Puberty is associated with a marked increase of the female sex predominance in chronic autoimmune thyroiditis.
BACKGROUND
Chronic autoimmune thyroiditis (CAT) displays a strong female predominance with female-to-male (F:M) ratios of 4-20:1 in adults and 2-9:1 in children and adolescents. Both genetic and hormonal factors are involved in this phenomenon. The relation between puberty and F:M ratio in CAT has never been evaluated.


METHODS
The F:M ratio of 133 children with CAT (group A, age at diagnosis 2.4-17.7 years) was compared with that of 113 adult CAT patients (group B, age at diagnosis 21-79 years). Group A included 64 prepubertal (aged 2.4-13.2 years, group A1) and 69 pubertal (aged 9.2-17.4, group A2) children.


RESULTS
The F:M ratio in group A was 3.0, which is significantly (p < 0.001) lower than that (10.3) found in group B patients. The F:M ratio of group A1 prepubertal children was lower (1.6) and significantly different from that of pubertal (6.7, p < 0.01) and adult patients (10.3, p < 0.0001). This phenomenon was more evident in hypothyroid as compared to euthyroid CAT.


CONCLUSIONS
This study provides the first evidence that female predominance of CAT strongly increases during puberty, suggesting a major role for sex hormones in this phenomenon. Further studies are needed to clarify this point.
Mariotti
Stefano
S
Endocrinology, Department of Medical Sciences, University of Cagliari, Cagliari, Italy. mariotti@medicina.unica.it
Prinzis
Alessia
A
Ghiani
Mariangela
M
Cambuli
Valentina M
VM
Pilia
Sabrina
S
Marras
Valeria
V
Carta
Daniela
D
Loche
Sandro
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011627:Puberty / Q000502:physiology*; D012737:Sex Factors; D013967:Thyroiditis, Autoimmune / Q000453:epidemiology*