Brian S. Finkelman

Genetic warfarin dosing: tables versus algorithms.

OBJECTIVES The aim of this study was to compare the accuracy of genetic tables and formal pharmacogenetic algorithms for warfarin dosing. BACKGROUND Pharmacogenetic algorithms based on regression equations can predict warfarin dose, but they require detailed mathematical calculations. A simpler alternative, recently added to the warfarin label by the U.S. Food and Drug Administration, is to use genotype-stratified tables to estimate warfarin dose. This table may potentially increase the use of pharmacogenetic warfarin dosing in clinical practice; however, its accuracy has not been quantified. METHODS A retrospective cohort study of 1,378 patients from 3 anticoagulation centers was conducted. Inclusion criteria were stable therapeutic warfarin dose and complete genetic and clinical data. Five dose prediction methods were compared: 2 methods using only clinical information (empiric 5 mg/day dosing and a formal clinical algorithm), 2 genetic tables (the new warfarin label table and a table based on mean dose stratified by genotype), and 1 formal pharmacogenetic algorithm, using both clinical and genetic information. For each method, the proportion of patients whose predicted doses were within 20% of their actual therapeutic doses was determined. Dosing methods were compared using McNemars chi-square test. RESULTS Warfarin dose prediction was significantly more accurate (all p < 0.001) with the pharmacogenetic algorithm (52%) than with all other methods: empiric dosing (37%; odds ratio [OR]: 2.2), clinical algorithm (39%; OR: 2.2), warfarin label (43%; OR: 1.8), and genotype mean dose table (44%; OR: 1.9). CONCLUSIONS Although genetic tables predicted warfarin dose better than empiric dosing, formal pharmacogenetic algorithms were the most accurate.

Incidence of Bladder Cancer in Patients With Type 2 Diabetes Treated With Metformin or Sulfonylureas

OBJECTIVE Previous studies evaluating the effect of metformin on cancer risk have been impacted by time-related biases. To avoid these biases, we examined the incidence of bladder cancer in new users of metformin and sulfonylureas (SUs). RESEARCH DESIGN AND METHODS This cohort study included 87,600 patients with type 2 diabetes in The Health Improvement Network database. Use of metformin or an SU was treated as a time-dependent variable. Cox regression–generated hazard ratios (HRs) compared metformin use with SU use, adjusted for age, sex, smoking, obesity, and HbA1c level. RESULTS We identified 196 incident bladder cancers in the metformin cohort and 66 cancers in the SU cohort. Use of metformin was not associated with decreased bladder cancer risk (HR 0.81 [95% CI 0.60–1.09]). This association did not differ by sex (P for interaction = 0.20). We observed no association with duration of metformin relative to SU use (3 to <4 years of use: 0.57 [0.25–1.34]; 4 to <5 years of use: 0.93 [0.30–2.85; ≥5 years of use: 1.18 [0.44–3.19]; P for trend = 0.26). CONCLUSIONS Use of metformin is not associated with a decreased incidence of bladder cancer. Similar methods should be used to study other cancers that have previously been identified as potentially preventable with metformin.

Clinical Factors Associated with Bacterial Biofilm Formation in Chronic Rhinosinusitis

Objectives. Bacterial biofilms appear to contribute to chronic rhinosinusitis. However, the mechanism behind biofilm formation in chronic rhinosinusitis remains poorly defined. The aim of this study is to evaluate clinical factors that may be associated with bacterial biofilm formation in chronic rhinosinusitis. Study Design. Cross-sectional study. Setting. Department of Otorhinolaryngology–Head and Neck Surgery at the Hospital of the University of Pennsylvania. Subjects and Methods. Five hundred eighteen patients with chronic rhinosinusitis were enrolled from 2007 to 2010. Samples were taken to evaluate for biofilm formation in vitro using a modified Calgary Biofilm Detection Assay. Clinical data were collected from chart review. Pearson’s χ2 and logistic regression were used for the analyses. Results. Of the patients, 108 (20.9%) showed biofilm formation in vitro. Bacterial biofilm formation in vitro was not significantly associated with polyps, allergy, Samter’s triad, sleep apnea, smoking status, age, or gender. However, it was significantly associated with positive culture results (odds ratio [OR] = 3.13; 95% confidence interval [CI], 1.85-5.29; P < .001), prior sinus surgeries (1.93; 1.01-3.69; P = .046), and nasal steroid use in the month prior to sample collection (2.09; 1.07-4.08; P = .030). Polymicrobial cultures, Pseudomonas aeruginosa, and Staphylococcus aureus comprised most of the samples. Conclusion. The results of this study suggest that the probability of bacterial biofilm formation is independent of many clinical factors considered to be risk factors for chronic rhinosinusitis. Further studies are needed to clarify the nature of the associations between prior sinus surgeries, nasal steroid use, and biofilm formation.

