Micronutrient status in children and adolescents with Down syndrome: systematic review and meta‐analysis

Abstract

Background Down syndrome (DS) is the most common genetic disorder. To date, the scientific literature regarding micronutrient status in children and adolescents with DS has not been systematically reviewed. Therefore, our aim was to provide a systematic review and meta-analysis on this topic. Methods We identified all relevant case-control studies published by 1 January 2022, by searching the PubMed and Scopus databases for original English-language articles analysing the micronutrient status of individuals with DS. Forty studies were included in the systematic review and 31 in the metaanalysis.Results Statistically significant differences between individuals with DS (cases) and non-DS (controls) (P ≤ 0.05) were obtained for zinc, selenium, copper, vitamin B12, sodium and calcium. Serum, plasma and whole blood analyses showed lower zinc levels in cases than controls {standardised mean difference [SMD] serum [95% confidence interval (CI)] = À2.32 [À3.22, À1.41], P < 0.00001; SMD plasma [95% CI] = À1.29 [À2.26, À0.31], P < 0.01; SMD blood [95% CI] = À1.59 [À2.29, À0.89], P < 0.00001}. Similarly, plasma and blood selenium concentrations were significantly lower in cases than controls (SMD plasma [95% CI] = À1.39 [À2.26, À0.51], P = 0.002; SMD blood [95% CI] = À1.86 [À2.59, À1.13], P < 0.00001). Intraerythrocytic copper and serum B12 were higher in cases than controls (SMD Cu [95% CI] = 3.33 [2.19, 4.46], P < 0.00001; SMD B12 [95% CI] = 0.89 [0.01, 1.77], P = 0.048). Blood calcium was lower in cases than controls (SMD Ca [95% CI] = À0.77 [À1.34, À0.21], P = 0.007).Conclusions This study provides the first systematic overview of micronutrient status in children and adolescents with DS and has shown that relatively little consistent research has been executed in this field. There is a clear need for more well-designed, clinical trials to study the micronutrient status and effects of dietary supplements in children and adolescents with DS.

Zinc metabolism and its role in immunity status in subjects with trisomy 21: chromosomal dosage effect

“…It is involved in the maintenance and development of both innate and adaptive immune systems ( 11 ), and its deficiency results in an altered host defense, increased risk of inflammation and even death. In subjects with DS a decreased concentration of this element in serum, plasma and whole blood is reported ( 12 , 13 ).…”

“…According to meta-analysis by Barišić and Saghazadeh, zinc concentration was significantly lower in serum, plasma and whole blood of children and adolescents with trisomy 21 compared to control group ( 12 , 13 ) instead copper (Cu) and zinc levels were higher in trisomic red blood cells ( 12 ). This meta-analysis showed that females and males with trisomy 21 do not differ in Zinc levels and evidence was not conclusive with regards to the effect of age on zinc levels ( 12 ).…”

“…Considering that zinc is part of the SOD1 active enzymatic center, it seems very likely that the elevated zinc and copper levels in red blood cells of subjects with trisomy 21 are due to the increased intraerythrocytic levels and activity of SOD1 ( 23 ). Nevertheless, the increase of SOD1 activity could also lead to excessive zinc consumption because it is part of the active enzymatic center ( 13 ).…”