Prevalence of Iron Deficiency and Iron-Deficiency Anemia in US Females Aged 12-21 Years, 2003-2020

Factors moderating cadmium bioavailability: Key considerations for comparing blood cadmium levels between groups

Cadmium (Cd) is recognized as a significant hazard to human health, with exposure linked to a variety of adverse outcomes including various cancers, cardiovascular diseases, chronic kidney disease, and osteoporosis. Residing in areas contaminated with Cd is undoubtedly a risk factor for developing the aforementioned conditions. However, the risk of developing Cd-related disorders is not uniform among individuals. Deficiencies in iron, zinc, and calcium, along with iron deficiency anemia, decreased lung function often seen in chronic obstructive pulmonary disease (COPD), and low circulating levels of parathyroid hormone (PTH), may enhance Cd intestinal absorption. Conversely, chronic liver disorders can lead to the progressive loss of hepatocytes and the release of free Cd into the circulation, resulting in elevated Cd blood levels. Moreover, studies comparing Cd blood levels between different regions within a country or between two groups of individuals, for example, those with and without osteoporosis, should consider all variables that may impact Cd levels. These include age, sex, alcohol consumption, blood levels of iron, calcium, and zinc, the presence of anemia, COPD, PTH levels, and the presence of liver or kidney disease. In this review, we delve into all factors that could influence Cd blood levels, providing a comprehensive analysis.

High prevalence of iron deficiency and socioeconomic disparities in laboratory screening of non-pregnant females of reproductive age: A retrospective cohort study

Iron deficiency anemia (IDA) and non-anemic iron deficiency (NAID) are highly prevalent among non-pregnant females of reproductive age. Canada has no national screening guidelines for this population. Screening, when performed, is often with a complete blood count alone without ferritin or iron indices. The primary objective was to determine the prevalence of screening for NAID and IDA over a 3-year period in non-pregnant females of reproductive age who had tests performed at outpatient laboratories in Ontario, Canada. Retrospective cohort study of non-pregnant females ages 15-54 in Ontario, from 2017 to 2019. NAID was defined as ferritin <30 μg/L, anemia as hemoglobin <120 g/L, and IDA as ferritin <30 μg/L and hemoglobin <120 g/L. Annual household income was estimated using patient postal codes. A total of 784 132 non-pregnant females were included. The 82.1% were screened for iron deficiency, 38.3% had NAID and 13.1% had IDA; 55.6% with IDA had normal mean corpuscular volumes. The median household income was $89454.80 compared with a provincial median of $65285.00. Patients in the lowest income quintile had the highest odds of being anemic, and the lowest odds of having a ferritin checked. A large proportion of non-pregnant females of reproductive age in this cohort were screened for iron deficiency. In this relatively privileged cohort, NAID affected nearly 40%, and IDA 13%. Most patients with IDA did not have microcytosis. Low household income was associated with the greatest odds of anemia and the lowest odds of being screened, highlighting inequitable access to screening for IDA in Ontario, Canada.

AGA Clinical Practice Update on Management of Iron Deficiency Anemia: Expert Review

DESCRIPTION

In this Clinical Practice Update (CPU), we will Best Practice Advice (BPA) guidance on the appropriate management of iron deficiency anemia.

