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Featured researches published by Mark A. Schmidt.


Clinical Infectious Diseases | 2014

Mortality Among Persons in Care With Hepatitis C Virus Infection: The Chronic Hepatitis Cohort Study (CHeCS), 2006–2010

Reena Mahajan; Jian Xing; Stephen J. Liu; Kathleen N. Ly; Anne C. Moorman; Loralee Rupp; Fujie Xu; Scott D. Holmberg; Eyasu H. Teshale; Philip R. Spradling; Stuart C. Gordon; David R. Nerenz; Mei Lu; Lois Lamerato; Loralee B. Rupp; Nonna Akkerman; Nancy Oja-Tebbe; Chad M. Cogan; Dana Larkin; Joseph A. Boscarino; Joe B. Leader; Robert E. Smith; Cynthia Nakasato; Vinutha Vijayadeva; Kelly E. Sylva; John V. Parker; Mark M. Schmidt; Mark A. Schmidt; Judy L. Donald; Erin Keast

BACKGROUND The number of deaths in hepatitis C virus (HCV)-infected persons recorded on US death certificates has been increasing, but actual rates and causes of death in these individuals have not been well elucidated. METHODS Disease-specific, liver-related, and non-liver-related mortality data for HCV-infected patients in an observational cohort study, the Chronic Hepatitis Cohort Study (CHeCS) at 4 US healthcare systems, were compared with multiple cause of death (MCOD) data in 12 million death certificates in 2006-2010. Premortem diagnoses, liver biopsies, and FIB-4 scores (a noninvasive measure of liver damage) were examined. RESULTS Of 2 143 369 adult patients seen at CHeCS sites in 2006-2010, 11 703 (0.5%) had diagnosed chronic HCV infection, and 1590 (14%) died. The majority of CHeCS decedents were born from 1945 to 1965 (75%), white (50%), and male (68%); mean age of death was 59 years, 15 years younger than MCOD deaths. The age-adjusted mortality rate for liver disease in CHeCS was 12 times higher than the MCOD rate. Before death, 63% of decedents had medical record evidence of chronic liver disease, 76% had elevated FIB-4 scores, and, among those biopsied, 70% had moderate or worse liver fibrosis. However, only 19% of all CHeCS decedents and only 30% of those with recorded liver disease had HCV listed on their death certificates. CONCLUSIONS HCV infection is greatly underdocumented on death certificates. The 16 622 persons with HCV listed in 2010 may represent only one-fifth of about 80 000 HCV-infected persons dying that year, at least two-thirds of whom (53 000 patients) would have had premortem indications of chronic liver disease.


Journal of Viral Hepatitis | 2014

APRI and FIB-4 are good predictors of the stage of liver fibrosis in chronic hepatitis B: the Chronic Hepatitis Cohort Study (CHeCS)

Eyasu H. Teshale; M. Lu; Loralee B. Rupp; Scott D. Holmberg; Anne C. Moorman; Philip R. Spradling; Vinutha Vijayadeva; Joseph A. Boscarino; Mark A. Schmidt; Stuart C. Gordon

We aim to determine the predictive ability of APRI, FIB‐4 and AST/ALT ratio for staging of liver fibrosis and to differentiate significant fibrosis (F2–F4) from none to minimal fibrosis (F0–F1) in chronic hepatitis B (CHB). Liver biopsy results were mapped to an F0–4 equivalent fibrosis stage. Mean APRI and FIB‐4 scores were significantly higher for each successive fibrosis level from F1 to F4 (P < 0.05). Based on optimized cut‐offs, the AUROCs in distinguishing F2–F4 from F0 to F1 were 0.81 (0.76–0.87) for APRI, 0.81 (0.75–0.86) for FIB‐4 and 0.56 (0.49–0.64) for AST/ALT ratio. APRI and FIB‐4 distinguished F2–F4 from F0 to F1 with good sensitivity and specificity and can be useful for treatment decisions and monitoring progression of fibrosis.


Hepatology | 2015

Predictors of Poor Mental and Physical Health Status Among Patients With Chronic Hepatitis C Infection: The Chronic Hepatitis Cohort Study (CHeCS)

Joseph A. Boscarino; M. Lu; Anne C. Moorman; Stuart C. Gordon; Loralee B. Rupp; Philip R. Spradling; Eyasu H. Teshale; Mark A. Schmidt; Vinutha Vijayadeva; Scott D. Holmberg

