Serum Zinc Concentrations by Inflammation Status, Time of Day, and Fasting Status for Estimating Zinc Deficiency in 6-59-Mo-Old Children: Results from the Brazilian National Survey on Child Nutrition (ENANI-2019).

BACKGROUND: Serum zinc concentration (SZC) is considered the best biomarker of zinc status in population-level evaluations. However, zinc deficiency (ZD) estimations can be biased if they do not consider blood collection timing, inflammation, and fasting status. OBJECTIVES: The objectives of this study were to determine SZC without and with adjustment for inflammation, according to blood collection timing and fasting status, estimate ZD prevalence, and evaluate the associated factors with ZD in a representative sample of Brazilian children aged <5 y. METHODS: Population-based study with 7597 children aged 6-59 mo surveyed by the Brazilian National Survey on Child Nutrition. SZC was adjusted for inflammation using the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia regression correction approach, with high-sensitive C-reactive protein, assessed according to blood collection timing (morning/afternoon) and fasting status (<8 and ≥8 h). SZC <65 µg/dL (morning collection) or SZC <57 µg/dL (afternoon collection) were classified as ZD. The analysis between associated factors and ZD used the adjusted prevalence ratio (PR). RESULTS: After adjusting for inflammation, SZC was higher in all percentiles and varied according to collection timing and fasting status. Children who had blood collected in the morning without fasting or in the afternoon had lower SZC than those assessed in the morning with fasting. The differences in adjusted SZC according to the timing of collection and fasting status were greater in the higher percentiles of the distribution, with the greatest absolute difference observed when comparing the 95th percentile of morning fasting compared with nonfasting (20.3 µg/dL). The prevalence of ZD estimated without and with adjusting SZC for inflammation was 17.8% and 13.8%, respectively. The occurrence of diarrhea, fever, or respiratory symptoms in the 15 d before blood collection was associated with a higher prevalence of ZD (PR: 1.42; 95% confidence interval: 1.04, 1.94). CONCLUSIONS: Adjusting SZC for inflammation and considering fasting status is important to avoid overestimating the prevalence of ZD.

Serum zinc levels in hemodialysis and peritoneal dialysis patients: A retrospective observational study.

Background: Zinc is vital for cellular functions, but kidney failure increases zinc deficiency risk. We compared zinc levels in hemodialysis (HD) and peritoneal dialysis (PD) patients in Isfahan, Iran. Materials and Methods: A retrospective study included 150 patients (75 PD and 75 HD). Serum zinc levels were assessed through photometry. Statistical analysis employed Chi-square, independent t-test, and correlation. Results: Serum zinc was below normal in both groups (P < 0.01). HD patients had lower zinc levels (70.85 ± 7.68 mg/dL) compared to PD (75.04 ± 13.55 mg/dL, P = 0.021), remaining significant after adjusting for confounders (P = 0.011). Conclusion: Zinc levels in PD and HD patients are lower than in the general population, with HD patients having lower levels than PD patients.

Association of serum zinc levels and symptom control of asthma in children and adolescents- a prospective observational study.

Dysregulation of zinc (Zn) homeostasis causes a shift in the Th1/Th2 balance towards a Th2 response, which may lead to a heightened inflammatory response. Asthma is associated with an exaggerated Th2 response to antigens. This study attempts to find the association of serum Zn with the status of symptom control of asthma in children and adolescents with bronchial asthma. A total of 67 asthmatic children, diagnosed as per Global Initiative for Asthma (GINA) 2019 guidelines, were included in the study. Symptom control of asthma was assessed by Asthma Control Test (ACT) and Childhood Asthma Control Test (C-ACT) scores. Spirometry was performed on those participants who were able to perform satisfactorily. Serum Zn was analyzed using the photometric method. Participants were divided into two groups: controlled and uncontrolled groups according to ACT/C-ACT score. Mean age of the participants was 10.78 ± 3.67 years. The mean S. Zn (µg/dL) was 136.97 ± 48.37. This study found a higher mean S. Zn value in the controlled asthma group as compared to the uncontrolled group (158.06 vs 129.23, p = 0.006). At a cutoff of S. Zn (µg/dL) ≥ 126.84, it predicted controlled asthma with a sensitivity of 89% and a specificity of 55%. No significant difference was found between the mean serum Zn levels in terms of age, sex, severity, and CRP levels. CONCLUSION: A significant difference was observed between the mean value of Zn and symptom control of asthma (p = 0.006) with a weak positive correlation between the two which was statistically significant (rho = 0.26, p = 0.031). However, low levels of zinc were not significantly associated with symptom control of asthma. Thus, we conclude that maintaining an adequate zinc level could help in achieving better control of asthma in pediatric populations. WHAT IS KNOWN: • Zinc has a role in immunological response in the pathophysiology of immunological disorders such as bronchial asthma. WHAT IS NEW: • This study adds a significant association of serum zinc levels with symptom control of asthma in pediatric populations. • This study also gives a cut-off value of serum zinc level which predicts adequate symptom control of asthma.

