In a small cross-sectional study of 10- to 16-year-old girls with and without type 1 diabetes, both groups were equally physically active, based on their replies to the bone-specific physical activity questionnaire (BPAQ).
However, among the more sedentary girls (with BPAQ scores below the median), those with type 1 diabetes had worse markers of bone health in imaging tests compared with the girls without diabetes.
the researchers summarize in a poster presented at the annual meeting of the American Society of Bone and Mineral Research.
However, this is early research and further study is needed, the group cautions.
“Ongoing studies with objective measures of physical activity as well as interventional studies will clarify whether increasing physical activity may improve bone health and reduce fracture risk in this vulnerable group,” they conclude.
“If you look at the sedentary kids, there’s a big discrepancy between the kids who have diabetes and the control kids, and that’s if we’re looking at radius or tibia or trabecular bone density or estimated failure load,” senior author Deborah M. Mitchell, MD, said in an interview at the poster session.
However, “when we look at the kids who are more physically active, we’re really not seeing as much difference [in bone health] between the kids with and without diabetes,” said Dr. Mitchell, a pediatric endocrinologist at Massachusetts General Hospital and assistant professor at Harvard Medical School, Boston.
But she also acknowledged, “There’s all sorts of caveats, including that this is retrospective questionnaire data.”
However, if further, rigorous studies confirm these findings, “physical activity is potentially a really effective means of improving bone quality in kids with type 1 diabetes.”
“This study suggests that bone-loading physical activity can substantially improve skeletal health in children with [type 1 diabetes] and should provide hope for patients and their families that they can take some action to prevent or mitigate the effects of diabetes on bone,” coauthor and incoming ASBMR President Mary L. Bouxsein, PhD, told this news organization in an email.
“We interpret these data as an important reason to advocate for increased time in moderate to vigorous bone-loading activity,” said Dr. Bouxsein, professor, department of orthopedic surgery, Harvard Medical School, Boston, “though the ‘dose’ in terms of hours per day or episodes per week to promote optimal bone health is still to be determined.”
“Ongoing debate,” “need stronger proof”
Asked for comment, Laura K. Bachrach, MD, who was not involved with the research, noted: “Activity benefits the development of bone strength through effects on bone geometry more than ‘density,’ and conversely, lack of physical activity can compromise gains in cortical bone diameter and thickness.”
However, “there is ongoing debate about the impact of type 1 diabetes on bone health and the factor(s) determining risk,” Dr. Bachrach, a pediatric endocrinologist at Stanford Children’s Health, Palo Alto, Calif., told this news organization in an email.
The current findings suggest “that physical activity in adolescent girls provided protection against potential adverse effects of type 1 diabetes,” said Dr. Bachrach, who spoke about bone fragility in childhood in a video commentary in 2021.
Study strengths, she noted, “include the rigor and expertise of the investigators, use of multiple surrogate measures that capture bone geometry/microarchitecture, as well as the inclusion of healthy local controls.”
“The study is limited by the cross-sectional design and subjects who opted, or not, to be active,” she added. “Stronger proof of the protective effects of activity on bone health in type 1 diabetes would require a randomized longitudinal intervention study, as alluded to by the authors of the study.”