METHODS

This expert review was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the CPUC and external peer review through standard procedures of Clinical Gastroenterology and Hepatology. These Best Practice Advice (BPA) statements were drawn from a review of the published literature and from expert opinion. Since systematic reviews were not performed, these BPA statements do not carry formal ratings regarding the quality of evidence or strength of the presented considerations. BEST PRACTICE ADVICE 1: No single formulation of oral iron has any advantages over any other. Ferrous sulfate is preferred as the least expensive iron formulation. BEST PRACTICE ADVICE 2: Give oral iron once a day at most. Every-other-day iron dosing may be better tolerated for some patients with similar or equal rates of iron absorption as daily dosing. BEST PRACTICE ADVICE 3: Add vitamin C to oral iron supplementation to improve absorption. BEST PRACTICE ADVICE 4: Intravenous iron should be used if the patient does not tolerate oral iron, ferritin levels do not improve with a trial of oral iron, or the patient has a condition in which oral iron is not likely to be absorbed. BEST PRACTICE ADVICE 5: Intravenous iron formulations that can replace iron deficits with 1 or 2 infusions are preferred over those that require more than 2 infusions. BEST PRACTICE ADVICE 6: All intravenous iron formulations have similar risks; true anaphylaxis is very rare. The vast majority of reactions to intravenous iron are complement activation-related pseudo-allergy (infusion reactions) and should be treated as such. BEST PRACTICE ADVICE 7: Intravenous iron therapy should be used in individuals who have undergone bariatric procedures, particularly those that are likely to disrupt normal duodenal iron absorption, and have iron-deficiency anemia with no identifiable source of chronic gastrointestinal blood loss. BEST PRACTICE ADVICE 8: In individuals with inflammatory bowel disease and iron-deficiency anemia, clinicians first should determine whether iron-deficiency anemia is owing to inadequate intake or absorption, or loss of iron, typically from gastrointestinal bleeding. Active inflammation should be treated effectively to enhance iron absorption or reduce iron depletion. BEST PRACTICE ADVICE 9: Intravenous iron therapy should be given in individuals with inflammatory bowel disease, iron-deficiency anemia, and active inflammation with compromised absorption. BEST PRACTICE ADVICE 10: In individuals with portal hypertensive gastropathy and iron-deficiency anemia, oral iron supplements initially should be used to replenish iron stores. Intravenous iron therapy should be used in patients with ongoing bleeding who do not respond to oral iron therapy. BEST PRACTICE ADVICE 11: In individuals with portal hypertensive gastropathy and iron-deficiency anemia without another identified source of chronic blood loss, treatment of portal hypertension with nonselective β-blockers can be considered. BEST PRACTICE ADVICE 12: In individuals with iron-deficiency anemia secondary to gastric antral vascular ectasia who have an inadequate response to iron replacement, consider endoscopic therapy with endoscopic band ligation or thermal methods such as argon plasma coagulation. BEST PRACTICE ADVICE 13: In patients with iron-deficiency anemia and celiac disease, ensure adherence to a gluten-free diet to improve iron absorption. Consider oral iron supplementation based on the severity of iron deficiency and patient tolerance, followed by intravenous iron therapy if iron stores do not improve. BEST PRACTICE ADVICE 14: Deep enteroscopy performed in patients with iron-deficiency anemia suspected to have small-bowel bleeding angioectasias should be performed with a distal attachment to improve detection and facilitate treatment. Small-bowel angioectasias may be treated with ablative thermal therapies such as argon plasma coagulation or with mechanical methods such as hemostatic clips. BEST PRACTICE ADVICE 15: Endoscopic treatment of angioectasias should be accompanied with iron replacement. Medical therapy for small-bowel angioectasias should be reserved for compassionate treatment in refractory cases when iron replacement and endoscopic therapy are ineffective.

Re-evaluating treatment thresholds in patient blood management: Female patients experience more perioperative anaemia and higher transfusion rates in major elective surgery

BACKGROUND AND OBJECTIVES

By optimizing erythropoiesis, patient blood management (PBM) programmes can reduce transfusions, lower mortality and provide cost-effective care. While definitions of anaemia have historically varied by sex, for the purposes of PBM, anaemia is defined as a haemoglobin <130 g/L. Our objective was to describe whether perioperative anaemia and transfusion rates in the PBM setting vary by sex.

MATERIALS AND METHODS

We conducted a retrospective study of the Ontario Nurse Transfusion Coordinators Program (ONTraC) database from 2018 to 2022. ONTraC collects data from 25 Ontario hospitals which together account for >70% of Ontario's provincial blood use (~400,000 units per year). We collected data on patients undergoing elective isolated coronary artery bypass graft surgery (CABG), open heart valve replacement, CABG plus valve replacement, single-knee arthroplasty and single-hip arthroplasty.

RESULTS

From 2018 to 2022, 17,700 patients were included in the ONTraC program; 47% were females (N = 8376). Across almost all years and procedures, females were found to have a significantly lower pre-operative, nadir and discharge haemoglobin as compared with males, irrespective of PBM interventions. Transfusion rates were significantly higher for females; this was most pronounced in cardiac surgery.

CONCLUSION

Females experienced more perioperative anaemia and higher transfusion rates. Historic sex-specific definitions of anaemia may contribute to a greater tolerance of anaemia in females. Prioritizing females for multimodal PBM and consistently achieving a pre-operative haemoglobin >130 g/L may reduce the amount of red blood cell (RBC) transfusions that female patients receive.