Serum Copper-to-Zinc Ratio and Risk of Chronic Obstructive Pulmonary Disease: A Cohort Study.

PURPOSE: Serum copper (Cu), zinc (Zn), and Cu/Zn-ratio have emerged as ageing-related biomarkers. We sought to assess the association between Cu/Zn-ratio and chronic obstructive pulmonary disease (COPD) risk. METHODS: Serum Cu and Zn were measured using atomic absorption spectrometry in 2,503 men aged 42-61 years. RESULTS: During a median follow-up of 27.1 years, 210 COPD cases occurred. Serum Cu/Zn-ratio and Cu concentrations were linearly associated with COPD risk, whereas the relationship was curvilinear for Zn and COPD risk. A unit increase in Cu/Zn-ratio was associated with an increased COPD risk in multivariable analysis (hazard ratio, HR 1.81; 95% CI 1.08-3.05). The corresponding adjusted HR (95% CI) was 3.17 (1.40-7.15) for Cu. Compared to the bottom tertile of Zn, the HRs (95% CIs) were 0.68 (0.48-0.97) and 1.01 (0.73-1.41) for the middle and top tertiles of Zn, respectively. CONCLUSIONS: Increased serum Cu/Zn-ratio and Cu concentrations were linearly associated with an increased COPD risk in men.

Low serum zinc concentration is associated with low serum testosterone but not erectile function.

OBJECTIVE: To investigate the relation between serum zinc concentration and several factors, including serum testosterone concentration and the score of questionnaires on sexual function in patients with sexual problems. METHODS: This study comprised 720 men (age, 46.3 [21-83] years) with some kind of sexual problem. Age, scores of the Sexual Health Inventory for Men and the Erection Hardness Score, and endocrinologic data including serum concentrations of testosterone, prostate-specific antigen, and zinc were included in this study. After serum zinc concentration of the men was classified into 5 groups (<70, 70≤ <80, 80≤ <90, 90≤ <100, ≤100 µg/dl), the relation of each parameter with serum zinc concentration was assessed for a trend analysis. Finally, the relation between serum concentrations of zinc and testosterone as well sexual function evaluated by the scores of the questionnaires was investigated. RESULTS: Only serum testosterone concentration (ptrend = 0.028) and serum cortisol concentration (ptrend = 0.003) showed a statistically significant relation to serum zinc concentration by trend analysis. Interestingly, trend analysis between serum concentrations of testosterone and zinc still showed a significant association after adjustment for serum cortisol concentration (ptrend = 0.032). However, no significant association was found in the relation between serum zinc concentration and the scores of the questionnaires after adjustment for serum concentrations of testosterone and cortisol. CONCLUSION: We clearly showed that after adjustment for serum cortisol concentration by trend analysis, serum testosterone concentration decreased as serum zinc concentration decreased, although sexual symptoms were not associated with this decrease.

No evidence of a prospective relationship between serum zinc and venous thromboembolism in Caucasian men: a cohort study.

