Serum zinc, copper, zinc-to-copper ratio, and other essential elements and minerals in children with attention deficit/hyperactivity disorder (ADHD)

Anatoly V Skalny; Anna L Mazaletskaya; Olga P Ajsuvakova; Geir Bjørklund; Margarita G Skalnaya; Jane C-J Chao; Lyubov N Chernova; Roza A Shakieva; Philippe Yu Kopylov; Andrey A Skalny; Alexey A Tinkov

doi:10.1016/j.jtemb.2019.126445

Serum zinc, copper, zinc-to-copper ratio, and other essential elements and minerals in children with attention deficit/hyperactivity disorder (ADHD)

J Trace Elem Med Biol. 2020 Mar:58:126445. doi: 10.1016/j.jtemb.2019.126445. Epub 2019 Dec 6.

Authors

Affiliations

¹ Yaroslavl State University, 150003, Yaroslavl, Russia; IM Sechenov First Moscow State Medical University (Sechenov University), 119146, Moscow, Russia; RUDN University, Moscow, Russia; Taipei Medical University, Taipei, Taiwan.
² Yaroslavl State University, 150003, Yaroslavl, Russia.
³ Yaroslavl State University, 150003, Yaroslavl, Russia; IM Sechenov First Moscow State Medical University (Sechenov University), 119146, Moscow, Russia.
⁴ Council for Nutritional and Environmental Medicine, Mo I Rana, Norway.
⁵ IM Sechenov First Moscow State Medical University (Sechenov University), 119146, Moscow, Russia; RUDN University, Moscow, Russia.
⁶ Taipei Medical University, Taipei, Taiwan.
⁷ RUDN University, Moscow, Russia.
⁸ Kazakh Academy of Nutrition, Almaty, Kazakhstan.
⁹ IM Sechenov First Moscow State Medical University (Sechenov University), 119146, Moscow, Russia.
¹⁰ Yaroslavl State University, 150003, Yaroslavl, Russia; RUDN University, Moscow, Russia.
¹¹ Yaroslavl State University, 150003, Yaroslavl, Russia; IM Sechenov First Moscow State Medical University (Sechenov University), 119146, Moscow, Russia. Electronic address: tinkov.a.a@gmail.com.

PMID: 31869738
DOI: 10.1016/j.jtemb.2019.126445

Abstract

Background: Essential trace elements and minerals play a significant role in neurodevelopment. Although certain studies demonstrated impaired essential trace element and mineral status in children with ADHD, the existing data are insufficient. The objective of the present study was to assess serum trace element and mineral levels in children with ADHD.

Methods: Serum trace element and mineral levels in 68 children with ADHD and 68 neurotypical controls were assessed using ICP-MS at NexION 300D (PerkinElmer Inc., USA) equipped with ESI SC-2 DX4 autosampler (Elemental Scientific Inc., USA).

Results: Serum Cr, Mg, and Zn levels in children with ADHD were 21 % (p = 0.010), 4 % (p = 0.005), and 7 % (p = 0. 001) lower as compared to the healthy controls, respectively. In turn, serum Cu/Zn values were 11 % higher than those in the control group. Age and gender had a significant impact on serum element levels in ADHD. Particularly, preschool children were characterized by significantly increased Cu (+8 %; p = 0.034), and Cu/Zn (+19 %; p < 0.001) values, whereas serum Zn (-9 %; p = 0.004) level was decreased. In primary school-aged children only 6 % (p = 0.007) lower Mg levels were observed. Both boys and girls with ADHD were characterized by 8 % (p = 0.016) lower serum Zn levels and 10 % (p = 0.049) higher Cu/Zn values when compared to neurotypical girls. Boys with ADHD also had significantly higher Cu/Zn, exceeding the respective control values by 12 % (p = 0.021), predominantly due to a 7 % (p = 0.035) decrease in serum Zn. Serum Mg levels were also found to be significantly lower than those in neurotypical children by 5 % (p = 0.007). In adjusted regression models serum Cr (β=-0.234; p = 0.009) and Cu/Zn (β = 0.245; p = 0.029) values were significantly associated with ADHD, respectively. Two-way ANOVA revealed a significant impact of ADHD on Cr, Mg, Zn, and Cu/Zn, whereas age was associated with Cu, I, Mg, Mo, and Cu/Zn, whereas gender accounted only for variability in serum Mn levels. Principal component analysis (PCA) also revealed significant contributions of Mg, Zn, and Cu/Zn values to ADHD variability.

Conclusions: Hypothetically, the observed decrease of essential trace elements, namely Mg and Zn, and elevation of Cu/Zn may significantly contribute to the risk of ADHD or its severity and/or comorbidity.

Keywords: Chromium; Copper; Magnesium; Neurodevelopment; Zinc.

MeSH terms

Attention Deficit Disorder with Hyperactivity / blood*
Case-Control Studies
Child
Child, Preschool
Copper / blood*
Female
Humans
Male
Minerals / blood*
Principal Component Analysis
Regression Analysis
Trace Elements / blood*
Zinc / blood*

Substances

Minerals
Trace Elements
Copper
Zinc