Article Text

PDF

P90 Vitamin D status improves following recovery from tuberculosis
  1. KD Witt1,
  2. DA Jolliffe1,
  3. Z Wang2,
  4. KE Thummel2,
  5. PM Timms1,
  6. CJ Griffiths1,
  7. AR Martineau1
  1. 1Queen Mary University of London, London, United Kingdom
  2. 2University of Washington, Seattle, USA

Abstract

Introduction and Objectives Vitamin D deficiency associates with active tuberculosis, but the question of whether this arises as a cause or as a consequence of disease is controversial. Paired comparison of vitamin D status of TB patients at diagnosis and following recovery has potential to inform the debate, but such studies have not previously been conducted.

Methods We conducted a longitudinal study comparing serum concentrations of vitamin D metabolites in TB patients at long-term follow-up vs. diagnosis. Participants diagnosed with pulmonary TB in 2007–9 were invited to attend a follow-up visit in 2012. Concentrations of 25-hydroxyvitamin D (25[OH]D, the measure of vitamin D status), 1α,25-dihydroxyvitamin D (1,25[OH]2D), 24R,25-dihydroxyvitamin D (24,25(OH)2D), 4β,25-dihydroxyvitamin D (4,25[OH]2D), calcium, albumin, parathyroid hormone (PTH) and vitamin D binding protein (DBP) were determined in serum samples collected at follow-up and at the time of TB diagnosis. Values at the two time points were compared using Student’s paired t-tests.

Results Thirty-one participants were followed up between August 2012 and February 2013. Serum 25(OH)D concentrations were significantly higher post-recovery than at diagnosis (mean 29.7 vs. 12.2 nmol/L, p < 0.0001). Participants also had higher mean serum concentrations of PTH, corrected calcium and 24,25(OH)2D post-recovery than at diagnosis (PTH, 4.97 vs. 2.78 pmol/L, p = 0.0003; corrected calcium, 2.50 vs. 2.45 mmol/L, p = 0.03; 24,25(OH)2D, 3.15 vs. 1.53 nmol/L, p = 0.004). No statistically significant differences in serum concentrations of 1,25(OH)2D, 4,25(OH)2D or DBP were seen between the two time points. Differences in serum concentrations of 25(OH)D at follow-up vs. baseline remained statistically significant after exclusion of 14 participants who were taking supplemental vitamin D at follow-up and / or who had increased their sun exposure since time of diagnosis (p = 0.005), and after exclusion of 17 participants whose baseline sample was taken from March to July inclusive (p = 0.0003).

Conclusions Vitamin D status of TB patients improved after resolution of tuberculosis. This phenomenon was not explained by differences in vitamin D supplementation, self-reported sun exposure or season of sampling at follow-up vs. baseline. Our findings raise the possibility that vitamin D deficiency may be a consequence, as well as a cause, of active tuberculosis.

Statistics from Altmetric.com

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.