PTH And Calcium Responses to Exercise (PACE) in Older Adults

NCT ID: NCT02468817

Last Updated: 2018-03-14

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 12 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2015-08-31
• Study Completion Date: 2018-01-31

Brief Summary

Exercise that causes a decline in serum Calcium (Ca) as a result of dermal Ca loss stimulates bone resorption via an increase in Parathyroid Hormone (PTH).

Detailed Description

Determine whether the magnitude of dermal Ca loss (i.e., sweating) during exercise is a determinant of the decline in iCa and increases in PTH and carboxy-terminal collagen crosslinks (CTX; marker of bone resorption). The proposed experiment will address this by manipulating the rate of dermal Ca loss (moderate vs high sweating rate) to determine whether this is the trigger for the cascade described in Figure 1. This will be achieved by having participants perform two identical exercise bouts under different thermal conditions (warm vs cool).

Conditions

Osteoporosis

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: PREVENTION
• Blinding Strategy: NONE

Study Groups

Treadmill Exercise

2 (two) 1-hour of vigorous exercise bouts under different thermal conditions, one at 16 degrees C and one at 26 degrees C.

Group Type: ACTIVE_COMPARATOR

Treadmill Exercise

Intervention Type: PROCEDURE

2 (two) 1-hour of vigorous exercise bouts under different thermal conditions

Magnitude of Ca loss during Exercise at 26 degrees Celcius

Blood samples at 15-min intervals starting 15 min before exercise and ending 60 min after exercise.

Group Type: EXPERIMENTAL

Magnitude of Ca loss during Exercise at 26 degrees Celcius

Intervention Type: PROCEDURE

Blood samples at 15-min intervals starting 15 min before exercise and ending 60 min after exercise

Interventions

Treadmill Exercise

2 (two) 1-hour of vigorous exercise bouts under different thermal conditions

Intervention Type: PROCEDURE

Magnitude of Ca loss during Exercise at 26 degrees Celcius

Blood samples at 15-min intervals starting 15 min before exercise and ending 60 min after exercise

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• Healthy adults aged 60-80 y

Exclusion Criteria

• Use of medications in the past 6 months known to affect bone metabolism (e.g., bisphosphonates, thiazide diuretics, oral glucocorticoids)
• BMD t score < -2.5 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 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

• Minimum Eligible Age: 60 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Colorado, Denver

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Sarah J Wherry, PhD

Role: PRINCIPAL_INVESTIGATOR

University of Colorado, Denver

Locations

University of Colorado Hospital

Aurora, Colorado, United States

Countries

United States

Other Identifiers

15-0250

Identifier Type: -

Identifier Source: org_study_id