Serum zinc has been implicated as an important mediator of haemostasis and thrombosis. However, the nature and magnitude of any potential relationship between serum zinc and venous thromboembolism (VTE) is unknown. We aimed to evaluate the prospective association between serum zinc and VTE risk. We analyzed data involving 2472 men aged 42-61 years without a history of VTE in the Kuopio Ischemic Heart Disease population-based cohort study, with the assessment of serum zinc concentrations using atomic absorption spectrometry. Hazard ratios (95% confidence intervals [CIs]) for incident VTE were estimated. A total of 166 VTE cases occurred during a median follow-up of 27.1 years. The risk of VTE per 1 standard deviation increase in serum zinc in analysis adjusted for systolic blood pressure, body mass index, total cholesterol, triglycerides, smoking status, histories of type 2 diabetes and coronary heart disease, medication for dyslipidaemia, alcohol consumption, physical activity, and socioeconomic status was (HR 1.03; 95% CI 0.86-1.22), which remained similar (HR 1.04; 95% CI 0.87-1.23) following further adjustment for inflammation and history of cancer. Comparing the extreme tertiles of serum zinc, the corresponding adjusted HRs (95% CIs) were 0.92 (0.63-1.36) and 0.94 (0.64-1.39), respectively. Imputed results based on 2682 participants and 176 VTE events were consistent with the observed results. In middle-aged and older Finnish men, serum zinc is not associated with future VTE risk. Other large-scale prospective studies conducted in other populations are needed to confirm or refute these findings.

Serum copper-to-zinc ratio and risk of incident pneumonia in caucasian men: a prospective cohort study.

Serum copper (Cu) and zinc (Zn), essential micronutrients that have important immunomodulatory and antimicrobial properties, are biomarkers of ageing. Serum Cu/Zn-ratio may be a more reliable marker for age-related degenerative conditions compared with serum Cu or Zn alone. We aimed to assess the association between Cu/Zn-ratio and the risk of incident pneumonia in a prospective cohort study. Serum levels of Cu and Zn were measured at baseline using atomic absorption spectrometry in 2503 men aged 42-61 years in the Kuopio Ischemic Heart Disease prospective cohort study. Hazard ratios (HRs) with confidence intervals (CIs) were calculated for incident pneumonia using Cox regression models. A total of 599 cases of pneumonia occurred during a median follow-up of 26.1 years. Serum Cu/Zn-ratio and Cu were each linearly associated with incident pneumonia. A unit increase in Cu/Zn-ratio was associated with an increased risk of pneumonia in analysis adjusted for potential confounders including C-reactive protein (HR 1.65; 95% CI 1.17-2.33). The corresponding adjusted HR (95% CI) was 2.04 (1.22-3.40) for serum Cu. The association between serum Zn and pneumonia was curvilinear. Compared to the bottom tertile of Zn, the multivariable adjusted HRs (95% CIs) for incident pneumonia were 0.68 (0.55-0.83) and 0.96 (0.79-1.16) for the middle and top tertiles of Zn, respectively. Further analysis in the same participants showed that Cu/Zn-ratio might be a stronger risk indicator for pneumonia than serum C-reactive protein. In middle-aged and older Finnish men, increased serum Cu/Zn-ratio and Cu concentrations are each linearly associated with an increased risk of incident pneumonia.

J-shaped relationship between serum zinc levels and the severity of hepatic necro-inflammation in patients with MAFLD.

