The effect of vitamin D level on cardiac rehabilitation in patients with coronary artery disease

Abstract

BACKGROUND:

25-hydroxy vitamin D (25OHD) deficiency is associated with cardiovascular disease and poor physical performance.

OBJECTIVE:

To assign the effect of 25OHD level on cardiac rehabilitation (CR) in patients with coronary artery disease (CAD).

METHODS:

One-hundred-thirty-five patients with CAD who underwent a CR programme were enrolled in this retrospective study. Patients were divided into two-group according to 25OHD level (Group 1: $<$ 20 ng/dl; Group 2: $⩾$ 20 ng/dl). All patients received CR for 30 sessions. Each participant performed 40 minutes of aerobic exercise with a cycloergometer followed by muscle strengthening exercises. The patients were evaluated before and after CR by a pulmonary function test (PFT) and a cardiopulmonary exercise test (CPET).

RESULTS:

There were 77 (57%) patients in Group 1 and 58 patients (43%) in Group 2. Demographic characteristics between the groups were similar. Pre- and post-rehabilitation CPET parameters were lower in Group 1 ( $p<$ 0.05). Both groups had significant improvement in CPET ( $p<$ 0.05). Post-rehabilitation PFT parameters (FEV ${}_1$ , FVC) were higher in Group 2 ( $p<$ 0.05). There was a positive correlation between the 25OHD-level and the CPET-PFT parameters ( $p<$ 0.05).

CONCLUSION:

25OHD deficiency in patients with CAD reduces the response to CR. It also affects respiratory function according to the FEV ${}_1$ , FVC parameters. In patients scheduled for CR, 25OHD-levels should be evaluated, and any deficiency corrected.