The association between the levels of serum ferritin and sex hormones in a large scale of Chinese male population

Relationship between Iron Deficiency and Thyroid Function: A Systematic Review and Meta-Analysis

Objective: Iron deficiency (ID) is the most prevalent nutritional deficiency worldwide. Low levels of serum ferritin (SF) could affect the thyroid gland and its functioning. The purpose of this systematic review and meta-analysis is to summarize the main currently available evidence and analyze data on the relationship between ID and thyroid function. Methods: This study included all articles evaluating the relationship between ID and thyroid function. Quality assessment was performed using Cambridge Quality Checklists. The search strategy included the following combination of Medical Subjects Headings terms and keywords: "iron deficiency", "thyroid function", "thyroid disease", "thyroid dysfunction", and "hypothyroidism". A meta-analysis was performed to evaluate whether thyroid stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) levels differed between patients with ID and healthy controls without ID. For statistical comparison between cases and controls, the mean difference (MD) was calculated, and a subgroup analysis of pregnant and non-pregnant women was performed. Cochran's Q testing and heterogeneity indices (I2) were used to assess statistical heterogeneity. Sensitivity analysis and publication bias analyses were also performed, both qualitatively and quantitatively. Finally, a meta-regression analysis was performed to evaluate the correlation between serum TSH or FT4 levels and SF in the study population. Results: Ten cross-sectional studies were identified and reviewed. Patients with ID showed TSH (MD: -0.24 mIU/L; 95% CI -0.41, -0.07; I2 = 100%, p = 0.005), FT4 (MD: -1.18 pmol/L; 95% CI -1.43, -0.94; I2 = 99%, p < 0.000001), and FT3 (MD: -0.22 pmol/L; 95% CI -0.32, -0.12; I2 = 99%, p < 0.00001) levels that were significantly lower. Subgroup analysis confirmed significantly lower TSH, FT4, and FT3 levels in pregnant women. Non-pregnant women showed significantly lower serum FT4 and FT3 levels but no difference in TSH values. Meta-regression analysis showed that serum TSH and FT4 levels were positively correlated with SF levels. Our systematic review of the literature found that ID significantly increases the prevalence of thyroid autoantibody (anti-thyroglobulin antibodies and anti-thyroid peroxidase antibodies) positivity both individually and collectively. Conclusion: Studies currently published in the literature indicate a possible relationship between ID, thyroid function, and autoimmunity, especially in some patient groups. Data analysis shows that thyroid hormone levels are lower in patients with ID and, in particular, in pregnant women. Further studies are needed to understand the role played by iron in thyroid metabolism.

Association between serum ferritin and liver stiffness in adults aged ≥20 years: A cross-sectional study based on NHANES

The importance of serum ferritin has been demonstrated in many liver diseases, but its relationship with liver stiffness remains unclear. The objective of this study was to investigate the association between serum ferritin levels and participants' liver stiffness measurement (LSM) in the United States population. We conducted a screening of participants from National Health and Nutrition Examination Survey (NHANES) 2017.1 to 2020.3 to ensure that participants included in this study had complete serum ferritin and LSM information. Association between the independent variable (serum ferritin) and the dependent variable (LSM) was investigated by multiple linear regression and subgroup analysis was performed to identify sensitive individuals, and we subsequently assessed whether there was a non-linear relationship between the 2 using smoothed curve fitting and threshold effect models. The final 7143 participants were included in this study. There was a positive association between participants' serum ferritin concentration and LSM, with an effect value of (β = 0.0007, 95% confidence interval (CI): 0.0002-0.0011) in the all-adjusted model. The smoothing curve and threshold effect models indicated a non-linear positive correlation between serum ferritin and LSM, which was more pronounced when serum ferritin concentration exceeded 440 ng/mL. Subsequent subgroup analysis showed that this positive correlation was more pronounced in males (β = 0.0007, 95% CI: 0.0001-0.0012), age >60 years (β = 0.00015, 95% CI: 0.0007-0.0023), black participants (β = 0.00018, 95% CI: 0.0009-0.0026), and participants with body mass index (BMI) <25 kg/m2 (β = 0.00012, 95% CI: 0.0005-0.0020). In U.S. adults, there was a positive correlation between serum ferritin levels and liver stiffness, which was more pronounced when serum ferritin exceeded 440 ng/mL. Our study suggested that regular serum ferritin testing would be beneficial in monitoring changes in liver stiffness. Male, age >60 years, black participants, and those with a BMI < 25 kg/m2 should be of greater consideration.