New genetic variant that might improve warfarin dose prediction in African Americans

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Variants in the CYP2C9 (i.e. *2 and *3) and VKORC1 (i.e. 1173C/T or -1639G/A) genes have been shown to influence warfarin dose requirements. However, these factors seem to explain less of the dose variability in African Americans who have a lower prevalence of the CYP2C9*2 and *3 and VKORC1 1173T alleles. WHAT THIS STUDY ADDS In African Americans, the VKORC1 rs17886199 variant was statistically significantly associated with log-transformed warfarin maintenance dose, independent of the influence of VKORC1 1173C>T and CYP2C9*2 and *3. However, replication of our finding is needed to confirm the association of rs1786199 SNP in African Americans, since Limdi et al.[3] did not examine the effect of this SNP because the prevalence of the rs1786199 A-allele was too low. AIMS To raise hypotheses with regards to whether genetic variants in the VKORC1, CYP2C9, EPHX1, GGCX and ALB genes might influence warfarin dose in African Americans and Caucasians, independent of the effects of the VKORC1 1173C>T and CYP2C9*2 and *3 variants. METHODS From a prospective cohort study, we obtained additional DNA on 36 Caucasian and 22 African American warfarin users who reached maintenance dose and genotyped them for tagSNPs (r2<0.8) in VKORC1, EPHX1, GGCX and ALB genes, and one exonic CYP2C9 SNP. Linear regression models were fitted to estimate the relationship (P value) between log-transformed maintenance dose and each SNP and the amount of the warfarin dose variability accounted for by each SNP (partial R2). RESULTS In African Americans, the VKORC1 rs17886199 A-allele was associated with a lower dose (GG=46.3 mg and GA=25.6 mg; P=0.002), independent of the VKORC1 1173C>T and CYP2C9*2 and *3 variants. Even after applying Bonferroni correction, the P value would still be considered statistically significant. The VKORC1 rs17886199 variant was not found in Caucasians. In Caucasians, the EPHX1 rs1051741 T-allele was associated with a lower dose (CC=41.3 mg and CT=30.0 mg; P=0.04). The latter was no longer statistically significant after applying Bonferroni correction. CONCLUSIONS Our pilot study suggests that the VKORC1 rs17886199 variant could influence warfarin maintenance dose among African Americans, even after accounting for the influence of the VKORC1 1173C>T variant. Future studies with a larger sample size will be needed to confirm our findings.

Breast and Ovarian Cancer Risk and Risk Reduction in Jewish BRCA1/2 Mutation Carriers

PURPOSE Mutations in BRCA1/2 dramatically increase the risk of both breast and ovarian cancers. Three mutations in these genes (185delAG, 5382insC, and 6174delT) occur at high frequency in Ashkenazi Jews. We evaluated how these common Jewish mutations (CJMs) affect cancer risks and risk reduction. METHODS Our cohort comprised 4,649 women with disease-associated BRCA1/2 mutations from 22 centers in the Prevention and Observation of Surgical End Points Consortium. Of these women, 969 were self-identified Jewish women. Cox proportional hazards models were used to estimate breast and ovarian cancer risks, as well as risk reduction from risk-reducing salpingo-oophorectomy (RRSO), by CJM and self-identified Jewish status. RESULTS Ninety-one percent of Jewish BRCA1/2-positive women carried a CJM. Jewish women were significantly more likely to undergo RRSO than non-Jewish women (54% v 41%, respectively; odds ratio, 1.87; 95% CI, 1.44 to 2.42). Relative risks of cancer varied by CJM, with the relative risk of breast cancer being significantly lower in 6174delT mutation carriers than in non-CJM BRCA2 carriers (hazard ratio, 0.35; 95% CI, 0.18 to 0.69). No significant difference was seen in cancer risk reduction after RRSO among subgroups. CONCLUSION Consistent with previous results, risks for breast and ovarian cancer varied by CJM in BRCA1/2 carriers. In particular, 6174delT carriers had a lower risk of breast cancer. This finding requires additional confirmation in larger prospective and population-based cohort studies before being integrated into clinical care.

Detailed Echocardiographic Phenotyping in Breast Cancer Patients: Associations with Ejection Fraction Decline, Recovery, and Heart Failure Symptoms over 3 Years of Followup.