Our objective was to assess the extent and risk factors for depression and poor physical health among patients with chronic hepatitis C virus (HCV) infection. We surveyed HCV‐infected patients seen at four large healthcare systems participating in the Chronic Hepatitis Cohort Study (CHeCS). Survey data included demographics, depression and physical health measures, substance use history, current social support, recent stressor exposures, and, from the electronic medical record, treatment history, and Charlson Comorbidity Index scores. There were 4,781 respondents, who were a mean of 56.7 years old, 71% White, and 57% male. Altogether, 51.4% reported past injection drug use, 33.9% were current smokers, and 17.7% had abused alcohol in the previous year. Additionally, 47.4% had been previously treated for HCV and 14.8% had a 12‐week sustained viral response (SVR) following HCV therapy. Overall, 29.7% of patients met criteria for current depression and 24.6% were in poor physical health. In multivariate analyses, significant predictors of depression and poor health included: male gender (versus female, odds ratios [ORs], 0.70 and 0.81), Black race (versus white, ORs, 0.60 and 0.61), having education less than high school (versus college, ORs, 1.81 and 1.54), being employed (versus not, ORs, 0.36 and 0.25), having high life stressors (versus low, ORs, 2.44 and 1.64), having low social support (versus high, ORs = 2.78 and 1.40), and having high Charlson scores (versus none, ORs = 1.58 and 2.12). Achieving a 12‐week SVR was found to be protective for depression. Conclusion: This large survey of U.S. HCV patients indicates the extent of adverse health behaviors and mental and physical comorbidities among these patients. (Hepatology 2015;61:802–811)


The American Journal of Gastroenterology | 2015

Prevalence of Cirrhosis in Hepatitis C Patients in the Chronic Hepatitis Cohort Study (CHeCS): A Retrospective and Prospective Observational Study

Stuart C. Gordon; Lois Lamerato; Loralee B. Rupp; Scott D. Holmberg; Anne C. Moorman; Philip R. Spradling; Eyasu H. Teshale; Fujie Xu; Joseph A. Boscarino; Vinutha Vijayadeva; Mark A. Schmidt; Nancy Oja-Tebbe; Mei Lu

Objectives:The severity of liver disease in the hepatitis C virus (HCV)-infected population in the United States remains uncertain. We estimated the prevalence of cirrhosis in adults with chronic hepatitis C (CHC) using multiple parameters including liver biopsy, diagnosis/procedure codes, and a biomarker.Methods:Patients enrolled in the Chronic Hepatitis Cohort Study (CHeCS) who received health services during 2006–2010 were included. Cirrhosis was identified through liver biopsy reports, diagnosis/procedure codes for cirrhosis or hepatic decompensation, and Fibrosis-4 (FIB-4) scores ≥5.88. Demographic and clinical characteristics associated with cirrhosis were identified through multivariable logistic modeling.Results:Among 9,783 patients, 2,788 (28.5%) were cirrhotic by at least one method. Biopsy identified cirrhosis in only 661 (7%) patients, whereas FIB-4 scores and diagnosis/procedure codes for cirrhosis and hepatic decompensation identified cirrhosis in 2,194 (22%), 557 (6%), and 482 (5%) patients, respectively. Among 661 patients with biopsy-confirmed cirrhosis, only 356 (54%) had an International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code for cirrhosis. Older age, male gender, Asian race, Hispanic ethnicity, genotype 3 infection, HIV coinfection, diabetes, history of antiviral therapy, and history of alcohol abuse were independently associated with higher odds of cirrhosis (all, P<0.05). Conversely, private health insurance coverage, black race, and HCV genotype 2 were associated with lower odds of cirrhosis.Conclusions:A high proportion of patients with biopsy-confirmed cirrhosis are not assigned ICD-9 codes for cirrhosis. Consequently, ICD-9 codes may not be reliable as the sole indicator of the prevalence of cirrhosis in cohort studies. Use of additional parameters suggests a fourfold higher prevalence of cirrhosis than is revealed by biopsy alone. These findings suggest that cirrhosis in CHC patients may be significantly underdocumented and underdiagnosed.


Hepatology | 2015

Late diagnosis of hepatitis C virus infection in the Chronic Hepatitis Cohort Study (CHeCS): Missed opportunities for intervention.

Anne C. Moorman; Jian Xing; Stephen Ko; Loralee B. Rupp; Fujie Xu; Stuart C. Gordon; M. Lu; Philip R. Spradling; Eyasu H. Teshale; Joseph A. Boscarino; Vinutha Vijayadeva; Mark A. Schmidt; Scott D. Holmberg

