Relative contribution of COVID-19 vaccination and SARS-CoV-2 infection to population-level seroprevalence of SARS-CoV-2 spike antibodies in a large integrated health system.

Background: Understanding the relative contributions of SARS-CoV-2 infection-induced and vaccine- induced seroprevalence is key to measuring overall population-level seroprevalence and help guide policy decisions. Methods: Using a series of six population-based cross-sectional surveys conducted among persons aged ≥7 years in a large health system with over 4.5 million members between May 2021 and April 2022, we combined data from the electronic health record (EHR), an electronic survey and SARS-CoV-2 spike antibody binding assay, to assess the relative contributions of infection and vaccination to population- level SARS-CoV-2 seroprevalence. EHR and survey data were incorporated to determine spike antibody positivity due to SARS-CoV-2 infection and COVID-19 vaccination. We used sampling and non-response weighting to create population-level estimates. Results: We enrolled 4,319 persons over six recruitment waves. SARS-CoV-2 spike antibody seroprevalence increased from 83.3% (CI 77.0-88.9) in May 2021 to 93.5% (CI 89.5-97.5) in April 2022. By April 2022, 68.5% (CI 61.9-74.3) of the population was seropositive from COVID-19 vaccination only, 13.9% (10.7-17.9) from COVID-19 vaccination and prior diagnosed SARS-CoV-2 infection, 8.2% (CI 4.5- 14.5) from prior diagnosed SARS-CoV-2 infection only and 2.9% (CI 1.1-7.6) from prior undiagnosed SARS-CoV-2 infection only. We found high agreement (≥97%) between EHR and survey data for ascertaining COVID-19 vaccination and SARS-CoV-2 infection status. Conclusions: By April 2022, 93.5% of persons had detectable SARS-CoV-2 spike antibody, predominantly from COVID-19 vaccination. In this highly vaccinated population and over 18 months into the pandemic, SARS-CoV-2 infection without COVID-19 vaccination was a small contributor to overall population-level seroprevalence. Article summary: By April 2022, >93% of people had antibodies to SARS-CoV-2 with COVID-19 vaccination as the main driver of overall population-level seroprevalence in our healthcare system. SARS-CoV-2 infection without vaccination made a small contribution to population-level seroprevalence in our healthcare system.

Natural History of Multiple Recurrences in Intermediate-Risk Non-Muscle Invasive Bladder Cancer: Lessons From a Prospective Cohort.

OBJECTIVE: To describe the risk of multiple recurrences in intermediate-risk non-muscle invasive bladder cancer (IR-NMIBC) and their impact on progression. Prognostic studies of IR-NMIBC have focused on initial recurrences, yet little is known about subsequent recurrences and their impact on progression. MATERIALS AND METHODS: IR-NMIBC patients from the Be-Well Study, a prospective cohort study of NMIBC patients diagnosed from 2015 to 2019 at Kaiser Permanente Northern California, were identified. The frequency of first, second, and third intravesical recurrences of urothelial carcinoma were characterized using conditional Kaplan-Meier analyses and random-effects shared-frailty models. The association of multiple recurrences with progression was examined. RESULTS: In 291 patients with IR-NMIBC (median follow-up 38 months), the 5-year risk of initial recurrence was 54.4%. After initial recurrence (n = 137), 60.1% of patients had a second recurrence by 2 years. After second recurrence (n = 70), 51.5% of patients had a third recurrence by 3 years. In multivariable analysis, female sex (Hazard Ratio 1.51, P< .01), increasing tumor size (HR 1.14, P< .01) and number of prior recurrences (HR 1.24, P< .01) were associated with multiple recurrences; whereas maintenance BCG (HR 0.66, P = .03) was associated with reduced recurrences. The 5-year risk of progression varied significantly (P< .01) by number of recurrences: 9.5%, 21.9%, and 37.9% for patients with 1, 2, and 3+ recurrences, respectively. CONCLUSIONS: Multiple recurrences are common in IR-NMIBC and are associated with progression. Female sex, larger tumors, number of prior recurrences, and lack of maintenance BCG were associated with multiple recurrences. Multiple recurrences may prove useful as a clinical trial endpoint for IR-NMIBC.

Quantifying cancer risk from exposures to medical imaging in the Risk of Pediatric and Adolescent Cancer Associated with Medical Imaging (RIC) Study: research methods and cohort profile.

