HTB

Bone problems raised in several UK studies

30 August 2008. Related: Conference reports, Side effects, .

Simon Collins, HIV i-Base

Several small studies looked at markers of bone metabolism in patients on HAART.

M Rosenvinge and colleagues from St Georges reported an unexpectedly high rate of vitamin D deficiency in a retrospective case note review of 132 consecutive patients attending their out-patients clinic from November 2007. [1]

They reported 58% patients (76/132) had 25-hydroxycholecalciferol (25(OH)D) deficiency including 8% (11 patients) who were severely deficient (<25nmol/L). A further 27% had borderline deficiency (50-75nmol/L) and only 16% of patients had optimum levels.

Multivariate analysis identified associations with black race (OR 0.14 95%CI 0.02-0.88, white vs black), younger age (OR 0.87, 95%CI 0.78-0.97, for every increase in age by one year) and higher random blood glucose (OR 3.21 95%CI 1.32-7.8 for every increase by 1mmol/L).

No association was found with diagnosis date, CDC stage, use/duration of tenofovir/HAART, weight, kidney/bone profile or parathyroid hormone levels.

Klassen and colleagues from Imperial College reported a case study of severe vitamin D deficiency in a 67 year old Somalian patient who had presented with bone pain, hypophosphatemia (0.64 mmol/L) and raised alkaline phosphatase (>500U/L) while on tenofovir-based HAART. [2]

Vitamin D levels were severely deficient (<15 nmol/L) and she had secondary hyperparathyroidism. Pelvic x-ray was normal.

Vitamin D supplement (dosed 15µg/day) rapidly improved clinical symptoms and normalised phosphate and alkaline phosphatase levels, and Truvada/efavirenz was maintained.

A second poster from this group looked at risk factors for low vitamin D in a group of 79 patients who had been assessed for 25(OH)D levels over a 2-year period. [3]

Mean age of the group was 41 (range 17-72), 70% were on HAART, median CD4 was 380 (range 0-930. 53% were women, 49% were African (33% Caucasian),

Median vitamin D levels were 31 nmol/L (range <15-145). 23% patients had severe deficiency (<25 nmol/L) and 70% has less than optimum levels (25-74 nmol/L). Higher levels were associated with Caucasian origin (P=0.025), current use of HAART (p=0.010) and duration of HAART (p=0.026). CD4 count, season, gender, PI or tenofovir use had no significant association (p>0.064 for all).

S Hill and colleagues from St Mary’s and Hillingdon Hospitals presented an analysis of markers of bone metabolism and the clinical impact in a retrospective review of 205 patients (45% women, 55% black) seen in their cohort during 2007. [4]

From a mean of almost four calcium tests during the year, 42% patients had >1 low calcium level, 23% had >1 low phosphate and 20% had >1 high phosphate.

Low calcium and phosphate levels were more common in patients on HAART and were seen in 47% vs 32% (p=0.06), and 30% vs 5% (p<0.0001) patients, but were not related to tenofovir use. Low vitamin D levels were more common in women than men (8% vs 2%), all of whom were non-Caucasian.

References:

All references are to the Programme and Abstracts of the 14th Annual BHIVA Conference, Dublin, 2008, published as Supplement to HIV Medicine, Volume 9.

  1. Rosenvinge MM et al. Unexpectedly high rates of vitamin D deficiency in an inner-city London HIV clinic. Oral abstract O15.
  2. Klassen K et al. Vitamin D deficiency presenting with hypophosphatemia, bone pain and a raised alkaline phosphatase in a patient on tenofovir. Poster P83.
  3. Klassen K et al. Risk factors for hypovitaminosis D in HIV-positive individuals. Poster P95A.
  4. Hill S et al. How common are abnormalities of serum calcium, phosphate and vitamin D in an HIV-positive cohort and what is their clinical significance. Poster 96.

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