To determine the stage of liver disease at initial diagnosis of hepatitis C virus (HCV) infection, we analyzed data from the Chronic Hepatitis Cohort Study (CHeCS), a large U.S. observational study. We examined the temporal relationships of initial HCV infection diagnosis with cirrhosis—defined by liver biopsy or mean FIB‐4 score >5.88—and time to onset of cirrhotic decompensation in electronic medical records. We determined time in the health system prior to HCV diagnosis and rates of hospitalization and death following HCV diagnosis. Of 14,717 patients with chronic HCV seen during 2006‐2011, 6,166 (42%) had a definable time of initial HCV diagnosis. Of these, 1,056 (17%) patients met our definition for “late diagnosis” with either cirrhosis concurrent with initial HCV diagnosis (n = 550), a first diagnosis of hepatic decompensation before or within 12 months after initial HCV diagnosis (n = 506), or both (n = 314). Patients with late diagnosis had an average of 6 years in the health system before their HCV diagnosis. In a comparison with patients without late diagnosis, hospitalization (59% versus 35%) and death (33% versus 9%) were more frequent among patients with late diagnosis. Among all who died, mean (median) time from initial HCV diagnosis to death was 4.8 (4.2) years. Conclusion: Many CHeCS patients had advanced liver disease concurrent with their initial HCV diagnosis despite many years of engagement with the healthcare system, and these patients had high rates of hospitalization and mortality. (Hepatology 2015;61:1479–1484)


PLOS ONE | 2016

Incidence of Norovirus and Other Viral Pathogens That Cause Acute Gastroenteritis (AGE) among Kaiser Permanente Member Populations in the United States, 2012-2013.

Scott P. Grytdal; Emilio E. DeBess; Lore E. Lee; David Blythe; Patricia Ryan; Christianne Biggs; Miriam Cameron; Mark A. Schmidt; Umesh D. Parashar; Aron J. Hall

Noroviruses and other viral pathogens are increasingly recognized as frequent causes of acute gastroenteritis (AGE). However, few laboratory-based data are available on the incidence of AGE caused by viral pathogens in the U.S. This study examined stool specimens submitted for routine clinical diagnostics from patients enrolled in Kaiser Permanente (KP) health plans in metro Portland, OR, and the Maryland, District of Columbia, and northern Virginia geographic areas to estimate the incidence of viral enteropathogens in these populations. Over a one-year study period, participating laboratories randomly selected stools submitted for routine clinical diagnostics for inclusion in the study along with accompanying demographic and clinical data. Selected stools were tested for norovirus, rotavirus, sapovirus, and astrovirus using standardized real-time RT-PCR protocols. Each KP site provided administrative data which were used in conjunction with previously published data on healthcare utilization to extrapolate pathogen detection rates into population-based incidence rates. A total of 1,099 specimens collected during August 2012 to September 2013 were included. Mean age of patients providing stool specimens was 46 years (range: 0–98 years). Noroviruses were the most common viral pathogen identified among patients with AGE (n = 63 specimens, 6% of specimens tested). In addition, 22 (2%) of specimens were positive for rotavirus; 19 (2%) were positive for sapovirus; and 7 (1%) were positive for astrovirus. Incidence of norovirus-associated outpatient visits was 5.6 per 1,000 person-years; incidence of norovirus disease in the community was estimated to be 69.5 per 1,000 person-years. Norovirus incidence was highest among children <5 years of age (outpatient incidence = 25.6 per 1,000 person-years; community incidence = 152.2 per 1,000 person-years), followed by older adults aged >65 years (outpatient incidence = 7.8 per 1,000 person-years; community incidence = 75.8 per 1,000 person-years). Outpatient incidence rates of rotavirus, sapovirus, and astrovirus were 2.0, 1.6, 0.6 per 1,000 person-years, respectively; community incidence rates for these viruses were 23.4, 22.5, and 8.5 per 1,000 person-years, respectively. This study provides the first age-group specific laboratory-based community and outpatient incidence rates for norovirus AGE in the U.S. Norovirus was the most frequently detected viral enteropathogen across the age spectrum with the highest rates of norovirus disease observed among young children and, to a lesser extent, the elderly. These data provide a better understanding of the norovirus disease burden in the United States, including variations within different age groups, which can help inform the development, targeting, and future impacts of interventions, including vaccines.


Journal of Viral Hepatitis | 2016

Hepatitis C treatment failure is associated with increased risk of hepatocellular carcinoma.

M. Lu; Jia Li; Loralee B. Rupp; Scott D. Holmberg; Anne C. Moorman; Philip R. Spradling; Eyasu H. Teshale; Yueren Zhou; Joseph A. Boscarino; Mark A. Schmidt; Lois Lamerato; Connie Mah Trinacty; Sheri Trudeau; Stuart C. Gordon

Sustained virological response (SVR) to antiviral therapy for hepatitis C (HCV) reduces risk of hepatocellular carcinoma (HCC), but there is little information regarding how treatment failure (TF) compares to lack of treatment. We evaluated the impact of treatment status on risk of HCC using data from the Chronic Hepatitis Cohort Study (CHeCS–an observational study based in four large US health systems, with up to 7 years of follow‐up on patients). Multivariable analyses were used to adjust for bias in treatment selection, as well as other covariates, followed by sensitivity analyses. Among 10 091 HCV patients, 3681 (36%) received treatment, 2099 (57%) experienced treatment failure (TF), and 1582 (43%) of these achieved sustained virological response (SVR). TF patients demonstrated almost twice the risk of HCC than untreated patients [adjusted hazard ratio (aHR) = 1.95, 95% confidence interval (CI) 1.50–2.53]; this risk persisted across all stages of fibrosis. Several sensitivity analyses validated these results. Although African Americans were at increased risk of treatment failure, they were at lower risk for HCC and all‐cause mortality compared to White patients. SVR patients had lower risk of HCC than TF patients (aHR = 0.48, CI 0.31–0.73), whereas treatment – regardless of outcome – reduced all‐cause mortality (aHR = 0.45, CI 0.34–0.60 for SVR patients; aHR = 0.78, CI 0.65–0.93 for TF patients).


