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