The Effect of Calcium and Vitamin D in Patients With Heart Failure

Study Overview
=================
Brief Summary
-----------------
Previous studies have shown high proportions of vitamin D deficiency among elderly in Denmark. Vitamin D is important for muscular function. The investigators intend to examine if it is possible to improve cardiovascular function in patients with heart failure and vitamin D deficiency by supplementation with vitamin D.

Detailed Description
-----------------
Heart failure (HF) is a major course of morbidity and mortality. The prevalence in the Danish population is 1-2% and for age 50 -75 years: 2-3% (1) . It has been estimated that there are currently 6.5 million HF patients in Europe and 5 million in the USA (2) . Lack of vitamin D has been linked to heart disease including ischemic heart disease, heart failure, and hypertension.(3) Vitamin D deficiency is prevalent in the elderly population. Calcium absorption, bone mineralization and muscle function may be impaired. Vitamin D receptors have also been demonstrated in skeletal as well as cardiac muscle(4) . Vitamin D and Parathyroid Hormone (PTH) are closely linked in the calcium metabolic system. In order to maintain serum calcium within range PTH and vitamin D acts together in response to changes in serum-calcium levels. 25(OH)D concentration also being an important factor determining the levels of PTH.(5) Decreasing vitamin D leads to increasing levels of PTH. Hyperparathyroidism in patients with kidney-disease has in numerous studies been linked to cardiovascular disease, left ventricle hypertrophy, and valvular calcification .(6) Aim: Intervention with vitamin D and calcium will improve patients' vitamin D levels and suppress PTH. Thus we hope to find an improved cardiac function and quality of life in the intervention-group. Comparison: Cardiac function (and other effect parameters - such as self-evaluated health) in the intervention group vs. in the placebo-group

Conditions
-----------------
Heart Failure, Vitamin D Deficiency

Intervention / Treatment
-----------------
* Drug: Vitamin D


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Over 18 years of age Vitamin D (serum 25-OHD): 50nmol/l or less Heart failure (EF 40% or less, NYHA:2 or more) Exclusion Criteria: Calcium metabolic disturbances Granulomatous diseases Alcohol or drug abuse Intake of 400IU (or more) vitamin D/day Condition too poor to participate Pregnancy AF with HF 90 or above Mitral insufficiency, degree 3 or above Large cardiac aneurisms Significant aorta stenosis Significant aorta insufficiency Allergy to components

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1<br>Calcium and vitamin D | Drug: Vitamin D<br>* Daily vitamin D (cholecalciferol) tablets and rocaltrol<br>|
| Placebo Comparator: 2<br>Calcium and placebo (cellulose) | Drug: Vitamin D<br>* Daily vitamin D (cholecalciferol) tablets and rocaltrol<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ejection fraction |  | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 6 minutes walk test | combined skeletal and cardiac muscle function | 6 months | 
| Quality of life | Self assessed health (MLHFQ) | 6 months | 
| Biochemical markers |  | 6 months |