PURPOSE: The Risk of Pediatric and Adolescent Cancer Associated with Medical Imaging (RIC) Study is quantifying the association between cumulative radiation exposure from fetal and/or childhood medical imaging and subsequent cancer risk. This manuscript describes the study cohorts and research methods. METHODS: The RIC Study is a longitudinal study of children in two retrospective cohorts from 6 U.S. healthcare systems and from Ontario, Canada over the period 1995-2017. The fetal-exposure cohort includes children whose mothers were enrolled in the healthcare system during their entire pregnancy and followed to age 20. The childhood-exposure cohort includes children born into the system and followed while continuously enrolled. Imaging utilization was determined using administrative data. Computed tomography (CT) parameters were collected to estimate individualized patient organ dosimetry. Organ dose libraries for average exposures were constructed for radiography, fluoroscopy, and angiography, while diagnostic radiopharmaceutical biokinetic models were applied to estimate organ doses received in nuclear medicine procedures. Cancers were ascertained from local and state/provincial cancer registry linkages. RESULTS: The fetal-exposure cohort includes 3,474,000 children among whom 6,606 cancers (2394 leukemias) were diagnosed over 37,659,582 person-years; 0.5% had in utero exposure to CT, 4.0% radiography, 0.5% fluoroscopy, 0.04% angiography, 0.2% nuclear medicine. The childhood-exposure cohort includes 3,724,632 children in whom 6,358 cancers (2,372 leukemias) were diagnosed over 36,190,027 person-years; 5.9% were exposed to CT, 61.1% radiography, 6.0% fluoroscopy, 0.4% angiography, 1.5% nuclear medicine. CONCLUSION: The RIC Study is poised to be the largest study addressing risk of childhood and adolescent cancer associated with ionizing radiation from medical imaging, estimated with individualized patient organ dosimetry.

History of Early Childhood Infections and Acute Lymphoblastic Leukemia Risk Among Children in a US Integrated Health-Care System.

Surrogate measures of infectious exposures have been consistently associated with lower childhood acute lymphoblastic leukemia (ALL) risk. However, recent reports have suggested that physician-diagnosed early-life infections increase ALL risk, thereby raising the possibility that stronger responses to infections might promote risk. We examined whether medically diagnosed infections were related to childhood ALL risk in an integrated health-care system in the United States. Cases of ALL (n = 435) diagnosed between 1994-2014 among children aged 0-14 years, along with matched controls (n = 2,170), were identified at Kaiser Permanente Northern California. Conditional logistic regression was used to estimate risk of ALL associated with history of infections during first year of life and across the lifetime (up to diagnosis). History of infection during first year of life was not associated with ALL risk (odds ratio (OR) = 0.85, 95% confidence interval (CI): 0.60, 1.21). However, infections with at least 1 medication prescribed (i.e., more "severe" infections) were inversely associated with risk (OR = 0.42, 95% CI: 0.20, 0.88). Similar associations were observed when the exposure window was expanded to include medication-prescribed infections throughout the subjects' lifetime (OR = 0.52, 95% CI: 0.32, 0.85).

A Scalable Database of Organ Doses for Common Diagnostic Fluoroscopy Procedures of Children: Procedures of Historical Practice for Use in Radiation Epidemiology Studies.

Assessment of health effects from low-dose radiation exposures in patients undergoing diagnostic imaging is an active area of research. High-quality dosimetry information pertaining to these medical exposures is generally not readily available to clinicians or epidemiologists studying radiation-related health risks. The purpose of this study was to provide methods for organ dose estimation in pediatric patients undergoing four common diagnostic fluoroscopy procedures: the upper gastrointestinal (UGI) series, the lower gastrointestinal (LGI) series, the voiding cystourethrogram (VCUG) and the modified barium swallow (MBS). Abstracted X-ray film data and physician interviews were combined to generate procedure outlines detailing X-ray beam projections, imaged anatomy, length of X-ray exposure, and presence and amount of contrast within imaged anatomy. Monte Carlo radiation transport simulations were completed for each of the four diagnostic fluoroscopy procedures across the 162-member (87 males and 75 females) University of Florida/National Cancer Institute pediatric phantom library, which covers variations in both subject height and weight. Absorbed doses to 28 organs, including the active marrow and bone endosteum, were assigned for all 162 phantoms by procedure. Additionally, we provide dose coefficients (DCs) in a series of supplementary tables. The DCs give organ doses normalized to procedure-specific dose metrics, including: air kerma-area product (µGy/mGy · cm2), air kerma at the reference point (µGy/µGy), number of spot films (SF) (µGy/number of SFs) and total fluoroscopy time (µGy/s). Organs accumulating the highest absorbed doses per procedure were as follows: kidneys between 0.9-25.4 mGy, 1.1-16.6 mGy and 1.1-9.7 mGy for the UGI, LGI and VCUG procedures, respectively, and salivary glands between 0.2-3.7 mGy for the MBS procedure. Average values of detriment-weighted dose, a phantom-specific surrogate for the effective dose based on ICRP Publication 103 tissue-weighting factors, were 0.98 mSv, 1.16 mSv, 0.83 mSv and 0.15 mSv for the UGI, LGI, VCUG and MBS procedures, respectively. Scalable database of organ dose coefficients by patient sex, height and weight, and by procedure exposure time, reference point air kerma, kerma-area product or number of spot films, allows clinicians and researchers to compute organ absorbed doses based on their institution-specific and patient-specific dose metrics. In addition to informing on patient dosimetry, this work has the potential to facilitate exposure assessments in epidemiological studies designed to investigate radiation-related risks.

Recovering from Cystectomy: Patient Perspectives.

BACKGROUND: Bladder cancer patients who undergo cystectomy and urinary diversion face functional and quality-of-life challenges. Little is known about these patients' experiences during decision-making, surgery, and recovery, or how they vary by treatment setting. OBJECTIVE: To learn about patients' experiences with treatment choice, surgical care, and recovery across health settings. Understanding patient experiences is essential to closing care gaps and developing patient-reported measures. METHODS: We conducted focus groups with cystectomy patients and family caregivers at a large comprehensive health care system (N = 32 patients) and an NCI-designated comprehensive cancer center (N = 25 patients and 5 caregivers). Using standard qualitative methods, we identified themes that are not well-represented in existing research. RESULTS: Across both systems, patients described variable experiences in decision-making about their cystectomy and urinary diversion. Some felt overwhelmed by information; others felt poorly informed. Many found self-care equipment challenging; many felt they knew little about what to expect regarding chemotherapy, recovery, and transitioning home. At times, health care personnel could not help manage patients' ostomies or catheterization equipment. Our study also contributes a grounded theoretical framework for describing meaningful domains of patient experience with cystectomy and urinary diversion. We identified a common trajectory that includes decision-making, surgery and post-operative recovery, mastery of self-care, and reintegration. CONCLUSIONS: Patients with radical cystectomy and urinary diversion report a wide variety of experiences not captured by quantitative measures. These findings demonstrate that many cystectomy patients could benefit from additional post-operative support. We offer a framework to measure patient-centered domains in future research.

Factors That Influence Selectionof Urinary Diversion Among Bladder Cancer Patients in 3 Community-based Integrated Health Care Systems.

OBJECTIVE: To assess the relative contributions of patient and surgeon factors for predicting selection of ileal conduit (IC), neobladder (NB), or continent pouch (CP) urinary diversions (UD) for patients diagnosed with muscle-invasive/high-risk nonmuscle invasive bladder cancer. This information is needed to enhance research comparing cancer survivors' outcomes across different surgical treatment options. METHODS: Bladder cancer patients' age ≥21 years with cystectomy/UD performed from January 2010 to June 2015 in 3 Kaiser Permanente regions were included. All patient and surgeon data were obtained from electronic health records. A mixed effects logistic regression model was used treating surgeon as a random effect and region as a fixed effect. RESULTS: Of 991 eligible patients, 794 (80%) received IC. One hundred sixty-nine surgeons performed the surgeries and accounted for a sizeable proportion of the variability in patient receipt of UD (intraclass correlation coefficient = 0.26). The multilevel model with only patient factors showed good fit (area under the curve = 0.93, Hosmer-Lemeshow test P = .44), and older age, female sex, estimated glomerular filtration rate <45, 4+ comorbidity index score, and stage III/IV tumors were associated with higher odds of receiving an IC vs neobladder/continent pouch. However, including surgeon factors (annual cystectomy volume, specialty training, clinical tenure) had no association (P = .29). CONCLUSION: In this community setting, patient factors were major predictors of UD received. Surgeons also played a substantial role, yet clinical training and experience were not major predictors. Surgeon factors such as beliefs about UD options and outcomes should be explored.

Preliminary Development and Evaluation of an Algorithm to Identify Breast Cancer Chemotherapy Toxicities Using Electronic Medical Records and Administrative Data.

