. Seed flour was analysed using a standard enzymatic assay for sugars, acid/neutral detergent analysis for fibre, ether extraction for fat and HPLC for strychnine. Results showed that the seeds contained 41% reducing sugars and 53% fibre. The mineral composition, determined using microwave-assisted acid digestion and inductively coupled plasma optical emission spectrometry (ICP-OES), showed that the seeds contained high quantities of iron (15.78 mg/100 g) and manganese (9.86 mg/100 g). The flour water absorption index (1.37 g/g) was substantially higher than that of wheat, brown rice and tapioca flours and the oil absorption index showed similarities to the reference flours (1.09 g/g). The flour peak (37,788 RVU) and final viscosities (62,928 RVU) were significantly (p < 0.001) higher than the reference flours. This study was the first to quantify the strychnine content (0.08%) in the seeds. Results suggest that the seeds have good potential for food product development; however, further processing is essential to ensure safety for consumption.

Nutritional value, antioxidant and antidiabetic properties of nettles (Laportea alatipes and Obetia tenax)

Nettles are commonly consumed in South Africa, Europe and Asia and are used in traditional medicine to treat a variety of ailments. In this study, the nutritional value of the leaves of nettles (Laportea alatipes and Obetia tenax) was evaluated and compared, when cooked and uncooked. The results showed a decrease in the concentrations of crude protein, vitamin A, vitamin E and metals after cooking of nettles. Although cooking reduced the concentrations of essential elements in nettles, their contribution to the diet remained adequate. L. alatipes presented with reduced levels of Cd (from 1.86 to 0.810 mg kg^-1) and Pb (from 2.87 to 1.88 mg kg^-1) after cooking. Similarly, Cd (from 2.97 to 0.780 mg kg^-1) and Pb (from 2.21 to 0.795 mg kg^-1) levels in O. tenax decreased after cooking, demonstrating the significance of cooking. The antioxidant activity of the nettles was determined using the 2,2-diphenyl-l-picrylhydrazyl (DPPH) free radical and ferric reducing antioxidant power (FRAP) assays. The methanol extract of Obetia tenax showed high ferric reducing power whilst the radical scavenging activity was due to the presence of the bioactive molecule, β-carotene, in the plants which exhibited higher DPPH radical scavenging ability relative to test samples and standards. The in vitro antidiabetic activity of the extracts and compounds from the nettles was better than or comparable to that of the known standard, acarbose, which underscores the prospective antidiabetic properties of nettles. Overall, our study provides scientific validation for the ethno-medicinal use of nettles and supports their consumption, which highlights their potential as nutraceuticals.

Prevalence of Iron Deficiency (ID) without anemia in the general population presenting to primary care clinics: a cross-sectional study

OBJECTIVES

There are no evidence-based recommendations to screen for iron deficiency in non-anemic patients, even though symptoms may be present. The aim of this study is to measure the prevalence of iron deficiency (ID) without anemia in the general population aged 18-50 presenting to primary care along with the incidence and time to develop anemia in the iron-deficient population.

METHODS

A single-center retrospective chart review of patients who presented to family medicine clinics between June 2010 and March 2018 at the American University of Beirut Medical Center (AUBMC). Adults 18-50 years old, who had a CBC and ferritin levels ordered with the proximity of maximum four weeks, with an absence of current or previously documented anemia (back to 2007) defined as MCV less than 80 or hemoglobin (Hb) less than 12 in females and 13 in males were included. ID was defined as serum ferritin level below 30 ng/mL.

RESULTS

A total of 1,784 adults aged 18-50 years were included. The prevalence of iron deficiency without anemia was 57.5% [95% confidence interval, 55.08% to 59.92%] among females and 7.6% [95% confidence interval, 3.77% to 11.43%] among males. Iron deficiency without anemia was significantly associated with the level of hemoglobin (Hb) among females (Chi-square, p < 0.001). Overt iron deficiency anemia developed within the 5 years follow up in 14% of females and 0.5% of males. There was a statistically significant association between iron deficiency and menorrhagia (Chi-square, P-value = 0.004), dizziness (Chi-square, P-value = 0.018), dyspnea/shortness of breath (Chi-square, P-value = 0.020), polycystic ovarian syndrome (Chi-square, P-value = 0.0256) and rheumatoid arthritis (Chi-square, P-value = 0.00278).

CONCLUSION

Iron deficiency without anemia in childbearing females is common but only one-seventh of females developed anemia within 5 years. Guidelines should consider incorporating ferritin levels with CBC in the workup of patients presenting with symptoms suggestive of iron deficiency or anemia.

