High serum ferritin levels increase the risk of hyperuricemia: a cross-sectional and longitudinal study

Coffee Consumption in Association with Serum Iron Levels: A Cross-sectional Study

This study determines the association between adult Saudi Arabian coffee consumption and serum iron levels. The extensive Saudi Arabian population, including both sexes - male and female, participated in this cross-sectional community-based study from 1 October 2020 to 31 June 2022. The participants were selected arbitrarily using the systematic simple random position. The current study enrolled 113 participants with a mean age of 33 years, including 94 (83.2%) females and 19 (16.8%) males. The concentration of iron absorption assessed among 62 individuals who participated in the group of occasional coffee drinkers was higher (54.9%) than the 51 individuals who participated in the group of regular coffee drinkers (45.1%). In daily coffee consumption, paired samples statistics in mean baseline WBC level (103/μl) was 6.396. On day 31 of June 2022, WBC level (103/μl) was 6.114. Paired samples statistics in mean baseline iron level was 44.29. On day 31 of June 2022, iron level was 72.15. The paired samples correlation in baseline and day 31 iron levels was 0.719, with a significant difference of 0.000. It is critical to acquire the most recent information and local statistics on the frequency of low serum iron levels in Saudi Arabia's diverse adult population. The adult population of Saudi Arabia correlates with coffee consumption and changes in serum ferritin or iron levels and WBC counts. Neither the WBC numbers nor the iron levels were significantly altered. Further research is needed to determine the potential mechanisms causing these relationships.

A cross-sectional study of the association between blood metal mixtures exposure and hyperuricemia

OBJECTIVES

To determine the association between blood metal mixture and HUA risk.

METHODS

A cross-sectional study was performed based on the populations from Kailuan cohort trial in China. Inductively coupled plasma mass spectrometry was utilized to detect the blood concentrations of iron (Fe), lead (Pb), calcium (Ca), copper (Cu), magnesium (Mg), zinc (Zn), selenium (Se), and manganese (Mn). Multivariate logistic regression (MLR) models and weighted quantile sum (WQS) regression models were employed to assess the relationships.

RESULTS

There were 3706 participants included in this study, and 464 (12.52%) were with HUA. The mean level of uric acid was 485.60 μmol/L in the subjects with HUA, which was remarkably increased compared to those without HUA (293.10 μmol/L). The multivariate-adjusted odds ratios (95% confidence intervals) of HUA were 2.15 (1.40, 3.29) for Pb, 3.42 (2.24, 5.23) for Fe, 1.61 (1.15, 2.25) for Ca, 3.06 (2.04, 4.59) for Mg, and 1.69 (1.26, 2.28) for Zn by comparing the highest and lowest metal quartiles using the single-metal logistic regression model. Meanwhile, the WQS regression models demonstrated a positive association between metal mixtures and HUA risk, to which, Fe, Mg, Pb, and Zn were the major contributors. Pb, Fe, and Zn were still robust in multiple-metal models. Age, gender, weight, smoking, and drinking status could modify these relationships with significant interactions.

CONCLUSIONS

Co-exposure to Fe, Pb, Ca, Cu, Zn, Mg, Se, and Mn were related to increased HUA risk in Chinese adults, of with, Pb, Fe, and Zn appeared to have greater impacts. These relationships were more obvious in adults aged < 60 years, or women, or overweight, or non-smoking, or drinking with significant interactions. Key Points • Increased Fe, Pb, Mg, Ca, and Zn were related to increased HUA risk in dose-response fashion among Chinese adults. • The metal mixture dominated by Fe, Mg, Pb, and Zn was positively associated with HUA risk. Fe, Pb, and Zn were still robust in MM model. • Such association was stronger showed in adults aged < 60 years, or women, or overweight, or non-smoking, or drinking with significant interactions.

