Possible association of a reduction in cardiovascular events with blood donation

Consensus Statement on the definition and classification of metabolic hyperferritinaemia

Hyperferritinaemia is a common laboratory finding that is often associated with metabolic dysfunction and fatty liver. Metabolic hyperferritinaemia reflects alterations in iron metabolism that facilitate iron accumulation in the body and is associated with an increased risk of cardiometabolic and liver diseases. Genetic variants that modulate iron homeostasis and tissue levels of iron are the main determinants of serum levels of ferritin in individuals with metabolic dysfunction, raising the hypothesis that iron accumulation might be implicated in the pathogenesis of insulin resistance and the related organ damage. However, validated criteria for the non-invasive diagnosis of metabolic hyperferritinaemia and the staging of iron overload are still lacking, and there is no clear evidence of a benefit for iron depletion therapy. Here, we provide an overview of the literature on the relationship between hyperferritinaemia and iron accumulation in individuals with metabolic dysfunction, and on the associated clinical outcomes. We propose an updated definition and a provisional staging system for metabolic hyperferritinaemia, which has been agreed on by a multidisciplinary global panel of expert researchers. The goal is to foster studies into the epidemiology, genetics, pathophysiology, clinical relevance and treatment of metabolic hyperferritinaemia, for which we provide suggestions on the main unmet needs, optimal design and clinically relevant outcomes.

Machine learning-based prediction of fainting during blood donations using donor properties and weather data as features

Background and objectives

Fainting is a well-known side effect of blood donation. Such adverse experiences can diminish the return rate for further blood donations. Identifying factors associated with fainting could help prevent adverse incidents during blood donation.

Materials and methods

Data of 85,040 blood donations from whole blood and apheresis donors within four consecutive years were included in this retrospective study. Seven different machine learning models (random forests, artificial neural networks, XGradient Boosting, AdaBoost, logistic regression, K nearest neighbors, and support vector machines) for predicting fainting during blood donation were established. The used features derived from the data obtained from the questionnaire every donor has to fill in before the donation and weather data of the day of the donation.

Results

One thousand seven hundred fifteen fainting reactions were observed in 228 846 blood donations from 88,003 donors over a study period of 48 months. Similar values for all machine learning algorithms investigated for NPV, PPV, AUC, and F1-score were obtained. In general, NPV was above 0.996, whereas PPV was below 0.03. AUC and F1-score were close to 0.9 for all models. Essential features predicting fainting during blood donation were systolic and diastolic blood pressure and ambient temperature, humidity, and barometric pressure.

Conclusion

Machine-learning algorithms can establish prediction models of fainting in blood donors. These new tools can reduce adverse reactions during blood donation and improve donor safety and minimize negative associations relating to blood donation.

Iron overload, oxidative stress and vascular dysfunction: Evidences from clinical studies and animal models

Although iron is a metal involved in many in vital processes due to its redox capacity, body iron overloads lead to tissue damage, including the cardiovascular system. While cardiomyopathy was the focus since the 1960s, the impact on the vasculature was comparatively neglected for about 40 years, when clinical studies correlating iron overload, oxidative stress, endothelial dysfunction, arterial stiffness and atherosclerosis reinforced an "iron hypothesis". Due to controversial results from some epidemiological studies investigating atherosclerotic events and iron levels, well-controlled trials and animal studies provided essential data about the influence of iron, per se, on the vasculature. As a result, the pathophysiology of vascular dysfunction in iron overload have been revisited. This review summarizes the knowledge obtained from epidemiological studies, animal models and "in vitro" cellular systems in recent decades, highlighting a more harmful than innocent role of iron excess for the vascular homeostasis, which supports our proposal to hereafter denominate "iron overload vasculopathy". Additionally, evidence-based therapeutic targets are pointed out to be tested in pre-clinical research that may be useful in cardiovascular protection for patients with iron overload syndromes.

Health Behavior and Lifestyle Trends among Platelet Donors: Results from a Questionnaire-Based Survey in Norway

Background

Blood donors are on average healthier than the general population, a phenomenon known as the “healthy donor effect.” Earlier studies have also pointed to healthier behaviors among whole blood donors than the general population. This study is aimed at assessing the prevalence of four healthy behaviors (sufficient physical activity, avoiding cigarette smoking, low to moderate alcohol use, and maintaining a healthy weight) among platelet donors and to compare the results with those in the general population of similar ages.

Methods

Eighty-six platelet donors were asked to complete a questionnaire designed to assess physical activity, smoking, and alcohol use. Sociodemographic information including gender, age, and education was also collected from all participants. Chi-square statistics and logistic regression were used in statistical analysis.

Results

The mean age of the study donors was 51 years, 56% were female. Most were employed (90%), and 48% hold a bachelor's or higher degree. The prevalence of healthy behaviors differed by education gradients but not by gender and age. About 49% of the donors met the weekly physical activity recommendations, less than 5% were daily smokers, and~26% were classified as more frequent drinkers (≥1 to ≤5 times per week). The corresponding percentages for the general population were, respectively, 33%, 13%, and 35%. The prevalence of overweight and obesity, as assessed by body mass index (BMI), among donors were 50% and 29%, respectively, much higher than the current prevalence of overweight and obesity of 37% and 19%, respectively, among adults in the general population.

Conclusions

The individual health behaviors of the majority of the study population could be characterized by a relatively high level of physical activity, low prevalence of daily smoking, and moderate alcohol drinking. The above-average overweight/obesity prevalence among platelet donors in this cohort is of concern because of the potential serious health consequences and it warrants further reflection.

