Testosterone Therapy Protects Bones in Prader-Willi Boys
A real-world study of 59 males with Prader-Willi syndrome links testosterone treatment to maintained bone density and higher lean mass.
Updated on Nov. 2, 2026 in Weight Loss
Researchers reported that testosterone therapy maintained bone mineral density and increased lean mass in males with Prader-Willi syndrome. Minor behavioral effects were seen in most participants, and behavior scores did not change compared with baseline.
Why it matters
Hypogonadism can prevent boys with Prader-Willi syndrome from reaching optimal bone mineral density during development. The findings suggest testosterone may help address body composition and skeletal health in this population.
The study drew on real-world observational data from patient records and DXA scans across three Dutch cohorts, showing lean mass rose 0.47 SD points over five years while trabecular bone density fell 0.28 points. Researchers have not yet established the optimal starting age or which patients gain the most.
The details
Researchers collected real-world data from 59 males older than 14 with Prader-Willi syndrome across three cohorts in the Netherlands, with a median age of 22.57 years. Of the 44 testosterone users, 52.3% started transdermal treatment, 31.8% intramuscular and 15.9% oral, and 48.8% had challenging behavior before therapy began.
Timeline
Study outcomes were measured at 2 years, 4 years and 5 years of follow-up.
Big Picture
The results extend Netherlands-based Prader-Willi cohort research by linking hormone treatment to skeletal and body composition outcomes in real-world patients. The data add to a limited evidence base on how hypogonadism management affects long-term development in this genetic condition.
For families managing Prader-Willi syndrome, the findings suggest testosterone therapy may support bone strength and lean mass, though transdermal, intramuscular and oral routes were all used in practice. Families should discuss timing and suitability with their clinicians, since the optimal starting age remains unclear.
The takeaway
Hormone therapy can help preserve bone and muscle in males with Prader-Willi syndrome, but clinicians still need better guidance on when to begin and who benefits most.
Further reading
Explore more on Weight Loss to see how body composition research connects to broader health topics.
Source note: This article includes information reported by Healio.
