Vitamin D of no benefit in older patients with heart failure?
Researchers from Ninewells Hospital, in Dundee, United Kingdom report no benefit from vitamin D in their patients.
First, the details.
- Participating elderly patients had systolic heart failure, with 25-hydroxyvitamin D levels less than 50 nmol/L (20 ng/mL).
- Normal range is 30 to 74 ng/mL.
- They were randomly assigned to a treatment group.
- 100 000 U of oral vitamin D2 at the start of the study and 10 weeks
- Placebo
- Outcomes measured through 20 weeks were 6-minute walk distance (measures exercise capacity), quality of life, daily activity measured by accelerometry (monitoring human movements), B-type natriuretic peptide (heart stress), and tumor necrosis factor-alpha (inflammation).
- Neither the patients nor researchers knew the treatment given — double blind.
And, the results.
- Participants in the vitamin D group increased their vitamin D levels significantly compared to placebo at 10 weeks (23 vs 2 nmol/L [9 vs 1 ng/mL]) and maintained this increase at 20 weeks.
- The distance walked in 6 minutes didn’t improve in the vitamin D group relative to placebo.
- No significant benefit was seen in function, daily activity, or tumor necrosis factor.
- Quality of life worsened significantly in the treatment group relative to placebo.
- B-type natriuretic peptide decreased significantly in the treatment group relative to placebo (-22 versus +78 pg/mL) at 10 weeks.
The bottom line?
The authors concluded, “Vitamin D supplementation did not improve functional capacity or quality of life in older patients with heart failure with vitamin D insufficiency.”
A valid conclusion considering the objectives of the study. One could argue however, that the vitamin D dose or duration of the study might have affected the results.
It’s interesting that vitamin D supplementation in these elderly patients with heart disease was associated with lower B-type natriuretic peptide. BNP is a well-known marker of dysfunction in the left ventricle and heart failure. Lower levels mean that objectively, these patients experience a beneficial effect on their heart from vitamin D supplementation.
Would following these patients beyond 20 weeks have eventually revealed symptomatic improvement?
3/22/10 18:53 JR