Voluntary Blood Donation Knowledge, Attitudes, and Practices in Central Ethiopia

Background

Increasing the availability of safe blood is a major challenge in developing countries. Given the scant amount of community-based data in Africa, this study examines the knowledge, attitudes, and practices of blood donation of Ethiopian adults.

Methods

A cross-sectional study was conducted on 421 adult residents of Adama town using face-to-face interviews with translated questionnaires. Knowledge and attitude levels were assessed using a set of questions and those who answered above mean for knowledge and attitude questions were categorized as above-average knowledge level and favorable attitude, respectively. The data were coded and entered into EPI Info™ version 7, transferred to SPSS version 25 for cleaning and analysis. All variables with p<0.25 in the bivariable analysis were examined as candidate variables in the multivariable logistic regression models.

Results

Less than half, 47% (95% CI: 42–52%) of the study participants have above-average knowledge level about blood donation and 48% (95% CI: 43–53%) have favorable attitudes towards blood donation. Only 17% (95% CI: 13–21%) of study participants ever donated blood of which 14.6% of them donated for replacement and less than 2% (1.95%) are voluntary donors. Younger age of 18–25 AOR: 95% CI: 3.40 (1.30, 12.43), having good knowledge AOR: 95% CI: 2.21 (1.26, 3.89) and favorable attitude AOR: 95% CI: 10.25 (4.90, 21.44) were factors independently associated with blood donation practice.

Conclusion

The level of blood donation practiced in the study area is low. Low knowledge and poor attitudes are independent predictors of low inclination to donate, so awareness creation and improving attitudes in blood donation campaigns, particularly among older people is necessary to increase voluntary blood donation.

A Case-Based Review of Iron Overload With an Emphasis on Porphyria Cutanea Tarda, Hepatitis C, C282Y Heterozygosity, and Coronary Artery Disease

Iron overload can impact disease progression and treatment options for patients with comorbid conditions, such as porphyria cutanea tarda, hepatitis C virus, and coronary artery disease.

Cardiovascular risk in 159 934 frequent blood donors while addressing the healthy donor effect

OBJECTIVE

To investigate whether regular blood donation decreases cardiovascular risk.

METHODS

All 159 934 Dutch whole-blood donors with an active donation career of at least 10 years were categorised into sex-specific donation tertiles based on the number of donations during this 10-year qualification period. Cardiovascular endpoints were based on hospital discharge diagnoses and death certificates from Dutch Hospital Data and Statistics Netherlands and occurring after the 10-year qualification period. Cox regression was used to estimate the age-adjusted and starting year-adjusted hazard rate ratio (HRR).

RESULTS

Female high-frequency blood donors had a reduced cardiovascular morbidity (HRR=0.91, 95% CI 0.85 to 0.98) compared with low-frequency blood donors. No effect was observed in men (HRR=1.00, 95% CI 0.95 to 1.05). To rule out a residual healthy donor effect (HDE), additional sensitivity analyses using a 5-year qualification period were conducted. The results supported the absence of a residual HDE.

CONCLUSIONS

This study showed a protective effect of long-term, high-frequency blood donation against cardiovascular disease. This effect was only observed in women and not in men.

Effects of serial phlebotomy on vascular endothelial function: Results of a prospective double-blind randomized study

INTRODUCTION

Blood donation has been proposed as a potential therapy to reduce risk of cardiovascular disease, but the effects of phlebotomy on vascular function in human subjects have not been well characterized.

AIMS

We conducted a prospective randomized double-blind study to determine the effects of serial phlebotomy on vascular endothelial function in the brachial artery. Eighty-four iron-replete, non-anemic subjects were randomly assigned to one of three study treatment groups: (a) four serial phlebotomy procedures each followed by intravenous infusion of placebo normal saline; (b) four serial phlebotomy procedures each followed by intravenous infusion to replete lost iron; and (c) four serial sham phlebotomy procedures each followed by intravenous infusion of placebo normal saline. Assigned phlebotomy procedures were conducted at 56-day intervals. We measured brachial artery reactivity (BAR, %) in response to transient oxidative stress induced by oral methionine with high-resolution duplex ultrasound imaging before and one week after the fourth study phlebotomy.

RESULTS

Before phlebotomy, oral methionine decreased BAR by -2.04% (95% CI -2.58%, -1.50%), P < 0.001) with no significant difference between groups (P = 0.42). After phlebotomy, the BAR response to oral methionine did not significantly change between groups (P = 0.53). Brachial artery nitroglycerin-mediated dilation did not change in response to phlebotomy.

CONCLUSIONS

Four serial phlebotomy procedures over six months with or without intravenous iron supplementation did not alter vascular endothelial function in the brachial artery when compared with sham phlebotomy.

Trace minerals intake: Risks and benefits for cardiovascular health

Minerals play a major role in regulating cardiovascular function. Imbalances in electrolyte minerals are frequent and potentially hazardous occurrences that may lead to the development of cardiovascular diseases (CVDs). Transition metals, such as iron, zinc, copper and selenium, play a major role in cell metabolism. However, there is controversy over the effects of dietary and supplemental intake of these metals on cardiovascular risk factors and events. Since their pro-oxidant or antioxidant functions can have different effects on cardiovascular health. While deficiency of these trace elements can cause cardiovascular dysfunction, several studies have also shown a positive association between metal serum levels and cardiovascular risk factors and events. Thus, a J- or U-shaped relationship between the transition minerals and cardiovascular events has been proposed. Given the existing controversies, large, well-designed, long-term, randomized clinical trials are required to better examine the effects of trace mineral intake on cardiovascular events and all-cause mortality in the general population. In this review, we discuss the role of dietary and/or supplemental iron, copper, zinc, and selenium on cardiovascular health. We will also clarify their clinical applications, benefits, and harms in CVDs prevention.

