Cardiovascular Risk and Health Among People With HIV Eligible for Primary Prevention: Insights From the REPRIEVE Trial

Background

In addition to traditional cardiovascular (CV) risk factors, antiretroviral therapy, lifestyle, and human immunodeficiency virus (HIV)-related factors may contribute to future CV events in persons with HIV (PWH).

Methods

Among participants in the global REPRIEVE randomized trial, we characterized demographics and HIV characteristics relative to ACC/AHA pooled cohort equations (PCE) for atherosclerotic CV disease predicted risk and CV health evaluated by Life’s Simple 7 (LS7; includes smoking, diet, physical activity, body mass index, blood pressure, total cholesterol, and glucose).

Results

Among 7382 REPRIEVE participants (31% women, 45% Black), the median PCE risk score was 4.5% (lower and upper quartiles Q1, Q3: 2.2, 7.2); 29% had a PCE score <2.5%, and 9% scored above 10%. PCE score was related closely to known CV risk factors and modestly (<1% difference in risk score) to immune function and HIV parameters. The median LS7 score was 9 (Q1, Q3: 7, 10) of a possible 14. Only 24 participants (0.3%) had 7/7 ideal components, and 36% had ≤2 ideal components; 90% had <5 ideal components. The distribution of LS7 did not vary by age or natal sex, although ideal health was more common in low sociodemographic index countries and among Asians. Poor dietary and physical activity patterns on LS7 were seen across all PCE scores, including the lowest risk categories.

Conclusions

Poor CV health by LS7 was common among REPRIEVE participants, regardless of PCE. This suggests a critical and independent role for lifestyle interventions in conjunction with conventional treatment to improve CV outcomes in PWH.

Clinical Trials Registration: NCT02344290.

AIDS Clinical Trials Group study number: A5332.

Assessment of Coronary Artery Disease With Computed Tomography Angiography and Inflammatory and Immune Activation Biomarkers Among Adults With HIV Eligible for Primary Cardiovascular Prevention

IMPORTANCE

Cardiovascular disease (CVD) is increased among people with HIV (PWH), but little is known regarding the prevalence and extent of coronary artery disease (CAD) and associated biological factors in PWH with low to moderate traditional CVD risk.

OBJECTIVES

To determine unique factors associated with CVD in PWH and to assess CAD by coronary computed tomography angiography (CTA) and critical pathways of arterial inflammation and immune activation.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study among male and female PWH, aged 40 to 75 years, without known CVD, receiving stable antiretroviral therapy, and with low to moderate atherosclerotic cardiovascular disease (ASCVD) risk according to the 2013 American College of Cardiology/American Heart Association pooled cohort equation, was part of the Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE), a large, ongoing primary prevention trial of statin therapy among PWH conducted at 31 US sites. Participants were enrolled from May 2015 to February 2018. Data analysis was conducted from May to December 2020.

EXPOSURE

HIV disease.

MAIN OUTCOMES AND MEASURES

The primary outcome was the prevalence and composition of CAD assessed by coronary CTA and, secondarily, the association of CAD with traditional risk indices and circulating biomarkers, including insulin, monocyte chemoattractant protein 1 (MCP-1), interleukin (IL) 6, soluble CD14 (sCD14), sCD163, lipoprotein-associated phospholipase A2 (LpPLA2), oxidized low-density lipoprotein (oxLDL), and high-sensitivity C-reactive protein (hsCRP).

RESULTS

The sample included 755 participants, with a mean (SD) age of 51 (6) years, 124 (16%) female participants, 267 (35%) Black or African American participants, 182 (24%) Latinx participants, a low median (interquartile range) ASCVD risk (4.5% [2.6%-6.8%]), and well-controlled viremia. Overall, plaque was seen in 368 participants (49%), including among 52 of 175 participants (30%) with atherosclerotic CVD (ASCVD) risk of less than 2.5%. Luminal obstruction of at least 50% was rare (25 [3%]), but vulnerable plaque and high Leaman score (ie, >5) were more frequently observed (172 of 755 [23%] and 118 of 743 [16%], respectively). Overall, 251 of 718 participants (35%) demonstrated coronary artery calcium score scores greater than 0. IL-6, LpPLA2, oxLDL, and MCP-1 levels were higher in those with plaque compared with those without (eg, median [IQR] IL-6 level, 1.71 [1.05-3.04] pg/mL vs 1.45 [0.96-2.60] pg/mL; P = .008). LpPLA2 and IL-6 levels were associated with plaque in adjusted modeling, independent of traditional risk indices and HIV parameters (eg, IL-6: adjusted odds ratio, 1.07; 95% CI, 1.02-1.12; P = .01).