Mechanistic elucidation of ferroptosis and ferritinophagy: implications for advancing our understanding of arthritis

In recent years, the emerging phenomenon of ferroptosis has garnered significant attention as a distinctive mode of programmed cell death. Distinguished by its reliance on iron and dependence on reactive oxygen species (ROS), ferroptosis has emerged as a subject of extensive investigation. Mechanistically, this intricate process involves perturbations in iron homeostasis, dampening of system Xc-activity, morphological dynamics within mitochondria, and the onset of lipid peroxidation. Additionally, the concomitant phenomenon of ferritinophagy, the autophagic degradation of ferritin, assumes a pivotal role by facilitating the liberation of iron ions from ferritin, thereby advancing the progression of ferroptosis. This discussion thoroughly examines the detailed cell structures and basic processes behind ferroptosis and ferritinophagy. Moreover, it scrutinizes the intricate web of regulators that orchestrate these processes and examines their intricate interplay within the context of joint disorders. Against the backdrop of an annual increase in cases of osteoarthritis, rheumatoid arthritis, and gout, these narrative sheds light on the intriguing crossroads of pathophysiology by dissecting the intricate interrelationships between joint diseases, ferroptosis, and ferritinophagy. The newfound insights contribute fresh perspectives and promising therapeutic avenues, potentially revolutionizing the landscape of joint disease management.

Protecting against ferroptosis in hyperuricemic nephropathy: The potential of ferrostatin-1 and its inhibitory effect on URAT1

Hyperuricemic nephropathy (HN) is characterized by renal fibrosis and tubular necrosis caused by elevated uric acid levels. Ferroptosis, an iron-dependent type of cell death, has been implicated in the pathogenesis of kidney diseases. The objective of this study was to explore the role of ferroptosis in HN and the impact of a ferroptosis inhibitor, ferrostatin-1 (Fer-1). The study combined adenine and potassium oxonate administration to establish a HN model in mice and treated HK-2 cells with uric acid to simulate HN conditions. The effects of Fer-1 on the renal function, fibrosis, and ferroptosis-associated molecules were investigated in HN mice and HK-2 cells treated with uric acid. The HN mice presented with renal dysfunction characterized by elevated tissue iron levels and diminished antioxidant capacity. There was a significant decrease in the mRNA and protein expression levels of SLC7A11, GPX4, FTL-1 and FTH-1 in HN mice. Conversely, treatment with Fer-1 reduced serum uric acid, serum creatinine, and blood urea nitrogen, while increasing uric acid levels in urine. Fer-1 administration also ameliorated renal tubule dilatation and reduced renal collagen deposition. Additionally, Fer-1 also upregulated the expression levels of SLC7A11, GPX4, FTL-1, and FTH-1, decreased malondialdehyde and iron levels, and enhanced glutathione in vivo and in vitro. Furthermore, we first found that Fer-1 exhibited a dose-dependent inhibition of URAT1, with the IC50 value of 7.37 ± 0.66 μM. Collectively, the current study demonstrated that Fer-1 effectively mitigated HN by suppressing ferroptosis, highlighting the potential of targeting ferroptosis as a therapeutic strategy for HN.

The relative and interactive effects of urinary multiple metals exposure on hyperuricemia among urban elderly in China

Objective

Independent and interactive effects of multiple metals levels in urine on the risk of hyperuricemia (HUA) in the elderly were investigated.

Methods

A total of 6,508 individuals from the baseline population of the Shenzhen aging-related disorder cohort were included in this study. We detected urinary concentrations of 24 metals using inductively coupled plasma mass spectrometry, fitted unconditional logistic regression models, and the least absolute shrinkage and selection operator regression models for the selection of metals as well as unconditional stepwise logistic regression models and restricted cubic spline logistic regression models for assessing the associations of urinary metals and HUA risk, and finally applied generalized linear models to determine the interaction with urinary metals on the risk of HUA.

Results

Unconditional stepwise logistic regression models showed the association between urinary vanadium, iron, nickel, zinc, or arsenic and HUA risk (all P < 0.05). We revealed a negative linear dose-response relationship between urinary iron levels and HUA risk (P _overall < 0.001, P _nonliner = 0.682), a positive linear dose-response relationship between urinary zinc levels and HUA risk (P _overall < 0.001, P _nonliner = 0.513), and an additive interaction relationship between urinary low-iron and high-zinc levels and HUA risk (RERI = 0.31, 95% CI: 0.03-0.59; AP = 0.18, 95%CI: 0.02-0.34; S = 1.76, 95%CI: 1.69-3.49).

Conclusion

Urinary vanadium, iron, nickel, zinc, or arsenic levels were associated with HUA risk, and the additive interaction of low-iron (<78.56 μg/L) and high-zinc (≥385.39 μg/L) levels may lead to a higher risk of HUA.

Iron Deficiency in Vegetarian and Omnivorous Individuals: Analysis of 1340 Individuals

The objective of this study was to evaluate the serum levels of ferritin and the prevalence of iron deficiency in vegan and omnivorous individuals by taking into account the presence of elements that cause an elevation of ferritin levels, such as increased homeostatic model assessment of insulin resistance (HOMA-IR), body mass index (BMI), and high-sensitivity C-reactive protein (hs-CRP) values. The parameters were evaluated in 1340 individuals, i.e., 422 men and 225 women who do not menstruate and 693 women who do menstruate, based on omnivorous or vegetarian eating habits. The progressive increase in BMI, HOMA-IR, and inflammation caused an elevation in ferritin concentration, regardless of the eating habits in the groups studied. In the overall sample, omnivores had a higher prevalence of obesity, higher ferritin levels, and a lower prevalence of iron deficiency (ferritin < 30 ng/mL). However, after the exclusion of individuals with inflammation (with overweight/obesity and elevated hs-CRP levels), the actual iron deficiency was assessed and was not higher among vegetarians, except in women with regular menstrual cycles. Our data show that nutritional status and inflammation levels affect ferritin levels and may interfere with the correct diagnosis of iron deficiency in both vegetarian and omnivorous individuals. Compared to vegetarians, women who do not menstruate and men had the same prevalence of iron deficiency when following an omnivorous diet.

Effect of Serum Ferritin on the Association Between Coffee Intake and Hyperuricemia Among American Women: The National Health and Nutrition Examination Survey

Background

Accruing evidence suggests an inverse relationship between coffee intake and serum uric acid. The mechanism(s) explaining this inverse relationship remains elusive. The aim of this study was to assess if the association between coffee intake and hyperuricemia is mediated via serum ferritin in women.

Methods

We pooled data from the 2003 to 2006 National Health and Nutrition Examination Survey (NHANES). We included women with complete information on all key variables. Coffee intake was classified as none, <1 cup/day, 1-3 cups/day, and ≥4 cups/day. Hyperuricemia was defined as serum uric acid >5.7 mg/dL. We assessed the association between coffee intake and hyperuricemia using logistic regression. Path analysis was used to examine whether serum ferritin mediated the effect of coffee on hyperuricemia.

Results

Among 2,139 women (mean age: 31.2 years [SD: 9.2]), mean serum uric acid was 4.4 mg/dL (SD: 1.0), and 227 (10.6%) had hyperuricemia. In multivariate logistic regression models, intake of ≥4 cups/day of coffee was associated with lower odds of hyperuricemia (OR 0.28 [95% CI: 0.09, 091], P=0.035). The total direct and indirect effect of coffee on hyperuricemia via serum ferritin was −0.16, P=0.009 and −8.1 × 10⁻³, P=0.204, respectively.

Conclusion

Among women, moderate coffee consumption was inversely related to hyperuricemia by direct effect, rather than indirectly through the effects of serum ferritin. These findings suggest that serum ferritin does not mediate the inverse association between coffee and hyperuricemia in women.

Economic Status Moderates the Association Between Early-Life Famine Exposure and Hyperuricemia in Adulthood

CONTEXT

The double burden of malnutrition (DBM), undernutrition in early life and an obesogenic environment later on, influences later risk of chronic disorders. The Great Famine in China from 1959 to1962 and remarkable economic development from the 1980s provided such a burden for a large number of people in their 60s.