The impact of multiple blood donations on the risk of cardiovascular diseases: Insight of lipid profile

OBJECTIVES

The reduction in blood viscosity and iron store were proposed to be connected to the reduction in the risk of cardiovascular disease (CVD) among multiple blood donors. Herein, we evaluated the modulation of serum lipids levels in accordance with donation events. Furthermore, atherogenic impacts on the risk of CVD were investigated.

MATERIALS AND METHODS

A total of 100 voluntarily male donors were included in the study. Fifty donors were multiple time donors (MTD) and 50 were single time donors (STD). Levels of serum lipids were determined and atherogenic indices including TG/HDL and CHO/HDL ratios were calculated. QRISK2 parameters were determined to evaluate the 10-years risk of developing CVD.

RESULTS

Among MTD, there were significantly higher serum levels of triglycerides (TG) and very low-density lipoproteins (VLDL) combined with significantly lower HDL level. These modulations were significantly correlated to the extent of donation. Both CHO/HDL and TG/HDL ratios were also significantly higher among MTD. However, only TG/HDL ratio was strongly correlated to the donation extent even when controlled for age, BMI and smoking status. Despite the significant difference in QRISK2 parameters between study groups, none of these parameters was correlated to the extent of donation when controlling for age, BMI and smoking status.

CONCLUSION

We demonstrate that multiple blood donation is associated with an unfavorable modulation of serum levels of lipids that is influenced by donation extent. This modulation is not associated with an increased risk of CVD but may weakly contribute in a higher risk for coronary heart disease (CHD).

Donating blood on a regular basis appears to reduce blood pressure, but appearances can be deceiving

BACKGROUND

Previous studies have reported a relationship between blood donation and decreased risk for cardiovascular events, and it has been proposed that this may be due to a lowering of blood pressure among hypertensive individuals who donate on a regular basis.

STUDY DESIGN AND METHODS

With the use of a retrospective longitudinal analysis, predonation blood pressure readings were examined across consecutive whole blood donations for New York Blood Center donors. With blood pressure levels recorded at the first, second, third, and fourth donations, the sample was divided into three subgroups including high (≥140 mmHg), intermediate (>100 and <40 mmHg), and low (≤100 mmHg) systolic blood pressure (SBP). In addition, a computational approach was used to estimate regression to the mean effects for donors with high SBP or high diastolic blood pressure (DBP) at their first, second, or third donation.

RESULTS

Visual examination of SBP and DBP patterns across donations revealed that, on average, donors with extreme values at one donation had relatively normal values at the other donations. Further, comparison of computed expected versus observed blood pressure decreases supported the notion of a subsequent regression to the mean among donors with elevated SBP or DBP at Donation 1, 2, or 3.

CONCLUSION

Among individuals who are hypertensive at initial donation, reductions in blood pressure at subsequent donations appear to result from regression to the mean as opposed to a salutary physiologic process.

Arterial Iron Content Is Increased in Patients with High Plasma Ferritin Levels

The association between increased amounts of stored iron and development of cardiovascular disease (CVD) has been recognized for many years. However, basic information on iron content in human arteries is limited. We envision that associations between body iron content and CVD are based on the accumulation of iron in the arteries, possibly leading to the dysfunction of cellular biochemical pathways. This study addresses the very fundamental question of whether there is a relation between body iron content and the level of iron accumulated in arterial tissue. The iron content in human nonatherosclerotic artery samples from patients with high and low body-iron contents estimated from the plasma ferritin concentration were determined by inductively coupled plasma mass spectroscopy in tissue extracts and by histological staining, using a modified Perls reaction to display iron deposits. We found that the arteries contained small but measurable levels of iron. The iron content was significantly higher in tissue from patients with high plasma ferritin (p = 0.026). Histological staining showed the presence of iron deposits. Our results suggest that iron does accumulate in arterial tissue in accordance to the level of stored body iron. Further studies are needed on the distribution of iron in excess to explain the relationship between stored iron and the development of atherosclerosis.

Iron and peripheral arterial disease: revisiting the iron hypothesis in a different light

The relationship between iron status and atherosclerosis has long been a topic of debate in the literature. Despite more than 25 years of research, there is no consensus regarding a causal relationship. To date, the vast majority of studies have focused on iron burden with respect to a hypothesized role in the onset and progression of coronary artery disease. However, the effect of iron in the coronary arterial system may differ mechanistically and therefore clinically from its effect in the peripheral arterial system. This review will summarize the biochemical, pathologic, animal, and clinical research data with respect to iron and atherosclerosis. This background will be expanded upon to provide insights into ongoing studies and paths for future investigations into the role of iron and peripheral arterial disease.

An ethnobotanical study of medicinal plants administered for the treatment of hypertension

INTRODUCTION

The incidence of cardiovascular diseases (CVDs) is very high in human societies and their prevention and treatment are the most important priority in many countries. Hypertension makes an important contribution to the development of CVDs.

OBJECTIVES

This study aimed to collect the ethno-medicinal knowledge of the traditional healers of Shiraz on medicinal plants used in the treatment of hypertension.

MATERIALS AND METHODS

Ethno-medicinal data were collected from September 2012 to July 2013 through direct interview. Twenty-five healers were interviewed using semi-structured questionnaires and their traditional ethno-medicinal knowledge was recorded. Questionnaires were included apothecary personal information, plant local name, plant parts used, method of preparation, season of harvest and traditional use. Data collected from surveys and interviews were transferred to Microsoft Excel 2007 and analyzed.