The relationship between measurement of in vivo brain glutamate and markers of iron metabolism: A proton magnetic resonance spectroscopy study in healthy adults

Fundamental human studies which address associations between glutamate and iron metabolism are needed. Basic research reports associations between glutamate and iron metabolism. Human studies report sex differences in iron metabolism and glutamate concentrations, which suggest that these relationships may differ by sex. We hypothesised associations would be apparent between in vivo glutamate and peripheral markers of iron metabolism, and these associations would differ by sex. To test this, we recruited 40 healthy adults (20 men, 20 women) and measured (a) standard clinical biomarker concentrations for iron metabolism and (b) an in vivo proxy for glutamate concentration, glutamate with glutamine in relation to total creatine containing metabolites using proton magnetic resonance spectroscopy studies with a two-dimensional chemical shift imaging slice, with voxels located in bilateral dorsolateral prefrontal cortices, anterior cingulate cortices and frontal white matter. Only the female group reported significant associations between peripheral markers of iron metabolism and Glx:tCr concentration: (a) right dorsolateral prefrontal cortex Glx:tCr associated positively with serum transferrin (r = .60, p = .006) and negatively with transferrin saturation (r = -.62, p = .004) and (b) right frontal white matter Glx:tCr associated negatively with iron concentration (r = -.59, p = .008) and transferrin saturation (r = -.65, p = .002). Our results support associations between iron metabolism and our proxy for in vivo glutamate concentration (Glx:tCr). These associations were limited to women, suggesting a stronger regulatory control between iron and glutamate metabolism. These associations support additional fundamental research into the molecular mechanisms of this regulatory control.

Maternal iron-deficiency is associated with premature birth and higher birth weight despite routine antenatal iron supplementation in an urban South African setting: The NuPED prospective study

Background

Recent studies are suggesting a U-shaped relationship between antenatal iron exposure and birth outcomes. Little is known about the iron status and associated birth outcomes of pregnant women in South Africa. Our aim was to assess iron status at early, mid- and late pregnancy, and to determine associations with gestational age and birth weight in women in Johannesburg, South Africa.

Methods

In this prospective study of 250 pregnant women, we measured haemoglobin, biomarkers of iron status and inflammation at <18, 22 and 36 weeks of gestation, plus birth weight and gestational age at delivery. Associations of anaemia and iron status with birth outcomes were determined using regression models adjusted for confounders.

Results

At enrolment, the prevalence of anaemia, iron depletion (ID) and iron deficiency erythropoiesis (IDE) was 29%, 15% and 15%, respectively, and increased significantly with pregnancy progression. Anaemia and ID at 22 weeks, as well as IDE at 36 weeks were associated with higher birth weight (β = 135.4; 95% CI: 4.8, 266.1 and β = 205.4; 95% CI: 45.6, 365.1 and β = 178.0; 95% CI: 47.3, 308.7, respectively). Women in the lowest ferritin quartile at 22 weeks gave birth to babies weighing 312 g (95% CI: 94.8, 528.8) more than those in the highest quartile. In contrast, IDE at 22 weeks was associated with a higher risk for premature birth (OR: 3.57, 95% CI: 1.24, 10.34) and women in lower haemoglobin quartiles at <18 weeks had a shorter gestation by 7 days (β = -6.9, 95% CI: -13.3, -0.6) compared to those in the highest quartile.

Conclusion

Anaemia, ID and IDE prevalence increased during pregnancy despite routine iron supplementation. ID and anaemia at mid-pregnancy were associated with higher birth weight, while IDE was associated with premature birth. These results suggest that current antenatal screening and supplementation practices in South Africa need to be revisited.

Reference interval determination for glycated albumin in defined subgroups of a South African population

Background

Glycated proteins, such as glycated haemoglobin (HbA1c) and glycated albumin (GA%), are increasingly being used for glycaemic control assessment and the diagnosis of diabetes mellitus. GA% is an intermediate marker of glycaemic control that is not influenced by factors that affect HbA1c concentrations. The aim of this study was to determine reference intervals and assess confounding factors for glycated albumin in a well-characterized healthy population in South Africa.

Methods

We measured glycated albumin using an enzymatic method on stored serum samples of healthy individuals recruited in Cape Town, South Africa. Reference intervals (overall and specific for age, sex and ethnicity) were determined using non-parametric methods and confounding factors were assessed using multiple regression analysis.