Sex difference in the association between blood alcohol concentration and serum ferritin

Introduction

The sex difference in alcohol use disorder (AUD) is ingrained in distinctive neurobiological responses between men and women, which necessitates further investigation for a more tailored management.

Methods

Minding the findings of iron dysregulation in AUD and the sex difference in iron homeostasis in multiple physiological and pathological settings, we examined the sex difference in the association between serum ferritin and blood alcohol concentration (BAC) in intoxicated males (n = 125) and females (n = 59). We included patients with both serum ferritin tested of any value and a BAC above the level of detection during the same hospital admission period. We investigated sex difference in the relationship between BAC, serum ferritin and liver enzymes in intoxicated critically ill and noncritically ill patients.

Results

We found a negative association between serum ferritin and BAC in critically ill, intoxicated females [R2 = 0.44, F(1,14) = 11.02, p = 0.005], with much attenuated serum ferritin in females compared to their male counterparts (194.5 ± 280.4 vs. 806.3 ± 3405.7 ng/L, p = 0.002). We found a positive association between serum ferritin and liver enzymes [alanine transaminase (ALT) and aspartate transferase (AST)] in critically ill intoxicated females [ALT: R2 = 0.48, F(1,10) = 9.1, p = 0.013; AST: R2 = 0.68, F(1,10) = 21.2, p = 0.001] and in noncritically ill intoxicated males [ALT: R2 = 0.1, F(1,83) = 9.4, p = 0.003; AST: R2 = 0.1, F(1,78) = 10.5, p = 0.002]. The effect of BAC on serum ferritin was not mediated by ALT [indirect effect: (B = 0.13, p = 0.1)]. We also found a significant effect of sex, anemia, intensive care unit (ICU) admission and mortality on serum ferritin.

Discussion

Our results suggest that high BAC in intoxicated female patients is associated with attenuated serum ferritin levels, questioning the role of low serum ferritin in female vulnerability to alcohol.

The Clinical Utility of ABO and RHD Systems as Potential Indicators of Health Status, a Preliminary Study in Greek Population

Objective: The objective of this study is to further highlight the differences between different ABO blood groups and Rhesus types with health biomarkers. Methods: In total 150 active healthy blood donors participated in our study comprising of 80 males from 19–61 years and 70 females aged from 21 to 64. Participants carrying blood group A were 55 individuals, blood group B 32, blood group O 51, and blood group AB 12, RHD+ 132, and RHD- 18. All the volunteer regular blood donors were selected recognizing them as a healthy population excluding drug and supplements intake. Their blood samples were analyzed just before blood donation for biochemical, hematological, and antioxidant markers. Statistical computations were performed using the SPSS tool, specifically, the one-way ANOVA test, Chi-square statistics, and logistic regression were used as statistical models. Results: O blood donors presented better iron absorption and the worst lipid profile. Indeed, a significant trend of high atheromatic index values revealed an increased risk for hyperlipidemia, in contrast with blood group A presenting a better lipid profile with lower atheromatic index values. There was also a gender related association for blood group A compared with O that was further highlighted using binary logistic regression. Conclusion: In this study, a significant difference was observed among the ABO blood groups in several of the examined biochemical and hematological biomarkers. O blood group appeared different behavior in comparison to all the tested blood groups and furthermore the RHD-group presented a better lipid profile in comparison to the RHD+ group. In order to obtain a more comprehensive view of the correlation between the ABO blood group and biochemical markers, further studies are required.

Waist-to-height ratio, an optimal anthropometric indicator for metabolic dysfunction associated fatty liver disease in the Western Chinese male population

Background

Non-alcoholic fatty liver disease (NAFLD) has been entitled as metabolic-dysfunction associated fatty liver disease (MAFLD). Therefore anthropometric indicators of adiposity may provide a non-invasive predictive and diagnostic tool for this disease. This study intended to validate and compare the MAFLD predictive and diagnostic capability of eight anthropometric indicators.

