Gowtham A. Rao

Statin Therapy Improves Sustained Virologic Response Among Diabetic Patients With Chronic Hepatitis C

BACKGROUND & AIMS Patients with chronic hepatitis C infection are 2- to 3-fold more likely to develop type 2 diabetes, which reduces their chances of achieving a sustained virologic response (SVR). To identify differences in predictors of SVR in patients with and without diabetes who received combination antiviral therapy, we conducted a retrospective analysis of a national Veterans Affairs administrative database. METHODS We analyzed data from the Veterans Affairs Medical SAS Datasets and Decision Support System for entire cohort and separately for diabetic patients (n = 1704) and nondiabetic patients (n = 6589). Significant predictors of SVR were identified by logistic regression analysis. RESULTS Diabetic patients had a lower SVR compared with nondiabetic patients (21% vs 27%, respectively, P < .001). Diabetic patients had higher clustering of previously established negative predictors of SVR. On multivariate analysis of diabetic patients for SVR, the positive predictors were higher low-density lipoprotein (odds ratio [OR], 1.45; P = .0129), use of statin (OR, 1.52; P = .0124), and lower baseline viral load (OR, 2.31; P < .001), whereas insulin therapy (OR, 0.7; P = .0278) was a negative predictor. Diabetic patients on statins had higher pretreatment viral loads (log 6.2 vs 6.4, respectively, P = .006) but better early virologic response. There was a graded inverse relationship between Hemoglobin A1c and SVR rate (P = .0482). This relationship was significant among insulin users (P = .0154) and non-significant among metformin users (P = .5853). CONCLUSIONS Statin use was associated with an improved SVR among both diabetic patients and nondiabetic patients receiving combination antiviral therapy. Diabetic patients who received insulin achieved lower SVR compared with those not receiving insulin. Poor diabetes control was associated with lower SVR rates.

Azithromycin and Levofloxacin Use and Increased Risk of Cardiac Arrhythmia and Death

PURPOSE Azithromycin use has been associated with increased risk of death among patients at high baseline risk, but not for younger and middle-aged adults. The Food and Drug Administration issued a public warning on azithromycin, including a statement that the risks were similar for levofloxacin. We conducted a retrospective cohort study among US veterans to test the hypothesis that taking azithromycin or levofloxacin would increase the risk of cardiovascular death and cardiac arrhythmia compared with persons taking amoxicillin. METHODS We studied a cohort of US veterans (mean age, 56.8 years) who received an exclusive outpatient dispensation of either amoxicillin (n = 979,380), azithromycin (n = 594,792), or levofloxacin (n = 201,798) at the Department of Veterans Affairs between September 1999 and April 2012. Azithromycin was dispensed mostly for 5 days, whereas amoxicillin and levofloxacin were dispensed mostly for at least 10 days. RESULTS During treatment days 1 to 5, patients receiving azithromycin had significantly increased risk of death (hazard ratio [HR] = 1.48; 95% CI, 1.05–2.09) and serious arrhythmia (HR = 1.77; 95% CI, 1.20–2.62) compared with patients receiving amoxicillin. On treatment days 6 to 10, risks were not statistically different. Compared with patients receiving amoxicillin, patients receiving levofloxacin for days 1 to 5 had a greater risk of death (HR = 2.49, 95% CI, 1.7–3.64) and serious cardiac arrhythmia (HR = 2.43, 95% CI, 1.56–3.79); this risk remained significantly different for days 6 to 10 for both death (HR = 1.95, 95% CI, 1.32–2.88) and arrhythmia (HR = 1.75; 95% CI, 1.09–2.82). CONCLUSIONS Compared with amoxicillin, azithromycin resulted in a statistically significant increase in mortality and arrhythmia risks on days 1 to 5, but not 6 to 10. Levofloxacin, which was predominantly dispensed for a minimum of 10 days, resulted in an increased risk throughout the 10-day period.

Angiotensin receptor blockers: are they related to lung cancer?

Introduction: Angiotensin receptor blockers (ARBs) are commonly used antihypertensive medication with several other additional proven benefits. Recent controversy on association of lung cancer and other solid malignancy with the use of ARBs is concerning, although the follow-up studies have shown no such association. Methods: We used data from the Department of Veterans Affairs electronic medical record system and registries to conduct a retrospective cohort study that compared first-time ARB users with nonusers in 1:15 ratio, after balancing for many baseline differences using inverse probability of treatment weights. We conducted time-to-event survival analyses on the weighted cohort. Results: Of the 1 229 902 patients in the analytic cohort, 346 (0.44%) of the 78 075 treated individuals had a newly incident lung cancer and 6577 (0.57%) of 1 151 826 nontreated individuals were diagnosed with lung cancer. On double robust regression, the weighted hazard ratio was 0.74 (0.67–0.83, P < 0.0001), suggesting a lung cancer reduction effect with ARB use. There was no difference in rates by ARB subtype. Conclusion: In this large nationwide cohort of United States Veterans, we found no evidence to support any concern of increased risk of lung cancer among new users of ARBs compared with nonusers. Our findings were consistent with a protective effect of ARBs.

