PTH And Calcium Responses to Exercise in Older Adults Experiment 2 (PACE Sr. 2)

Osteoporosis Clinical Trial

Official title:

PTH And Calcium Responses to Exercise in Older Adults Experiment 2 (PACE Sr. 2)

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT02580604
• Other study ID #: 15-0878
• Secondary ID: UM1TR004399
• Status: Recruiting
• Phase: Early Phase 1
• Start date: November 2015
• Est. completion date: September 30, 2024

Study information

• Verified date: June 2024
• Source: University of Colorado, Denver
• Contact: Sarah J Wherry, PhD
• Phone: 303-724-1927
• Email: sarah.wherry[@]ucdenver.edu
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Declines in serum calcium during exercise may cause increases in markers of bone resorption. This study will determine if preventing the decline serum ionized calcium experienced at the onset of exercise through the use of a "calcium clamp" also prevents increases in blood biomarkers associated with bone resorption.

Description:

Participants will undergo two identical walking exercise sessions on a treadmill. One session will occur until continuous calcium infusion and the other will be under continuous saline infusion. C-telopeptide, parathyroid hormone, total calcium, and serum ionized calcium will be monitored to distinguish differences in bone activity under the two conditions.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 35
• Est. completion date: September 30, 2024
• Est. primary completion date: June 30, 2024
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 60 Years to 80 Years

Eligibility

Inclusion Criteria:

• Healthy adults aged 60-80 y

• Currently taking a bisphosphonate medication

Exclusion Criteria:

• Use of medications (other than bisphosphonates) in the past 6 months known to affect bone metabolism (e.g., thiazide diuretics, oral glucocorticoids)

• Bone Mineral Density (BMD) t score < -3.0 at the total hip or lumbar spine

• Known disease or condition associated with intestinal malabsorption

• Moderate or severe renal impairment defined as an estimated glomerular filtration rate of <60 mL/min/1.73m2 based on the Modified Diet in Renal Disease (MDRD) equation

• Chronic hepatobiliary disease, defined as liver function tests (AST, ALT) >1.5 times the upper limit of normal; if such values are obtained on initial screening and thought to be transient in nature, repeated testing will be allowed

• Thyroid dysfunction, defined as an ultrasensitive TSH <0.5 or >5.0 mU/L; volunteers with abnormal TSH values will be re-considered for participation in the study after follow-up evaluation by the PCP with initiation or adjustment of thyroid hormone replacement

• Serum calcium <8.5 or >10.3 mg/dL Serum 25(OH)D <20 ng/mL; volunteers with abnormal serum 25(OH)D values may be re-considered for participation in the study if serum 25(OH)D is >20 ng/mL after vitamin D supplementation

• Uncontrolled hypertension defined as resting systolic BP >150 mmHg or diastolic BP>90 mmHg; participants who do not meet these criteria at first screening will be re-evaluated, including after follow-up evaluation by the PCP with initiation or adjustment of anti-hypertensive medications

• History of type 1 or type 2 diabetes

• Cardiovascular disease; subjective or objective indicators of ischemic heart disease (e.g., angina, ST segment depression) or serious arrhythmias at rest or during the graded exercise test (GXT) without follow-up evaluation will be cause for exclusion; follow-up evaluation must include diagnostic testing (e.g., stress echocardiogram or thallium stress test) with interpretation by a cardiologist

• Diagnosis or history of asthma

Related Conditions & MeSH terms

• Osteoporosis

Intervention

Drug:
• Calcium Chloride/Calcium Gluconate
Calcium (as either calcium chloride or calcium gluconate in half normal saline) will be delivered via IV during exercise to keep serum ionized calcium levels above baseline. The clamp is modeled after the hyperglycemic glucose clamp.
• Placebo
Saline Infusion

Locations

Country	Name	City	State
United States	University of Colorado Hospital	Aurora	Colorado

Sponsors (2)

Lead Sponsor	Collaborator
University of Colorado, Denver	National Center for Advancing Translational Sciences (NCATS)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in Parathyroid Hormone (PTH)	PTH will be measured during baseline, throughout exercise, and during recovery at regular intervals. The investigators are looking to see how PTH changes over the course of the exercise and recovery period in both the calcium and saline. The investigators anticipate that PTH will be higher in the saline condition versus the calcium. The investigators expect that men and women will respond similarly.	At baseline, through 60 minutes of exercise, and during 4 hours of recovery
Secondary	Change in C-telopeptide (CTX)	CTX will be measured during baseline, throughout exercise, and during recovery at regular intervals. The investigators are looking to see how PTH changes over the course of the exercise and recovery period in both the calcium and saline. The investigators anticipate that CTX will be higher in the saline condition versus the calcium. The investigators expect that men and women will respond similarly.	At baseline, through 60 minutes of exercise, and during 4 hours of recovery
Secondary	Change in Total Calcium (Ca)	Total Ca will be measured during baseline, throughout exercise, and during recovery at regular intervals. The investigators are looking to see how Ca changes over the course of the exercise and recovery period in both the calcium and saline conditions.	At baseline, through 60 minutes of exercise, and during 4 hours of recovery