OBJECTIVE

We aimed to analyze the effect of economic status on the association between famine exposure in early life and hyperuricemia in adulthood.

DESIGN AND SETTING

Participants numbering 12 666 were enrolled in China based on the Survey on Prevalence in East China for Metabolic Diseases and Risk Factors (SPECT-China) Study from 2014 to 2016.

PARTICIPANTS

Participants with fetal or childhood famine exposure (birth year 1949-1962) formed the exposure group.

MAIN OUTCOME MEASURE

Hyperuricemia was defined as uric acid (UA) > 420 μmol/L for men and > 360 μmol/L for women. The association of famine with hyperuricemia was assessed via regression analyses.

RESULTS

Early-life famine exposure was negatively associated with UA levels (P = .045) but was not associated with hyperuricemia (P = .226) in the whole study population. Economic status could moderate the association of famine exposure with UA and hyperuricemia (P ≤ .001). In participants with high economic status, early-life famine exposure was positively associated with UA levels (unstandardized coefficients 7.61, 95% CI 3.63-11.59, P < .001), and with hyperuricemia (odds ratio 1.47, 95% CI 1.19-1.81, P < .001).

CONCLUSIONS

Economic status could moderate the association between exposure to famine in early life and hyperuricemia in adulthood, indicating that the DBM might affect hyperuricemia in an opposite direction of the effects of undernutrition in early life alone.

Associations of serum iron and ferritin with hyperuricemia and serum uric acid

OBJECTIVES

To assess the serum iron and ferritin levels in relation to the prevalence of hyperuricemia (HU) and the serum uric acid (SUA) level.

METHODS

Serum iron and ferritin concentrations were detected by Ferene method and chemiluminescence method, respectively. SUA level was detected by uricase-PAP method. HU was defined as SUA ≥ 416 μmol/L for male and ≥ 357 μmol/L for female. Multivariable-adjusted logistic regressions were constructed to investigate the associations between serum iron/ferritin levels and prevalence of HU. Pearson correlation analysis and multivariable linear regression were performed to examine the correlations between serum iron/ferritin levels and SUA level.

RESULTS

A total of 2824 subjects (mean age 52.2 ± 7.2) were included. The overall prevalence of HU was 17.3%. Compared with the lowest quartile, the multivariable-adjusted odds ratios (OR) and its 95% confidence interval (CI) of HU were 1.33 (95%CI 0.97-1.82), 1.17 (95%CI 0.85-1.60), and 1.56 (95%CI 1.14-2.13) in the second, third, and fourth quartiles of serum iron, respectively (P for trend = 0.012), and were 1.29 (95%CI 0.89-1.88) in the second, 2.13 (95%CI 1.47-3.07) in the third, and 2.25 (95%CI 1.54-3.29) in the fourth quartile of serum ferritin (P for trend < 0.001). Pearson correlation coefficient indicated a weak positive correlation between serum iron (r = 0.2, P < 0.001) and ferritin (r = 0.3, P < 0.001) levels and SUA. Such positive correlations were further confirmed by multiple linear regression (serum iron: standardized β = 0.059, P < 0.001; serum ferritin: standardized β = 0.061, P = 0.001).

CONCLUSIONS

Both serum iron and ferritin showed a positive correlation with the prevalence of HU, and a weak positive correlation with SUA level. Key Points • Subjects with higher levels of serum iron or ferritin had higher prevalence of HU. • There was a weak positive correlation between serum iron/ferritin levels and SUA level.

Causal associations of iron status with gout and rheumatoid arthritis, but not with inflammatory bowel disease

BACKGROUND & AIMS

We conducted a two-sample Mendelian randomization study to assess the associations of iron homeostasis with the risk of gout, rheumatoid arthritis and inflammatory bowel disease.