Results

The reference interval (2.5th to 97.5th percentile) for glycated albumin of 663 healthy individuals (mean age, 34 years, 38.6% males) ranged from 10.7 to 15.2%. Sex, body mass index categories and ethnicity were significantly associated with the glycated albumin and were considered of practical importance because their standardized regression coefficients (Beta) were greater than a cut-off of 0.15, implying a stronger effect on glycated albumin ( P < 0.001). The glycated albumin reference intervals for subjects with body mass index <25 kg/m2 was 11.2–15.3%, for body mass index 25–30 kg/m2 it was 10.5–14.9% and 10.0–14.6% for body mass index >30 kg/m2 ( P = 0.0001).

Conclusions

The overall reference interval showed good correlation with reference intervals determined in other studies. However, sex, ethnicity and body mass index were statistically significant confounding factors that may influence the overall reference interval. Therefore, overall glycated albumin reference intervals should be used cautiously.

Prevalence of anemia among adults at Hawassa University referral hospital, Southern Ethiopia

INTRODUCTION

Anemia is a public health problem in Ethiopia. In spite of the fact that anemia is a common health burden with much severe consequences, the prevalence of the different types of anemia and its severity have not yet been well documented in different parts of the country. The study aimed to assess the prevalence of different types of anemia, including severity and association with age and sex of study population.

MATERIALS AND METHODS

Four hundred anemic patients who are men and non-pregnant women above 15 years of age were selected from patients visiting the laboratory for Complete Blood Count (CBC) investigation. The type and severity of anemia were assessed based on red cell indices and haemoglobin levels respectively. Data was analyzed using SPSS version 19. Chi square was used at 95% confidence interval, considering P < 0.05 statistically significant for association among categorical variables.

RESULT

The overall prevalence of anemia in the study was 13%. Majority of cases had mild anemia 58.5%, while 19.0%, and 22.5% of the patients had moderate and severe anemia respectively. Overall, the prevalence of mild anemia increases with age, while the prevalence of moderate and severe anemia decreases as age increases. In the present study, the most common anemia was normocytic, which mostly occur in the elderly (61-85) years of age.

CONCLUSION

The CBC parameters help to diagnose and classify anemia in to major components, which might help for a better treatment practice in developing countries, where additional investigations are not available for a reliable diagnosis and classification of anemia. Despite resource limitations in developing countries, additional anaemia work up such as iron studies and markers of inflammation, will provide a more efficient diagnosis of anaemia.

Performance of glycated albumin for type 2 diabetes and prediabetes diagnosis in a South African population

OBJECTIVE

To assess the utility of glycated albumin (GA%) as a diagnostic marker of type 2 diabetes and prediabetes in an African population.

METHODS

GA% levels were determined in a sample of 1294 mixed ancestry adults (74.2% women) residing in Cape Town using an enzymatic method. The participants' glycemic status was based on oral glucose tolerance test (OGTT).

RESULTS

The mean age was 47.8 years with a mean body mass index (BMI) of 28.7 kg/m². Obesity was more pronounced in the screen-detected diabetes and prediabetes groups with mean BMI's of 32.5 kg/m² and 31.5 kg/m² respectively. The optimal thresholds of GA% to diagnose screen-detected diabetes and prediabetes, were 14.90% and 12.75% respectively. For screen-detected diabetes, the C-statistic was higher for HbA1c than GA% (p = .034) with values of 0.899 (95% CI 0.855-0.943) and 0.873 (0.782-0.892) respectively. The agreement between GA% and HbA1c at their optimal thresholds for diagnosing screen-detected diabetes, was kappa = 0.33 (95% CI 0.26-0.40) and was higher than the agreement for prediabetes, kappa = 0.16 (0.11-0.21). The performance of GA% to identify screen-detected diabetes at the optimal threshold of 14.90%, was 64.8% (95% CI 54.1%-74.6%) for sensitivity and 93.5% (92.0%-94.9%) for specificity. GA% was significantly less sensitive, but more specific than HbA1c (at the optimal threshold of 6.15%) for screen-detected diabetes diagnosis (both p ≤ .002 from McNemar tests for sensitivity and specificity comparisons).

CONCLUSIONS

GA% performed less well than HbA1c to identify participants with OGTT-diagnosed type 2 diabetes or prediabetes (HbA1c cut-off of 6.15% and 5.95% respectively) in this population.

The iron status of South African blood donors: balancing donor safety and blood demand

BACKGROUND

Several studies in developed countries have demonstrated high levels of iron deficiency (ID) among blood donors. There is a paucity of data for developing countries where blood shortages remain a major concern.

STUDY DESIGN AND METHODS

A total of 4412 donors were enrolled in the study. Specimens were collected for full blood count, iron, transferrin saturation, and ferritin assessment. Donor demographics were recorded. ID was indicated by a ferritin level of less than 20 ng/mL for men and less than 12 ng/mL for women. Anemia was defined as hemoglobin levels less than 12.5 g/dL. Regression models for predictors of ID were developed.

