Comparison of nucleoside reverse transcriptase inhibitor use as part of first-line therapy in a Serbian and a UK HIV clinic.

BACKGROUND: Use of dideoxynucleoside reverse transcriptase inhibitors (dNRTIs) may lead to increased mitochondrial toxicity. We compared nucleoside reverse transcriptase inhibitor (NRTI) use as part of antiretroviral therapy (ART) in two HIV clinics: one in a low-middle income (HIV Centre Belgrade [HCB], Serbia) and one a high income (ICDC, Royal Free Hospital, London, UK) country. METHODS: Antiretroviral naïve patients starting ART from 2003 to 2005 were included. Specific NRTIs were compared between centers, focusing on dNRTI use. Kaplan-Meier estimates of the percentage of patients making changes to their NRTI backbone (a) for any reason or (b) for mitochondrial toxicity (peripheral neuropathy, pancreatitis, lactic acidosis) were calculated. RESULTS: Of 287 HCB patients, 89 (31.0%) received didanosine (ddI)-containing, 39 (13.6%) stavudine (d4T)-containing, and 39 (13.6%) ddI+d4T-containing regimens; for 539 ICDC patients, these were 18 (3.3%), 66 (12.2%), and 0 (0.0%), respectively (p < .0001). After 12 months, 57.5% and 52.6% at HCB and ICDC had switched their NRTI backbone. This was reduced to 34.5% at HCB after excluding changes due to drug supply interruption and to 11.2% and 1.3% at HCB and ICDC after changes were made for mitochondrial-related reasons. At 6 months, 73/80 (91.3%) and 385/488 (78.9%) had viral load below 50 copies/mL at HCB and ICDC, respectively. CONCLUSION: Patients treated at HCB faced higher levels of mitochondrial-related toxicity, likely due to greater dNRTI use.

The metabolic syndrome, an epidemic among HIV-infected patients on HAART.

BACKGROUND: HAART has dramatically changed the prognosis of AIDS, but has led to long-term toxicities of antiretroviral drugs. A major chronic complication is the metabolic syndrome (MS), including hyperlipidemia, lipodystrophy (LD), and impaired glucose metabolism. METHODS: A cross-sectional study of a series of 582 patients from the Serbian HIV/AIDS cohort, treated with HAART for a mean period of 3.3+/-2.1 years (range 1-10), was performed to evaluate the prevalence and risk factors for MS during HAART. RESULTS: The prevalence of LD was 29.1%, with a 100% probability of development after 10 years of treatment. Risk factors for LD included female gender (OR 1.7, 95% CI 1.0-2.7, P=0.02), age>40 (OR 1.7, 95% CI 1.1-2.7, P=0.01) and AIDS at HAART initiation (OR 1.9, 95% CI 1.2-2.2, P<0.01), as well as prolonged usage of NRTIs (OR 2.7, 95% CI 1.6-4.5, P<0.01). The NNRTI-based regimens were less likely to induce LD than those PI-based (OR 1.87, 95% CI 1.2-2.9 vs. OR 3.7, 95% CI 2.3-6.1, respectively). Hyperlipidemia occurred in 47% of the patients, and was associated with male gender (OR 2.2, 95% CI 1.4-3.5, P<0.01) and prolonged usage of PI+NNRTI HAART (OR 3.0, 95% CI 1.8-4.9, P<0.01). In contrast, regimens composed of 2 NRTI+NNRTI were less likely to induce hyperlipidemia (OR 0.4, 95% CI 0.3-0.7, P=0.03). Glucose intolerance and/or diabetes mellitus was recorded in 9.6%, if with AIDS at HAART initiation (OR 3.7, 95% CI 1.2-11.4, P<0.01), male gender (OR 5.2, 95% CI 1.8-15.1, P<0.01) and age>40 (OR 2.6, 95% CI 1.1-6.3, P=0.02). CONCLUSION: MS seems an inevitable consequence of long-term successful HAART.

The prevalence and risk of hepatitis flares in a Serbian cohort of HIV and HCV co-infected patients treated with HAART.

Despite substantial benefits of HAART treatment of HIV-infected patients, cumulative long-term toxicity, including drug-induced hepatotoxicity, has emerged as an important complication. Thus, to examine the prevalence and risk of developing severe hepatic injury during HAART, we conducted a retrospective study in a cohort of 364 HIV-infected patients treated with HAART between January 1998 and May 2006, for whom data on alanine aminotransferase activity were available both before and during HAART. HCV co-infection was recorded in 35.4% of the series, but was found not to influence either the efficacy of HAART or survival (P>0.05). Severe hepatotoxicity occurred in a total of 24 patients (6.6%). Multivariate logistic regression defined HCV co-infection (OR 16.6, 95% CI 3.8-46.0, P<0.0001), and the use of SQV/RTV and d4T (OR 3.1, 95% CI 1.2-8.16, P=0.02, and OR 7.1, 95% CI 1.0-54.5, P=0.05, respectively) as independent risk factors for aggravation of hepatitis. In addition, there was a significant increase in the probability of developing liver damage over years of treatment (Log rank, P<0.01). Conversely, the probability of developing hepatotoxicity was not associated with an increase in the CD4 cell count to values greater than 350/microL (Log rank, P=0.59). In conclusion, in the setting of chronic viral hepatitis, hepatotoxicity during HAART may be attributed to the cumulative toxicity of drugs that induce mitochondrial toxicity, along with particular PIs and/or NNRTIs. Furthermore, our data suggest prudent use of D-drugs, still common in resource-limited countries, in HCV co-infected patients.

Incidence of acute pancreatitis and nucleoside reverse transcriptase inhibitors usage.

Acute pancreatitis (AP) is a well-known adverse effect of nucleoside reverse transcriptase inhibitors (NRTIs). Therefore, we performed a prospective, cohort study to examine the incidence rates (IRs) and rate ratios (RRs) of AP for each NRTI. A total of 116 HIV patients were included in the final analysis comprising 445.6 person-years of follow-up. Twelve cases of AP were recorded. The lowest IR for AP was for didanosine (ddI) (IR=0.03 per 100 person-years, 95% confidence interval [CI] = 0.01-0.05), and the highest for ddI + stavudine (d4T) (IR = 0.08, 95% CI = 0.07-012). Compared with ddI alone, the RR of AP was 2.21 (95% CI = 1.32-9.31) for d4T, and 3.13 (95% CI = 1.43-12.56) for ddI + d4T. Other risk factors for AP were CD4 cell count <200 cells/mm(3) and female sex. Our results suggest that the use of d4T alone or combined with ddI should not be used as first-line therapy, especially in women or patients with CD4-cell count <200 cells/mm(3).