Body fat changes among antiretroviral-naive patients on PI- and NNRTI-based HAART in the Swiss HIV cohort study.
BACKGROUND
Body fat changes are common in patients with HIV. For patients on protease inhibitor (PI)-based highly active antiretroviral therapy (HAART), these changes have been associated with increasing exposure to therapy in general and to stavudine in particular. Our objective is to show whether such associations are more or less likely for patients on non-nucleoside reverse transcriptase inhibitor (NNRTI)-based HAART.


METHODS
We included all antiretroviral-naive patients in the Swiss HIV Cohort Study starting HAART after April 2000 who had had body weight, CD4 cell count and plasma HIV RNA measured between 6 months before and 3 months after starting HAART, and at least one assessment of body fat changes after starting HAART. At visits scheduled every 6 months, fat loss or fat gain is reported by agreement between patient and physician. We estimate the association between reported body fat changes and both time on therapy and time on stavudine, using conditional logistical regression.


RESULTS
Body fat changes were reported for 85 (9%) out of 925 patients at their first assessment; a further 165 had only one assessment. Of the remaining 675 patients, body fat changes were reported for 156 patients at a rate of 13.2 changes per 100 patient-years. Body fat changes are more likely with increasing age [odds ratio (OR) 1.18 (1.00-1.38) per 10 years], with increasing BMI [OR 1.06 (1.01-1.11)] and in those with a lower baseline CD4 cell count [OR 0.91 (0.83-1.01) per 100 cells/microl]. There is only weak evidence that body fat changes are more likely with increasing time on HAART [OR 1.16 (0.93-1.46)]. After adjusting for time on HAART, fat loss is more likely with increasing stavudine use [OR 1.70 (1.34-2.15)]. There is no evidence of an association between reported fat changes and time on NNRTI therapy relative to PI therapy in those patients who used either one therapy or the other [OR 0.98 (0.56-1.63)].


CONCLUSIONS
Fat loss is more likely to be reported with increasing exposure to stavudine. We find no evidence of major differences between PI and NNRTI therapy in the risk of reported body fat changes.
Young
Jim
J
Institut für klinische Epidemiologie, Universitätsspital Basel, Basel, Switzerland. jyoung@uhbs.ch
Rickenbach
Martin
M
Weber
Rainer
R
Furrer
Hansjakob
H
Bernasconi
Enos
E
Hirschel
Bernard
B
Tarr
Philip E
PE
Vernazza
Pietro
P
Battegay
Manuel
M
Bucher
Heiner C
HC
D000273:Adipose Tissue / Q000187:drug effects* / Q000473:pathology*; D000328:Adult; D023241:Antiretroviral Therapy, Highly Active / Q000009:adverse effects; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000473:pathology*; D017320:HIV Protease Inhibitors / Q000009:adverse effects*; D039682:HIV-Associated Lipodystrophy Syndrome / Q000209:etiology / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D018894:Reverse Transcriptase Inhibitors / Q000009:adverse effects*; D012307:Risk Factors; D018119:Stavudine / Q000009:adverse effects; D013557:Switzerland
D017320:HIV Protease Inhibitors; D018894:Reverse Transcriptase Inhibitors; D018119:Stavudine