Bone Metabolism and Parathyroid Hormone-related Protein (PTHrP) Lactation Study

NCT00430417 | Completed DMC

• 2 other identifiers: 0610073R01DK073039
• Study Type: observational
• Target: 49
• Locations: 1 country
• Sites: 1

Brief Summary

The primary aim of the study is to measure bone formation in both lactating and non-lactating post-partum women and compare these to those in healthy non-pregnant controls. The secondary aim is to obtain measurements of Parathyroid Hormone-related Protein (PTHrP), markers of bone resorption, and calcium and vitamin D metabolism in these subjects. The investigators believe that lactating women will have an increase in bone resorption but no increase in bone formation when compared to non-lactating post-partum women and normal controls.

Conditions

Bone Diseases, Endocrine

Keywords

Pregnancy; Lactation; Endocrine System Diseases; MusculoSkeletal System Disease; Hormone; Physiologic Properties

Outcome Measures

Primary Outcomes (1)

• Measurements of amino-terminal telopeptides of procollagen 1 (P1NP), a marker of bone formation, in lactating and non-lactating postpartum women both at 6-8 and at 12-14 weeks post-partum, and to compare these values to those of normal controls

  4 months

Secondary Outcomes (1)

• Measurements of Parathyroid Hormone-related Protein (PTHrP), markers of bone turnover, calcium and vitamin D metabolism

  4 months

Study Arms (3)

3 groups

Group 1: post-partum breastfeeding women

Group 2

Group 2: post-partum bottlefeeding women

Group 3

Group 3: normal non-pregnant controls who are age and race-matched to Group 1

Eligibility Criteria

• Age: 21 Years - 45 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

New mothers who are either almost exclusively breast feeding or bottle feeding; normal controls to match those new mothers.

You may qualify if:

• Healthy Caucasian, Hispanic, or Asian women between the ages of 21-45.
• Group 1: Postpartum (singleton pregnancy) women who are exclusively breastfeeding, defined as 1 or fewer bottles of supplemental formula/day.
• Group 2: Postpartum (singleton pregnancy) women who are non-lactating, which is defined as bottle-feeding or having weaned their baby from breastfeeding for at least 4 weeks prior to study.
• Group 3: Controls - Healthy, non-pregnant women who are race and age-matched to the breastfeeding women in group one. They may not have been lactating or pregnant within the last year.

You may not qualify if:

• Subjects with cardiac, hypertensive, vascular, renal (serum creatinine of \> 1.5), pulmonary, endocrine, musculoskeletal, hepatic, hematologic, or malignant or rheumatologic disease will be excluded from the study.
• Smokers and those with a history of significant alcohol or drug abuse are excluded.
• Baseline hypertension (systolic BP \> 160 mm/Hg) or hypotension (systolic BP \< 90 mm/Hg).
• Subjects taking any chronic medications except stable doses of thyroid hormone, prenatal, vitamin supplements, or oral contraceptives.
• Those who have received any investigational drug in past 90 days will be excluded from the study.
• Women who are currently pregnant will be excluded from the study.
• Women who became pregnant by in vitro fertilization IVF or any hormonal manipulation (i.e. fertility drugs such as clomid) are also excluded, as they may have an altered pre-pregnant hormonal state.
• All women will have a urine pregnancy test performed at each of the two study visits and must not be pregnant in order to continue in the study.
• Subjects are not allowed to donate blood between study visits.
• In order to narrow the statistical variations in the study population, African-Americans are excluded because of demonstrated differences in renal excretion of calcium and vitamin D absorption.

Sponsors & Collaborators

• University of Pittsburgh: lead
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): collaborator

Study Sites (1)

University of Pittsburgh

Pittsburgh, Pennsylvania, 15213, United States

Location

Related Publications (11)

• Dobnig H, Kainer F, Stepan V, Winter R, Lipp R, Schaffer M, Kahr A, Nocnik S, Patterer G, Leb G. Elevated parathyroid hormone-related peptide levels after human gestation: relationship to changes in bone and mineral metabolism. J Clin Endocrinol Metab. 1995 Dec;80(12):3699-707. doi: 10.1210/jcem.80.12.8530622.

  PMID: 8530622 BACKGROUND

• Gundberg CM, Looker AC, Nieman SD, Calvo MS. Patterns of osteocalcin and bone specific alkaline phosphatase by age, gender, and race or ethnicity. Bone. 2002 Dec;31(6):703-8. doi: 10.1016/s8756-3282(02)00902-x.