CONCLUSIONS AND RELEVANCE

In this study of a large primary prevention cohort of individuals with well-controlled HIV and low to moderate ASCVD risk, CAD, including noncalcified, nonobstructive, and vulnerable plaque, was highly prevalent. Participants with plaque demonstrated higher levels of immune activation and arterial inflammation, independent of traditional ASCVD risk and HIV parameters.

Patterns of Antiretroviral Therapy Use and Immunologic Profiles at Enrollment in the REPRIEVE Trial

BACKGROUND

Patterns of antiretroviral therapy (ART) use and immunologic correlates vary globally, and contemporary trends are not well described.

METHODS

The REPRIEVE trial (Randomized Trial to Prevent Vascular Events in HIV) enrolled persons with human immunodeficiency virus (HIV) who were aged 40-75 years, receiving ART, and had low-to-moderate cardiovascular disease risk. ART use was summarized within Global Burden of Disease (GBD) super-regions, with adjusted linear and logistic regression analyses examining associations with immune parameters and key demographics.

RESULTS

A total of 7770 participants were enrolled, with a median age of 50 years (interquartile range, 45-55 years); 31% were female, 43% were black or African American, 15% were Asian, 56% had a body mass index >25 (calculated as weight in kilograms divided by height in meters squared), and 49% were current or former smokers. The median CD4 T-cell count was 620/µL (interquartile range, 447-826/ µ L), and the median duration of prior ART use, 9.5 years (5.3-14.8) years. The most common ART regimens were nucleoside/nucleotide reverse-transcriptase inhibitor (NRTI) plus nonnucleoside reverse-transcriptase inhibitor (43%), NRTI plus integrase strand transfer inhibitor (25%), and NRTI plus protease inhibitor (19%). Entry ART varied by GBD region, with shifts during the trial enrollment period. In adjusted analyses, entry CD4 cell count and CD4/CD8 ratio were associated with GBD region, sex, entry regimen, duration of ART, and nadir CD4 cell count; CD4 and CD8 cell counts were also associated with body mass index and smoking status.

CONCLUSIONS

There were substantial variations in ART use by geographic region and over time, likely reflecting the local availability of specific medications, changes in treatment guidelines and provider/patient preferences. The analyses of CD4 cell counts and CD4/CD8 ratios may provide valuable insights regarding immune correlates and outcomes in people living with HIV.

CLINICAL TRIALS REGISTRATION

NCT02344290.

Differential Plasma Protein Regulation and Statin Effects in Human Immunodeficiency Virus (HIV)-Infected and Non-HIV-Infected Patients Utilizing a Proteomics Approach

BACKGROUND

People with human immunodeficiency virus (PWH) demonstrate increased atherosclerotic cardiovascular disease (ASCVD). Statins are being studied to prevent ASCVD in human immunodeficiency virus (HIV), but little is known regarding the effects of statins on a broad range of inflammatory and cardiovascular proteins in this population.

METHODS

We used a highly specific discovery proteomic approach (Protein Extension Assay), to determine statin effects on over 350 plasma proteins in relevant ASCVD pathways among HIV and non-HIV groups. Responses to pitavastatin calcium were assessed in 89 PWH in the INTREPID trial and 46 non-HIV participants with features of central adiposity and insulin resistance. History of cardiovascular disease was exclusionary for both studies.

