Persistent Effect of Vitamin D Supplementation on Musculoskeletal Parameters in Adolescents One Year After Trial Completion

Abstract

We showed a beneficial effect of vitamin D supplementation on musculoskeletal parameters in adolescent girls in a 1-year, randomized, double-blinded placebo-controlled trial (RCT). Our objective for this study was to investigate the residual effect of vitamin D supplementation on bone mineral content (BMC), bone mineral density (BMD), at the lumbar spine and hip, lean mass, and height, 1 year after trial completion. We performed post hoc analyses in 167 adolescents, 86 girls and 81 boys, age 13.9 AE 2 years, who received vitamin D or placebo during the trial, and continued into the follow-up trial. Musculoskeletal parameters were measured at baseline, 12 months (intervention), and 24 months (follow-up). ANOVA and t tests were used to compare results between the placebo group and the merged vitamin D arms (200 or 2000 IU/day), by gender. Baseline characteristics were comparable between treatment groups at entry into the extension. Girls who had received vitamin D during the trial, had significantly larger hip BMC increments compared to those assigned to placebo, at 24 months compared to study entry, but not 24 compared to 12 months, which persisted in adjusted analyses. There were no significant differences in bone mass changes between treatment groups in boys, at 24 months compared to 12 months or to baseline. The beneficial effect of vitamin D supplementation on hip bone mass, achieved in girls during the trial, persisted 1 year after trial completion. These net cumulative increments, 1 year after discontinuation of supplementation, may have important implications on optimizing peak bone mass accretion in adolescent girls.

Vitamin D replacement in children, adolescents and pregnant women in the Middle East and North Africa

“…While supplementation in boys did not yield any significant effect [42], low and high vitamin D doses resulted in a significant improvement in lean mass and total hip bone mineral content (BMC) in girls [24]; interestingly, this effect persisted after 1 year of discontinuation of trial supplementation [43]. Bone specific alkaline phosphatase (BAP) was assessed in 2 studies in children and adolescents [27, 28], falling into 2 different comparisons.…”

Vitamin D in the Middle East and North Africa

“…One study demonstrated substantial improvements in body lean mass and total hip bone mineral content (BMC), in girls only, both in the low dose (400 IU/d) and the high dose (2000 IU/d) arms, compared to placebo, and in total hip area, in the high dose group only ( El-Hajj Fuleihan et al, 2006 ). Interestingly, the latter effect persisted at 1 year after the discontinuation of the intervention ( Ghazal et al, 2016 ). The risk of bias in these trials varied widely ( Chakhtoura et al, 2017b ).…”

Vitamin D in pediatric age: consensus of the Italian Pediatric Society and the Italian Society of Preventive and Social Pediatrics, jointly with the Italian Federation of Pediatricians

“…In 2016, SACN and EFSA revised dietary reference values for vitamin D reporting an increased risk of adverse musculoskeletal health outcomes at serum 25(OH)D levels in the range of deficiency, but with different thresholds (< 10 ng/ml and < 20 ng/ml, respectively) [ 25 , 26 ]. Interestingly, a recent study showed that the beneficial effect of vitamin D on hip bone mass in Lebanese adolescent girls persisted 1 year after discontinuation of supplementation [ 226 ]. At present, some unanswered questions remain [critical times during which supplementation may be most effective, regimen and length of supplementation (continuous or intermittent), gender difference] [ 227 ], thus vitamin D supplementation to optimize bone mass acquisition should be reserved for children at risk for deficiency.…”