Vitamin D insufficiency and elevated vitamin D metabolite ratios (VMR) are associated with increased risk of injuries: Results from the British Army Lower Limb Iinjury Pprevention (ALLIP) study

Jonathan Tang, Sarah Jackson, Rachel Izard, Samuel Oliver, Isabelle Piec, Christopher Washbourne, Neil Walsh, Julie Greeves, William Fraser

Research output: Contribution to journalAbstractpeer-review


Introduction: British Army recruits suffer from musculoskeletal injuries (MSI) during initial training. Up to 10% suffer skeletal stress fracture (SFx) resulting in lost training days and medical attrition. There is evidence to suggest that vitamin D deficiency is prevalent in the army. Our aim was to determine vitamin D metabolites (VDM) in recruits upon starting training, and health outcomes after a 14-week training programme.

Methods: 940 of 2252 healthy army recruits, age 18–32 yrs were included in the analysis ( ID: NCT02416895). Excluded were those who took calcium/vitamin D supplements and with prior injuries. Serum 25OHD/24,25(OH)2D, 1,25(OH)2D and PTH were tested across all seasons. The co-primary endpoints were incidence of SFx, MSI, infections and days lost in rehabilitation (DLR) in relation to VDM.

Results: 38% of participants identified as vitamin D insufficient (25OHD<50 nmol/L) were associated with increased risk(OR): SFx(1.03), medial tibial stress syndrome (MTSS)(1.26), upper limb trauma (1.02), respiratory infections (1.13); and highly significant risk of upper limb overuse injuries(3.18) and subsequent DLR(3.49). 25OHD:24,25(OH)2D VMR was significantly increased at 25OHD<50 nmol/L (P<0.001). There was no significant relationship between 1,25(OH)2D and 25OHD, the distribution of 1,25(OH)2D:24,25(OH)2D VMR showed an exponential negative correlation with 25OHD (y=1525.8×−0.983, r2Exp =0.582, P<0.001). PTH was significantly higher (P>0.001) in subjects with high 1,25(OH)2D:24,25(OH)2D VMR and low 25OHD than those at the opposite. Cosinor-fit curves revealed circannual rhythm on all VDM and VMR except for 1,25(OH)2D. Baseline BMD was not associated with any health outcomes.

Conclusion: Vitamin D insufficiency is strongly associated with training-related injuries and lengthened rehabilitation. By using VMR models we demonstrated possible underlying mechanisms preceding the accelerated injury.
Original languageEnglish
JournalJournal of Bone and Mineral Research
Publication statusPublished - 2018
EventSociety for Endocrinology: BES 2018 Conference - Glasgow, United Kingdom
Duration: 19 Nov 201821 Nov 2018

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