RESULTS

Among participants with HIV, PCOLCE (enzymatic cleavage of type I procollagen) significantly increased after pitavastatin therapy and PLA2G7 (systemic marker of arterial inflammation) decreased. Among participants without HIV, integrin subunit alpha M (integrin adhesive function) and defensin alpha-1 (neutrophil function) increased after pitavastatin therapy and PLA2G7 decreased. At baseline, comparing participants with and without HIV, differentially expressed proteins included proteins involved in platelet and endothelial function and immune activation.

CONCLUSIONS

Pitavastatin affected proteins important to platelet and endothelial function and immune activation, and effects differed to a degree within PWH and participants without HIV.

Successful recruitment of a multi-site international randomized placebo-controlled trial in people with HIV with attention to diversity of race and ethnicity: critical role of central coordination

Background: The Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE) is a multicenter, randomized, placebo-controlled trial, designed to test whether a statin medication can prevent cardiovascular disease in people with HIV. REPRIEVE recently completed enrollment of 7557 participants at over 100 clinical sites globally. Participant groups of focus were women, and racial and ethnic minorities.Objective: To describe recruitment methods and strategies developed by the REPRIEVE Clinical Coordinating Center (CCC) and share best practices learned from the recruitment process.Methods: Enrollment targets were agreed upon with the primary funder, the National Heart, Lung, and Blood Institute (NHLBI) and were milestone driven. Milestones included number of sites activated, number of participants enrolled within specific time frames, and proportion of women and minorities enrolled. Strategies to achieve these milestones included structured interviews with site-designated REPRIEVE Recruitment Champions to develop best practices, development of a multimedia campaign, and site level recruitment support.Results: Recruitment initiated March, 2015 and completed March, 2019. The final accrual target was 7500 participants over 48 months. The trial met this target within the time specified. Overall, 10,613 screens were completed, 48% of participants enrolled from sites outside of North America, 32% were female, 44% were Black or African American, and 25% were Hispanic or Latino.Conclusions: REPRIEVE met its overall projected recruitment goal by using multiple, simultaneous strategies to specifically target a diverse population including minority subgroups. REPRIEVE benefited from the development of recruitment strategies with clear targets and communication of accrual targets to study teams.

Rationale and design of the Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE)

BACKGROUND

Cardiovascular disease (CVD) is more frequent among people with HIV (PWH) and may relate to traditional and nontraditional factors, including inflammation and immune activation. A critical need exists to develop effective strategies to prevent CVD in this population.

METHODS

The Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE) (A5332) is a prospective, randomized, placebo-controlled trial of a statin strategy for the primary prevention of major adverse cardiovascular events (MACE) in PWH with low to moderate traditional risk. At least 7,500 PWH, 40-75 years of age, on stable antiretroviral therapy, will be randomized to pitavastatin calcium (4 mg/d) or identical placebo and followed for up to 8 years. Participants are enrolled based on the 2013 American College of Cardiology (ACC)/American Heart Association (AHA) atherosclerotic cardiovascular disease (ASCVD) risk score and low-density lipoprotein cholesterol (LDL-C) level with a goal to identify a low- to moderate-risk population who might benefit from a pharmacologic CVD prevention strategy. Potential participants with a risk score ≤ 15% were eligible based on decreasing LDL-C thresholds for increasing risk score >7.5% (LDL-C <190 mg/dL for risk score <7.5%, LDL-C <160 mg/dL for risk score 7.6%-10%, and LDL-C<130 mg/dL for risk score 10.1%-15%). The primary objective is to determine effects on a composite end point of MACE. Formal and independent adjudication of clinical events will occur using standardized criteria. Key secondary end points include effects on MACE components, all-cause mortality, specified non-CVD events, AIDS and non-AIDS events, and safety.

RESULTS

To date, REPRIEVE has enrolled >7,500 participants at approximately 120 sites across 11 countries, generating a diverse and representative population of PWH to investigate the primary objective of the trial.

CONCLUSIONS

REPRIEVE is the first trial investigating a primary CVD prevention strategy in PWH. REPRIEVE will inform the field of the efficacy and safety of a statin strategy among HIV-infected participants on antiretroviral therapy and provide critical information on CVD mechanisms and non-CVD events in PWH.

