A longitudinal perspective of hormone replacement therapies (HRTs) on neuromotor capabilities in males with 47,XXY (Klinefelter syndrome).

PURPOSE: The purpose of this study was to delineate the effects of variable hormone replacement therapies on neuromotor function in a large cohort of males with 47,XXY from birth to adulthood. METHODS: A total of 270 participants aged 16 days to 17 years 11 months prenatally diagnosed with 47,XXY were assessed by their pediatric endocrinologist and were administered hormone replacement therapies accordingly. Infants and school-aged children with 47,XXY were administered neuromotor assessments during routine neurodevelopmental evaluations. For statistical analysis, participants were segregated on the basis of treatment status. Two-tailed t tests, 1-way analysis of variance, and post hoc analysis determined significant group differences on each assessment. RESULTS: In infants, the early hormonal treatment (EHT) group performed significantly better than the untreated group on fine motor and motor composite domains. In school-aged children, we observed significantly improved scores on fine motor control, coordination, agility, and strength domains among males treated with EHT (or any combination thereof) compared with those who did not receive early treatment. CONCLUSION: The highest treated combination group was associated with the highest neuromotor function, although the EHT group also often performed better than the other groups. This suggests EHT may be essential in promoting long-term optimal neuromotor outcome in males with an additional X.

The effect of early hormonal treatment (EHT) on expressive and receptive language capabilities in boys with 47,XXY (Klinefelter syndrome) during infancy and early childhood.

PURPOSE: 47,XXY is associated with variable neurodevelopmental outcomes including deficits in expressive and receptive language development. Early hormonal treatment (EHT) has been associated with mitigating some deficiencies in boys with 47,XXY. This study investigates these language capabilities of 47,XXY boys in the first five years of life and the associated effects of EHT on these capabilities. METHODS: One hundred and seventy-five boys with 47,XXY between the ages of 0 and 5 years, 11 months completed neurodevelopmental assessments specific to age examining their expressive and receptive language capabilities. Subjects were grouped by treatment (EHT and No-T) and differences were analyzed. RESULTS: In the age groups of under 12 months, 24-35 months, 36-47 months, and 60-71 months, the EHT group scored significantly higher on expressive language assessments than the No-T group (p = 0.09, p = 0.0002, p = 0.009, and p = 0.02, respectively). In the age groups of under 12 months and 24-35 months, the EHT group scored significantly better on the auditory comprehension domain of the PLS-4/5 (p = 0.02 and p = 0.05, respectively) than the No-T group. CONCLUSION: Study data suggest EHT may be essential in optimizing receptive and expressive language development in 47,XXY boys during early childhood, which is critical in fostering reading skills and later academic success.