RESULTS

Analysis of data showed that, 27 medicinal plants from 22 families are used for the treatment of hypertension. The families with most antihypertensive species were Apiaceae (8%), Rosaceae (8%) and Papaveraceae (8%). The most frequently used plant parts were leaves (36%) followed by fruits (30%), aerial part (17%) and branches (7%). The most frequently used preparation method was decoction (95%). Borago officinalis (51.85%), Berberis vulgaris (51.58%) had the highest frequency of mention.

CONCLUSION

The ethno-medicinal survey of medicinal plants recommended by traditional healers for the treatment of hypertension provides new areas of research on the antihypertensive effect of medicinal plants. In the case of safety and effectiveness, they can be refined and processed to produce natural drugs.

Vascular Damage in Patients with Nonalcoholic Fatty Liver Disease: Possible Role of Iron and Ferritin

Non Alcoholic Fatty Liver Disease (NAFLD) is the most common chronic liver disease in Western countries. Recent data indicated that NAFLD is a risk factor by itself contributing to the development of cardiovascular disease independently of classical known risk factors. Hyperferritinemia and mild increased iron stores are frequently observed in patients with NAFLD and several mechanisms have been proposed to explain the role of iron, through oxidative stress and interaction with insulin metabolism, in the development of vascular damage. Moreover, iron depletion has been shown to decrease atherogenesis in experimental models and in humans. This review presents the recent evidence on epidemiology, pathogenesis, and the possible explanation of the role of iron and ferritin in the development of cardiovascular damage in patients with NAFLD, and discusses the possible interplay between metabolic disorders associated with NAFLD and iron in the development of cardiovascular disease.

Effects of Environmental Pollutants on Cellular Iron Homeostasis and Ultimate Links to Human Disease

Chronic disease has increased in the past several decades, and environmental pollutants have been implicated. The magnitude and variety of diseases may indicate the malfunctioning of some basic mechanisms underlying human health. Environmental pollutants demonstrate a capability to complex iron through electronegative functional groups containing oxygen, nitrogen, or sulfur. Cellular exposure to the chemical or its metabolite may cause a loss of requisite functional iron from intracellular sites. The cell is compelled to acquire further iron critical to its survival by activation of iron-responsive proteins and increasing iron import. Iron homeostasis in the exposed cells is altered due to a new equilibrium being established between iron-requiring cells and the inappropriate chelator (the pollutant or its catabolite). Following exposure to environmental pollutants, the perturbation of functional iron homeostasis may be the mechanism leading to adverse biological effects. Understanding the mechanism may lead to intervention methods for this major public health concern.

Regular blood donation may help in the management of hypertension: an observational study on 292 blood donors

BACKGROUND

Hypertension is one of the leading global risks for cardiovascular events worldwide. There is preliminary evidence that regular blood donation may be beneficial.

STUDY DESIGN AND METHODS

Unselected blood donors were included in this observational study. Blood pressure (BP) was measured before and after blood donation, with participants donating between one and four occasions in a 1-year study period.

RESULTS

In this study, 292 donors were enrolled. At baseline, 146 had elevated BP (> 140/90 mmHg). In hypertensives, after four blood donations, systolic and diastolic blood pressure (SBP and DBP, respectively) decreased from a mean of 155.9 ± 13.0 to 143.7 ± 15.0 mmHg and from 91.4 ± 9.2 to 84.5 ± 9.3 mmHg, respectively (each p < 0.001). There was a clear dose effect with decreasing BP by the increasing number of blood donations. After at least four blood donations, donors with Stage II hypertensive baseline values (≥ 160 mmHg SBP and/or ≥ 100 mmHg DBP) were found to have the most marked reduction in BP, with 17.1 mmHg (95% confidence interval [CI], -23.2 to -11.0; p < 0.0001) and 11.7 mmHg (95% CI, -17.1 to -6.1; p = 0.0006) for SBP and DBP, respectively. The decrease in BP was not significantly associated with changes of blood count or variables of iron metabolism.

CONCLUSIONS

Regular blood donation is associated with pronounced decreases of BP in hypertensives. This beneficial effect of blood donation may open a new door regarding community health care and cost reduction in the treatment of hypertension.

Regular blood donation improves endothelial function in adult males

OBJECTIVE

Endothelial dysfunction, secondary to systemic inflammation and oxidative stress, is known to play a major role in the development and progression of atherosclerosis. It is hypothesized that the lower incidence of coronary artery disease in the premenopausal period in females when compared with males is associated with regular menstrual blood loss. We investigated whether regular blood donation (BD) is associated with improved endothelial function in healthy adult males.

METHODS

Fifty young healthy male volunteers volunteers with a mean age of 30 ± 6 years without overt cardiovascular disease were enrolled to participate in serial consecutive BDs. Serum iron levels as oxidative stress parameters, flow-mediated dilatation (FMD) for endothelial function, 24-h mean diastolic blood pressure for peripheral vascular resistance identification, and high-sensitivity C-reactive protein (hs-CRP) levels as systemic inflammatory markers were evaluated before and after BD. This study used a prospective observational cohort design. Patients with cardiovascular and inflammatory diseases were excluded.