Effects of Pitavastatin on Insulin Sensitivity and Liver Fat: A Randomized Clinical Trial

Context

3-Hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) are widely prescribed. Statins may have important metabolic effects on insulin sensitivity and liver fat, but limited studies have assessed these effects by using euglycemic hyperinsulinemic clamp, stable isotopes, and 1H magnetic resonance spectroscopy (MRS) for liver fat quantification.

Objective

To study the effects of pitavastatin on hepatic fat and insulin sensitivity.

Design

Six-month, double-blind, randomized, placebo-controlled trial.

Setting

Academic clinical research center in Boston, Massachusetts.

Participants

Overweight, insulin-resistant men aged 40 to 65 years who had not received statin therapy for ≥1 year.

Interventions

Pitavastatin 4 mg or placebo daily.

Outcome

The primary endpoints were changes in insulin sensitivity measured by euglycemic hyperinsulinemic clamp and liver fat measured by 1H MRS.

Results

Pitavastatin showed no effect on endogenous glucose production (ΔRa glucose 0.07 ± 0.07 vs 0.04 ± 0.07 mg/kg/min, pitavastatin vs placebo, P = 0.76) or insulin-stimulated glucose uptake during "low dose" (ΔM 0.1 ± 0.1 vs -0.3 ± 0.2 mg/kg/min, P = 0.11) and "high dose" (ΔM -0.5 ± 0.3 vs -0.7 ± 0.4 mg/kg/min, P = 0.70) euglycemic hyperinsulinemic clamps. There was also no effect of pitavastatin on fasting glucose, HbA1c, and 2-hour glucose after 75-g glucose challenge. There was also no change in liver fat fraction (-1 ± 1 vs -0 ± 1%, P = 0.56).

Conclusion

Compared with placebo, pitavastatin did not affect hepatic or whole-body insulin sensitivity, and it did not reduce liver fat.

Assessing statin effects on cardiovascular pathways in HIV using a novel proteomics approach: Analysis of data from INTREPID, a randomized controlled trial

Background

People with HIV (PWH) demonstrate increased cardiovascular disease (CVD), due in part to increased immune activation, inflammation, and endothelial dysfunction.

Methods

In a randomized trial (INTREPID), 252 HIV-infected participants with dyslipidemia and no history of coronary artery disease were randomized (1:1) to pitavastatin 4 mg vs. pravastatin 40 mg for 52 weeks. Using a proteomic discovery approach, 92 proteins biomarkers were assessed using Proximity Extension Assay technology to determine the effects of statins on key atherosclerosis and CVD pathways among PWH. 225 participants had specimens available for biomarker analysis pre- and post-baseline.

Findings

The mean age was 49.5 ± 8.0 (mean ± SD), LDL-C 155 ± 25 mg/dl and CD4 count 620 ± 243 cell/mm³. Among all participants, three proteins significantly decreased: tissue factor pathway inhibitor [TFPI; t-statistic = −6.38, FDR p-value<0.0001], paraoxonase 3 [PON3; t-statistic = −4.64, FDR p-value = 0.0003], and LDL-receptor [LDLR; t-statistic = −4.45, FDR p-value = 0.0004]; and two proteins significantly increased galectin-4 [Gal-4; t-statistic = 3.50, FDR p-value = 0.01] and insulin-like growth factor binding protein 2 [IGFBP-2; t-statistic = 3.21, FDR p-value = 0.03]. The change in TFPI was significantly different between the pitavastatin and pravastatin groups. Among all participants, change in TFPI related to the change in LDL-C (r = 0.43, P < 0.0001) and change in Lp-PLA2 (r = 0.29, P < 0.0001).

Interpretation

Using a proteomics approach, we demonstrated that statins led to a significant reduction in the levels of TFPI, PON3, and LDLR and an increase in Gal-4 and IGFBP-2, key proteins involved in coagulation, redox signaling, oxidative stress, and glucose metabolism. Pitavastatin led to a greater reduction in TFPI than pravastatin. These data highlight potential novel mechanisms of statin effects among PWH.