Methods

The study involved a population-based retrospective cross-sectional design. The Fangchenggang area male health and examination survey (FAMHES) was used to collect data of eight anthropometric indicators, involving body mass index (BMI), waist-to-height ratio (WHtR), waist-hip ratio (WHR), body adiposity index (BAI), cardiometabolic index (CMI), lipid accumulation product (LAP), visceral adiposity index (VAI), and abdominal volume index (AVI). Receiver operating characteristics (ROC) curves and the respective areas under the curves (AUCs) were utilized to compare the diagnostic capacity of each indicator for MAFLD and to determine the optimal cutoff points. Binary logistic regression analysis was applied to identify the odds ratios (OR) with 95% confidence intervals (95% CI) for all anthropometric indicators and MAFLD. The Spearman rank correlation coefficients of anthropometric indicators, sex hormones, and MAFLD were also calculated.

Results

All selected anthropometric indicators were significantly associated with MAFLD (P < 0.001), with an AUC above 0.79. LAP had the highest AUC [0.868 (95% CI, 0.853–0.883)], followed by WHtR [0.863 (95% CI, 0.848–0.879)] and AVI [0.859 (95% CI, 0.843–0.874)]. The cutoff values for WHtR, LAP and AVI were 0.49, 24.29, and 13.61, respectively. WHtR [OR 22.181 (95% CI, 16.216–30.340)] had the strongest association with MAFLD, regardless of potential confounders. Among all the anthropometric indicators, the strongest association was seen between LAP and sex hormones.

Conclusion

All anthropometric indicators were associated with MAFLD. WHtR was identified as the strongest predictor of MAFLD in young Chinese males, followed by LAP and AVI. The strongest association was found between LAP and sex hormones.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01568-9.

A double-blind, controlled, crossover trial of amlodipine on iron overload status in transfusion dependent β-thalassemia patients

BACKGROUND AND AIM

This study examined whether administration of amlodipine could improve myocardial iron loading status in patients with transfusion dependent β-thalassemia (TDT), through a placebo-controlled, crossover study.

METHODS

Amlodipine (5 mg, daily) or placebo were prescribed to all patients (n = 19) for 6 months, and after a 2-week washout period, patients were crossed over to the other group. The efficacy of amlodipine on iron loading was assessed by measuring myocardial T2*-weighted magnetic resonance imaging (MRI T2*, millisecond [ms]) and serum ferritin (ng/mL).

RESULTS

Seventeen patients completed the study. The mean ± standard deviation [SD] of myocardial MRI T2* at baseline was 9.83 ± 2.67 ms Myocardial MRI T2* value rose to 11.44 ± 4.14 ms post amlodipine treatment in all patients. After placebo, myocardial MRI T2* value reached 10.29 ± 4.01 ms After controlling the baseline measures, Hedges's g for ferritin and myocardial MRI T2* outcomes were estimated 3.84 (95% confidence interval [CI] 2.68 to 4.97) and -1.80 (95% CI -2.58 to -0.10), respectively.

CONCLUSION

Amlodipine might improve myocardial MRI T2* and serum ferritin level compared to placebo. However, larger clinical studies are needed to confirm the results.

Effects of Dietary or Supplementary Micronutrients on Sex Hormones and IGF-1 in Middle and Older Age: A Systematic Review and Meta-Analysis

Observational research suggests that micronutrients may be protective for sarcopenia, a key health issue during ageing, potentially via effects on hormone synthesis and metabolism. We aimed to carry out a systematic review of RCTs investigating effects of increasing dietary or supplemental micronutrient intake on sex hormones and IGF-1 in individuals aged 45 years or older. We searched MEDLINE, EMBASE and Cochrane databases for RCTs reporting the effects of different micronutrients (vitamins A, C, D, or E; carotenoids; iron; copper; zinc; magnesium; selenium; and potassium) on sex hormones or IGF-1. Of the 26 RCTs identified, nine examined effects of vitamin D, nine of multi-nutrients, four of carotenoids, two of selenium, one of zinc, and one of vitamin E. For IGF-1 increasing vitamin D (MD: -0.53 nmol/L, 95% CI: -1.58, 0.52), multi-nutrients (MD: 0.60 nmol/L, 95% CI -1.12 to 2.33) and carotenoids (MD -1.32 nmol/L; 95% CI -2.76 to 0.11) had no significant effect on circulating concentrations. No significant effects on sex hormones of other micronutrients were found, but data were very limited. All trials had significant methodological limitations making effects of micronutrient supplementation on sex hormones unclear. Further high quality RCTs with physiological doses of micronutrients in people with low baseline intakes or circulating concentrations, using robust methodology, are required to assess effects of supplementation adequately.

