Clinical trial NCT00549536: The Effect of Calcium Supplementation on Insulin Resistance and 24h Blood Pressure
Official title: The Effect of Oral Calcium Supplementation on Insulin Sensitivity, Intracellular Cationic Concentrations and the Transmembrane Sodium/Hydrogen Exchanger Activity in Subjects With Type 2 Diabetes and Hypertension
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Hypertension
Diabetes
Insulin Resistance
Keywords: calcium supplementation
intracellular ions
sodium/hydrogen exchange activity
Lead sponsor: Aristotle University Of Thessaloniki
Sponsor class: OTHER
Collaborators: name: Hellenic Society of Hypertension
First posted: 2007-10-26
Enrollment: 31
Sex: ALL
Minimum age (years): 18
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Increased levels of intracellular calcium are thought to diminish maximal cellular response to insulin and induce insulin resistance. Also, both hypertension and diabetes are thought to be conditions of altered intracellular ionic state. The aim of the present study is to investigate the possible effect of oral calcium supplementation on intracellular ions, insulin sensitivity, 24-h blood pressure and sodium/hydrogen exchanger activity in patients with type 2 diabetes and essential hypertension.


Eligibility criteria: Inclusion Criteria:

* Patients with hypertension, diabetes and the metabolic syndrome (according to the definition of the National Cholesterol Education Program, Adult Panel III (NCEP, ATP III).
* Signed the concent form

Exclusion Criteria:

* Secondary Hypertension
* Stage II or III hypertension
* History of renal disease
* Sleep apnea
* Acute or chronic inflammation
* History of coronary artery disease
* Heart failure stage III or IV according to the New York Heart Association
* Active liver disease
* History of malignancy
* Parathyroidism
* History of kidney stones
* Calcium supplement ingestion
* Drugs that alter insulin resistance
* Treatment with insulin
* Alcohol abuse or other conditions with poor prognosis
* Treatment with non-inflammatory steroid agents, corticosteroids, or any other treatment that affects blood pressure

Primary outcomes:
measure: To evaluate the difference in 24h blood pressure measurement and insulin sensitivity between the treatment and the control group.
timeFrame: baseline and after 8 weeks of follow up
Secondary outcomes:
measure: To evaluate differences in intracellular calcium, magnesium, sodium and potassium concentrations at the end of the follow up period between the calcium supplementation group and the control group.
timeFrame: baseline and after 8 weeks of follow up
measure: To evaluate differences in the transmembrane sodium/hydrogen exchanger activity between the active treatment and the control group.
timeFrame: baseline and after 8 weeks of follow up
Other outcomes:
Locations:
city: Thessaloniki
country: Greece
facility: AHEPA University Hospital
Study officials:
affiliation: 1st Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
name: Anastasios N. Lasaridis, MD, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: 1st Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
name: Maria I. Pikilidou, MD, MSc
role: STUDY_DIRECTOR
References: