Atorvastatin and simvastatin in patients on hemodialysis: effects on lipoproteins, C-reactive protein and in vivo oxidized LDL.

BACKGROUND: Cardiovascular disease as a result of accelerated atherogenesis is common in patients with end-stage renal disease (ESRD). Dyslipidemia may be a major contributor in this process and can be influenced by lipid-lowering drugs (statins). Moreover, statins may exhibit additional inhibitory effects on the atherogenesis, such as a modulation of the immune system as triggered by oxidatively modified LDL and a reduction of the inflammatory marker C-reactive protein (CRP). METHODS: We evaluated in a single-blind randomized trial of 28 ESRD patients on hemodialysis, the dose-depending effects of both atorvastatin and simvastatin on lipids, lipoproteins, LDL particle heterogeneity, high sensitive-CRP, and markers of in vivo LDL oxidation. RESULTS: Both statin therapies significantly lowered total plasma cholesterol and LDL-cholesterol concentrations to the same extent, whereas reduction in the concentrations of triglyceride-rich particles was less pronounced. Furthermore, statin therapy reduced LDL cholesterol in all LDL subfractions, without altering the overall LDL particle density. After both statins plasma hs-CRP concentrations were not significantly reduced; parameters of in vivo LDL oxidation (plasma ox-LDL concentration and the oxidation level of isolated LDL), were significantly decreased. Autoantibodies against ox-LDL, however, did not change during this trial period. CONCLUSIONS: These results show that atorvastatin and simvastatin exhibit comparable favourable effects on lipid profiles in ESRD. Moreover, the reduction of in vivo oxidatively modified LDL as shown in this ESRD population, may indicate that these statins exhibit favourable effects on oxidative stress in vivo.

Assessment of adherence to HIV protease inhibitors: comparison and combination of various methods, including MEMS (electronic monitoring), patient and nurse report, and therapeutic drug monitoring.

BACKGROUND: Adherence to protease inhibitor-containing antiretroviral therapy is crucial, but difficult to measure. OBJECTIVE: To compare and combine various methods of measuring adherence to the strict protease inhibitor-containing regimens. METHODS: The following methods were used: medication event monitoring system (MEMS) caps (electronic monitoring), therapeutic drug monitoring, pill count, pharmacy refill data, questionnaires, diaries (for registration of food patterns and special events related to the use of MEMS), adherence assessment by the physician and clinical nurse specialist, and in-depth interviews. In addition, ultrasensitive viral load and resistance testing was performed. RESULTS: Twenty-eight patients were included; data could be evaluated in 26. According to MEMS data, 25% of the patients took fewer than 95% of all doses, and two thirds of the patients took fewer than 95% of the doses on time. Only 43% of the patients showed good adherence with food restrictions. Methods that showed significant correlations with MEMS results were patients' self-reported adherence; therapeutic drug monitoring, indicating plasma levels outside predefined ranges; and estimation of adherence by a clinical nurse specialist, especially by in-depth interview. CONCLUSION: Diary-corrected MEMS data gave a detailed insight into patients' adherence patterns. Patients' self-report and therapeutic drug monitoring were significantly correlated with the MEMS data, and the clinical nurse specialist may also play a role in identifying patients who are imperfectly adherent.