Iron and Advanced Glycation End Products: Emerging Role of Iron in Androgen Deficiency in Obesity

The literature suggests a bidirectional relationship between testosterone (T) and iron, but mechanisms underlying this relationship remain unclear. We investigated effects of iron on advanced glycation end products (AGEs) in obesity-related androgen deficiency. In total, 111 men were recruited, and iron biomarkers and N(ɛ)-(carboxymethyl)lysine (CML) were measured. In an animal study, rats were fed a 50% high-fat diet (HFD) with (0.25, 1, and 2 g ferric iron/kg diet) or without ferric citrate for 12 weeks. Obese rats supplemented with >1 g iron/kg diet had decreased testicular total T compared to HFD alone. Immunohistochemical staining showed that >1 g of ferric iron increased iron and AGE retention in testicular interstitial tissues, which is associated with increased expression of the receptor for AGEs (RAGE), tumor necrosis factor-α, and nitric oxide. Compared with normal weight, overweight/obese men had lower T levels and higher rates of hypogonadism (19% vs. 11.3%) and iron overload (29.8% vs.15.9%). A correlation analysis showed serum total T was positively correlated with transferrin saturation (r = 0.242, p = 0.007) and cathepsin D (r = 0.330, p = 0.001), but negatively correlated with red blood cell aggregation (r = −0.419, p<0.0001) and CML (r = −0.209, p < 0.05). In conclusion, AGEs may partially explain the underlying relationship between dysregulated iron and T deficiency.

Prevalence of Iron deficiency in Lebanese schoolchildren

BACKGROUND

The prevalence of iron deficiency in the Lebanese pediatric population is unknown. The aim of this study is to estimate this prevalence in Lebanese schoolchildren and to assess the relation between iron status and related factors.

SUBJECTS/METHODS

A total of 903 children aged 8-18 years (466 boys and 437 girls) were included in the study. Recruitment was done from ten schools with different SES levels and located in the Great Beirut and Mount Lebanon areas. Serum ferritin was measured in all participants and testosterone was measured only in boys using Immulite chemiluminescent assays.

RESULTS

For the entire sample, the median serum ferritin concentration was 30.0 [19.8-44.8] ng/mL and the prevalence of iron deficiency (ferritin < 15 ng/mL) was 14.2%. Iron deficiency was higher in girls compared with boys (respectively, 20.8% and 7.9%). This prevalence varied with the SES (respectively, 11.6%, 11.9%, and 16.8% in high, middle, and low SES, p = 0.09). Iron deficiency increased with age (9.5%, 15.7%, and 17.5%, respectively, for the age groups 8-11, 12-14, and 15-18, p = 0.014) and did not differ between normal, overweight, and obese groups (p = 0.07). In boys, a significant positive correlation was observed between ferritin and total testosterone (rho = 0.150, p = 0.001).

CONCLUSION

The prevalence of iron deficiency is relatively low in Lebanon. Younger boys, menstruating girls, and children from low SES are more prone to iron deficiency, while BMI has no impact.

The relationship between iron deficiency anemia and sexual function and satisfaction among reproductive-aged Iranian women

Iron deficiency anemia (IDA) is a common micronutrient deficiency worldwide, and an important health problem especially in women of reproductive age. This study aimed to determine the relationship between IDA and sexual satisfaction and function among reproductive-aged Iranian women. In this study, 129 women (52 with IDA and 77 non-IDA) with age 18–45 in Mahshahr, Iran were recruited. Data was gathered by a demographic questionnaire, Female Sexual Function Index (FSFI) and Larson Sexual Satisfaction Questionnaire. Data were analyzed using an independent t-test, Mann-Whitney test, Chi-square, and correlation coefficient test. The results of this study showed that the means of hemoglobin (Hb), hematocrit (HCT), serum iron and ferritin were significantly lower in the IDA group than those in the non-IDA group (p<0.01). All dimensions of sexual function and satisfaction were significantly lower in women with IDA compared to the healthy women (p<0.001). Also, all blood indices for IDA had a significant relationship with all sexual function components and sexual satisfaction (p = 0.01) except for pain with Hb and ferritin. Health care providers should provide screening, education, and counseling about anemia and sexual function in reproductive age women.