RESULTS

BD was found to improve FMD steadily and significantly when compared with the baseline (mean ± SD: 9.9% ± 3.8%, 10.44% ± 3.9%, 10.65% ± 3.9%, and 10.75 ± 3.9%, respectively, p=0.15, p=0.02, p=0.006 as compared with the baseline). A steady decrease was identified in hs-CRP levels after serial BDs, although this decrease was not statistically significant in the all phases (2.96 ± 3.3 mg/L, 2.26 ± 1.5 mg/L, and 2.12 ± 1.5 mg/L, respectively, p=0.829, p=0.558). The 24-h mean diastolic blood pressures were significantly lower in the chronic phase (77 ± 9 mm Hg, 75 ± 7 mm Hg, and 72 ± 8 mm Hg, respectively, p=0.50, p=0.003), whereas there was no significant change in iron levels in the acute and chronic phases (66 ± 32 mg/dL, 72 ± 43 mg/dL, and 68 ± 33 mg/dL, respectively, p=1.000, p=1.000).

CONCLUSION

The results of the study indicate that regular BD improves endothelial function.

Iron and hepcidin as risk factors in atherosclerosis: what do the genes say?

Background

Previous reports suggested a role for iron and hepcidin in atherosclerosis. Here, we evaluated the causality of these associations from a genetic perspective via (i) a Mendelian randomization (MR) approach, (ii) study of association of atherosclerosis-related single nucleotide polymorphisms (SNPs) with iron and hepcidin, and (iii) estimation of genomic correlations between hepcidin, iron and atherosclerosis.

Results

Analyses were performed in a general population sample. Iron parameters (serum iron, serum ferritin, total iron-binding capacity and transferrin saturation), serum hepcidin and genome-wide SNP data were available for N = 1,819; non-invasive measurements of atherosclerosis (NIMA), i.e., presence of plaque, intima media thickness and ankle-brachial index (ABI), for N = 549. For the MR, we used 12 iron-related SNPs that were previously identified in a genome-wide association meta-analysis on iron status, and assessed associations of individual SNPs and quartiles of a multi-SNP score with NIMA. Quartile 4 versus quartile 1 of the multi-SNP score showed directionally consistent associations with the hypothesized direction of effect for all NIMA in women, indicating that increased body iron status is a risk factor for atherosclerosis in women. We observed no single SNP associations that fit the hypothesized directions of effect between iron and NIMA, except for rs651007, associated with decreased ferritin concentration and decreased atherosclerosis risk. Two of six NIMA-related SNPs showed association with the ratio hepcidin/ferritin, suggesting that an increased hepcidin/ferritin ratio increases atherosclerosis risk. Genomic correlations were close to zero, except for hepcidin and ferritin with ABI at rest [−0.27 (SE 0.34) and −0.22 (SE 0.35), respectively] and ABI after exercise [−0.29 (SE 0.34) and −0.30 (0.35), respectively]. The negative sign indicates an increased atherosclerosis risk with increased hepcidin and ferritin concentrations.

Conclusions

Our results suggest a potential causal role for hepcidin and ferritin in atherosclerosis, and may indicate that iron status is causally related to atherosclerosis in women.

Electronic supplementary material

The online version of this article (doi:10.1186/s12863-015-0246-4) contains supplementary material, which is available to authorized users.

Risk of illness, hospitalization and death in a cohort of blood donors in Italy

OBJECTIVE

The aim of this study was to determine whether blood donors (BDs), compared with non blood donors (nBDs), present significant differences in risk of illness, hospitalization and death.

METHODS

All subjects included in the database of the Association of Voluntary Italian Blood Donors of Ferrara entered the study. The analysis only included residents who donated at least once. For each BD, four age- and sex-matched non-donor controls were selected from the master archive of the Province of Ferrara. Then, all hospitalizations of BDs and controls from January 2005 to December 2010 were extracted from the hospital admission and discharge database of the region.

RESULTS

During the considered period, 26,140 hospital admissions in BDs and 98,685 in controls were recorded; 11,862 individual BDs and 43,138 nBDs. Compared with controls, BDs were characterized by older age, lower average number of admissions and diagnoses, Charlson comorbidity index score, shorter hospital length-of-stay (LOS), lower mortality rates and higher age at death. Age at death was significantly higher for BDs with longer duration and higher number of donations. In particular, blood donation was not related to an increased risk of malignancies. The main limitation of this study is potential selection bias (i.e. a healthy donor effect). Matching with the control population also has its limitations.

CONCLUSIONS

This study confirms that BDs have a lower risk of hospitalization, and, more specifically, do not have an increased risk of malignancies, leukemias, lymphomas and myeloma.

Atherogenesis and iron: from epidemiology to cellular level

Iron accumulates in human atherosclerotic lesions but whether it is a cause or simply a downstream consequence of the atheroma formation has been an open question for decades. According to the so called "iron hypothesis," iron is believed to be detrimental for the cardiovascular system, thus promoting atherosclerosis development and progression. Iron, in its catalytically active form, can participate in the generation of reactive oxygen species and induce lipid-peroxidation, triggering endothelial activation, smooth muscle cell proliferation and macrophage activation; all of these processes are considered to be proatherogenic. On the other hand, the observation that hemochromatotic patients, affected by life-long iron overload, do not show any increased incidence of atherosclerosis is perceived as the most convincing evidence against the "iron hypothesis." Epidemiological studies and data from animal models provided conflicting evidences about the role of iron in atherogenesis. Therefore, more careful studies are needed in which issues like the source and the compartmentalization of iron will be addressed. This review article summarizes what we have learnt about iron and atherosclerosis from epidemiological studies, animal models and cellular systems and highlights the rather contributory than innocent role of iron in atherogenesis.

Iron deficiency anemia in heart failure

Anemia and iron deficiency are quite prevalent in patients with heart failure (HF) and may overlap. Both anemia and iron deficiency are associated with worse symptoms and adverse clinical outcomes. In the past few years, there has been an enormous interest in the subject of iron deficiency and its management in patients with HF. In this review, the etiology and relevance of iron deficiency, iron metabolism in the setting of HF, studies on iron supplementation in patients with HF and potential cardiovascular effects of subclinical iron overload are discussed.