The origin of ferritin reference intervals: a systematic review

Iron deficiency is a highly prevalent condition, which contributes to unnecessary morbidity, mortality, and health inequity. A serum ferritin concentration of less than 30 μg/L has a high specificity and sensitivity for diagnosing iron deficiency in adults, but the laboratory reported lower limit of normal (LLN) is typically lower. These LLNs might not be rooted in rigorous scientific evidence and might be contributing to structural underdiagnosis of iron deficiency. A systematic review was done per systematic reviews and meta-analysis guidelines with the use of medical literature databases from inception of each database to Nov 30, 2021, to identify studies that determined ferritin reference intervals in healthy adults and grey literature search for the five most common ferritin assays (registration number CRD42022268844). The objectives were to systematically summarise the ferritin reference intervals and to do a methodological quality assessment of the included studies. 2306 studies were screened and 61 full texts were included. 37 studies were eligible for analysis of the ferritin LLN in the general population. The population the sample was comprised of was a total of 21 882 females and 23 650 males participants. The ferritin LLN was a median of 8 μg/L (IQR 5-15) and mean of 9 μg/L (SD 11) in females and a median of 25 μg/L (IQR 16-44) and mean of 25 μg/L (SD 29) in males. 30 (49%) of 61 studies did not explicitly screen for patients at risk of iron deficiency, and 32 (52%) did not refer to a reference interval establishment guideline (eg, guideline recommended by Clinical and Laboratory Standards Institute). The five most used commercial ferritin laboratory assays reported reference intervals with a median LLN of 11 (IQR 9-12) and mean of 9 μg/L (SD 4) for females and median of 22 (IQR 22-24) and mean of 23 μg/L (SD 4) for males. In the literature, serum ferritin reference intervals in healthy adults consistently report a LLN of less than 30 μg/L. Data driving these ferritin reference intervals are at high risk of bias, given no exclusion of individuals at risk for iron deficiency in the presumed normal population sample and no adherence to reference interval establishment standards. We suggest the use of evidence-based laboratory clinical decision limits to diagnose iron deficiency.

Prevalence of Iron Deficiency Using 3 Definitions Among Women in the US and Canada

Importance

The prevalence of iron deficiency varies widely according to how it is defined.

Objective

To compare the prevalence of iron deficiency among women using 3 different definitions.

Design, Setting, and Participants

The cross-sectional Hemochromatosis and Iron Overload Screening Study (HEIRS; 2000-2006) evaluated the prevalence, determinants, and outcomes of hemochromatosis and other iron-related disorders. Multiethnic, primary care-based screening (2001-2003) was performed at 5 field centers (4 in the US and 1 in Canada). Volunteer women aged 25 years and older were recruited at primary care venues associated with the field centers. Data were analyzed from June to December 2023.

Main Outcomes and Measures

Measures included transferrin saturation, serum ferritin level, and self-reported age, pregnancy, and race and ethnicity. Three iron deficiency definitions were studied: (1) combined transferrin saturation less than 10% and serum ferritin less than 15 ng/mL (HEIRS), (2) serum ferritin less than 15 ng/mL (World Health Organization [WHO]), and (3) serum ferritin less than 25 ng/mL (a threshold for iron-deficient erythropoiesis [IDE]).

Results

Among 62 685 women (mean [SD] age, 49.58 [14.27] years), 1957 women (3.12%) had iron deficiency according to the HEIRS definition, 4659 women (7.43%) had iron deficiency according to the WHO definition, and 9611 women (15.33%) had iron deficiency according to the IDE definition. Among 40 381 women aged 25 to 54 years, 1801 women (4.46%) had iron deficiency according to HEIRS, 4267 women (10.57%) had iron deficiency according to WHO, and 8573 women (21.23%) had iron deficiency according to IDE. Prevalence rates of iron deficiency among 2039 women aged 25 to 44 years who reported pregnancy were 5.44% (111 women) according to HEIRS, 18.05% (368 women) according to WHO, and 36.10% (736 women) according to IDE. Iron deficiency prevalence by the 3 respective definitions increased significantly in each racial and ethnic group and was significantly higher among Black and Hispanic participants than Asian and White participants. The relative iron deficiency prevalence among the 62 685 women increased 2.4-fold (95% CI, 2.3-2.5; P < .001) using the WHO definition and increased 4.9-fold (95% CI, 4.7-5.2; P < .001) using the IDE definition.

Conclusions and Relevance

Three definitions of iron deficiency were associated with significantly different prevalence of iron deficiency in women, regardless of self-reported age, pregnancy, or race and ethnicity. Using higher serum ferritin thresholds to define iron deficiency could lead to diagnosis and treatment of more women with iron deficiency and greater reduction of related morbidity.

Risk of abnormal uterine bleeding associated with high-affinity compared with low-affinity serotonin and norepinephrine reuptake inhibitors

BACKGROUND

Concerns have been raised about the potential association between selective serotonin reuptake inhibitors (SSRIs)/serotonin-norepinephrine reuptake inhibitors (SNRIs) and the risk of abnormal uterine bleeding (AUB), which may be influenced by the affinity of SSRIs/SNRIs for serotonin transporter. Thus, we assessed whether SSRIs/SNRIs with high-affinity for serotonin transporter are associated with AUB compared to SSRIs/SNRIs with low-affinity in non-pregnant women.