BACKGROUND AND AIMS: Zinc is an essential trace element that plays an important role in maintaining health, and affecting gene expression, signal transduction and regulation of apoptosis. It is uncertain whether serum zinc levels are altered in patients with metabolic dysfunction-associated fatty liver disease (MAFLD). We aimed to investigate the association between serum zinc levels and the severity of hepatic necro-inflammation (HN) in patients with MAFLD. METHODS AND RESULTS: Liver disease severity was graded histologically using the NAFLD activity score. HN was defined as the sum of ballooning and lobular inflammation. We used a smooth function regression model to analyze the relationship between serum zinc levels and HN. A total of 561 (76.5% men) patients with biopsy-confirmed MAFLD were enrolled. They had a mean age of 41.3 years, and a mean serum zinc level of 17.0 ± 4.1 µmol/L. Compared to those with mild hepatic necro-inflammation (MHN, grades 0-2; n = 286), patients with severe hepatic necro-inflammation (SHN, grades 3-5; n = 275) had lower serum zinc concentrations (16.3 ± 4.2 vs. 17.6 ± 4.0 µmol/L; p < 0.001). However, a threshold saturation effect analysis showed that there was an inflection in serum zinc levels at 24 µmol/L. After adjustment for potential confounders, serum zinc levels <24 µmol/L were inversely associated with SHN (adjusted-odds ratio 0.88, 95%CI 0.83-0.93; p < 0.001), whereas serum zinc levels >24 µmol/L were positively associated with SHN (adjusted-odds ratio 1.42, 95%CI: 1.03-1.97; p = 0.035). CONCLUSIONS: There is a J-shaped relationship between serum zinc levels and the severity of hepatic necro-inflammation in patients with biopsy-proven MAFLD.

Assessment of zinc inadequacy among tribal adolescent population of central India - A cross-sectional study.

Background & objectives: Zinc is a crucial micronutrient in adolescence, required for promoting growth and sexual maturation. Adolescents of some tribes may be at high risk of zinc deficiency due to dietary inadequacy and poor bioavailability of zinc from plant-based diets. This study aimed to evaluate the risk of zinc deficiency by estimating prevalence of inadequate zinc intake, prevalence of low serum zinc and stunting among tribal adolescents. Methods: A cross-sectional community-based survey was conducted among adolescents (10-19 yr) in three purposively selected districts where Bhil, Korku and Gond tribes were in majority. Structured data collection instrument comprising information about sociodemographic characteristics and dietary recall data was used. Anthropometric assessment was conducted by standardized weighing scales and anthropometry tapes, and blood sample was collected from antecubital vein into trace element-free vacutainers. Serum zinc was estimated using an atomic absorption spectrophotometer. Results: A total of 2310 households were approached for participation in the study, of which 2224 households having 5151 adolescents participated. Out of these enlisted adolescents, 4673 responded to dietary recall (90.7% response rate). Anthropometry of 2437 participants was carried out, and serum zinc was analyzed in 844 adolescents. The overall prevalence of dietary zinc inadequacy was 42.6 per cent [95% confidence interval (CI) 41.2 to 44.1] with reference to the estimated average requirement suggested by International Zinc Nutrition Consultative Group (IZiNCG) and 64.8 per cent (95% CI 63.4 to 66.2) with Indian Council of Medical Research-recommended requirements. Stunting was observed in 29 per cent (95% CI 27.2 to 30.8) participants. According to IZiNCG cut-offs, low serum zinc was detected in 57.5 per cent (95% CI 54.1 to 60.8) of adolescents, whereas it was 34.4 per cent (95% CI: 31.2-37.5) according to the national level cut-off. Interpretation & conclusions: Risk of dietary zinc inadequacy and low serum zinc concentration amongst adolescents of the Gond, Bhil and Korku tribes is a public health concern.

Association of Serum Zinc Level with severity of chronic kidney disease in diabetic patients: a cross-sectional study.