Predictors of hematological abnormalities in patients with chronic hepatitis C treated with interferon and ribavirin

Hematological abnormalities including neutropenia, anemia, and thrombocytopenia are commonly seen in patients with chronic hepatitis C treated with pegylated interferon and ribavirin. The aim of this study was to identify factors which would help to predict the development of hematological abnormalities in patients with chronic hepatitis C treated with pegylated interferon and ribavirin. During a 4-year period, all patients with chronic hepatitis C started on treatment with pegylated interferon and ribavirin were identified. Patients were defined as having hematological abnormalities if they had the presence of either anemia, neutropenia, thrombocytopenia, or a combination of the above during treatment with pegylated interferon and ribavirin. A total of 136 patients with chronic hepatitis C were included in this study. Fifty-two (38.2%) of the patients developed significant hematological abnormalities during treatment with pegylated interferon and ribavirin with 28 (20.6%), 30 (22.1%), and 11 (8.1%) developed neutropenia, anemia, and thrombocytopenia, respectively. Genotype 1, history of hypertension, low baseline platelet count, low baseline hemoglobin, as well as a raised creatinine were significant factors associated with the development of hematological abnormalities. Significant hematological abnormalities are commonly present in patients with chronic hepatitis C treated with pegylated interferon and ribavirin. This study identifies pretreatment parameters that may help identify high-risk patients who are more likely to develop hematological abnormalities during treatment for chronic hepatitis C.

Cardiac risks associated with antibiotics: azithromycin and levofloxacin

Introduction: Azithromycin and levofloxacin have been shown to be efficacious in treating infections. The adverse drug events associated with azithromycin and levofloxacin were considered rare. However, the US FDA released warnings regarding the possible risk of QT prolongation with azithromycin and levofloxacin. Areas covered: Case reports/case series, observational studies and clinical trials assessing cardiovascular risks associated with azithromycin and levofloxacin were critically reviewed, including 15 case reports/series, 5 observational studies and 5 clinical trials that investigated the cardiac risks associated azithromycin and levofloxacin. Expert opinion: Results are discordant. Two retrospective studies utilizing large databases demonstrated an increased risk of cardiovascular death with azithromycin, when azithromycin was compared with amoxicillin. Two other retrospective studies found no difference in cardiovascular death associated with azithromycin and other antibiotics. For levofloxacin, the increased risk of cardiovascular death was only found in one retrospective study. Therefore, the risks and benefits of antibacterial therapies should be considered when making prescription decisions. This study should not preclude clinicians from avoiding azithromycin and levofloxacin. If a patient has an indication to receive an antibiotic and if azithromycin or levofloxacin is needed, it may be used, but the potential risks must be understood.

Angiotensin Receptor Blockers and Risk of Prostate Cancer Among United States Veterans

To address concerns regarding increased risk of prostate cancer (PrCA) among angiotensin receptor blocker (ARB) users, we used national retrospective data from the Department of Veterans Affairs (VA) through the Veterans Affairs Informatics and Computing Infrastructure. We identified a total of 543,824 unique Veterans who were classified into either ARB treated or not‐treated in 1:15 ratio. The two groups were balanced using inverse probability of treatment weights. A double‐robust cox‐proportional hazards model was used to estimate the hazard ratio for PrCA incidence. To evaluate for a potential Gleason score stage migration, we conducted weighted Cochrane‐Armitage test. Post weighting, the rates of PrCA in treated and not‐treated groups were 506 (1.5%) and 8,269 (1.6%), respectively; representing a hazard ratio of (0.91, p‐value .049). There was no significant difference in Gleason scores between the two groups. We found a small, but statistically significant, reduction in the incidence of clinically detected PrCA among patients assigned to receive ARB with no countervailing effect on degree of differentiation (as indicated by Gleason score). Findings from this study support Food and Drug Administrations recent conclusion that ARB use does not increase risk of incident PrCA.

Systematic Approach to Pharmacovigilance beyond the Limits: The SouthernNetwork on Adverse Reactions (SONAR) Projects

As of 2013, the Southern Network on Adverse Reactions (SONAR) team described 50 significant adverse drug reactions (sADRs) associated with FDA approved drugs. The team also investigates policy issues surrounding pharmacovigilance. Herein we describe the systematic approach to pharmacovigilance taken by the Southern Network on Adverse Reactions and discuss major findings from the group. By 2015, the team hopes to have identified 20 additional sADRs focusing on biologics, biosimilars, and biobetters. The ultimate goal of SONAR is to decrease the timescale between ADR detection and the dissemination of information regarding the sADR

Prostate Specific Antigen-Growth Curve Model to Predict High-Risk Prostate Cancer

To investigate if a prostate specific antigen (PSA)‐derived growth curve can predict the occurrence of high‐risk prostate cancer (PrCA).

The use of multiphase nonlinear mixed models to define and quantify long-term changes in serum prostate-specific antigen: data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

PURPOSE To test the hypothesis that the pattern of prostate-specific antigen (PSA) change in men diagnosed with high-risk prostate cancer (PrCA) differs from the pattern evident in men diagnosed with low-risk PrCA or those with no evidence of PrCA. METHODS A retrospective cohort study from which PSA measures were taken before PrCA diagnosis from the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Data were fitted using a nonlinear regression model to estimate the adjusted absolute and relative (%) change of PSA. RESULTS Data on 20,888 men with an average age of 61.61 years were included in the analysis. Of these, the 324 (1.55%) diagnosed with high-risk PrCA had a steeper and earlier transition into an exponential pattern of PSA change than the 1368 men diagnosed with low-risk cancer. At 1 year before diagnosis and/or exit, the average absolute PSA rates were 0.05 ng/mL/year (0.05-0.05), 0.59 (0.52-0.66), and 2.60 (2.11-3.09) for men with no evidence of PrCA, men with low-risk PrCA and those with high-risk PrCA, respectively. CONCLUSIONS The pattern of PSA change with time was significantly different for men who develop high-risk PrCA from those diagnosed with low-risk PrCA. Further research is required to validate this method and its utilization in PrCA screening.