Chromium, nickel and cadmium in biological fluids in patients with rheumatoid arthritis compared to healthy controls

Heavy metals in fish and its association with autoimmunity in the development of juvenile idiopathic arthritis: a prospective birth cohort study

BACKGROUND

The etiology of Juvenile Idiopathic Arthritis (JIA) is poorly understood. The purpose of this study was to examine the possible influence of early nutrition on later development of JIA.

METHODS

In a population-based prospective birth cohort of 15,740 children we collected nutritional data, including fish consumption, and biological samples during pregnancy, at birth and at different ages. 16 years after study inclusion we identified 42 children with JIA, of whom 11 were positive for Antinuclear Antibodies (ANA). Heavy metals were analysed in cord blood of all 42 JIA patients and 40 age and sex-matched controls. A multivariable logistic regression model, adjusted for relevant factors, was used as well as Mann-Whitney U-test.

RESULTS

Fish consumption more than once a week during pregnancy as well as during the child's first year of life was associated with an increased risk of JIA (aOR 4.5 (1.95-10.4); p < 0.001 and aOR 5.1 (2.1-12.4) p < 0.001) and of ANA-positivity (aOR 2.2 (1.4-3.6); p = 0.002 and p < 0.001). Concentrations of Al, Cd, Hg and Li in cord blood were significantly higher in the JIA-group than in controls. The ANA-positive, all of whom had consumed fish >once/week their first year, had significantly higher concentrations of Al (p < 0.001), Cd (p = 0.003), and Li (p < 0.001) in cord blood than controls. Frequency of fish consumption correlated with concentrations of Cd (p = 0.003), Li (p = 0.015) and Hg (p = 0.011).

CONCLUSIONS

Moderate exposure to heavy metals, associated with fish consumption, during pregnancy and early childhood may cause effects on the immune system of the offspring, resulting in ANA positivity and JIA.

Prevalence of rheumatoid arthritis in relation to serum cadmium concentrations: cross-sectional study using Korean National Health and Nutrition Examination Survey (KNHANES) data

OBJECTIVES

It has been suggested that exposure to heavy metal cadmium (Cd) may contribute to a high risk of developing rheumatoid arthritis (RA). This study was to investigate the association of RA prevalence and serum concentrations of Cd and other heavy metals through large survey data analysis.

DESIGN

A retrospective cross-sectional survey study.

SETTING

Large population survey in Korea.

PARTICIPANTS

53 829 subjects participated in Korean National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2013.

INTERVENTIONS

Heavy metals were measured in different time periods of the survey programme which resulted in three different data sets for analysis: Cd, mercury (Hg) and lead (Pb) from 2008 to 2012 survey; serum manganese (Mn) and urine arsenic (As) from 2008 to 2009 survey; and serum zinc (Zn) from 2010 survey. RA prevalence and its associations with serum heavy metals were analysed using a general linear/logistic regression model of complex sample design.

RESULTS

Serum Cd was elevated in patients with RA (RA vs control: 1.30±0.07 µg/L vs 1.17±0.01 µg/L, p<0.01). There were no significant differences in urine levels of As or serum levels of Pb, Hg, Mn or Zn between patients with RA and controls. OR (95% CI) of RA prevalence according to 1 µg/L increase of serum Cd level was 1.28(95% CI 1.03 to 1.61). Prevalence of RA in women was increased with increasing quartiles of Cd levels, with a 19-fold difference in female RA prevalence between individuals in the lowest quartile of serum Cd level and those in the highest quartile (0.18% vs 3.42%). Cubic spline curve of prevalence OR showed increased risk of RA according to increased serum Cd level. Increased risk of RA in men was not observed with increased serum Cd levels.

CONCLUSION

There was an increased prevalence of RA in females associated with increased serum levels of Cd in the Korean population.

Serum nickel levels of diabetic patients and healthy controls by AAS with a graphite furnace

In this study, serum nickel levels of diabetic patients and healthy controls were determined by AAS with a graphite furnace. The serum nickel concentrations were found to be 1.15 +/- 1.89 micrograms/L in healthy controls and 0.82 +/- 0.74 microgram/L in diabetics. There was, however, no statistically significant difference between the two groups (p = 0.13). The relationship of nickel levels to diabetes type and duration, diabetic complications and treatment, sex, age, and heredity was investigated. However, again no significant differences were found, nor was there any correlation between serum nickel levels and blood sugar, HBa1c, fructosamine, sialic acid levels, and age.