BACKGROUND: In recent years, it has been reported that diabetic patients tend to have a lower zinc intake due to unbalanced diet accompanying changes in lifestyle habits. We investigated serum zinc concentration in diabetic patients according to the stage of nephropathy. METHODS: We enrolled 227 diabetic patients (119 men, 108 women, average age 65.7 ± 14.7 [mean ± standard deviation]) who were hospitalized for diabetes treatment due to poor blood glucose control. We investigated the relationship between fasting serum zinc concentration and estimated glomerular filtration rate (eGFR) and albuminuria (urinary albumin-to-creatinine ratio, UACR), as well as serum zinc concentration by stage of diabetic kidney disease and chronic kidney disease. RESULTS: The mean HbA1c value was 10.5 ± 2.1%. Serum zinc concentration was 75.5 ± 16.0 µg/dL in males and 75.7 ± 12.2 µg/dL in females, showing no gender difference and no significant relationship with diabetes type. The serum zinc concentration was negatively correlated with age (r = - 0.309, P < 0.001) and positively correlated with eGFR (r = 0.144, P = 0.030). A tendency was observed of serum zinc concentration to decrease after overt nephropathy, with values of 76.4 ± 14.1 µg/dL in pre-nephropathy (stage 1, n = 131), 78.5 ± 13.2 µg/dL in incipient nephropathy (stage 2, n = 65), 66.4 ± 14.3 µg/dL in overt nephropathy (stage 3, n = 25), and 65.7 ± 11.9 µg/dL in kidney failure (stage 4, n = 6). Serum zinc showed a negative trend with estimated GFR (P = 0.004) and significant reduction in albuminuria, with stage A3 (n = 29, 65.7 ± 13.9 µg/dL) having lower levels than A1 (n = 131, 76.4 ± 14.1 µg/dL, P = 0.001) and A2 (n = 67, 78.4 ± 13.1 µg/dL, P < 0.001). CONCLUSIONS: In diabetic patients, serum zinc concentration tended to decrease as age increased and also as renal function deteriorated. This study suggests that consideration of zinc deficiency is necessary in patients with overt albuminuria.

Umbilical cord serum zinc in neonates delivered at the university of Nigeria teaching hospital, Enugu: Variation with gestational age.

Background: Zinc is particularly involved in cellular growth, neurodevelopment, and immune function, which is critical for child survival. To reduce neonatal mortality in developing countries, cost-effective and evidence-based interventions that can enhance growth, development, and immunity, need to be considered. Determining the zinc levels of neonates and how it relates to both gestational age is therefore imperative. Subjects and Methods: A descriptive cross-sectional study was carried out at the University of Nigeria Teaching Hospital, aimed at determining the umbilical cord serum zinc levels among neonates and their relationship with their gestational age. Two hundred and seventy-five neonates of gestational ages 28 to 42 weeks were enrolled in the study. Serum zinc levels were determined using the flame atomic absorption spectrophotometer (AAS model no. FS 240 AA.USA, Agilent Technology Ltd.). Results: Among the 275 neonates, there were 27 (9.82%), 28 (10.18%), and 220 (80%) preterms, moderate-to-late preterms, and term neonates, respectively. The mean serum zinc level of all neonates was 87 ± 16.07 µg/dL and within the normal limit of serum zinc. Their mean serum zinc level increased with increasing gestational age (F = 90.424, P < 0.001). Very preterm and moderate-to-late preterm neonates had mean serum zinc levels of 65.13 µg/dL ± 6.15 and 69.85 µg/dL ± 9.63 µg/dL, respectively. Conclusion: This study revealed that though the overall mean serum zinc of neonates was normal, preterms (especially those of lower gestational ages) were zinc deficient. Routine zinc supplementation at birth should be considered in preterm neonates to reduce the untoward effects of zinc deficiency.

Serum zinc deficiency in patients after gastrectomy for gastric cancer.

PURPOSE: Zinc is an essential dietary component for humans and the second most prevalent trace element; however, serum zinc levels after gastrectomy have not been fully elucidated. This study aimed to evaluate the correlation between clinicopathologic features and serum zinc levels in patients who underwent gastrectomy for gastric cancer. METHODS: The study enrolled 617 patients who underwent gastrectomy for gastric cancer at the Kochi Medical School. Clinical data were obtained to investigate associations between clinicopathological features, including nutritional indicators and serum zinc levels. Serum zinc deficiency was defined as serum zinc level < 80 µg/dL. RESULTS: The median zinc level of the 617 patients was 73 µg/dL (range, 31-144 µg/dL), and serum zinc deficiency was present in 68.6% of patients. Median age was significantly higher in the zinc low level group than in the normal group (69 vs. 66 years, P < 0.001). Albumin was significantly lower in the zinc low level group than in the normal group (3.9 vs. 4.2 g/dL, P < 0.001). C-reactive protein level was significantly higher in the zinc low level group than in the normal group (0.12 vs. 0.10 mg/dL, P = 0.014). The median serum zinc level was significantly lower in the patients who received chemotherapy after gastrectomy than in those who were not received chemotherapy (72 vs. 76 µg/dL, P < 0.001). Serum zinc levels showed a significant positive correlation with serum albumin (r = 0.505, P = 0.044). Multivariate analysis showed that serum albumin level was significantly associated with serum zinc level (ß = 0.489, P < 0.001). CONCLUSIONS: Serum zinc deficiency was found in 68.6% of postoperative patients who underwent gastrectomy for gastric cancer, which was highly correlated with serum albumin.

