Cynthia Nakasato

Baseline Characteristics and Mortality Among People in Care for Chronic Viral Hepatitis: The Chronic Hepatitis Cohort Study

BACKGROUND The Chronic Hepatitis Cohort Study (CHeCS), a dynamic prospective, longitudinal, observational cohort study, was created to assess the clinical impact of chronic viral hepatitis in the United States. This report describes the cohort selection process, baseline demographics, and insurance, biopsy, hospitalization, and mortality rates. METHODS Electronic health records of >1.6 million adult patients seen from January 2006 through December 2010 at 4 integrated healthcare systems in Detroit, Michigan; Danville, Pennsylvania; Portland, Oregon; and Honolulu, Hawaii were collected and analyzed. RESULTS Of 2202 patients with chronic hepatitis B virus (HBV) infection, 50% were aged 44-63 years, 57% male, 58% Asian/Pacific Islander, and 13% black; and 5.1% had Medicaid, 16.5% Medicare, and 76.3% private insurance. During 2001-2010, 22.3% had a liver biopsy and 37.9% were hospitalized. For the 8810 patients with chronic hepatitis C virus (HCV) infection, 75% were aged 44-63 years, 60% male, 23% black; and 12% had Medicaid, 23% Medicare, and 62% private insurance. During 2001-2010, 38.4% had a liver biopsy and 44.3% were hospitalized. Among persons in care, 9% of persons with HBV and 14% of persons with HCV infection, mainly those born during 1945-1964, died during the 2006-2010 five-year period. CONCLUSIONS Baseline demographic, hospitalization, and mortality data from CHeCS highlight the substantial US health burden from chronic viral hepatitis, particularly among persons born during 1945-1964.

Surgical Outcomes of Total Knee Replacement According to Diabetes Status and Glycemic Control, 2001 to 2009

BACKGROUND Poor glycemic control in patients with diabetes may be associated with adverse surgical outcomes. We sought to determine the association of diabetes status and preoperative glycemic control with several surgical outcomes, including revision arthroplasty and deep infection. METHODS We conducted a retrospective cohort study in five regions of a large integrated health-care organization. Eligible subjects, identified from the Kaiser Permanente Total Joint Replacement Registry, underwent an elective first primary total knee arthroplasty during 2001 through 2009. Data on demographics, diabetes status, preoperative hemoglobin A1c (HbA1c) level, and comorbid conditions were obtained from electronic medical records. Subjects were classified as nondiabetic, diabetic with HbA1c < 7% (controlled diabetes), or diabetic with HbA1c ≥ 7% (uncontrolled diabetes). Outcomes were deep venous thrombosis or pulmonary embolism within ninety days after surgery and revision surgery, deep infection, incident myocardial infarction, and all-cause rehospitalization within one year after surgery. Patients without diabetes were the reference group in all analyses. All models were adjusted for age, sex, body mass index, and Charlson Comorbidity Index. RESULTS Of 40,491 patients who underwent total knee arthroplasty, 7567 (18.7%) had diabetes, 464 (1.1%) underwent revision arthroplasty, and 287 (0.7%) developed a deep infection. Compared with the patients without diabetes, no association between controlled diabetes (HbA1c < 7%) and the risk of revision (odds ratio [OR], 1.32; 95% confidence interval [CI], 0.99 to 1.76), risk of deep infection (OR, 1.31; 95% CI, 0.92 to 1.86), or risk of deep venous thrombosis or pulmonary embolism (OR, 0.84; 95% CI, 0.60 to 1.17) was observed. Similarly, compared with patients without diabetes, no association between uncontrolled diabetes (HbA1c ≥ 7%) and the risk of revision (OR, 1.03; 95% CI, 0.68 to 1.54), risk of deep infection (OR, 0.55; 95% CI 0.29 to 1.06), or risk of deep venous thrombosis or pulmonary embolism (OR, 0.70; 95% CI, 0.43 to 1.13) was observed. CONCLUSIONS No significantly increased risk of revision arthroplasty, deep infection, or deep venous thrombosis was found in patients with diabetes (as defined on the basis of preoperative HbA1c levels and other criteria) compared with patients without diabetes in the study population of patients who underwent elective total knee arthroplasty.