RESULTS

A total of 17.5% of all donors had ID, with 16.3% prevalence in women and 18.6% in men. Low hemoglobin had the highest association with ID (adjusted odds ratio [AOR], 11.078; 95% confidence interval [CI], 7.915-15.505); male donors had twice the odds of ID compared to female donors (AOR, 2.501; 95% CI, 1.964-3.185), while increasing age was associated with lower odds (AOD, 0.965; 95% CI, 0.956-0.975). Among male donors, an interdonation interval of less than 3 months (AOR, 2.679; 95% CI, 1.929-3.720) was associated with ID. Compared to other females combined, colored female donors (AOR, 2.335; 95% CI, 1.310-4.160) had higher odds and black female donors (AOR, 0.559; 95% CI, 0.369-0.845) lower odds of ID.

CONCLUSION

ID is common among South African donors; low hemoglobin, gender, ethnicity, and past donation history is independently associated with ID. Recommendations aimed at protecting donor health may increase blood shortages in South Africa.

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.

Iron loading, alcohol and mortality: A prospective study

BACKGROUND & AIMS

The relationship between total body iron and cardiovascular disease remains controversial and information absent in black sub-Saharan Africans in whom alcohol consumption tends to be high. The level of total body iron is tightly regulated, however this regulation is compromised by high alcohol intake causing iron loading. The aim of this study is to investigate total body iron, as represented by serum ferritin, and its interaction with measures of alcohol intake in predicting all-cause and cardiovascular mortality.

METHODS

We followed health outcomes for a median of 9.22 years in 877 randomly selected HIV negative African women (mean age: 50.4 years).

RESULTS

One hundred and five deaths occurred of which 40 were cardiovascular related. Ferritin averaged 84.0 (5th to 95th percentile interval, 7.5-533.3) ng/ml and due to the augmenting effect of inflammation, lowered to 75.3 (6.9-523.2) ng/ml after excluding 271 participants with high-sensitivity C-reactive protein (CRP) levels (above 8 mg/l). CRP increased by quartiles of ferritin in the total group (P trend = 0.002), but this relationship was absent after excluding the 271 participants with high CRP values (P trend = 0.10). Ferritin, gamma-glutamyl transferase and carbohydrate deficient transferrin (all P < 0.0001) were higher in drinkers compared to non-drinkers, but CRP was similar (P = 0.77). In multivariable-adjusted analyses, ferritin predicted both all-cause (hazard ratio, 2.08; 95% confidence interval, 1.62-2.68; P < 0.0001) and cardiovascular (1.94; 1.29-2.92; P = 0.002) mortality. In participants with CRP levels below or equal to 8 mg/l, the significant relationship remained between ferritin and all-cause (2.51; 1.81-3.49; P < 0.0001) and cardiovascular mortality (2.34; 1.45-3.76; P = 0.0005). In fully adjusted models, interactions existed between ferritin and gamma-glutamyl transferase, self-reported alcohol use and carbohydrate deficient transferrin in predicting all-cause (P ≤ 0.012) and cardiovascular mortality (P ≤ 0.003).

CONCLUSIONS

Iron loading in African women predicted all-cause and cardiovascular mortality and the intake of alcohol seems mechanistically implicated.

Cross-sectional relationship between haemoglobin concentration and measures of physical and cognitive function in an older rural South African population

Background

Age cohort differences in haemoglobin concentrations and associations with physical and cognitive performance among populations of lower income and middle-income countries have not previously been described. We examined the association between these factors among older men and women in rural South Africa.

Methods

We analysed cross-sectional data from a population-based study of rural South African men and women aged 40 and over (n=4499), with data drawn from questionnaire responses, a cognitive battery, objective physical function tests and blood tests. Anaemia was defined as a haemoglobin concentration <12 g/dL for women and <13 g/dL for men. We related haemoglobin concentrations to each of age, grip strength, walk speed and a latent cognitive function z-score for men and women separately. We used unadjusted correlations and linear models to adjust for comorbidities and inflammation.

Results

In total, 1042 (43.0%) women and 833 (40.1%) men were anaemic. Haemoglobin concentrations were inversely correlated with age for men but not for women; in adjusted analyses, haemoglobin was 0.3 g/dL lower per decade older for men (95% CI 0.2 to 0.4 g/dL). In adjusted analyses, haemoglobin concentration was independently associated with grip strength in women (B=0.391, 95% CI 0.177 to 0.605), but this did not reach significance in men (B=0.266, 95% CI −0.019 to 0.552); no associations were observed between haemoglobin levels and walk speed or cognitive score.