Relationship between serum zinc concentration and semen quality in newly-wed men.

OBJECTIVES: To clarify factors associated with semen quality and confirm whether there is an association between semen quality and serum zinc concentration. METHODS: A semen test was performed on 217 men just after or just before marriage. Variables assessed in the study were: age; symptomatic scores, including sexual function evaluated using several specific questionnaires; endocrinological profiles, especially follicle-stimulating hormone; and serum zinc concentrations. Based on World Health Organization criteria for assessing sperm quality, semen volume ≥1.5 mL, sperm concentration ≥15 million/mL, or sperm motility rate ≥40%, the men were grouped according to whether they had values below or above these criteria. The two groups were compared with regard to the study variables, and correlation between serum zinc concentration and semen quality was evaluated. Independent predictors for inclusion in the group with values below the criteria were investigated further. RESULTS: Of the 217 men included in the study, 45 (20.7%) were categorized as having values below the World Health Organization criteria. The men in this group were significantly older and had significantly worse sexual function, significantly higher follicle-stimulating hormone levels, and significantly lower serum zinc concentrations, than those in the group with values above the criteria. There was no significant correlation between serum zinc concentration and semen quality. However, the independent predictors for having values below the criteria in binomial logistic regression analysis were follicle-stimulating hormone and serum zinc concentration. CONCLUSION: We suggest that semen analysis may be considered in men with a low level of serum zinc and high level of follicle-stimulating hormone when developing a life plan for fertilization.

[Zinc status of 18-60 year-old adults in China in 2015].

OBJECTIVE: To estimate the distribution of serum zinc levels, zinc deficiency status and possible influencing factors in 18-60 year-old adults in China. METHODS: Based on the data of China Adult Chronic Disease and Nutrition Surveillance, 3903 blood samples were selected by stratified random sampling. The distribution of serum zinc in adults with different gender, age, regional type and regional distribution were analyzed by inductively coupled plasma mass spectrometry and body mass index(BMI), exercise, smoking, drinking, vitamin A level and other factors on serum zinc concentration and zinc deficiency rate. Multivariate logistic regression model was used to analyze the correlation between zinc deficiency and the influencing factors. RESULTS: In 2015, the median of serum zinc in Chinese adults aged 18-60 years was 103. 44(95%CI 64. 84-186. 12) µg/dL, and the overall zinc deficiency rate was 6. 04%. Serum zinc concentration had statistically significant difference(P<0. 05) in different genders, regional types, regional distribution, vitamin A status, smoking status, drinking status. In the comparison of zinc deficiency rates, ethnic minorities(10. 67 %) was higher than Han(5. 44%), rural area(7. 35%) was higher than urban area(4. 90%), vitamin A deficiency group(9. 12%) was higher than vitamin A normal group(5. 90%), non-exercise group(6. 29%) was higher than sports group(5. 09%). Among different regional distributions, the western region had the highest zinc deficiency rate(7. 33%), and among different BMI groups overweight group had the lowest rate(4. 81%). These differences were statistically significant(P<0. 05). In the analysis of multivariate logistic regression, the risk of zinc deficiency in the vitamin A deficiency group was 1. 89 higher than that of the normal group(OR=1. 89, 95%CI 1. 13-3. 18); and the overweight group had a lower risk of serum zinc deficiency than the normal group(OR=0. 71, 95%CI 0. 52-0. 96). CONCLUSION: The prevalence of serum zinc deficiency among adults aged 18-60 in China is relatively low. Vitamin A deficiency is a risk factor for zinc deficiency and overweight is a protective factor for zinc deficiency.

