icon-    folder.gif   Conference Reports for NATAP  
  17th CROI
Conference on Retroviruses
and Opportunistic Infections
San Francisco CA
February 16-19, 2010
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High Prevalence of Severe Vitamin D
Deficiency in cART Naïve and Successfully Treated Swiss HIV Patients
  Reported by Jules Levin
17th CROI Feb 16-19 2010 SF
N Muller1*, CA Fux2*, B Ledergerber1, L Elzi3, P Schmid4, T Dang5, L Magenta6, A Calmy7, A Vergopoulos8, H Bischoff-Ferrari9 and the Swiss HIV Cohort Study 1 University Hospital Zurich; 2 University Clinic for Infectious Diseases and University of Berne; 3 University Hospital Basel; 4 Kantonsspital St Gallen; 5 Centre Universitaire Hospitalier Vaudois, Lausanne; 6 Ospedale Civico Lugano; 7 Geneva University Hospital; 8 Institute of Clinical Chemistry, University Hospital Zurich; 9 Centre on Aging and Mobility, University of Zurich; 10 Department of Rheumatology and Institute of Physical Medicine, University Hospital Zurich Switzerland. * contributed equally
With 42-52% in spring and 14-18% in fall vitamin D deficiency was highly prevalent
Black ethnicity was a significant risk factor for vitamin D deficiency
NNRTI-use was associated with significantly lower 25(OH)D levels
TDF-use correlated with higher serum 1,25(OH)2D and serum alkaline phosphatase levels
we suggest systematic screening for vitamin D deficiency in all HIV-positive patients

Recent studies have increased the awareness of beneficial effects of vitamin D. Besides being essential for bone growth and preservation, antineoplastic and immunmodulatory effects have been described.
Considering the high prevalence of osteopenia (up to 60%) and osteoporosis (up to 15%) as well as the increasing number of neoplasias, adequate vitamin D levels seem particularly important in the HIV-population.
To determine vitamin D levels in HIV-positive patients comparing measurements by season as well as before and after the initiation of cART. To look for predictors for vitamin D deficiency
25(OH) vitamin D was measured in 211 HIV-positive patients (Table1).
Samples were taken before initiation of cART from Feb-Apr (nadir sun exposure) or from Aug-Oct (maximal sun exposure) as well as 12 (same season) and 18 months (alternate season) after starting cART.
We defined values <30 nmol/L as vitamin D deficiency,
while 75 nmol/L 25(OH)D was set as minimal target.

1,25(OH)2 vitamin D was measured in a subset of 74 patients.


25(OH) vitamin D

At each timepoint, 25(OH)D levels were significantly higher in fall than in spring (p <0.001), without significant change with respect to cART.
With 42%-52%, vitamin D deficiency was three times more frequent during springtime than in fall.




1,25(OH)2 vitamin D
Correlating the 1,25(OH)2D to 25(OH)D ratio with 25(OH)D levels (below) indicates an exponential increase of 1-hydroxylation (i.e. vitamin D activation) with decreasing 25(OH)D levels. Black circles indicate measurements in fall, white circles in spring. This compensatory increase in renal 1 alpha-hydroxylation with decreasing 25(OH)D levels resulted in a less pronounced seasonal swing for 1,25(OH)2D (minus 3-13%) than for 25(OH)D (minus 36- 43%).