Iron, human growth, and the global epidemic of obesity

Iron is an essential nutrient utilized in almost every aspect of cell function and its availability has previously limited life. Those same properties which allow iron to function as a catalyst in the reactions of life also present a threat via generation of oxygen-based free radicals. Accordingly; life exists at the interface of iron-deficiency and iron-sufficiency. We propose that: (1) human life is no longer positioned at the limits of iron availability following several decades of fortification and supplementation and there is now an overabundance of the metal among individuals of many societies; (2) this increased iron availability exerts a positive effect on growth by targeting molecules critical in regulating the progression of the cell cycle; there is increased growth in humans provided greater amounts of this metal; and indices of obesity can positively correlate with body stores of iron; and (3) diseases of obesity reflect this over-abundance of iron. Testing potential associations between iron availability and both obesity and obesity-related diseases in populations will be difficult since fortification and supplementation is so extensively practiced.

Cardiovascular benefits of phlebotomy: relationship to changes in hemorheological variables

Renewed interest in the age-old concept of “bloodletting”, a therapeutic approach practiced until as recently as the 19th century, has been stimulated by the knowledge that blood loss, such as following regular donation, is associated with significant reductions in key hemorheological variables, including whole blood viscosity (WBV), plasma viscosity, hematocrit and fibrinogen. An elevated WBV appears to be both a strong predictor of cardiovascular disease and an important factor in the development of atherosclerosis. Elevated WBV through wall shear stress is the most direct physiological parameter that influences the rupture and erosion of vulnerable plaques. In addition to WBV reduction, phlebotomy may reduce an individual’s cardiovascular risk through reductions in excessive iron, oxidative stress and inflammation. Reflecting these findings, blood donation in males has shown significant drops in the incidence of cardiovascular events, as well as in procedures such as percutaneous transluminal coronary angioplasty and coronary artery bypass grafting. Collectively, the available data on the benefits of therapeutic phlebotomy point to the importance of monitoring WBV as part of a cardiovascular risk factor, along with other risk-modifying measures, whenever an increased cardiovascular risk is detected. The development of a scanning capillary tube viscometer allows the measurement of WBV in a clinical setting, which can prove to be valuable in providing an early warning sign of an increased risk of cardiovascular disease.

Iron and cardiac ischemia: a natural, quasi-random experiment comparing eligible with disqualified blood donors

BACKGROUND

The theory that elevated iron stores can induce vascular injury and ischemia remains controversial. We conducted a cohort study of the effect of blood donation on the risk of coronary heart disease (CHD) by taking advantage of the quasi-random exclusion of donors who obtained a falsely reactive test for a transmissible disease (TD) marker.

STUDY DESIGN AND METHODS

Whole blood donors who were permanently disqualified because of a false-reactive test between 1990 and 2007 in the province of Quebec were compared to donors who remained eligible, matched for baseline characteristics. The incidence of CHD after entry into the study was determined through hospitalization and death records. We compared eligible and disqualified donors using an "intention-to-treat" framework.

RESULTS

Overall, 12,357 donors who were permanently disqualified were followed for 124,123 person-years of observation, plus 50,889 donors who remained eligible (516,823 person-years). On average, donors who remained eligible made 0.36 donation/year during follow-up and had an incidence of hospitalizations or deaths attributable to CHD of 3.60/1000 person-years, compared to 3.52 among permanently disqualified donors (rate ratio, 1.02; 95% confidence interval, 0.92-1.13).

CONCLUSION

Donors who remained eligible did not have a lower risk of CHD, compared to donors who were permanently disqualified due to a false-reactive TD marker. Because of the quasi-random nature of false-reactive screening tests, this natural experiment has a level of validity approaching that of a randomized trial evaluating the effect of regular blood donation on CHD risk. These results do not support the iron hypothesis.

Serum ferritin-a novel risk factor in acute myocardial infarction

BACKGROUND

A possible association between body iron status and risk of coronary heart disease (CHD) has been found to be controversial from the data obtained from various studies.

OBJECTIVES

To study the relationship of serum ferritin with acute myocardial infarction (AMI) in univariate and multivariate analysis and to assess the relationship of high serum ferritin with established conventional risk factors.

METHODS

Hospital based case-control study of 75 cases of AMI, and 75 age and equal number of age, and gender-matched controls without having AMI in the age group of 30-70 years.

RESULTS

Median serum ferritin levels were significantly higher in cases (220 μg/L) than controls (155 μg/L) (P ≤ 0.0001. In univariate analysis in addition to ferritin > 200 μg/L (odds ratio [OR] 6.71, 95% confidence interval [CI] = 3.22-12.89, P<0.05), diabetes (OR=7.68, 95% CI=2.95-19.13, P<0.05), hypertension (HTN) (OR=2.36, 95% CI=1.02-5.14, P<0.05) high-density lipoprotein (HDL) < 35 mg/dL (OR = 11.9, 95% CI = 2.66-52.57, P<0.05) and smoking (OR=2.17, 95% CI = 1.12-3.87, P< 0.05) were found to be significantly associated with AMI. After controlling for all conventional risk factors, in multiple logistic regression analysis, high ferritin was significantly associated with AMI. (adjusted OR=5.72, 95% CI=2.16-15.17, P < 0.001). Serum ferritin was significantly higher in diabetics than non-diabetics (P < 0.01).

CONCLUSION

High serum ferritin is strongly and independently associated with AMI.