Fund

This work was supported by an investigator-initiated grant to S.K.G. from KOWA Pharmaceuticals America, Inc. and the National Institutes of Health [P30 DK040561; Nutrition Obesity Research Center at Harvard]. M.T. was support by National Institutes of Health [5KL2TR001100-05; Harvard Catalyst KL2 grant].

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Among PWH, statins significantly decreased three proteins [tissue factor pathway inhibitor (TFPI), paraoxonase 3 (PON3), and LDL-receptor (LDLR)].

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Among PWH, statins significantly increased galectin-4 (Gal-4) and insulin-like growth factor binding protein 2 (IGFBP-2).

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The proteins significantly affected by statin therapy are involved in important pathways in atherosclerosis and cardiovascular disease.

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The change in TFPI was directly related to the change in LDL-C and a systemic marker of arterial inflammation (Lp-PLA2).

Gender differences in side effects and attitudes regarding statin use in the Understanding Statin Use in America and Gaps in Patient Education (USAGE) study

BACKGROUND

Statin therapy has been shown to reduce cardiovascular morbidity and mortality, and the benefits of statin therapy are similar for men and women. Recent studies have shown that women are less likely to be treated with statin therapy, to be on higher doses of more potent statins, and to achieve their lipid goals as compared with men.

OBJECTIVES

To analyze results from the Understanding Statin Use in America and Gaps in Patient Education (USAGE) survey and to assess whether women differ from men with regard to reported side effects associated with statin use, clinician and patient interactions, as well as general attitudes and preferences regarding statin use.

METHODS

The study population was derived from participants in the USAGE survey, a self-administered, Internet-based questionnaire.

RESULTS

More women reported switching or stopping a statin because of side effects compared with men. New or worsening muscle symptoms were reported in 31% of women compared with 26% of men (P < .01). More women, including high-risk women reported that their doctor did not give them information about their risk for heart disease compared with men. Women were more likely to try 3 or more statins, but less likely to use alternative low-density lipoprotein cholesterol-lowering drugs. Women were more likely to be dissatisfied with their statin, with how their clinician explained their cholesterol treatment, and less adherent to their statin than men.

CONCLUSIONS

Women are more likely to stop or switch their statin than men, and the main reason for this was new or worsening muscle symptoms. Improved communication between the clinician and the patient about the benefits and risks of statin therapy will improve adherence, lipid goal attainment, and outcomes in women with or at risk for cardiovascular disease.

Pitavastatin 4 mg Provides Significantly Greater Reduction in Remnant Lipoprotein Cholesterol Compared With Pravastatin 40 mg: Results from the Short-term Phase IV PREVAIL US Trial in Patients With Primary Hyperlipidemia or Mixed Dyslipidemia

PURPOSE

Remnants are partially hydrolyzed, triglyceride-rich lipoproteins that are implicated in atherosclerosis. We assessed the adequacy of pitavastatin 4 mg and pravastatin 40 mg in reducing atherogenic lipid parameters beyond LDL-C, in particular remnant lipoprotein cholesterol (RLP-C).

METHODS

From the Phase IV, multicenter, randomized, double-blind PREVAIL US (A Study of Pitavastatin 4 mg Vs. Pravastatin 40 mg in Patients With Primary Hyperlipidemia or Mixed Dyslipidemia) trial, we examined lipoprotein cholesterol subfractions using Vertical Auto Profile testing and apolipoproteins B and A-I at baseline and 12 weeks. Participants with primary hyperlipidemia or mixed dyslipidemia had LDL-C levels of 130 to 220 mg/dL and triglyceride levels ≤ 400 mg/dL. In this post hoc analysis, changes in lipid parameters were compared by using ANCOVA.