METHODS

Single-nucleotide polymorphisms for iron status were selected at the genome-wide significance level from a large genome-wide association study of 48 972 European-descent individuals. Summary-level data for gout, rheumatoid arthritis and inflammatory bowel disease were obtained from The Global Urate Genetics Consortium and two large genome-wide association studies, respectively. Inverse-variance weighted method with random-effects and sensitivity analyses were performed.

RESULTS

Genetic predisposition to high iron status was causally associated with higher odds of gout, lower odds of rheumatoid arthritis, but not associated with inflammatory bowel disease. The odds ratios of gout were 1.35 (95% confidence interval (CI), 1.00, 1.81; p = 0.047), 2.07 (95% CI, 1.23, 3.50; p = 0.006), 1.27 (95% CI, 1.07, 1.50; p = 0.007) and 0.69 (95% CI, 0.54, 0.90; p = 0.005) per one standard deviation increment of serum iron, ferritin, transferrin saturation, and transferrin levels, respectively. For rheumatoid arthritis, the corresponding odds ratios were 0.79 (95% CI, 0.65, 0.94; p = 0.010), 0.59 (95% CI, 0.40, 0.86; p = 0.007), 0.84 (95% CI, 0.75, 0.94; p = 0.003) and 1.28 (95% CI, 1.06, 1.55; p = 0.012).

CONCLUSIONS

Based on consistent findings for four iron biomarkers, genetically high iron status was positively associated with gout and inversely associated with rheumatoid arthritis. There was limited MR evidence supporting a causal association between iron status and inflammatory bowel disease.

Association between Eating Away from Home and Hyperuricemia: A Population-Based Nationwide Cross-Sectional Study in China

Hyperuricemia (HU) is a risk factor for different kinds of chronic noncommunicable diseases, and eating away from home (EAFH) may play an important role in their development, which has been ignored greatly so far. This study aimed to investigate the association between EAFH and HU in different models. A cross-sectional study involving 8,322 participants of the China Health and Nutrition Survey (CHNS) was conducted. Logistic regression models were used to analyze the data. We found that participants who consumed more away-from-home food had a higher risk for HU, and the adjusted odds ratio (aOR) and 95% confidence interval (CI) (for each increment in grades of EAFH) were 1.11 (1.02, 1.20) in a multiadjusted model (adjusted for age, gender, province, net individual income, body mass index, smoking, leisure-time physical activities, energy intake, and sleep duration). As for stratified analyses, the aOR (95% CI) of EAFH was 1.12 (1.01, 1.24) for men and 1.06 (0.92, 1.21) for women. Similar results can be found in the middle-aged and obese population, with aOR (95% CI) of EAFH as 1.17 (1.05, 1.30) and 1.15 (1.03, 1.29), respectively. In conclusion, EAFH is positively associated with the prevalence of HU.

Risk factors for the development of hyperuricemia: A STROBE-compliant cross-sectional and longitudinal study

Hyperuricemia has received increasing attention as a major public health problem. This study aims to investigate the risk factors for hyperuricemia and to explore the relationship between changes in biochemical variables and incident hyperuricemia.A cross-sectional and subsequently prospective study was performed among adults who took their health checkups at Zhejiang University Hospital. The participants who were free of hyperuricemia at baseline received annual follow-up examinations during a 6-year period. Cox proportional hazards regression analyses were conducted to calculate the risks for incident hyperuricemia.Of the 9238 participants enrolled, 1704 (18.4%) were diagnosed as hyperuricemia. During 21,757 person-years of follow-up, 1492 incident hyperuricemia cases were identified. The incidence of hyperuricemia was 68.58 cases per 1000 person-year of follow-up in the overall participants. The prevalence and the incidence of hyperuricemia increased greatly in female older than 50 years. High levels of BMI, SBP, FPG, TG, LDL-C, ALT, BUN, and creatinine increased the risk of hyperuricemia. Suffering fatty liver also increased the risk of hyperuricemia. Subjects with increasing DBP, TG, BUN, creatinine, or decreasing HDL-C were more likely to incident hyperuricemia.This study revealed that the change of diastolic blood pressure (DBP), serum triglycerides (TG), blood urea nitrogen (BUN), creatinine, and high-density lipoprotein cholesterol (HDL-C) level were independently associated with incident hyperuricemia.