Pseudoglucagonoma syndrome: Description of an 'Idiopatic' case.

A case of pseudoglucagonoma syndrome, that is necrolytic migratory erythema, in a patient with no coexistent glucagonoma, is described. The patient was a 59-year-old man with waxing and waning dermatitis of the buttocks, characterised by arciform erythematous papulo-squamous lesions with micro-pustulation. Histopathology was characteristic for necrolytic migratory erythema, but no other underlying disease was detected. Other cases of pseudoglucagonoma syndrome described in literature are briefly reviewed.

Measurement of serum zinc concentration in ruminants: a comparison of results from standard serum and specific trace element collection tubes.

Aims: To evaluate agreement between the concentration of Zn in serum from samples collected from cattle and sheep into standard collection tubes for serum and from samples collected into tubes developed for trace element measurement. Methods: Eighty-eight animals (78 cattle and 10 sheep) on eight farms had paired blood samples collected into standard serum and trace element vacutainers. The paired samples were submitted the same day to the laboratory to be tested for the concentration of Zn in serum using atomic absorption spectrophotometry. The agreement between the paired results was then assessed using limits of agreement analysis. On one farm an additional 10 pairs of samples was taken from the same animals; this second set of paired samples was refrigerated for 48 hours prior to laboratory submission to identify the impact of delaying submission on the apparent concentration of Zn in serum. Results: The limits of agreement analysis found no evidence of a systematic difference between Zn concentrations in serum collected into standard serum tubes and into trace element tubes as neither the intercept nor the slope on the mean-difference plot were significantly different from zero. The SD of the difference between results increased as the concentration of Zn increased, so at the lowest Zn concentration reported in this study (6.9 µmol/L) the limits of agreement were ±1.07 µmol/L, while at the highest (23.5 µmol/L) they were ±3.39 µmol/L. Refrigerating the sample (as whole blood) for 48 hours prior to submission increased the apparent concentration of Zn in serum in both standard serum tubes and trace element tubes by 1.3 µmol/L (95% CI = 0.75-1.85). Conclusions: There was no evidence that the concentration of Zn in serum from standard serum tubes were artificially elevated. In contrast, delaying sample submission by 48 hours did elevate Zn concentrations. Clinical relevance: While these data apply only to the batch of vacutainers used in this study, there is unlikely to be much between batch variation in the potential for contamination. Thus these results suggest that monitoring zinc status in ruminants, by measuring the concentration of Zn in serum from samples collected into standard serum tubes does not result in clinically relevant alterations in Zn concentration compared to using specific trace element tubes. However delaying submission to the laboratory may result in significantly elevated concentrations of Zn in serum so should be avoided.

Changes in serum zinc levels in hepatitis C patients before and after treatment with direct-acting antiviral agents.

AIM: Zinc supplementation therapy has been shown to improve the prognosis of patients with hepatitis C virus (HCV) infection. However, little is known about the changes in serum zinc levels with treatment using direct-acting antiviral agents (DAAs). This prospective study investigated the changes in serum zinc levels before and after treatment with DAAs in hepatitis C patients. METHODS: Thirty-one patients with chronic hepatitis C or HCV-related compensated cirrhosis who were treated with DAAs (glecaprevir/pibrentasvir or elbasvir/grazoprevir) were included in the study. Serum zinc and serum albumin levels were measured before DAA treatment (Baseline), at the end of treatment (EOT), and at 12 weeks after EOT (Follow-up 12). The changes over time in the serum zinc and serum albumin levels were investigated. RESULTS: The mean age of the patients was 68.5 ± 12.1 (range, 40-86) years, and 17 (55%) were women. Based on the Japanese Society of Clinical Nutrition diagnostic criteria, 6 patients had zinc deficiency (<60 µg/dL), and 21 patients had subclinical zinc deficiency (60-80 µg/dL). Significant differences in serum zinc levels were seen between Baseline and EOT (P = 0.01) and between EOT and Follow-up 12 (P = 0.0003). There was no significant difference in serum albumin levels between Baseline and EOT (P = 0.76), but a significant increase was seen between EOT and Follow-up 12 (P = 0.01). CONCLUSIONS: Increases in serum zinc are directly related to DAA treatment and are not a result of increases in albumin. Inhibition of the non-structural protein (NS)3 and NS5A by DAAs could be associated with the improvement of serum zinc levels in hepatitis C patients.