FINDINGS

Lipoprotein subfraction data were available in 312 patients (pitavastatin, n = 157; pravastatin, n = 155). Pitavastatin promoted a greater reduction in RLP-C than pravastatin (-13.6 [8.7] vs -9.3 [9.5] mg/dL). Furthermore, the pitavastatin group reported greater reductions in both components of RLP-C (both, P < 0.001): intermediate-density lipoprotein cholesterol (-9.5 [6.3] vs -6.4 [6.6] mg/dL) and very low-density lipoprotein cholesterol subfraction 3 (-4.1 [3.5] vs -2.9 [3.8] mg/dL). There were also greater reductions in the major ratios of risk (apolipoprotein B/apolipoprotein A-I and total cholesterol/HDL-C) (both, P < 0.001). There were no significant changes in HDL-C, its subfractions, or natural log lipoprotein(a)-cholesterol. The mean age was 58.8 ± 8.9 years in the pitavastatin group and 57.0 ± 10.2 years in the pravastatin group.

IMPLICATIONS

Compared with pravastatin 40 mg daily, pitavastatin 4 mg provided superior reductions in atherogenic lipid parameters beyond LDL-C, including RLP-C. Future studies are needed investigate the clinical implications of lowering directly measured RLP-C as the principal target. ClinicalTrials.gov identifier: NCT01256476.

Effect of high-dose pitavastatin on glucose homeostasis in patients at elevated risk of new-onset diabetes: insights from the CAPITAIN and PREVAIL-US studies

AIMS

Statin treatment may impair glucose homeostasis and increase the risk of new-onset diabetes mellitus, although this may depend on the statin, dose and patient population. We evaluated the effects of pitavastatin 4 mg/day on glucose homeostasis in patients with metabolic syndrome in the CAPITAIN trial. Findings were validated in a subset of patients enrolled in PREVAIL-US.

METHODS

Participants with a well defined metabolic syndrome phenotype were recruited to CAPITAIN to reduce the influence of confounding factors. Validation and comparison datasets were selected comprising phenotypically similar subsets of individuals enrolled in PREVAIL-US and treated with pitavastatin or pravastatin, respectively. Mean change from baseline in parameters of glucose homeostasis (fasting plasma glucose [FPG], glycated hemoglobin [HbA1c], insulin, quantitative insulin-sensitivity check index [QUICKI] and homeostasis model of assessment-insulin resistance [HOMA-IR]) and plasma lipid profile were assessed at 6 months (CAPITAIN) and 3 months (PREVAIL-US) after initiating treatment.

RESULTS

In CAPITAIN (n = 12), no significant differences from baseline in HbA1c, insulin, HOMA-IR and QUICKI were observed at day 180 in patients treated with pitavastatin. A small (4%) increase in FPG from baseline to day 180 (P < 0.05), was observed. In the validation dataset (n = 9), no significant differences from baseline in glycemic parameters were observed at day 84 (all comparisons P > 0.05). Similar results were observed for pravastatin in the comparison dataset (n = 14).

CONCLUSIONS

Other than a small change in FPG in the CAPITAIN study, neutral effects of pitavastatin on glucose homeostasis were observed in two cohorts of patients with metabolic syndrome, independent of its efficacy in reducing levels of atherogenic lipoproteins. The small number of patients and relatively short follow-up period represent limitations of the study. Nevertheless, these data suggest that statin-induced diabetogenesis may not represent a class effect.

Factors associated with statin selection among privately insured commercial and Medicare patients

OBJECTIVES

Given the availability of several statins in the United States, it is important to understand patient characteristics associated with their initiation. We analyzed demographic and clinical factors associated with statin selection among new statin users.

METHODS

This retrospective cohort study examined factors associated with statin selection among patients newly initiated on therapy between 1/1/2007 and 12/31/2007. Commercial and Medicare patient cohorts were evaluated separately and comparisons were made between pravastatin (PS) and other statins including simvastatin (SS), atorvastatin (AS), or rosuvastatin (RS). Multiple logistic regression models were employed to assess factors associated with PS initiation versus other statins.

RESULTS

In commercially insured patients, patients initiating PS were more likely to be older, female, and have diabetes mellitus, liver dysfunction, human immunodeficiency virus (HIV) infection, or hypertension and use calcium channel blockers, protease inhibitors, or additional lipid-modifying agents (p < 0.01 for each comparison). In Medicare-age patients, a higher percentage of PS initiators were aged 75-85, female, had atrial fibrillation, and were prescribed warfarin or triazole antifungals (p < 0.01 for each comparison). Presence of atrial fibrillation or HIV infection, or use of calcium channel blockers or additional lipid-modifying agents was associated with PS initiation compared with AS and SS. Use of warfarin was significantly associated with initiating PS compared with SS, AS, and RS in Medicare-age patients.

