Impact of body mass index on growth in boys with delayed puberty

It is unclear whether overweight but otherwise healthy boys with delayed puberty have a variation of constitutional delay of growth and maturation (CDGM) or a different etiology for their pubertal delay. To characterize better this group of boys and investigate whether their growth pattern distinguishes them from boys with typical CDGM, growth data were analyzed in eight overweight (BMI SDS > or = 85th percentile) and 37 non-overweight (BMI SDS <85th percentile) boys with delayed puberty. Primary outcome measures included predicted height (PH) and adult height (AH). At diagnosis of delayed puberty, the overweight boys had less delayed bone ages (chronological age [CA] - bone age [BA] = 1.2 +/- 1.0 vs 2.5 +/- 1.1 years, p <0.01), greater height SDS for CA (-0.5 +/- 0.7 vs -2.4 +/- 0.8, p <0.001), and greater height SDS for BA (0.6 +/- 0.9 vs -0.4 +/- 1.1, p <0.05). PH for the overweight boys exceeded their mid-parental height (MPH) by 5.0 +/- 7.2 cm while non-overweight boys were predicted to fall below their MPH by 2.8 +/- 6.3 cm (p <0.01). Available AH data corroborated the differences in PH, with a trend for overweight boys to have greater height relative to their MPH than the non-overweight boys. These observations suggest that in the context of delayed puberty, being overweight may modulate adult height and/or that the etiology of delayed puberty in overweight boys may differ from typical CDGM.