Testosterone-Associated Dietary Pattern Predicts Low Testosterone Levels and Hypogonadism

Obesity and low serum testosterone (T) levels are interrelated and strongly influenced by dietary factors, and their alteration entails a great risk of hypogonadism. Substantial evidence suggests a bidirectional relationship between nutrient metabolism (e.g., glucose, lipids, and iron) and T levels in men; however, T-related dietary patterns remain unclear. This study investigated the dietary patterns associated with serum total T levels and its predictive effect on hypogonadism and the body composition. Anthropometry, blood biochemistry, and food frequency questionnaires were collected for 125 adult men. Dietary patterns were derived using a reduced rank regression from 32 food groups. Overall prevalence rates of central obesity and hypogonadism were 48.0% and 15.7%, respectively. An adjusted linear regression showed that age, insulin, red blood cell (RBC) aggregation, and transferrin saturation independently predicted serum total T levels (all p < 0.01). The total T-related dietary pattern (a high consumption of bread and pastries, dairy products, and desserts, eating out, and a low intake of homemade foods, noodles, and dark green vegetables) independently predicted hypogonadism (odds ratio: 5.72; 95% confidence interval: 1.11‒29.51, p < 0.05) for those with the highest dietary pattern scores (Q4) compared to those with the lowest (Q1). Scores were also negatively correlated with the skeletal muscle mass (p for trend = 0.002) but positively correlated with the total body fat mass (p for trend = 0.002), visceral fat mass (p for trend = 0.001), and to a lesser extent, subcutaneous fat mass (p for trend = 0.035) after adjusting for age. Randomized controlled trials are needed to confirm that improvement in dietary pattern can improve T levels and reduce hypogonadism.

Serum ferritin and primary lung cancer

Existing research yields conflicting results regarding the relation between iron deficiency and high serum ferritin (SF) levels in primary lung cancer patients. We investigated the concentrations of SF, hemoglobin (Hb) and transferrin (TRF) in 569 male primary lung cancer patients and 252 female primary lung cancer patients. We grouped the subjects according to gender, smoking status, menopausal status, pathological type, stage, and TNM stage. The levels of SF and TRF were correlated with T stage in male patients (p<0.01). The levels of SF and TRF were correlated with menopausal status in female patients (p<0.01). Hb was correlated with smoking status, pathological type, stage, and TNM stages in male patients(p<0.01), but in female patients, Hb was not correlated with these grouping factors(p>0.05). The levels of SF may be regulated by different mechanisms and may be of different physiological significance in different populations.

Increased serum ferritin levels are independently associated with carotid atherosclerosis in women

Previous studies have supported the theory that there is a positive association between ferritin and carotid atherosclerosis in Western people. Diet plays an important role in determining serum ferritin concentration. Asian dietary patterns are different from Western dietary patterns, implying that there may be a difference in the association of ferritin with carotid atherosclerosis between Asian and Western people. However, few studies focus on the association between ferritin and carotid atherosclerosis among Asians. The aim of this study was to investigate how serum ferritin levels are associated with carotid atherosclerosis in an Asian adult population. A cross-sectional assessment was performed in 8302 adults in Tianjin, China. Carotid intima-media thickness (IMT) and plaques were assessed using ultrasonography, and serum ferritin was measured using the protein chip-chemiluminescence method. Multiple logistic regression analysis was used to examine the association between quartiles of serum ferritin concentration and carotid atherosclerosis. In the present study, the overall prevalence of IMT and carotid plaques in participants is 29·2 and 22·7 %, respectively. In women, after adjustments for potentially confounding factors, the OR of IMT and carotid plaques by increasing serum ferritin quartiles were 1·00, 1·39 (95 % CI 0·98-1·99), 1·39 (95 % CI 0·99-1·97), 1·81 (95 % CI 1·30-2·55) (P for trend<0·001) and 1·00, 1·24 (95 % CI 0·89-1·73), 1·18 (95 % CI 0·85-1·65), 1·59 (95 % CI 1·15-2·20) (P for trend<0·01), respectively. However, no association was found between serum ferritin and carotid atherosclerosis in men. The study demonstrated that increased serum ferritin levels are independently associated with IMT and carotid plaques in Asian women but not in Asian men.