CONCLUSION

Older age and female gender were associated with PS initiation. In addition, selected comorbidities and use of certain medications including warfarin or protease inhibitors were associated with PS initiation, which may reflect the tolerability of PS and its reduced risk of significant drug-drug interactions for certain patients. Because this study is a retrospective analysis of US healthcare claims, the findings are limited to only those factors captured within claims data and may not be generalizable to all patient populations in which statin therapy is initiated.

Effect of pitavastatin vs. rosuvastatin on international normalized ratio in healthy volunteers on steady-state warfarin

OBJECTIVE

Statins have been shown to impact international normalized ratio (INR) when coadministered with warfarin. The aim of this study was to assess the effect of pitavastatin compared with rosuvastatin on steady-state pharmacodynamics (PD) of warfarin by measuring INR in healthy adult subjects.

METHODS

Subjects received oral doses of warfarin 5 mg once daily on days 1 through 3. The dose was titrated on days 4 through 9 to reach a steady-state INR of 1.5 to 2.2. Warfarin was continued on days 10 through 21 and pitavastatin 4 mg or rosuvastatin 40 mg was administered once daily on days 14 through 22. After a 14-day washout period, the process was repeated with the alternate statin. STUDY NUMBER: NK-104-4.03US.

RESULTS

For pitavastatin, mean INR changed from 1.73 ± 0.18 (n = 42) on day 14 before starting statin dosing, to 1.78 ± 0.29 (n = 42) on day 22 at treatment end; the difference in INR was not significant (p = 0.219). For rosuvastatin, mean INR increased significantly from 1.74 ± 0.20 (n = 43) at baseline to 1.90 ± 0.30 (n = 43) at treatment end (p < 0.001). Rosuvastatin caused a significantly greater increase in INR than pitavastatin (p < 0.001).

CONCLUSION

Steady-state INR during warfarin treatment did not change significantly when pitavastatin 4 mg was added to the regimen, while a significant increase was observed when rosuvastatin 40 mg was added. The effect of rosuvastatin on INR was significantly larger than the effect of pitavastatin. This study is limited because it was done in healthy volunteers. Further studies in patient populations are needed to better understand the clinical significance of the results.

Interim results of a pilot study demonstrating the early effects of the PPAR-gamma ligand rosiglitazone on insulin sensitivity, aminotransferases, hepatic steatosis and body weight in patients with non-alcoholic steatohepatitis

BACKGROUND/AIMS

Hyperinsulinemia may cause hepatic steatosis and non-alcoholic steatohepatitis (NASH). The aims of this pilot study were to examine the safety of using the insulin-sensitizing peroxisomal proliferator activated receptor (PPAR) gamma ligand rosiglitazone in patients with NASH and determine whether improved insulin sensitivity correlates with improved fatty liver.

METHODS

Thirty subjects with NASH and elevated alanine aminotransferase (ALT) levels received rosiglitazone, 4 mg twice daily for 48 weeks; the preliminary results presented here were obtained at 24 weeks. Insulin sensitivity was measured using fasting insulin and glucose levels and liver fat content was estimated by CT imaging.

RESULTS

By 24 weeks, rosiglitazone improved insulin sensitivity and reduced liver fat content. The mean ALT decreased from 86 to 37 U/l (P<0.01). Four subjects (13%) withdrew, one because of a rise in ALT from 59 to 277 U/l that coincided with concomitant prednisone use. Subjects experienced a mean weight gain of 3.5% and hemoglobin drop of 1.1 g/dl.

CONCLUSIONS

Treatment of NASH with rosiglitazone for 24 weeks improved insulin sensitivity, reduced liver fat content and improved biochemical evidence of hepatocellular injury. These preliminary data provide evidence that hyperinsulinemia may be a cause of NASH. Strategies to improve insulin sensitivity as a treatment of NASH deserve further investigation.

