Prevalence and Risk Factors for Loss of Bone Mineral Density in Male Japanese Patients With HIV

Decreased serum bone specific alkaline phosphatase and increased urinary N-terminal telopeptide of type I collagen as prognostic markers for bone mineral density loss in HIV patients on cART

OBJECTIVES

Bone mineral density (BMD) loss is a major chronic complication in HIV patients. We performed a prospective study to determine the time course of BMD changes and to find prognostic factors of BMD loss in HIV patients on combination antiretroviral therapy (cART).

PATIENTS AND METHODS

Subjects were 54 male Japanese HIV patients who had been on cART ≥1 year with no therapeutic agents for osteoporosis. Patients were observed for ≥1 year (median 3.1 years) and underwent annual BMD analyses using dual energy X-ray absorptiometry. Changes in BMD at lumbar spine and femoral neck were calculated for each person-year of all the patients. Clinical factors were also collected simultaneously with BMD examinations to determine prognostic factors for BMD loss.

RESULTS

In total, 173 person-years in 54 patients were observed. One third (19, 35.2%) and slightly over half (30, 55.6%) patients showed BMD decreases at lumbar spine and femoral neck, respectively. However, the median BMD changes at lumbar spine and femoral neck were 0.0% and -0.52% per year, respectively. Monovariant and mixed model analyses determined that decreased serum bone specific alkaline phosphatase (BAP, p = 0.0047) and increased urinary N-terminal telopeptide (uNTx, p = 0.0011) were prognostic factors for BMD loss at lumbar spine and femoral neck, respectively.

CONCLUSIONS

BMD at both lumbar spine and femoral neck changed little on average in HIV patients on cART. Decreased serum BAP or increased uNTx may be helpful to predict progressive BMD loss in the following year and to select patients for BMD follow-up or initiation of anti-osteoporosis treatment.

Increase of 25-hydroxyvitamin D levels after initiation of combination antiretroviral therapy

Although vitamin D deficiency in HIV patients reported worldwide, the mechanisms and the effect of combination antiretroviral therapy (cART) on vitamin D levels are unclear. Patients were 50 male Japanese with HIV who visited Teikyo University Hospital, Tokyo, Japan. Patients were divided into those receiving cART (cART-experienced group, n = 30) and those who had not received cART (cART-naïve group, n = 20). Patients in the cART-experienced group had received treatment with cART for more than one year and those in the cART-naïve group were just about to start cART at study entry. Patients underwent measurement of serum 25-hydroxyvitamin D (25(OH)D) levels and assessment of clinical factors twice at one year intervals. At study entry, 23 (76.7%) in the cART-experienced group and 19 (95.0%) in the cART-naïve group had vitamin D insufficiency or deficiency. Mean 25(OH)D values were significantly higher in the cART-experienced group (25.2 ng/ml vs. 19.3 ng/ml, p = 0.01). However, levels of 25(OH)D at one year increased more in the cART-naïve group (-1.1 ng/ml vs. 5.0 ng/ml, p = 0.01), with mean 25(OH)D values in the cART-naïve group increasing to match those in the cART-experienced group. HIV infected patients who initiated cART showed increases in vitamin D levels in one year.