Gender difference in relationship between serum ferritin and 25-hydroxyvitamin D in Korean adults

BACKGROUND

The present study was conducted to assess the gender difference in the relationship between serum ferritin and 25-hydroxyvitamin D [25(OH)D] in Korean adults.

METHODS

A total of 5,147 adults (2,162 men, 1,563 premenopausal women, and 1,422 postmenopausal women) aged ≥ 20 years from the Korean National Health and Nutrition Examination Survey (KNHANES) data (2012) were analyzed. A covariance test adjusted for covariates was performed for serum ferritin levels in relation to vitamin D status (vitamin D deficiency, 25(OH)D < 10.0 ng/mL; vitamin D insufficiency, 25(OH)D ≥ 10.0, < 20.0 ng/mL; vitamin D sufficiency, 25(OH)D ≥ 20.0 ng/mL).

RESULTS

The key study results were as follows: First, in men, in terms of serum ferritin levels by serum 25(OH)D level after adjusting for age, smoking, alcohol drinking, regular exercise, SBP, DBP, WM. TC, TGs, HDL-C, FPG, Hb, Hct, MCV, and Fe, serum ferritin levels were inversely increased with the increasing of serum 25(OH)D level (P = 0.012). Second, in premenopausal women, after adjusting for related variables, serum ferritin levels were increased with the increasing of serum 25(OH)D level (P = 0.003). Third, in postmenopausal women, after adjusting for related variables, serum ferritin levels were not significantly increased with the increasing of serum 25(OH)D level (P = 0.456).

CONCLUSION

Serum 25(OH)D level was inversely associated with the serum ferritin levels in men, but was positively associated with the serum ferritin levels in premenopausal women, and was not associated with the serum ferritin levels in postmenopausal women.

Serum Ferritin Is Inversely Correlated with Testosterone in Boys and Young Male Adolescents: A Cross-Sectional Study in Taiwan

Objective

The transition from childhood to teenaged years is associated with increased testosterone and a decreased iron status. It is not clear whether higher testosterone levels cause the decreased iron status, and to what extent, obesity-related inflammation influences the iron-testosterone relationship. The aim of the present study was to examine relationships of testosterone, iron status, and anti-/proinflammatory cytokines in relation to nutritional status in boys and young adolescent Taiwanese males.

Methods

In total, 137 boys aged 7~13 yr were included. Parameters for obesity, the iron status, testosterone, and inflammatory markers were evaluated.

Results

Overweight and obese (ow/obese) boys had higher mean serum testosterone, interleukin (IL)-1β, and nitric oxide (NO) levels compared to their normal-weight counterparts (all p<0.05). Mean serum ferritin was slightly higher in ow/obese boys compared to normal-weight boys, but this did not reach statistical significance. A multiple linear regression showed that serum ferritin (β = -0.7470, p = 0.003) was inversely correlated with testosterone, while serum IL-10 (β = 0.3475, p = 0.009) was positively associated with testosterone after adjusting for covariates. When normal-weight boys were separately assessed from ow/obesity boys, the association between testosterone and serum ferritin became stronger (β = -0.9628, p<0.0001), but the association between testosterone and IL-10 became non-significant (β = 0.1140, p = 0.4065) after adjusting for covariates. In ow/obese boys, only IL-10 was weakly associated with serum testosterone (β = 0.6444, p = 0.051) after adjusting for age.

Conclusions

Testosterone and serum ferritin are intrinsically interrelated but this relationship is weaker in ow/obese boys after adjusting for age.