Iron deficiency in community-dwelling US adults with self-reported heart failure in the National Health and Nutrition Examination Survey III: prevalence and associations with anemia and inflammation

BACKGROUND

Iron deficiency has been proposed as a potential therapeutic target in heart failure, but its prevalence and association with anemia and clinical outcomes in community-dwelling adults with heart failure have not been well characterized.

METHODS AND RESULTS

Using data from the Third National Health and Nutrition Examination Survey, we evaluated the associations between iron deficiency, hemoglobin, C-reactive protein (CRP), and all-cause and cardiovascular mortality in 574 adults with self-reported heart failure. Iron deficiency was defined in both absolute and functional terms as a ferritin level <100 μg/L or between 100 and 299 μg/L if the transferrin saturation was <20%. Iron deficiency was present in 61.3% of participants and was associated with reduced mean hemoglobin (13.6 versus 14.2 g/dL, P=0.007) and increased mean CRP (0.95 versus 0.63 mg/dL, P=0.04). Over a median of 6.7 years of follow-up, there were 300 all-cause deaths, 193 of which were from cardiovascular causes. In age- and sex-adjusted Cox proportional hazards models, hemoglobin, CRP, and transferrin saturation but not iron deficiency were significantly associated with all-cause and cardiovascular mortality. In multivariate models, hemoglobin remained an independent predictor of cardiovascular mortality, whereas CRP remained an independent predictor of both all-cause and cardiovascular mortality.

CONCLUSIONS

Iron deficiency is common in heart failure and is associated with decreased hemoglobin and increased CRP. In multivariate analysis, hemoglobin was associated with cardiovascular mortality while CRP was associated with both all-cause and cardiovascular mortality. Iron deficiency was not associated with all-cause or cardiovascular mortality in this cohort.

Treatment of anemia in heart failure: potential risks and benefits of intravenous iron therapy in cardiovascular disease

Iron-deficiency anemia is common in patients with heart failure (HF), but the optimum diagnostic tests to detect iron deficiency and the treatment options to replete iron have not been fully characterized. Recent studies in patients with HF indicate that intravenous iron can rapidly replenish iron stores in patients having iron-deficiency anemia, with resultant increased hemoglobin levels and improved functional capacity. Preliminary data from a subgroup analysis also suggest that supplemental intravenous iron therapy can improve functional capacity even in those subjects without anemia. The mechanisms responsible for this observation are not fully characterized, but may be related to beneficial effects of iron supplementation on mitochondrial respiration in skeletal muscle. The long-term safety of using intravenous iron supplementation in HF populations is not known. Iron is a known pro-oxidant factor that can inhibit nitric oxide signaling and irreversibly injury cells. Increased iron stores are associated with vascular endothelial dysfunction and increased risk of coronary heart disease events. Additional clinical trials are needed to more fully characterize the therapeutic potential and safety of intravenous iron in HF patients.

Use of mental simulations to change theory of planned behaviour variables

OBJECTIVES

The predictive validity of the theory of planned behaviour is well established, but much less is known about: (a) whether there are causal relationships between key components of the model and (b) how to go about changing the theory of planned behaviour variables. This study tested the ability of outcome and process simulations to change variables specified in the theory of planned behaviour in relation to blood donation.

DESIGN

Participants (N=146) were randomized to one of four conditions: outcome simulation only, process simulation only, process-plus-outcome simulation and a distractor control condition. The dependent variables were state anxiety, and intention attitude, subjective norm and perceived control from the theory of planned behaviour.

METHODS

Participants were asked to empty their mind and visualize themselves: (a) after donating blood (outcome manipulation), (b) preparing to donate blood (process manipulation), (c) both preparing to donate blood and after having donated blood (process-plus-outcome manipulation) or (d) both preparing to get a high mark and after having got a high mark on their course (control condition). Following mental rehearsal, participants completed the dependent variables.

RESULTS

There were no main effects of outcome simulation, but process simulation successfully increased intention, subjective norm and perceived control. There was also a significant outcome simulation x process simulation interaction for attitude. The effect of the process manipulation on intention was mediated by subjective norm and perceived control.

CONCLUSIONS

The findings show promise for the use of mental simulations in changing cognitions and further research is required to extend the present findings to other health behaviours.

Insights into the ethnic differences in serum ferritin between black and white US adult men

Although higher serum ferritin (SF) concentrations have been consistently observed among blacks, despite their lower hemoglobin (Hb) concentrations compared with whites, few studies attempted to explain this SF difference. To determine the possible factors contributing to the observed SF difference between blacks and whites, 1,938 non-Hispanic white (NHW) and 1,616 non-Hispanic black (NHB) male subjects, aged 20-65 years were selected from the third National Health and Nutrition Examination Survey (NHANES III). Multiple regression analysis was used to examine the contribution of dietary, biochemical, and socioeconomic variables to the observed SF difference between the two groups. NHB subjects showed a continuing, significantly higher SF concentration compared with NHW subjects at each age group. Age, serum total protein, mean cell volume (MCV), and gamma glutamyl transferase (GGT) were positively associated with SF, whereas percent energy from carbohydrate and fat, calcium intake, serum alpha-carotene, and iron binding capacity (TIBC) were inversely associated with SF (P < 0.01). After excluding subjects with abnormal serum total protein, TIBC and GGT levels from the analysis (the final regression model), the SF difference dropped to 3.95 microg/l (initial difference = 37.1 microg/l) between NHWs and NHBs. The results suggest that the oft-noted black-white SF difference is a result of factors including overall nutrition and health, iron status, and hepatic well-being. Higher SF, low Hb, and reduced TIBC level observed in blacks are consistent with the definition of anemia of chronic disease (ACD). Future investigations are needed to confirm the role of ACD in the black-white SF difference.