Association between serum zinc levels and lung cancer: a meta-analysis of observational studies.

BACKGROUND: Inconsistent results according to numerous studies that had investigated the association between serum zinc levels and lung cancer risk were reported. The aim of this study was to explore whether serum zinc levels were lower in lung cancer patients than that in controls. METHODS: We systematically retrieved the databases of PubMed, Wanfang, Cochrane, ScienceDirect website, CNKI, and SinoMed databases for comprehensive relevant studies published before December 2018 and conducted a meta-analysis. Standard mean differences (SMD) were pooled using a random effects model. RESULTS: Thirty-two articles were eligible to investigate the correlation between serum zinc levels and lung cancer risk, involving 2894 cases and 9419 controls. The pooled results showed sufficient evidence approving the association between serum zinc levels and lung cancer risk. And the serum zinc levels in lung cancer were significantly lower than that in controls (summary SMD = - 0.88, 95% confidence interval (CI) = - 0.94, - 0.82). Meanwhile, consistent results were obtained both in European populations and Asian populations. No publication bias was detected in our analysis. CONCLUSIONS: The present meta-analysis suggested that serum zinc levels were significantly lower in lung cancer patients than that in controls.

Prevalence and risk factors of anemia and zinc deficiency among 4-6-year-old children of Allahabad District, Uttar Pradesh.

Anemia and zinc deficiency are two of the most daunting nutritional problems afflicting the young children among developing countries like India. Thus, in view of this the following study was designed to investigate the status of undernutrition and micronutrient status (iron and zinc) of children aged between 4 and 6 years of Allahabad district. The anthropometric measurements (height and weight); biochemical parameters (hemoglobin and serum zinc), and general information of the children were recorded. Out of the total 365 children studied, 92.9% were anemic out of which 90.6% (n = 307) were moderately anemic having and 2.3% belonged to mild anemic group. Serum zinc deficiency was 65.3%. Anemia was more commonly observed among undernourished children. In case of zinc deficiency poor nutritional status, the age of 60-71 months and rural settlement projected out to be the potent risk factors.

Association of Serum Zinc Level With Prognosis in Patients With Heart Failure.

BACKGROUND: Zinc is an essential cofactor for energy transfer and physiological heart function, has antioxidant properties, and is involved in multiple signaling pathways. We aimed to investigate the associations between serum zinc levels with prognosis, as well as underlying cardiac function and exercise capacity, in patients with heart failure (HF). METHODS AND RESULTS: We measured serum zinc levels in 968 consecutive hospitalized patients with decompensated HF, who were divided into 3 groups based on serum zinc levels (µg/dL): first (zinc ≥75, n = 323), second (62≤ zinc <75, n = 322), and third (zinc <62, n = 323) tertiles. We examined cardiac function and exercise capacity and followed up on all patients. Although cardiac function did not differ among the 3 groups, peak oxygen consumption was significantly lower in the third tertile than in the first and second tertiles (peak oxygen consumption, 14.2 vs 15.9 and 15.2 mL/kg/min, P = .010). In the Kaplan-Meier analysis (mean duration of follow-up 1103 days), cardiac and all-cause mortality was highest in the third tertile compared with the first and second tertiles. In the Cox proportional hazard analysis, serum zinc level was a predictor of cardiac and all-cause mortality. In the subgroup analysis, there were no interactions concerning associations between serum zinc levels with prognosis and other important variables, including age, gender, comorbidities, medications, other micronutrient levels, B-type natriuretic peptide, and left ventricular ejection fraction. The associations between zinc levels with mortality were consistent in all subgroups. CONCLUSION: Decreased serum zinc levels are associated with high mortality, accompanied by impaired exercise capacity.