Calcium and Vitamin D Supplementation Decreases Incidence of Stress Fractures in Female Navy Recruits

NCT ID: NCT00476346

Last Updated: 2015-03-25

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 5201 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2002-05-31
• Study Completion Date: 2006-03-31

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.

Conditions

Stress Fracture

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: TRIPLE

Study Groups

Calcium

Daily calcium supplementation Intervention: Calcium 2000mg / daily

Group Type: ACTIVE_COMPARATOR

Calcium & Vitamin D

Intervention Type: DIETARY_SUPPLEMENT

Calcium 2000mg / daily Vitamin D 800IU / daily

Vitamin D

Daily Calcium and Vitamin D supplementation Intervention: Vitamin D 800IU / daily

Group Type: EXPERIMENTAL

Calcium & Vitamin D

Intervention Type: DIETARY_SUPPLEMENT

Calcium 2000mg / daily Vitamin D 800IU / daily

Interventions

Calcium & Vitamin D

Calcium 2000mg / daily Vitamin D 800IU / daily

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

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

• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: Yes

Sponsors

GlaxoSmithKline

INDUSTRY

Sponsor Role: collaborator

United States Department of Defense

FED

Sponsor Role: collaborator

Creighton University

OTHER

Sponsor Role: lead

Responsible Party

Creighton University

Principal Investigators

Joan M Lappe, Ph.D.

Role: PRINCIPAL_INVESTIGATOR

Creighton University

Locations

Creighton University

Omaha, Nebraska, United States

Countries

United States

Other Identifiers

DAMD-17-01-1-0807

Identifier Type: -

Identifier Source: org_study_id