Effectiveness of mRNA COVID-19 vaccines and hybrid immunity in preventing SARS-CoV-2 infection and symptomatic COVID-19 among adults in the United States.

Background: Understanding protection against SARS-CoV-2 infection by vaccine and hybrid immunity is important for informing public health strategies as new variants emerge.

Methods: We analyzed data from three cohort studies spanning September 1, 2022-July 31, 2023, to estimate COVID-19 vaccine effectiveness (VE) against SARS-CoV-2 infection and symptomatic COVID-19 among adults with and without prior infection in the United States. Participants collected weekly nasal swabs, irrespective of symptoms, annual blood draws, and completed periodic surveys, which included vaccination status and prior infection history.

Economic Burden of Acute Gastroenteritis among Members of Integrated Healthcare Delivery System, United States, 2014-2016.

We conducted a large surveillance study among members of an integrated healthcare delivery system in Pacific Northwest of the United States to estimate medical costs attributable to medically attended acute gastroenteritis (MAAGE) on the day care was sought and during 30-day follow-up. We used multivariable regression to compare costs of MAAGE and non-MAAGE cases matched on age, gender, and index time. Differences accounted for confounders, including race, ethnicity, and history of chronic underlying conditions.

Health Care Utilization and Clinical Management of All-Cause and Norovirus-Associated Acute Gastroenteritis Within a US Integrated Health Care System.

Background: Norovirus-associated acute gastroenteritis (AGE) exacts a substantial disease burden, yet the health care utilization for and clinical management of norovirus-associated AGE are not well characterized.

Methods: We describe the health care encounters and therapeutics used for patients with all-cause and norovirus-associated AGE in the Kaiser Permanente Northwest health system from 1 April 2014 through 30 September 2016. Medical encounters for patients with AGE were extracted from electronic health records, and encounters within 30 days of one another were grouped into single episodes.

Herpes zoster diagnosis and treatment in relation to incident dementia: A population-based retrospective matched cohort study.

Background: Evidence suggests that some infectious diseases, such as herpes zoster (HZ), are associated with elevated risk of subsequent dementia, while certain anti-viral medications are associated with lower risk. We sought to evaluate associations between HZ diagnosis and treatment with incident dementia in a large, retrospective matched cohort.

Methods: Using ICD-9 and ICD-10 diagnosis codes in electronic medical records, we identified members of Kaiser Permanente Northwest age 50 and older from 2000-2019 with a HZ diagnosis during this period.

Burden of Medically Attended Diarrhea and Outpatient Infection Among Persons in 2 Large Integrated Healthcare Settings, 2016-2021.

Background: Identification of infection (CDI) in the community setting is increasing. We describe testing for CDI among patients with medically attended diarrhea (MAD) in the outpatient setting, and the incidence of outpatient CDI.

Methods: This was a retrospective cohort study among members ≥18 years of age from Kaiser Permanente Southern California and Kaiser Permanente Northwest from 1 January 2016 through 31 December 2021.

Antiviral Treatment and Response are Associated With Lower Risk of Dementia Among Hepatitis C Virus-Infected Patients.

Objective: Eradication of hepatitis C virus (HCV) infection has been linked with improvement in neurocognitive function, but few studies have evaluated the effect of antiviral treatment/ response on risk of dementia. Using data from the Chronic Hepatitis Cohort Study (CHeCS), we investigated how antiviral therapy impacts the risk of developing dementia among patients with HCV.

Methods: A total of 17,485 HCV patients were followed until incidence of dementia, death, or last follow-up.

Real-World Safety and Effectiveness of an 8-Week Regimen of Glecaprevir/Pibrentasvir in Patients with Hepatitis C and Cirrhosis.

Introduction: In 2019, an 8-week regimen of glecaprevir/ pibrentasvir (GLE/PIB) was FDA-approved for treatment of chronic hepatitis C (HCV) in patients with cirrhosis. We used data from the Chronic Hepatitis Cohort Study (CHeCS) to evaluate treatment response and adverse events among patients with HCV and cirrhosis under routine clinical care.

Methods: Using an intention-to-treat (ITT)/modified ITT (mITT) approach, endpoints were (1) sustained virological response (SVR) at 12 weeks (SVR12) post-treatment; and (2) adverse events (AEs)/serious AEs during treatment.

Household Transmission of Viral Acute Gastroenteritis Among Participants Within an Integrated Health Care Delivery System, 2014-2016.

Background: While enteric viruses are highly transmissible, household factors associated with transmission are less well documented. We identified individual- and household-level factors associated with viral acute gastroenteritis (AGE) transmission in a large health care network in the United States.

Methods: Patients presenting with AGE were enrolled from April 2014 to September 2016.

Persistent pruritus associated with worse quality of life in patients with chronic hepatitis.

Introduction: Prevalence and severity of pruritus among US patients with chronic hepatitis B and C (HBV, HCV) are not well-documented. Chronic Hepatitis Cohort Study (CHeCS) patients were surveyed to examine pruritus prevalence and impact on quality of life (QoL).

Methods: Patients who reported experiencing pruritus ≥3 on a Numeric Rating Scale (NRS) within the past 30 days were invited to participate in a 6-month study using the SF-36 questionnaire.

Correlates of healthcare-seeking behavior for acute gastroenteritis-United States, October 1, 2016 -September 30, 2017.

Background: In the United States, public health surveillance systems often underestimate the burden of acute gastroenteritis (AGE) because they only identify disease among those who interact with the healthcare system.

Objective: To identify factors associated with healthcare-seeking behavior among individuals experiencing community-acquired AGE.

Methods: From October 2016 -September 2017, we conducted a weekly, age-stratified, random sample of Kaiser Permanente Northwest members located in northwest Oregon and southwest Washington, United States.

CASCADIA: a prospective community-based study protocol for assessing SARS-CoV-2 vaccine effectiveness in children and adults using a remote nasal swab collection and web-based survey design.

Introduction: Although SARS-CoV-2 vaccines were first approved under Emergency Use Authorization by the Food and Drug Administration in late 2020 for adults, authorisation for young children 6 months to <5 years of age did not occur until 2022. These authorisations were based on clinical trials, understanding real-world vaccine effectiveness (VE) in the setting of emerging variants is critical. The primary goal of this study is to evaluate SARS-CoV-2 VE against infection among children aged >6 months and adults aged <50 years.

Dynamic risk assessment for hepatocellular carcinoma in patients with chronic hepatitis C.

Chronic hepatitis C (HCV) is a primary cause of hepatocellular carcinoma (HCC). Although antiviral treatment reduces risk of HCC, few studies quantify the impact of treatment on long-term risk in the era of direct-acting antivirals (DAA). Using data from the Chronic Hepatitis Cohort Study, we evaluated the impact of treatment type (DAA, interferon-based [IFN], or none) and outcome (sustained virological response [SVR] or treatment failure [TF]) on risk of HCC.

Impact of hepatitis C treatment status on risk of Parkinson's disease and secondary parkinsonism in the era of direct-acting antivirals.

Research suggests a possible link between chronic infection with hepatitis C virus (HCV) and the development of Parkinson's Disease (PD) and secondary Parkinsonism (PKM). We investigated the impact of antiviral treatment status (untreated, interferon [IFN] treated, direct-acting antiviral [DAA] treated) and outcome (treatment failure [TF] or sustained virological response [SVR]) on risk of PD/PKM among patients with HCV. Using data from the Chronic Hepatitis Cohort Study (CHeCS), we applied a discrete time-to-event approach with PD/PKM as the outcome.

Impact of the Early COVID-19 Pandemic on the Number of HIV Preexposure Prophylaxis Uses and the Proportion of Preexposure Prophylaxis Users Receiving Sexually Transmitted Infection Testing Services.

Background: With the potential impact of the COVID-19 pandemic on HIV preexposure prophylaxis (PrEP) care management, we assessed the number of PrEP users and sexually transmitted infection (STI) testing-eligible PrEP users, STI testing rates, and prevalence between prepandemic (January 1, 2018-March 31, 2020) and early-pandemic (April 1, 2020-September 30, 2020) periods.

Methods: In this retrospective cohort study, a PrEP user for a given quarter is defined as either a previous PrEP user or a PrEP initiator who has at least 1-day coverage of tenofovir/emtricitabine in the given quarter. The STI testing-eligible PrEP users for a given quarter were defined as those persons whose runout date (previous dispense date + days of tenofovir/emtricitabine supply) was in the given quarter.

Incidence, Etiology, and Healthcare Utilization for Acute Gastroenteritis in the Community, United States.

Knowledge of the epidemiology of sporadic acute gastroenteritis (AGE) in the United States is limited. During September 2016-September 2017, we surveyed Kaiser Permanente Northwest members in Oregon and Washington, USA, to collect data on the 30-day prevalence of dually defined AGE and diarrhea disease and related health-seeking behavior; from a subset of participants, we obtained a stool specimen. Using the iterative proportional fitting algorithm with raked weights, we generated AGE prevalence and annualized rate estimates.

Sexually Transmitted Infection Testing, Prevalence, and Treatment Among Individuals Receiving HIV Preexposure Prophylaxis Within an Integrated Healthcare Delivery System.

Background: Initial and follow-up sexually transmitted infection (STI) and human immunodeficiency virus (HIV) testing are recommended when taking HIV preexposure prophylaxis (PrEP). We assessed STI services before and after PrEP initiation among persons 18 years or older.

Methods: We conducted this retrospective cohort study at a US integrated healthcare delivery system.

Lower Rates of Emergency Department Visits and Hospitalizations Among Patients With Chronic Hepatitis C With Sustained Virological Response to Interferon-Free Direct-Acting Antiviral Therapy (2014-2018).

We compared rates of emergency department visits and hospitalizations between patients with hepatitis C virus who achieved sustained virological response after direct-acting antiviral therapy (case patients) and matched controls. Among 3049 pairs, case patients demonstrated lower rates of liver-related emergency department visits (P = .01) than controls; all-cause and liver-related hospitalization rates and number of hospitalized days were also lower in case patients (P < .

Incidence of Malignancies Among Patients With Chronic Hepatitis B in US Health Care Organizations, 2006-2018.

Hepatitis B virus (HBV) infection causes hepatocellular carcinoma but its association with other cancers is not well established. We compared age-adjusted incidence of primary cancers among 5773 HBV-infected persons with US cancer registries during 2006-2018. Compared with the US population, substantially higher incidence among HBV-infected persons was observed for hepatocellular carcinoma (standardized rate ratio [SRR], 30.

Laboratory monitoring and antiviral treatment for chronic hepatitis B among routine care patients in the United States.

We investigated factors associated with rates of recommended monitoring of chronic hepatitis B (HBV) patients for viral DNA and alanine aminotransferase (ALT), and initiation of antiviral treatment among eligible patients, in a US cohort of patients under routine care. Patients were categorised by treatment indication: definite, equivocal or ineligible. Baseline covariates included demographics, clinical characteristics and specialist care status.

Dynamic Risk Prediction of Response to Ursodeoxycholic Acid Among Patients with Primary Biliary Cholangitis in the USA.

Background: Ursodeoxycholic acid (UDCA) remains the first-line therapy for primary biliary cholangitis (PBC); however, inadequate treatment response (ITR) is common. The UK-PBC Consortium developed the modified UDCA Response Score (m-URS) to predict ITR (using alkaline phosphatase [ALP] > 1.67 times the upper limit of normal [*ULN]) at 12 months post-UDCA initiation).

Norovirus and Other Viral Causes of Medically Attended Acute Gastroenteritis Across the Age Spectrum: Results from the Medically Attended Acute Gastroenteritis Study in the United States.

Background: Acute gastroenteritis (AGE) causes a substantial burden in the United States, but its etiology frequently remains undetermined. Active surveillance within an integrated healthcare delivery system was used to estimate the prevalence and incidence of medically attended norovirus, rotavirus, sapovirus, and astrovirus.

Methods: Active surveillance was conducted among all enrolled members of Kaiser Permanente Northwest during July 2014-June 2016.

Barriers to family history knowledge and family communication among LGBTQ+ individuals in the context of hereditary cancer risk assessment.

Openness about identity as lesbian, gay, bisexual, transgender, queer, and other sexual orientations and gender identities (LGBTQ+) may cause strain on relationships between family members, which could lead to limited knowledge of cancer family history and reduced communication with family members. As a result, members of the LGBTQ+ community may have more difficulty accessing genetic counseling services for inherited cancer risk. We applied a mixed-methods approach to explore potential barriers to knowledge of cancer family history and family communication among participants of the Cancer Health Assessments Reaching Many (CHARM) study who self-identified as LGBTQ+.

Trends in Cirrhosis and Mortality by Age, Sex, Race, and Antiviral Treatment Status Among US Chronic Hepatitis B Patients (2006-2016).

Background: Changing US demographics and evolving chronic hepatitis B (CHB) treatments may affect longitudinal trends in CHB-related complications. We studied trends in the prevalence of cirrhosis (past or present) and incidence of all-cause mortality, stratified by patient age, sex, race, and antiviral treatment status, in a sample from US health care systems.

Methods: Joinpoint and Poisson regression (univariate and multivariable) were used to estimate the annual percent change in each outcome from 2006 to 2016.

Psychosocial Obstacles to Hepatitis C Treatment Initiation Among Patients in Care: A Hitch in the Cascade of Cure.

There are limited data examining the relationship between psychosocial factors and receipt of direct-acting antiviral (DAA) treatment among patients with hepatitis C in large health care organizations in the United States. We therefore sought to determine whether such factors were associated with DAA initiation. We analyzed data from an extensive psychological, behavioral, and social survey (that incorporated several health-related quality of life assessments) coupled with clinical data from electronic health records of patients with hepatitis C enrolled at four health care organizations during 2017-2018.