Bone Response to Soy Isoflavones in Women

NCT ID: NCT00043745

Last Updated: 2013-02-07

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

PHASE2

Total Enrollment

224 participants

Study Classification

INTERVENTIONAL

Study Start Date

2003-03-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

This study will provide valuable data on whether soy isoflavones impact bone loss in postmenopausal women. The study will help clarify potential mechanisms and contribute to our understanding of isoflavones as an alternative to traditional hormone therapy.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Soy protein, rich in isoflavones (estrogen-like compounds), has been shown to prevent bone loss in ovariectomized rats. Short-term preliminary study results in perimenopausal women suggest a bone-sparing effect. Great interest in isoflavones as an alternative to hormone replacement therapy has emerged, yet the long-term efficacy of isoflavones on bone in humans is unknown. Our objective is to determine the three-year efficacy of isoflavone-rich soy extract in attenuating bone loss in postmenopausal women. The central hypothesis is that soy isoflavones will attenuate bone loss in these women by maintaining bone formation, which is modulated by growth factors and isoflavone metabolism. The rationale for this research is that current hormone therapy is fraught with adverse side effects, resulting in non-compliance. This randomized, double-blind, placebo-controlled clinical trial will examine the effects of two doses (80 or 120 mg daily) of isoflavone-rich soy extract on bone in non-osteoporotic postmenopausal women (N=234). The specific aims of this study are: 1) to determine the bone-preserving effects of isoflavones on lumbar spine bone mineral density (BMD); 2) to relate treatment-induced changes in BMD to changes in biochemical markers of bone turnover; 3) to identify potential mechanisms by which isoflavones prevent or modulate bone loss by measuring endogenous estrogens, sex hormone-binding globulin, insulin-like growth factor-I (IGF-I), urinary minerals, serum 25(OH)vitamin D, plasma isoflavones and their metabolites, and customary intake of isoflavone-containing soy; and, 4) to ascertain the safety of isoflavone-rich soy extract. Postmenopausal women will be recruited at two sites (117 at Iowa, 117 at California). Random effects repeated measures analyses will be used to characterize change in BMD as the primary outcome, estimate treatment-induced effects, and depict change in markers of bone turnover in relation to BMD change. We will use intent-to-treat for the primary test, but also account for potential modulators (reproductive hormones, IGF-I, plasma isoflavones) that affect bone, as indicated in specific aim 3.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Osteopenia Osteoporosis

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

PREVENTION

Blinding Strategy

TRIPLE

Participants Investigators Outcome Assessors

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

1

Participants will receive moderate dose soy isoflavone (80 mg/day) tablets, extracted from soy protein

Group Type EXPERIMENTAL

Soy isoflavones

Intervention Type DIETARY_SUPPLEMENT

Soy isoflavones extracted from soy protein, compressed into tablets; three tablets taken daily

2

Participants will receive high dose soy isoflavone (120 mg/day) tablets, extracted from soy protein

Group Type EXPERIMENTAL

Soy isoflavones

Intervention Type DIETARY_SUPPLEMENT

Soy isoflavones extracted from soy protein, compressed into tablets; three tablets taken daily

3

Participants will receive soy extract devoid of isoflavones to serve as placebo

Group Type PLACEBO_COMPARATOR

Extract tablets

Intervention Type DIETARY_SUPPLEMENT

Extract from soy protein, but devoid of isoflavones; three tablets taken once daily

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Soy isoflavones

Soy isoflavones extracted from soy protein, compressed into tablets; three tablets taken daily

Intervention Type DIETARY_SUPPLEMENT

Extract tablets

Extract from soy protein, but devoid of isoflavones; three tablets taken once daily

Intervention Type DIETARY_SUPPLEMENT

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Early postmenopausal (i.e., no menses during past 12 months) women, with an upper limit of 10 years since their last cycle
* Natural menopause (i.e., no hysterectomies or oophorectomies)
* Body mass index (BMI) \> 20 and \< 30

Exclusion Criteria

* Current or previous (within 12 months) use of hormone replacement therapy, hormonal contraceptives, estrogens, or progestogens
* Current use of pharmacologic agents, such as selective estrogen-receptor modulators (SERMs) (e.g., raloxifene or tamoxifen) or anti-resorptive agents (e.g., alendronate or calcitonin), herbal therapies that may have estrogenic effects (e.g., herbimycin, tryphostins), or cigarettes
* Strict vegans (but will include lacto-ovo-, lacto-, and ovo-vegetarians)
* Metabolic bone disease, renal disease, history of urolithiasis, cancer, cardiovascular disease, diabetes mellitus, respiratory disease, gastrointestinal disease, liver disease, or other chronic diseases
* First-degree relative with breast cancer
* Lumbar spine BMD \>= -1.5 standard deviations (SD) below mean (high-risk for osteoporosis) and BMD \>= +1.0 SD above mean
Minimum Eligible Age

45 Years

Maximum Eligible Age

65 Years

Eligible Sex

FEMALE

Accepts Healthy Volunteers

Yes

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)

NIH

Sponsor Role collaborator

Iowa State University

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Dr. Manju B. Reddy

Professor

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

D. Lee Alekel, PhD

Role: PRINCIPAL_INVESTIGATOR

Iowa State University

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

USDA/ARS/WHNRC University of California-Davis

Davis, California, United States

Site Status

Iowa State University

Ames, Iowa, United States

Site Status

Countries

Review the countries where the study has at least one active or historical site.

United States

References

Explore related publications, articles, or registry entries linked to this study.

Alekel DL, Genschel U, Koehler KJ, Hofmann H, Van Loan MD, Beer BS, Hanson LN, Peterson CT, Kurzer MS. Soy Isoflavones for Reducing Bone Loss Study: effects of a 3-year trial on hormones, adverse events, and endometrial thickness in postmenopausal women. Menopause. 2015 Feb;22(2):185-97. doi: 10.1097/GME.0000000000000280.

Reference Type DERIVED
PMID: 25003624 (View on PubMed)

Matvienko OA, Alekel DL, Genschel U, Ritland L, Van Loan MD, Koehler KJ. Appetitive hormones, but not isoflavone tablets, influence overall and central adiposity in healthy postmenopausal women. Menopause. 2010 May-Jun;17(3):594-601. doi: 10.1097/gme.0b013e3181c92134.

Reference Type DERIVED
PMID: 20142790 (View on PubMed)

Alekel DL, Van Loan MD, Koehler KJ, Hanson LN, Stewart JW, Hanson KB, Kurzer MS, Peterson CT. The soy isoflavones for reducing bone loss (SIRBL) study: a 3-y randomized controlled trial in postmenopausal women. Am J Clin Nutr. 2010 Jan;91(1):218-30. doi: 10.3945/ajcn.2009.28306. Epub 2009 Nov 11.

Reference Type DERIVED
PMID: 19906801 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

R01AR046922

Identifier Type: NIH

Identifier Source: secondary_id

View Link

NIAMS-073

Identifier Type: -

Identifier Source: secondary_id

R01AR046922

Identifier Type: NIH

Identifier Source: org_study_id

View Link

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.