METHODS

Using the UK Clinical Practice Research Datalink, we identified a cohort of women aged 15-24 years, newly prescribed a high- or low-affinity SSRI/SNRI between 1990 and 2019. Confounding was addressed using standardized morbidity ratio weighting. We used weighted Cox proportional hazards models to estimate the hazard ratio (HR) and 95 % confidence interval (CI) of AUB associated with high-affinity compared with low-affinity SSRIs/SNRIs. We assessed the risk of anemia as a secondary outcome.

RESULTS

The cohort included 156,307 users of high-affinity SSRIs/SNRIs and 102,631 users of low-affinity SSRIs/SNRIs. High-affinity SSRIs/SNRIs were not associated with an increased risk of AUB compared with low-affinity SSRIs/SNRIs (incidence rates: 46.3 versus 42.4 per 1000 person-years, respectively; HR 1.01, 95 % CI 0.93-1.09). Duration of use, age, and comorbidities did not modify the risk. However, high-affinity SSRIs/SNRIs were associated with an increased risk of anemia (HR 1.29, 95 % CI 1.04-1.61) compared with low-affinity SSRIs/SNRIs.

LIMITATIONS

Residual confounding may still be present.

CONCLUSIONS

The risk of AUB did not differ between high- and low-affinity SSRIs/SNRIs. However, the potential risk of anemia suggests the need for monitoring and further investigation of the risk of AUB with these medications.

Association between CFTR modulators and changes in iron deficiency markers in cystic fibrosis

BACKGROUND

Iron deficiency (ID) is a common extrapulmonary manifestation in cystic fibrosis (CF). CF transmembrane conductance regulator (CFTR) modulator therapies, particularly highly-effective modulator therapy (HEMT), have drastically improved health status in a majority of people with CF. We hypothesize that CFTR modulator use is associated with improved markers of ID.

METHODS

In a multicenter retrospective cohort study across 4 United States CF centers 2012-2022, the association between modulator therapies and ID laboratory outcomes was estimated using multivariable linear mixed effects models overall and by key subgroups. Summary statistics describe the prevalence and trends of ID, defined a priori as transferrin saturation (TSAT) <20 % or serum iron <60 μg/dL (<10.7 μmol/L).

RESULTS

A total of 568 patients with 2571 person-years of follow-up were included in analyses. Compared to off modulator therapy, HEMT was associated with +8.4 % TSAT (95 % confidence interval [CI], +6.3-10.6 %; p < 0.0001) and +34.4 μg/dL serum iron (95 % CI, +26.7-42.1 μg/dL; p < 0.0001) overall; +5.4 % TSAT (95 % CI, +2.8-8.0 %; p = 0.0001) and +22.1 μg/dL serum iron (95 % CI, +13.5-30.8 μg/dL; p < 0.0001) in females; and +11.4 % TSAT (95 % CI, +7.9-14.8 %; p < 0.0001) and +46.0 μg/dL serum iron (95 % CI, +33.3-58.8 μg/dL; p < 0.0001) in males. Ferritin was not different in those taking modulator therapy relative to off modulator therapy. Hemoglobin was overall higher with use of modulator therapy. The prevalence of ID was high throughout the study period (32.8 % in those treated with HEMT).

CONCLUSIONS

ID remains a prevalent comorbidity in CF, despite availability of HEMT. Modulator use, particularly of HEMT, is associated with improved markers for ID (TSAT, serum iron) and anemia (hemoglobin).

Iron deficiency anemia among women: An issue of health equity

Iron deficiency is the most common and widespread nutritional deficiency in the world. For women, the risk of iron deficiency and iron deficiency anemia increases due to iron demands during pregnancy and regular iron losses due to menstruation during reproductive years. These interrelated conditions are of public health concern as they are highly prevalent, and the negative consequences such as chronic fatigue, cognitive impairment and poor quality of life are broad and multifaceted. People of low socioeconomic status are at higher risk of iron deficiency due to low intake of expensive iron-rich foods, and decreased access to healthcare. In this review, we applied a health equity lens to describe the current state of care for women with iron deficiency with or without anemia. We have highlighted several structural challenges that span from the laboratory diagnosis, inconsistent screening guidelines, and stigma associated with heavy menstrual bleeding, to treatment barriers.

Is It Time to Alter the Standard of Care for Iron Deficiency/Iron Deficiency Anemia in Reproductive-Age Women?

Two billion people worldwide suffer from anemia, with reproductive-age women being disproportionately affected. Iron plays a crucial role in cellular function and impacts cognition, physical function, and quality of life. Iron deficiency (ID) and iron deficiency anemia (IDA) are associated with adverse effects on pregnancy and fetal development. Oral iron supplementation has been the standard treatment for decades, often producing sub-optimal outcomes. Many babies are still being born with ID and suffer adverse sequelae due to inadequate iron levels in the mothers. Is it time to consider a broad scale-up of parenteral iron as a new standard of care?