Association between sex, systemic iron variation and probability of Parkinson's disease

OBJECTIVE

Iron homeostasis appears altered in Parkinson's disease (PD). Recent genetic studies and meta-analyses have produced heterogeneous and inconclusive results. In order to verify the possible role of iron status in PD, we have screened some of the main metal gene variants, evaluated their effects on iron systemic status, and checked for possible interactions with PD.

MATERIALS AND METHODS

In 92 PD patients and 112 healthy controls, we screened the D544E and R793H variants of the ceruloplasmin gene (CP), the P589S variant of the transferrin gene (TF), and the H63D and C282Y variants of the HFE gene, encoding for homologous proteins, respectively. Furthermore, we analyzed serum concentrations of iron, copper and their related proteins.

RESULTS

The genetic investigation revealed no significant differences in allelic and genotype distributions between patients and controls. Two different multivariable forward stepwise logistic models showed that, when the effect of sex is considered, an increase of the probability of having PD is associated with low iron concentration and Tf-saturation.

CONCLUSIONS

This study provides new evidence of the involvement of iron metabolism in PD pathogenesis and reveals a biological effect of sex.

High serum ferritin level is an independent risk factor for metabolic syndrome in a Chinese male cohort population

BACKGROUND

Elevated serum ferritin levels have been reported to contribute to metabolic syndrome (MetS). We examined the association of serum ferritin levels with the development of MetS in a representative sample of Chinese male adult population.

METHOD

The data came from the 2009-2013 Fangchenggang Area Males Health and Examination Survey (FAMHES). We combined a cross-sectional study of 2417 males and a longitudinal study of 857 males who participated in the FAMHES.

RESULT

The serum ferritin level of MetS was higher than that of nonMetS (median and percentiles 25-75: 447.4 (294.1-612.4) vs. 302.4 (215.0-435.8) ng/ml, p < 0.01). A positive correlation between ferritin concentrations and blood pressure (Systolic BP: R = 0.110, Diastolic BP: R = 0.158), waist circumference (R = 0.333), fasting glucose (R = 0.089), triglyceride (R = 0.315) and low high-density lipoprotein cholesterol (R = 0.130) was significant (all p < 0.001). Compared with the level of ferritin in the group with no MetS component, the group with all five MetS components had a higher ferritin level (554.7 (340.1-606.4) vs. 274.2 (198.2-384.4) ng/ml). The odd radio (OR) was higher for MetS in the highest ferritin quartile (OR = 2.29, 95% CI = 1.47-3.54) compared with the lowest ferritin quartile after adjustment for multi-factors. After 4-year follow up, 79 subjects newly diagnosed with MetS in 857 cohort male participants in 2013. Compared with the lowest ferritin quartile, the RR of the highest ferritin quartile was 2.55 (95% CI = 1.30-5.00) after multiple adjustments (p < 0.01).

CONCLUSION

Our findings confirm that the serum ferritin level is associated with the independent components of MetS, and elevated ferritin level is an independent risk factor for MetS development in the Chinese male population during the 4-year follow-up period.

Genome-wide association study identifies variants in PMS1 associated with serum ferritin in a Chinese population

Only a small proportion of genetic variation in serum ferritin has been explained by variant genetic studies, and genome-wide association study (GWAS) for serum ferritin has not been investigated widely in Chinese population. We aimed at exploring the novel genetic susceptibility to serum ferritin, and performed this two stage GWAS in a healthy Chinese population of 3,495 men aged 20–69 y, including 1,999 unrelated subjects in the first stage and 1,496 independent individuals in the second stage. Serum ferritin was measured with electrochemiluminescence immunoassay, and DNA samples were collected for genotyping. A total of 1,940,243 SNPs were tested by using multivariate linear regression analysis. After adjusting for population stratification, age and BMI, the rs5742933 located in the 5′UTR region of PMS1 gene on chromosome 2 was the most significantly associated with ferritin concentrations (P-combined = 2.329×10⁻¹⁰) (β = −0.11, 95% CI: −0.14, −0.07). Moreover, this marker was about 200kb away from the candidate gene SLC40A1 which is responsible for iron export. PMS1 gene was the novel genetic susceptibility to serum ferritin in Chinese males and its relation to SLC40A1 needs further study.