PURPOSE: Breast cancer chemotherapy toxicity is not well documented outside of randomized trials. We developed and conducted preliminary evaluation of an algorithm to detect grade 3 and 4 toxicities using electronic data from a large integrated managed care organization. METHODS: The algorithm used administrative, pharmacy, and electronic data from outpatient, emergency room, and inpatient records of 99 women diagnosed with breast cancer from 2006 to 2009 who underwent chemotherapy. Data were abstracted for 12 months post-treatment initiation (24 months for trastuzumab recipients). An oncology nurse independently blindly reviewed records; these results were the "gold standard." Sensitivity and specificity were calculated for overall toxicity, categories of toxicities, and toxicity by age or regimen. The algorithm was applied to an independent sample of 1,575 patients with breast cancer diagnosed during the study period to estimate prevalence rates. RESULTS: The overall sensitivity for detecting chemotherapy-related toxicity was 89% (95% CI, 77% to 95%). The highest sensitivity was for identification of hematologic toxicities (97%; 95% CI, 84% to 99%). There were good sensitivities for infectious toxicity, but rates dropped for GI and neurological toxicities. Specificity was high within each category (89% to 99%), but when combined to measure any toxicity, it was lower (70%; 95% CI, 57% to 81%). When applied to an independent chemotherapy sample, the algorithm estimates a 26% rate of hematologic toxicity; rates were higher among patients age ≥ 65 years versus less than 65 years. CONCLUSIONS: If validated in other samples and health care settings, algorithms to capture toxicity could be useful in comparative and cost-effectiveness evaluations of community practice-delivered treatment.

Patient awareness and knowledge of breast cancer-related lymphedema in a large, integrated health care delivery system.

Breast cancer patients have voiced dissatisfaction regarding their education on breast cancer-related lymphedema risk and risk reduction strategies from their clinicians. Informing patients about lymphedema can contribute to decrease their risk of developing the condition, or among those already affected, prevent it from progressing further. In this cross-sectional study, a lymphedema awareness score was calculated based on responses to a brief telephone interview conducted among 389 women diagnosed with invasive breast cancer at Kaiser Permanente Northern California from 2000 to 2008 and had a previous record of a lymphedema-related diagnosis or procedure in their electronic medical record. During the telephone interview, women self-reported a lymphedema clinical diagnosis, lymphedema symptoms but no lymphedema diagnosis, or neither a diagnosis nor symptoms, and responded to questions on lymphedema education and support services as well as health knowledge. Multivariable logistic regression [odds ratio (OR) and 95 % confidence interval (CI)] was used to determine the associations of selected sociodemographic and clinical factors with the odds of having lymphedema awareness (adequate vs. inadequate). The median (range) of the lymphedema awareness score was 4 (0-7). Compared with patients <50 years of age, patients 70+ years of age at breast cancer diagnosis had lower odds of adequate lymphedema awareness (OR 0.25; 95 % CI 0.07, 0.89), while patients 50-59 and 60-69 years had greater odds of adequate awareness although not statistically significant (OR 2.05; 95 % CI 0.88, 4.78 and OR 1.55; 95 % CI 0.60, 4.02, respectively; p for trend = 0.09). Higher educational level and greater health literacy were suggestive of adequate awareness yet were not significant. These results can help inform educational interventions to strengthen patient knowledge of lymphedema risk and risk reduction practices, particularly in an integrated health care delivery setting. With the growing population of breast cancer survivors, increasing patient awareness and education about lymphedema risk reduction and care after cancer diagnosis is warranted.

Clinician awareness and knowledge of breast cancer-related lymphedema in a large, integrated health care delivery setting.

Breast cancer survivors have reported dissatisfaction regarding their education on risk of breast cancer-related lymphedema (BCRL) from clinicians. We describe clinician knowledge and treatment referral of patients with BCRL among active oncologists, surgeons, and primary care physicians in the Kaiser Permanente Northern California Medical Care Program. A total of 887 oncologists, surgeons, and primary care clinicians completed a 10-minute web survey from May 2, 2010 to December 31, 2010 on BCRL knowledge, education, and referral patterns. A knowledge score of BCRL was calculated based on clinician responses. Multivariable regression models were used to determine the associations of selected covariates with BCRL knowledge score and clinician referral, respectively. Compared with primary care clinicians, oncologists had the highest mean score followed closely by surgeons (P < 0.0001). In multivariable analyses, being female, an oncologist or surgeon, and recently receiving BCRL materials were each significantly associated with higher BCRL knowledge scores. About 44% of clinicians (n = 381) indicated they had ever made a BCRL referral (100% oncologists, 79% surgeons, and 36% primary care clinicians). Clinicians with a higher knowledge score were more likely to make referrals. In stratified analyses by specialty, the significant associated factors remained for primary care but became non-significant for oncology and surgery. These results can inform educational interventions to strengthen clinician knowledge of the clinical management of BCRL, especially among primary care clinicians. With the growing number of breast cancer survivors, increasing clinician education about BCRL across all specialties is warranted.