Background: Cardiovascular disease in patients with breast cancer is of growing concern. The longitudinal effects of commonly used therapies, including doxorubicin and trastuzumab, on cardiac remodeling and function remain unknown in this population. We aimed to define the changes in echocardiographic parameters of structure, function, and ventricular-arterial coupling, and their associations with left ventricular ejection fraction (LVEF) and heart failure symptoms. Methods: In a longitudinal prospective cohort study of 277 breast cancer participants receiving doxorubicin (Dox), trastuzumab (Tras), or both (Dox+Tras), we obtained 1249 echocardiograms over a median follow-up of 2.0 (interquartile range, 1.0–3.0) years. Left ventricular structure, diastolic and contractile function, and ventricular-arterial coupling measures were quantified in a core laboratory blinded to participant characteristics. We evaluated changes in echocardiographic parameters over time, and used repeated-measures regression models to define their association with LVEF decline and recovery. Linear regression models defined the association between early changes in these parameters and subsequent changes in LVEF and heart failure symptoms. Results: Overall, 177 (64%) received Dox, 51 (18%) received Tras, and 49 (18%) received Dox+Tras. With Dox, there was a sustained, modest decrease in LVEF over the follow-up duration (1-year change in LVEF –3.6%; 95% confidence interval [CI], –4.4% to –2.8%; 3-year change –3.8%; 95% CI, –5.1% to –2.5%). With Tras, a similar LVEF decline was observed at 1 year (–4.5%; 95% CI, –6.0% to –2.9%) and 3 years (–2.8%; 95%CI, –5.3 to –0.4%). Participants receiving Dox+Tras demonstrated the greatest declines at 1 year (–6.6%; 95% CI, –8.2 to –5.0%), with partial recovery at 3 years (–2.8%; 95% CI, –4.8 to –0.8%). LVEF declines and recovery were associated primarily with changes in systolic volumes, longitudinal and circumferential strain, and ventricular-arterial coupling indices, effective arterial elastance (Ea) and the coupling ratio Ea/Eessb, without evidence for effect modification across therapies. Early changes in volumes, strain, and Ea/Eessb at 4 to 6 months were associated with 1- and 2-year LVEF changes. Similarly, early changes in strain and Ea were associated with worsening heart failure symptoms at 1 year. Conclusions: Doxorubicin and trastuzumab resulted in modest, persistent declines in LVEF at 3 years. Changes in volumes, strain, and ventricular-arterial coupling were consistently associated with concurrent and subsequent LVEF declines and recovery across therapies. # Clinical Perspective {#article-title-51}Background: Cardiovascular disease in patients with breast cancer is of growing concern. The longitudinal effects of commonly used therapies, including doxorubicin and trastuzumab, on cardiac remodeling and function remain unknown in this population. We aimed to define the changes in echocardiographic parameters of structure, function, and ventricular-arterial coupling, and their associations with left ventricular ejection fraction (LVEF) and heart failure symptoms. Methods: In a longitudinal prospective cohort study of 277 breast cancer participants receiving doxorubicin (Dox), trastuzumab (Tras), or both (Dox+Tras), we obtained 1249 echocardiograms over a median follow-up of 2.0 (interquartile range, 1.0–3.0) years. Left ventricular structure, diastolic and contractile function, and ventricular-arterial coupling measures were quantified in a core laboratory blinded to participant characteristics. We evaluated changes in echocardiographic parameters over time, and used repeated-measures regression models to define their association with LVEF decline and recovery. Linear regression models defined the association between early changes in these parameters and subsequent changes in LVEF and heart failure symptoms. Results: Overall, 177 (64%) received Dox, 51 (18%) received Tras, and 49 (18%) received Dox+Tras. With Dox, there was a sustained, modest decrease in LVEF over the follow-up duration (1-year change in LVEF –3.6%; 95% confidence interval [CI], –4.4% to –2.8%; 3-year change –3.8%; 95% CI, –5.1% to –2.5%). With Tras, a similar LVEF decline was observed at 1 year (–4.5%; 95% CI, –6.0% to –2.9%) and 3 years (–2.8%; 95%CI, –5.3 to –0.4%). Participants receiving Dox+Tras demonstrated the greatest declines at 1 year (–6.6%; 95% CI, –8.2 to –5.0%), with partial recovery at 3 years (–2.8%; 95% CI, –4.8 to –0.8%). LVEF declines and recovery were associated primarily with changes in systolic volumes, longitudinal and circumferential strain, and ventricular-arterial coupling indices, effective arterial elastance (Ea) and the coupling ratio Ea/Eessb, without evidence for effect modification across therapies. Early changes in volumes, strain, and Ea/Eessb at 4 to 6 months were associated with 1- and 2-year LVEF changes. Similarly, early changes in strain and Ea were associated with worsening heart failure symptoms at 1 year. Conclusions: Doxorubicin and trastuzumab resulted in modest, persistent declines in LVEF at 3 years. Changes in volumes, strain, and ventricular-arterial coupling were consistently associated with concurrent and subsequent LVEF declines and recovery across therapies.