Conclusions

Anaemia was prevalent in this study population of middle-aged and older, rural South African adults, but in contrast to high-income countries, it was not associated with poor physical or cognitive function. Our findings need to be replicated in other populations.

Fractional anisotropy of white matter, disability and blood iron parameters in multiple sclerosis

Multiple sclerosis (MS) is a disorder related to myelin damage, which can be investigated by neuroimaging techniques such as fractional anisotropy (FA), a measure of microstructural white matter properties. The objectives of this study were to investigate (1) the relationship between FA and disability using an extremes of outcome approach, and (2) whether blood iron parameters were associated with FA and/or disability. Patients diagnosed with MS (n = 107; 14 males and 93 females) had iron parameter tests and disability determinations using the Expanded Disability Status Scale (EDSS). FA was recorded in 48 white matter tracts in 11 of the female patients with MS and 12 female controls.

RESULTS

In patients with high disability scores the mean FA was significantly lower (0.34 ± 0.067) than in the control group (0.45 ± 0.036; p = 0.04), while patients with low disability had mean FA values (0.44 ± 0.014) similar to controls (p = 0.5). Positive associations were found between FA and the iron parameters serum iron, ferritin and percentage transferrin saturation (%Tfsat) in all the white matter tracts. For % Tfsat, the associations were highly significant in 14 tracts (p < 0.01; r-values 0.74-0.84) and p < 0.001 (r = 0.83) in the superior fronto occipital fasciculus (LH). In the whole patient group a trend was found towards an inverse association between the EDSS and the %Tfsat (r = -0.26, p = 0.05) after excluding male gender and smoking as confounders, suggesting reduced disability in the presence of higher blood iron parameters. Additionally, significant inverse associations between disease duration and haemoglobin (p = 0.04) as well as %Tfsat (p = 0.02) suggested that patients with MS may experience a decrease in blood iron concentrations over time.

Understanding the determinants of hemoglobin and iron status: adolescent-adult women comparisons in SANHANES-1

The study compared hemoglobin (Hb) and serum ferritin levels between adolescent and adult women with different body mass indices, dietary intake, and sociodemography. A secondary analysis of data for 3177 South African women ⩾15 years of age who participated in the SANHANES-1 study was undertaken. Abnormal Hb (≤12 g/dL) and serum ferritin (<15 μg/mL) were based on the World Health Organization's criteria for nonpregnant women aged ⩾15 years. Data were analyzed using STATA version 11. Overall, anemia was detected in 740 (23.3%) participants. Of the individuals in the subsample (n = 1123, 15-35 years) who had serum ferritin measured, 6.0% presented with iron depletion (ID) and 10.8% presented with iron-deficiency anemia (IDA). The highest prevalences of anemia, ID, and IDA were in 15- to 18-year-olds (11.2%, 8.8%, and 20.2%, respectively). Black young adults (19-24 years) were up to 40 times more likely to present with ID compared with their non-black counterparts. While overweight adolescents were three times more likely to be anemic, overweight and obese young adults, as well as obese older adults (25-35 years), were less likely to be anemic compared with normal-weight women of all age groups. Overconsumption of dietary fat increased ID by up to 54- and 11-fold (adolescents and 25- to 35-year-olds, respectively). In South Africa, anemia is most prevalent in adolescents and black women. Anemia is also an indicator of overconsumption of dietary fat and a marker of socioeconomic disadvantage.

Evaluation of a competitive hepcidin ELISA assay in the differential diagnosis of iron deficiency anaemia with concurrent inflammation and anaemia of inflammation in elderly patients

In this study, a competitive hepcidin ELISA assay was evaluated for its ability to differentiate between iron deficiency anaemia with concurrent inflammation and anaemia of inflammation in elderly patients, using the absence of stainable bone marrow iron as the diagnostic criterion for iron deficiency. In addition, correlation coefficients for hepcidin versus C-reactive protein, ferritin and interleukin-6 were determined. The optimal cut-off for hepcidin was 21 μg/L, corresponding to sensitivity and specificity of 100% and 67%, respectively, for iron deficiency. For ferritin, a sensitivity and specificity of 91% and 83%, respectively, correspond to an optimal cut-off of 87 μg/L. Receiver operating characteristics curve analysis revealed that ELISA analysis of hepcidin is not superior to ferritin in the diagnosis of iron deficiency in elderly anaemic patients with concurrent inflammation. Hepcidin shows a strong positive correlation with ferritin, and also correlates positively with C-reactive protein in this patient population.