Clinical trial NCT00476346: Calcium and Vitamin D Supplementation Decreases Incidence of Stress Fractures in Female Navy Recruits
Official title: Calcium and Vitamin D Supplementation Decreases Incidence of Stress Fractures in Female Navy Recruits
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Stress Fracture
Keywords: physical training
military training
bone
fracture prevention
young adult
Lead sponsor: Creighton University
Sponsor class: OTHER
Collaborators: name: GlaxoSmithKline
name: United States Department of Defense
First posted: 2007-05-22
Enrollment: 5201
Sex: FEMALE
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: We conducted a double-blind, placebo-controlled randomized clinical trial of calcium and vitamin D supplementation in 5201 female Naval recruits. During 8 weeks of basic training, supplementation with 2000 mg calcium and 800 IU vitamin D/day decreased incidence of stress fracture by 25%. The hypothesis was:

Supplementation with calcium 2000 mg/d and vitamin D 800 IU/d will significantly reduce the incidence of stress fractures in female Navy recruits during 8 weeks of basic training.

Detailed description: Introduction: Stress fractures (SFx) are one of the most common and debilitating overuse injuries seen in military recruits, and they are also problematic for non-military athletic populations. The goal of this randomized double-blind, placebo-controlled study was to determine if a calcium and vitamin D intervention could reduce the incidence of SFx in female recruits during basic training.

Methods: We recruited 5201 female Navy recruit volunteers and randomized them to a 2000 mg calcium and 800 IU vitamin D supplement/day or placebo. SFx were ascertained when recruits reported to the Great Lakes clinic with symptoms. All SFx were confirmed with radiography or technetium scan according to the usual Navy protocol.

Results: A total of 309 subjects were diagnosed with a SFx resulting in an incidence of 5.9% per eight weeks. Using "intention-to-treat" analysis by including all enrolled subjects, Fisher's Exact test found that the calcium and vitamin D group had a 25% lower incidence of SFx than the control group (6.6% vs 5.3%, respectively, p=0.03). The per protocol analysis, including only the 3700 recruits who completed the study, found a 27% lower incidence of fractures in the supplemented vs the control group (8.6% vs 6.8%, respectively, p=0.02).

Conclusions: Generalizing the findings to the population of 14,416 females who entered basic training at the Great Lakes during the 24 months of recruitment, calcium and vitamin D supplementation for the entire cohort would have prevented about 130 persons per year from fracturing. Such a decrease in SFx would be associated with a significant decrease in morbidity and financial costs.

Eligibility criteria: Inclusion Criteria:

* Female entering basic recruit training at the Great Lakes Naval Station

Primary outcomes:
measure: individuals with stress fracture
timeFrame: one year
Secondary outcomes:
Other outcomes:
Locations:
city: Omaha
country: United States
facility: Creighton University
state: Nebraska
Study officials:
affiliation: Creighton University
name: Joan M Lappe, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References: