Later puberty is associated with persistently lower bone mineral density (BMD) in adolescence and early adulthood, according to study results published in JAMA Network Open.
Puberty represents a period of rapid skeletal growth and bone remodeling, and late onset may be associated with lower BMD and an increased risk for osteoporosis later in life. Researchers aimed to examine the relationship between timing of puberty and bone accrual in both male and female patients from the Avon Longitudinal Study of Parents and Children (ALSPAC).
For the 6389 patients (50.0% female) included in the study, height measures were collected annually until age 14 years and then at mean age 16, 18, and 25 years. Age at puberty was measured by age at peak height velocity and dual-energy x-ray absorptiometry scans were performed to measure whole-body BMD and bone mineral content (BMC). Secondary outcomes were site-specific BMD and BMC and total hip and femoral neck BMD.
In male and female patients, each one-year increase in age at peak height velocity was associated with 0.050 g/cm2 (95% CI, −0.056 to −0.045 g/cm2) and 0.044 g/cm2 (95% CI, −0.046 to −0.041 g/cm2) lower BMD at age 14 years, respectively. These differences were persistent through early adulthood, with each one-year increase in age at peak height velocity associated with 0.047 g/cm2 (95% CI, −0.051 to −0.043 g/cm2) and 0.034 g/cm2 (95% CI, −0.036 to −0.032 g/cm2) lower BMD at age 25 years for male and female patients, respectively.
Rates of BMD and BMC gains were fastest in both male and female individuals in the oldest pubertal age group, which helped to reduce differences in BMD and BMC between groups. However, by 25 years of age, male and female patients in the oldest pubertal age group had a combined 0.054 g/cm2 (95% CI, −0.60 to −0.49 g/cm2) lower BMD than patients in the youngest pubertal age group, despite having a 90.9 g (95% CI, 79.6 to 102.1 g) higher BMC.
Site-specific trends in bone accrual were similar to those observed in whole-body trajectories. Both male and female patients in the oldest pubertal age group had lower total hip and femoral neck BMD at age 14 years, which persisted through the duration of the study.
The researchers noted that patients from the study sample were mostly of white British ethnicity, which may limit generalizability of results to other populations with regard to bone accrual rates.
“[L]ater puberty was associated with persistently lower BMD from ages 10 to 25 years in male and female participants, despite faster gains in BMD during puberty in those with older pubertal age,” the researchers concluded. “Our findings suggest that advice on how to increase and maintain BMD such as through physical activity should be offered to people with older pubertal age.”
Disclosure: One author reported outside funding from the pharmaceutical industry. Please see the original reference for a full list of disclosures.
Elhakeem A, Frysz M, Tilling K, Tobias JH, Lawlor DA. Association between age at puberty and bone accrual from 10 to 25 years of age. JAMA Netw Open. 2019;2(8):e198918.