Evidence-based criteria for the care and selection of blood donors, with some comments on the relationship to blood supply, and emphasis on the management of donation-induced iron depletion

Blood Services, which, in the UK, spend over 0.5% of the NHS budget, are generally subject to quality, regulatory, economic and political authority. As only persons in good health should give blood, Services have refined donor selection criteria and aim to base them on evidence; but they also have to balance the number of donations collected with product demand. Applying selection criteria inevitably leads to deferrals, which donors experience very negatively. Compared with successful donors, even temporary deferrals reduce return rates significantly, especially of first attenders. In order to encourage donor return and sustain supplies, selection criteria should be optimal. However, a major tool for managing patients--evidence from randomized controlled trials (RCTs)--cannot apply to donor selection, so criteria have to be defined by alternatives, such as clinical studies, epidemiology and even what experts deem to be pathophysiologically feasible. The recommended volume of blood taken from each donor at each attendance (450 mL, which was based on old studies) was increased because of greater processing losses (buffy-coat derived platelets, leucofiltration etc.). Although faint rates and donation-induced iron depletion are reduced by lowering bleeding volume and bleeding less frequently, other optimizing strategies including iron supplementation have been trialled and could be enhanced by more RCTs. Better but more complex indicators of donor iron status than one-off Hb thresholds are possible. Regulators and decision-makers must encourage more studies. This review does not consider aphaeresis donors of blood components other than red cells in detail, or the prevention of transfusion-transmitted infections.

The role of zinc, copper and iron in the pathogenesis of diabetes and diabetic complications: therapeutic effects by chelators

Zinc (Zn), copper (Cu) and iron (Fe) are essential minerals that are required for a variety of biomolecules to maintain the normal structure, function, and proliferation of cells. These metals can be toxic in excessive amounts, especially in certain genetic disorders. The homeostasis of these trace elements results from a tightly coordinated regulation by different proteins involved in their uptake, excretion and intracellular storage/trafficking. Through the Fenton reaction, Cu and Fe under a non protein-binding condition, can generate various reactive oxygen species, damaging tissues or cells. Abnormal metabolism of Zn, Cu and Fe can lead to several chronic pathogenesis, such as diabetes or diabetic complications. These pathogenic conditions appear to be prevalent in Zn and Cu deficiency, as well as Cu and Fe overload. In the Fe and Cu overloading conditions, Fe and Cu chelating drugs could be used to control diabetes and diabetic complications. The essentiality, toxicity and roles of these metals in the pathogenesis of diabetes and diabetic complications are discussed.

Blood donation, body iron status and carotid intima-media thickness

Iron could promote free radical formation, which may lead to injury of the arterial wall and atherosclerosis. Blood donation may reduce cardiovascular risk by lowering body iron status. We collected data on blood donation history and intima-media thickness of the common carotid artery (CIMT) in 819 subjects (50-70 years), who were recruited from municipal and blood bank registries in The Netherlands. Serum iron parameters were assessed, including non-transferrin bound iron (NTBI) that has recently been found in conditions of iron overload. Serum ferritin was lower in current donors (n=443; 44 microg/L) than in ex-donors (n=120; 114 microg/L) and never-donors (n=256; 124 microg/L, P for trend <0.001). For NTBI, values were 2.33, 2.54, and 2.51 micromol/L, respectively (P<0.05). CIMT was slightly reduced in frequent donors (i.e., > or =49 times during life or > or =2 times per year), although not statistically significant. CIMT was not significantly related to NTBI. Frequent blood donation, resulting in lowered body iron, might give some protection against accelerated atherosclerosis.

Improving health profile of blood donors as a consequence of transfusion safety efforts

BACKGROUND

Transfusion safety rests heavily on the health of blood donors. Although they are perceived as being healthier than average, little is known about their long-term disease patterns and to which extent the blood banks' continuous efforts to optimize donor selection has resulted in improvements. Mortality and cancer incidence among blood donors in Sweden and Denmark was investigated.

STUDY DESIGN AND METHODS

All computerized blood bank databases were compiled into one database, which was linked to national population and health data registers. With a retrospective cohort study design, 1,110,329 blood donors were followed for up to 35 years from first computer-registered blood donation to death, emigration, or December 31, 2002. Standardized mortality and incidence ratios expressed relative risk of death and cancer comparing blood donors to the general population.

RESULTS

Blood donors had an overall mortality 30 percent lower (99% confidence interval [CI] 29%-31%) and cancer incidence 4 percent lower (99% CI 2%-5%) than the background population. Mortality rates and cancer incidence were lowest for outcomes that are recognized as being related to lifestyle factors such as smoking or to the selection criteria for blood donation. Blood donors recruited in more recent years exhibited a lower relative mortality than those who started earlier.

CONCLUSION

Blood donors enjoy better than average health. Explicit and informal requirements for blood donation in Scandinavia, although mostly of a simple nature, have successfully refined the selection of a particularly healthy subpopulation.

Iron and thrombosis

Although essential for cell physiology, an increase or depletion of body iron has harmful effects on health. Apart from iron deficiency anemia and iron overload-related organ tissue damage, there are increasing evidences that body iron status is implicated in atherosclerotic cardiovascular diseases. The hypothesis formulated in 1981 that iron depletion may protect against cardiovascular events is intriguing and has generated a significant debate in the last two decades. Indeed, to study this phenomenon, several investigators have tried to design appropriate experimental and clinical studies and to identify useful biochemical and genetic markers of iron status. The results of the literature on the effect of iron deficiency and overload on vascular health are critically reviewed in this study from a pathogenic and clinical point of view.