Markers of Iron Status Are Associated with Risk of Hyperuricemia among Chinese Adults: Nationwide Population-Based Study

Background: Elevated serum uric acid (SUA) involved in iron metabolism, has been increasingly recognized as a risk factor for gout and cardiovascular diseases. The objective of this study was to examine the associations between markers of iron status with risk of hyperuricemia (HU) in Chinese adult population. Methods: Data were extracted from the 2009 wave of the China Health and Nutrition Survey, consisting of 7946 apparently healthy adults. Serum ferritin (SF), transferrin, soluble transferrin receptors (sTfR), hemoglobin (Hb), high-sensitivity C-reactive protein (hs-CRP), and SUA were measured. Diet was assessed with three consecutive 24 h recalls. Demographic characteristics, smoking status, alcohol consumption, and physical activities were investigated using a structured questionnaire. Multilevel mixed-effects models were constructed to estimate the associations of SF, transferrin, sTfR, and Hb with SUA and the risk of HU. Results: The crude prevalence of HU was 16.1%. SF, transferrin, and Hb levels were positively associated with SUA and the risk of HU after adjustment for cluster effects and potential confounders (all p-trend < 0.05). Compared with participants in the lowest quartile of SF, those in the highest quartile had significantly higher SUA concentrations (β = 0.899 mg/dL, 95% confidence interval (CI): 0.788, 1.010; p < 0.001) and higher risk of HU (odds ratio (OR) = 3.086, 95% CI: 2.450, 3.888; p < 0.001). Participants with the highest quartile of transferrin had significantly higher SUA concentrations (β = 0.488 mg/dL, 95% CI: 0.389, 0.587; p < 0.001) and higher risk of HU (OR: 1.900; 95% CI: 1.579, 2.286; p < 0.001) when compared with those with the lowest quartile. In male participants, those in the highest quartile of Hb had significantly higher risk of HU when compared to the reference group (OR: 1.401, 95% CI: 1.104, 1.777; p < 0.01); however, this association was not found in female participants (OR: 1.093; 95% CI: 0.821, 1.455; p = 0.544). Conclusion: SF, transferrin, and Hb levels were positively associated with the risk of HU, and additional studies are needed to confirm the findings, as well as to elucidate their underlying mechanisms.

Hyperferritinemia increases the risk of hyperuricemia in HFE-hereditary hemochromatosis

OBJECTIVES

Hyperuricemia is becoming increasingly frequent in the population, and is known to be sometimes the cause of gout. The impact of uric acid is still not clearly understood, however. The iron metabolism may interact with the uric acid metabolism. The aim of this study was to examine the relationship between the serum uric acid and serum ferritin levels in a cohort of hemochromatosis patients who were homozygous for the HFE p.Cys282Tyr mutation.

METHODS

738 patients with the HFE gene mutation Cys282Tyr in the homozygous state were included in the study. The variables measured during the initial evaluation were compared in univariate analysis by Student's t test. In multivariate analysis, linear stepwise regression was used.

RESULTS

In the group of hyperuricemic patients, ferritinemia was significantly higher than in the group of non-hyperuricemic patients (1576.7±1387.4μg/l vs. 1095.63±1319.24μg/l, P<0.005). With multivariate analysis, only ferritin and BMI independently explained the uricemia (R²=0.258) after adjustment for age, glycemia and CRP. The correlation between uricemia and log(ferritin) with partial regression correlation coefficients was 0.307 (P<0.01).

CONCLUSIONS

The increase in uricemia is associated with the increase in ferritin in a population of patients who were homozygous for the HFE gene mutation p.Cys282Tyr and this independently of factors commonly associated with hyperuricemia. The increase in uric acid associated with hyperferritinemia, could be a response to the visceral toxicity of excess non-transferrin bound iron linked to oxidative stress via the antioxidant properties of uric acid.