Stable or increasing bone mineral density in HIV-infected patients treated with nelfinavir or indinavir.
OBJECTIVE
To determine the factors contributing to changes in bone mineral density (BMD) over time in HIV-infected patients receiving highly active antiretroviral therapy (HAART).


METHODS
Analyses of lumbar spine BMD in 183 male Caucasian participants in the Western Australian HIV Cohort study, comprising a longitudinal analysis of data from 54 patients on stable HAART regimens, and a cross-sectional analysis comparing data from 131 protease inhibitor (PI)-treated patients and 52 PI-naive (including 28 antiretroviral treatment-naive) patients.


RESULTS
Average lumbar spine BMD remained stable or increased over the time frame considered. Although there was no evidence of a change of average BMD over time in patients receiving nelfinavir (P = 0.92), there was evidence of increasing bone density in the indinavir group (average increase, 0.31 z-score per year; P < 0.001). Lower initial z-scores in the longitudinal analysis were significantly associated with lower pre-HAART BMI (P = 0.003), consistent with results of the cross-sectional analysis in which lowest BMI prior to initial dual X-ray absorptiometry scan was associated with decreased BMD (P = 0.02, overall group). Although PI therapy was also associated with decreased BMD in a univariate analysis of the cross-sectional data (P = 0.04), this effect was abrogated in a multiple linear regression analysis (P = 0.11) with lowest BMI remaining significant (P = 0.04).


CONCLUSIONS
We found no evidence, overall, of accelerated bone loss in patients treated with nelfinavir- or indinavir-containing HAART regimens, and propose that indinavir therapy may be associated with an increase in bone mineral density over time. Pre-HAART BMI was an independent and powerful determinant of an individual's initial z-score in the longitudinal analysis, and adjustment for this effect in a cross-sectional analysis abrogated the association between PI therapy and decreased lumbar spine z-score.
Nolan
D
D
Centre for Clinical Immunology and Biomedical Statistics, Royal Perth Hospital and Murdoch University, Western Australia, Australia.
Upton
R
R
McKinnon
E
E
John
M
M
James
I
I
Adler
B
B
Roff
G
G
Vasikaran
S
S
Mallal
S
S
D015992:Body Mass Index; D015519:Bone Density; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D015658:HIV Infections / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D017320:HIV Protease Inhibitors / Q000627:therapeutic use*; D006321:Heart; D006801:Humans; D019469:Indinavir / Q000627:therapeutic use*; D008137:Longitudinal Studies; D008297:Male; D019888:Nelfinavir / Q000627:therapeutic use*; D015675:Osteocalcin / Q000097:blood
D017320:HIV Protease Inhibitors; D015675:Osteocalcin; D019469:Indinavir; D019888:Nelfinavir