Construction of a Multisite DataLink Using Electronic Health Records for the Identification, Surveillance, Prevention, and Management of Diabetes Mellitus: The SUPREME-DM Project

Introduction Electronic health record (EHR) data enhance opportunities for conducting surveillance of diabetes. The objective of this study was to identify the number of people with diabetes from a diabetes DataLink developed as part of the SUPREME-DM (SUrveillance, PREvention, and ManagEment of Diabetes Mellitus) project, a consortium of 11 integrated health systems that use comprehensive EHR data for research. Methods We identified all members of 11 health care systems who had any enrollment from January 2005 through December 2009. For these members, we searched inpatient and outpatient diagnosis codes, laboratory test results, and pharmaceutical dispensings from January 2000 through December 2009 to create indicator variables that could potentially identify a person with diabetes. Using this information, we estimated the number of people with diabetes and among them, the number of incident cases, defined as indication of diabetes after at least 2 years of continuous health system enrollment. Results The 11 health systems contributed 15,765,529 unique members, of whom 1,085,947 (6.9%) met 1 or more study criteria for diabetes. The nonstandardized proportion meeting study criteria for diabetes ranged from 4.2% to 12.4% across sites. Most members with diabetes (88%) met multiple criteria. Of the members with diabetes, 428,349 (39.4%) were incident cases. Conclusion The SUPREME-DM DataLink is a unique resource that provides an opportunity to conduct comparative effectiveness research, epidemiologic surveillance including longitudinal analyses, and population-based care management studies of people with diabetes. It also provides a useful data source for pragmatic clinical trials of prevention or treatment interventions.

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

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.

The Risk of Immune Thrombocytopenic Purpura After Vaccination in Children and Adolescents

BACKGROUND: The risk of immune thrombocytopenic purpura (ITP) after childhood vaccines other than measles-mumps-rubella vaccine (MMR) is unknown. METHODS: Using data from 5 managed care organizations for 2000 to 2009, we identified a cohort of 1.8 million children ages 6 weeks to 17 years. Potential ITP cases were identified by using diagnostic codes and platelet counts. All cases were verified by chart review. Incidence rate ratios were calculated comparing the risk of ITP in risk (1 to 42 days after vaccination) and control periods. RESULTS: There were 197 chart-confirmed ITP cases out of 1.8 million children in the cohort. There was no elevated risk of ITP after any vaccine in early childhood other than MMR in the 12- to 19-month age group. There was a significantly elevated risk of ITP after hepatitis A vaccine at 7 to 17 years of age, and for varicella vaccine and tetanus-diphtheria-acellular pertussis vaccine at 11 to 17 years of age. For hepatitis A, varicella, and tetanus-diphtheria-acellular pertussis vaccines, elevated risks were based on one to two vaccine-exposed cases. Most cases were acute and mild with no long-term sequelae. CONCLUSIONS: ITP is unlikely after early childhood vaccines other than MMR. Because of the small number of exposed cases and potential confounding, the possible association of ITP with hepatitis A, varicella, and tetanus-diphtheria-acellular pertussis vaccines in older children requires further investigation.

A distributed research network model for post-marketing safety studies: the Meningococcal Vaccine Study.

We describe a multi‐center post‐marketing safety study that uses distributed data methods to minimize the need for covered entities to share protected health information (PHI). Implementation has addressed several issues relevant to creation of a large scale post‐marketing drug safety surveillance system envisioned by the FDAs Sentinel Initiative.

Risk of Guillain-Barré syndrome after meningococcal conjugate vaccination.

A new meningococcal conjugate vaccine (MCV4) was introduced in 2005. Shortly after, case reports of Guillain–Barré syndrome (GBS), a serious demyelinating disease, began to be reported to the Vaccine Adverse Event Reporting System. In 2006, the Centers for Disease Control and Prevention and the Food and Drug Administration requested the evaluation of GBS risk after MCV4 vaccination. We conducted a study to assess the risk of GBS after MCV4 vaccination using health plan administrative and claims data together with the review of primary medical records of potential cases.

Febrile Seizure Risk After Vaccination in Children 6 to 23 Months

BACKGROUND AND OBJECTIVE: An increased risk of febrile seizure (FS) was identified with concomitant administration of trivalent inactivated influenza vaccine (IIV3) and pneumococcal conjugate vaccine (PCV) 13-valent during the 2010–2011 influenza season. Our objective was to determine whether concomitant administration of IIV3 with other vaccines affects the FS risk. METHODS: We examined the risk of FS 0 to 1 day postvaccination for all routinely recommended vaccines among children aged 6 through 23 months during a period encompassing 5 influenza seasons (2006–2007 through 2010–2011). We used a population-based self-controlled risk interval analysis with a control interval of 14 to 20 days postvaccination. We used multivariable regression to control for receipt of concomitant vaccines and test for interaction between vaccines. RESULTS: Only PCV 7-valent had an independent FS risk (incidence rate ratio [IRR], 1.98; 95% confidence interval [CI], 1.00 to 3.91). IIV3 had no independent risk (IRR, 0.46; 95% CI, 0.21 to 1.02), but risk was increased when IIV3 was given with either PCV (IRR, 3.50; 95% CI, 1.13 to 10.85) or a diphtheria-tetanus-acellular-pertussis (DTaP)-containing vaccine (IRR, 3.50; 95% CI, 1.52 to 8.07). The maximum estimated absolute excess risk due to concomitant administration of IIV3, PCV, and DTaP-containing vaccines compared with administration on separate days was 30 FS per 100 000 persons vaccinated. CONCLUSIONS: The administration of IIV3 on the same day as either PCV or a DTaP-containing vaccine was associated with a greater risk of FS than when IIV3 was given on a separate day. The absolute risk of postvaccination FS with these vaccine combinations was small.

Barriers in Identification and Referral to Genetic Counseling for Familial Cancer Risk: The Perspective of Genetic Service Providers

The purpose of this study was to obtain genetic counselors’ perspectives about the identification of appropriate patients and barriers to referral of high-risk patients for cancer genetic counseling services. Genetic service providers from eight integrated health systems were surveyed. Data analysis included descriptive statistics. Twenty-eight of 40 potential participants responded (70%). Referrals for familial cancer risk assessment overwhelmingly came from providers (89%); only 10% were self-referrals. Use of guidelines to assist providers with referral was reported by 46% of the respondents. Genetic service providers perceived patient barriers to seeking genetic counseling after referral included: risk evaluation viewed as a non-priority (72%), concerns about impact on insurability (52%), distance to appointments (48%), lack of insurance (44%), lack of patient/provider knowledge about the value of genetic counseling (36%), discouragement by family members (28%), and fear (20%). The best approaches suggested by respondents to increase appropriate referrals were attending meetings and giving presentations to oncologists, surgeons, primary care and gynecologists. The genetic service providers reported several barriers to the referral and use of genetic counseling. This finding is consistent with current literature from the providers’ perspective. Our survey adds the genetic service providers’ perspective and identifies areas of opportunity for further research and intervention as few of the perceived barriers are being addressed through current educational efforts.

Mortality Rates and Cause-of-Death Patterns in a Vaccinated Population

BACKGROUND Determining the baseline mortality rate in a vaccinated population is necessary to be able to identify any unusual increases in deaths following vaccine administration. Background rates are particularly useful during mass immunization campaigns and in the evaluation of new vaccines. PURPOSE Provide background mortality rates and describe causes of death following vaccination in the Vaccine Safety Datalink (VSD). METHODS Analyses were conducted in 2012. Mortality rates were calculated at 0-1 day, 0-7 days, 0-30 days, and 0-60 days following vaccination for deaths occurring between January 1, 2005, and December 31, 2008. Analyses were stratified by age and gender. Causes of death were examined, and findings were compared to National Center for Health Statistics (NCHS) data. RESULTS Among 13,033,274 vaccinated people, 15,455 deaths occurred between 0 and 60 days following vaccination. The mortality rate within 60 days of a vaccination visit was 442.5 deaths per 100,000 person-years. Rates were highest in the group aged ≥85 years, and increased from the 0-1-day to the 0-60-day interval following vaccination. Eleven of the 15 leading causes of death in the VSD and NCHS overlap in both systems, and the top four causes of death were the same in both systems. CONCLUSIONS VSD mortality rates demonstrate a healthy vaccinee effect, with rates lowest in the days immediately following vaccination, most apparent in the older age groups. The VSD mortality rate is lower than that in the general U.S. population, and the causes of death are similar.