  PMID: 12531565 BACKGROUND

• Horwitz MJ, Tedesco MB, Sereika SM, Hollis BW, Garcia-Ocana A, Stewart AF. Direct comparison of sustained infusion of human parathyroid hormone-related protein-(1-36) [hPTHrP-(1-36)] versus hPTH-(1-34) on serum calcium, plasma 1,25-dihydroxyvitamin D concentrations, and fractional calcium excretion in healthy human volunteers. J Clin Endocrinol Metab. 2003 Apr;88(4):1603-9. doi: 10.1210/jc.2002-020773.

  PMID: 12679445 BACKGROUND

• Horwitz MJ, Tedesco MB, Sereika SM, Syed MA, Garcia-Ocana A, Bisello A, Hollis BW, Rosen CJ, Wysolmerski JJ, Dann P, Gundberg C, Stewart AF. Continuous PTH and PTHrP infusion causes suppression of bone formation and discordant effects on 1,25(OH)2 vitamin D. J Bone Miner Res. 2005 Oct;20(10):1792-803. doi: 10.1359/JBMR.050602. Epub 2005 Jun 6.

  PMID: 16160737 BACKGROUND

• Kalkwarf HJ, Specker BL, Ho M. Effects of calcium supplementation on calcium homeostasis and bone turnover in lactating women. J Clin Endocrinol Metab. 1999 Feb;84(2):464-70. doi: 10.1210/jcem.84.2.5451.

  PMID: 10022402 BACKGROUND

• Kovacs CS. Calcium and bone metabolism during pregnancy and lactation. J Mammary Gland Biol Neoplasia. 2005 Apr;10(2):105-18. doi: 10.1007/s10911-005-5394-0.

  PMID: 16025218 BACKGROUND

• Kovacs CS, Kronenberg HM. Maternal-fetal calcium and bone metabolism during pregnancy, puerperium, and lactation. Endocr Rev. 1997 Dec;18(6):832-72. doi: 10.1210/edrv.18.6.0319. No abstract available.

  PMID: 9408745 BACKGROUND

• Sowers M. Pregnancy and lactation as risk factors for subsequent bone loss and osteoporosis. J Bone Miner Res. 1996 Aug;11(8):1052-60. doi: 10.1002/jbmr.5650110803. No abstract available.

  PMID: 8854240 BACKGROUND

• Sowers M, Eyre D, Hollis BW, Randolph JF, Shapiro B, Jannausch ML, Crutchfield M. Biochemical markers of bone turnover in lactating and nonlactating postpartum women. J Clin Endocrinol Metab. 1995 Jul;80(7):2210-6. doi: 10.1210/jcem.80.7.7608281.

  PMID: 7608281 BACKGROUND

• Sowers MF, Hollis BW, Shapiro B, Randolph J, Janney CA, Zhang D, Schork A, Crutchfield M, Stanczyk F, Russell-Aulet M. Elevated parathyroid hormone-related peptide associated with lactation and bone density loss. JAMA. 1996 Aug 21;276(7):549-54.

  PMID: 8709404 BACKGROUND

• VanHouten JN, Dann P, Stewart AF, Watson CJ, Pollak M, Karaplis AC, Wysolmerski JJ. Mammary-specific deletion of parathyroid hormone-related protein preserves bone mass during lactation. J Clin Invest. 2003 Nov;112(9):1429-36. doi: 10.1172/JCI19504.

  PMID: 14597768 BACKGROUND

Biospecimen

Retention: SAMPLES WITHOUT DNA

archival blood serum and plasma

MeSH Terms

Conditions

Bone Diseases, Endocrine; Breast Feeding; Endocrine System Diseases; Musculoskeletal Diseases

Condition Hierarchy (Ancestors)

Bone Diseases; Feeding Behavior; Behavior

Study Officials

• Mara J Horwitz, MD

  University of Pittsburgh

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor of Medicne

Study Record Dates

• First Submitted: January 31, 2007
• First Posted: February 1, 2007
• Study Start: January 1, 2007
• Primary Completion: June 1, 2008
• Study Completion: June 1, 2008
• Last Updated: October 31, 2013

Record last verified: 2013-10

Locations

US (1)