Distinguishing incident and prevalent diabetes in an electronic medical records database

To develop a method to identify incident diabetes mellitus (DM) using an electronic medical records (EMR) database and test this classification by comparing incident and prevalent DM with common outcomes related to DM duration.

A Clinical Prediction Model to Assess Risk for Pancreatic Cancer Among Patients With New-Onset Diabetes

BACKGROUND & AIMS Approximately 50% of all patients with pancreatic ductal adenocarcinoma (PDA) develop diabetes mellitus before their cancer diagnosis. Screening individuals with new-onset diabetes might allow earlier diagnosis of PDA. We sought to develop and validate a PDA risk prediction model to identify high-risk individuals among those with new-onset diabetes. METHODS We conducted a retrospective cohort study in a population representative database from the United Kingdom. Individuals with incident diabetes after the age of 35 years and 3 or more years of follow-up after diagnosis of diabetes were eligible for inclusion. Candidate predictors consisted of epidemiologic and clinical characteristics available at the time of diabetes diagnosis. Variables with P values <.25 in the univariable analyses were evaluated using backward stepwise approach. Model discrimination was assessed using receiver operating characteristic curve analysis. Calibration was evaluated using the Hosmer-Lemeshow test. Results were internally validated using a bootstrapping procedure. RESULTS We analyzed data from 109,385 patients with new-onset diabetes. Among them, 390 (0.4%) were diagnosed with PDA within 3 years. The final model (area under the curve, 0.82; 95% confidence interval, 0.75-0.89) included age, body mass index, change in body mass index, smoking, use of proton pump inhibitors, and anti-diabetic medications, as well as levels of hemoglobin A1C, cholesterol, hemoglobin, creatinine, and alkaline phosphatase. Bootstrapping validation showed negligible optimism. If the predicted risk threshold for definitive PDA screening was set at 1% over 3 years, only 6.19% of the new-onset diabetes population would undergo definitive screening, which would identify patients with PDA with 44.7% sensitivity, 94.0% specificity, and a positive predictive value of 2.6%. CONCLUSIONS We developed a risk model based on widely available clinical parameters to help identify patients with new-onset diabetes who might benefit from PDA screening.

Prospective Evaluation of Sunitinib-Induced Cardiotoxicity in Patients with Metastatic Renal Cell Carcinoma

Purpose: To prospectively evaluate cardiotoxicity risk with sunitinib in metastatic renal cell carcinoma (mRCC) routine clinical practice using comprehensive echocardiography and biomarker phenotyping. Experimental Design: In a multicenter prospective study of 90 patients with mRCC, echocardiography and biomarkers of cardiovascular injury and stress were quantified at baseline, 3.5, 15, and 33 weeks following sunitinib initiation. These “on-drug” visits corresponded to cycles 1, 3, and 6, respectively. Left ventricular (LV) dysfunction was defined as an absolute decline in LV ejection fraction (LVEF) by ≥10% to a value of <50%. Conditional survival analyses predicted the risk of LV dysfunction. Linear mixed-effects models estimated changes in LVEF, high-sensitivity Troponin I (hsTnI), and B-type natriuretic peptide (BNP) over time. Results: The predicted risk of LV dysfunction by cycle 6 was 9.7% (95% confidence interval, 3%–17%). The majority of events occurred in the first treatment cycle. This risk diminished to 5% and 2% in patients who had not experienced dysfunction by the completion of cycles 1 and 3, respectively. All evaluable patients who experienced LV dysfunction had subsequent improvement in LVEF with careful management. Six patients (6.7%) developed hsTnI elevations >21.5 pg/mL, and 11 additional patients (12.2%) developed BNP elevations >100 pg/mL. These elevations similarly tended to occur early and resolved over time. Conclusions: On average, patients with mRCC receiving sunitinib exhibit modest declines in LVEF and nonsignificant changes in hsTnI and BNP. However, approximately 9.7% to 18.9% of patients develop more substantive abnormalities. These changes occur early and are largely recoverable with careful management. Clin Cancer Res; 23(14); 3601–9. ©2017 AACR.

Dietary vitamin K intake and anticoagulation control during the initiation phase of warfarin therapy: A prospective cohort study

Dietary vitamin K intake and anticoagulation control during the initiation phase of warfarin therapy: A prospective cohort study -