Treatment of hepatitis B and C following liver transplantation

Advanced liver disease from hepatitis B virus (HBV) and hepatitis C virus (HCV) is the leading indication for orthotopic liver transplantation (OLT) worldwide. Our understanding of recurrent liver disease related to HBV and HCV in the setting of OLT has evolved rapidly in the past decade. Recurrent viral hepatitis may lead to graft failure, death, or the need for retransplantation. Until about a decade ago, HBV was considered a contraindication to OLT due to its frequent recurrence and development of associated liver disease. Medical therapy with hepatitis B immune globulin and nucleoside analogues has diminished the risk of HBV recurrence and led to improvement in patient and graft survival. Consequently, OLT is now considered to be the standard of care in patients with end-stage liver disease related to HBV. HCV recurrence after OLT is almost universal. Although short-term survival in patients undergoing OLT for HCV is similar to survival for those transplanted for other indications, recurrent HCV may have an impact on long-term patient and graft survival. A specific and effective therapy has not been defined for recurrent HCV following transplantation, but the combination of interferon and ribavirin appears promising. Optimal strategies to eradicate these viruses or to slow disease progression are continually being investigated in light of the disparity between supply and demand in a diminishing organ pool for OLT candidates.

Clinical improvement in patients with decompensated liver disease caused by hepatitis B after treatment with lamivudine

Lamivudine is effective in inhibiting hepatitis B virus (HBV) replication, and its clinical use in patients with chronic hepatitis B is associated with improvements in serum aminotransferase levels and liver histopathologic characteristics. Few data are available on its use in patients with advanced liver disease. We report on the outcomes of 5 patients with hepatic decompensation caused by chronic hepatitis B treated long term with lamivudine. All patients were adult white men seropositive for hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) before therapy. All 5 patients had biopsy-proven cirrhosis with clinical and biochemical evidence of hepatic decompensation. Two patients had Child's class C cirrhosis; 2 patients, class B; and 1 patient, class A (although this patient had persistent portasystemic encephalopathy and developed variceal bleeding). HBV DNA became undetectable in all patients and remained so throughout the study. Both patients with Child's class C and 1 patient with class B cirrhosis had significant clinical improvement. Child-Pugh scores improved from 12 to 7 and 11 to 7 in the 2 patients with Child's class C cirrhosis, and the patient with class B cirrhosis had complete resolution of troublesome encephalopathy. Serum aminotransferase, albumin, and total bilirubin levels improved significantly in 3 of 5 patients. One patient with Child's class B cirrhosis underwent orthotopic liver transplantation at week 13 after dramatic increases in liver tests and clinical worsening. The patient subsequently cleared HBeAg and HBsAg from serum posttransplantation. In conclusion, prolonged therapy with lamivudine resulted in improved serum biochemical values and loss of HBV DNA in patients with decompensated cirrhosis. Clinical improvements, reflected in Child-Pugh classification and functional status, may also occur, particularly among those with Child's class C disease initially.

Sensitivity of human glioma and brain cells to natural killer cell lysis. Effects of serum concentration, epidermal growth factor, and time in culture

Using an in vitro monolayer natural killer (NK) cytolysis assay, the authors examined the effects of serum concentration and epidermal growth factor (EGF) on sensitivity to NK cytolysis. It was found that target cells cultured in high concentrations of serum (10% fetal bovine serum (FBS)) had higher cytotoxicity levels than those in low serum concentrations (0% to 0.5% FBS). Exposure of target cells to EGF had no effect on their sensitivity to NK cytolysis. Both glioma cell lines showed decreased NK cell sensitivity with longer times in culture. The results of cytofluorometric studies on these cell lines indicate that the differences in NK cell sensitivity may reflect the growth fraction of the target population and that a population with a higher proportion of cycling cells is more susceptible to lysis by NK cells. Whether it is possible to separate the proliferative rate of these cells from their NK cell sensitivity is unknown, but worthy of consideration.