Journal of Adolescent Health | 2013

Uptake, Coverage, and Completion of Quadrivalent Human Papillomavirus Vaccine in the Vaccine Safety Datalink, July 2006–June 2011

Mark A. Schmidt; Rachel Gold; Samantha Kurosky; Matthew F. Daley; Stephanie A. Irving; Julianne Gee; Allison L. Naleway

PURPOSE The Advisory Committee on Immunization Practices recommended quadrivalent human papillomavirus vaccine (HPV4) for use in females in June 2006 and in males in October 2009. The objective of our study was to describe HPV4 uptake, single-dose coverage, and completion of the three-dose series among those 9-26 years of age, after the respective female and male vaccine licensures through June 2011. METHODS The study population included members of eight managed care organizations participating in the Vaccine Safety Datalink; we abstracted demographic and comprehensive vaccine information from electronic health records. RESULTS We found one-dose coverage increasing throughout the study period, to a high of 37.7% among females and 1.3% among males in June 2011. Among those receiving at least one HPV4 dose, three-dose series completion was 42% for females and 30.2% for males. CONCLUSIONS Our results demonstrate low initiation and completion of the HPV4 series among those recommended to receive the vaccine. Although consistent with previous studies, these results highlight the continued need to develop, implement, and monitor strategies to increase HPV4 vaccine initiation and completion in younger adolescents to achieve maximum impact in reducing the burden of cervical cancer and other HPV-related diseases.


Clinical Infectious Diseases | 2014

Trends in HCV RNA Testing Among HCV Antibody–Positive Persons in Care, 2003–2010

Philip R. Spradling; Xin Tong; Loralee B. Rupp; Anne C. Moorman; Mei Lu; Eyasu H. Teshale; Stuart C. Gordon; Vinutha Vijayadeva; Joseph A. Boscarino; Mark A. Schmidt; Scott D. Holmberg; David R. Nerenz; Lois Lamerato; Nonna Akkerman; Nancy Oja-Tebbe; Chad M. Cogan; Dana Larkin; Joe B. Leader; Robert E. Smith; Kelly E. Sylva; John V. Parker; Mark M. Schmidt; Judy L. Donald; Erin Keast

BACKGROUND A test for hepatitis C virus (HCV) RNA is essential to identify persons with active, or current, HCV infection. We assessed trends in HCV RNA testing following a positive HCV antibody result among persons in 4 large healthcare organizations. METHODS Data collected from adults with ≥2 clinical encounters during 2003-2010 were analyzed to determine the frequency of, interval between, and factors associated with having an RNA test after a first positive HCV antibody test. RESULTS From 2003-2010, 5860 persons had a positive antibody test, of whom 3570 (60.9%) had a follow-up RNA test. During this period, the annual frequency of persons with an eventual RNA test did not change significantly; however, the fraction of persons who had the follow-up RNA test within 6 months improved significantly, from 45% in 2003 to 57% in 2010 (P < .001, for trend). Persons born during 1945-1965, men, and those with annual income <


Journal of Clinical Gastroenterology | 2017

Uptake of and Factors Associated With Direct-acting Antiviral Therapy Among Patients in the Chronic Hepatitis Cohort Study, 2014 to 2015

Philip R. Spradling; Jian Xing; Loralee B. Rupp; Anne C. Moorman; Stuart C. Gordon; Mei Lu; Eyasu H. Teshale; Joseph A. Boscarino; Mark A. Schmidt; Yihe G. Daida; Scott D. Holmberg

30 000 (by census geocode) were less likely to have had a follow-up RNA test done within 6 months of a positive antibody test. CONCLUSIONS Less than two-thirds of persons with a positive HCV antibody test had a follow-up RNA test. Rapid ascertainment of HCV infection status with reflex testing to RNA is critical to identify persons eligible for treatment.

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Anne C. Moorman

Centers for Disease Control and Prevention

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Scott D. Holmberg

Centers for Disease Control and Prevention

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Philip R. Spradling

Centers for Disease Control and Prevention

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Eyasu H. Teshale

Centers for Disease Control and Prevention

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Mei Lu

Henry Ford Health System

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Jia Li

Henry Ford Health System

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