Longitudinal adherence to surveillance for late effects of cancer treatment: a population-based study of adult survivors of childhood cancer.

BACKGROUND: Adult survivors of childhood cancer are at elevated risk of morbidity and mortality compared to the general population, but their adherence to lifelong periodic surveillance is suboptimal. We aimed to examine adherence to surveillance guidelines for high-yield tests and identify risk factors for nonadherence in adult survivors of childhood cancer. METHODS: In this retrospective, population-based cohort study, we used health care administrative data from Ontario, Canada, to identify adult survivors of childhood cancer diagnosed between 1986 and 2014 who were at elevated risk of therapy-related colorectal cancer, breast cancer, or cardiomyopathy. Using a Poisson regression framework, we assessed longitudinal adherence and predictors of adherence to the Children's Oncology Group surveillance guideline. RESULTS: Among 3241 survivors, 327 (10%), 234 (7%), and 3205 (99%) were at elevated risk for colorectal cancer, breast cancer, and cardiomyopathy, respectively. Within these cohorts, only 13%, 6%, and 53% were adherent to recommended surveillance as of February 2020. During a median follow-up of 7.8 years, the proportion of time spent adherent was 14% among survivors at elevated risk for colorectal cancer, 10% for breast cancer, and 43% for cardiomyopathy. Significant predictors of adherence varied across the risk groups, but higher comorbidity was associated with adherence to recommended surveillance. INTERPRETATION: Survivors of childhood cancer in Ontario are rarely up to date for recommended surveillance tests. Tailored interventions beyond specialized clinics are needed to improve surveillance adherence.

Treatment patterns and outcomes in adolescents and young adults with nodular lymphocyte-predominant Hodgkin lymphoma: an IMPACT cohort study.

We leveraged population-based clinical and healthcare data to identify treatment patterns and long-term outcomes among adolescents and young adults (AYA) with nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL). All Ontario, Canada, AYA aged 15-21 years at diagnosis with NLPHL between 1992 and 2012 were identified, and their detailed clinical data were collected. Linkage to healthcare databases identified additional events (subsequent malignant neoplasms [SMN], relapses and deaths). Event-free survival (EFS) and overall survival (OS) were compared by locus of care (adult vs. paediatric) and predictors of outcomes determined. Of 1014 AYA with Hodgkin lymphoma, 54 (5.3%) had NLPHL; 15 (27.8%) were treated at a paediatric centre. No paediatric centre patient received radiation only versus 16 (41.0%) of adult centre patients. Excision only was more common in paediatric centres (p < 0.001). The 20-year EFS and OS rates were 82.9% ± 5.2% and 100% respectively. Advanced stage (hazard ratio: 4.9, 95% CI: 1.3-18.4; p = 0.02) was associated with inferior EFS. Although the 25-year cumulative incidence of SMN was 19.3% ± 9.6% for the entire cohort, there were no SMN among the patients treated with excision only. AYA with NLPHL have outstanding long-term survival. Resection alone was rare outside of paediatric institutions but associated with excellent outcomes. Given substantial SMN risks, chemotherapy-sparing and radiation-sparing strategies for appropriate subsets of patients are warranted.

Ceftazidime Plasma Concentrations and Neurotoxicity: The Importance of Therapeutic Drug Monitoring in Patients Undergoing Different Modalities of Renal Replacement Therapy. A Grand Round.

ABSTRACT: Ceftazidime-avibactam (CTZ-AVM) is a novel cephalosporin/beta-lactamase inhibitor with broad-spectrum activity against multidrug-resistant Pseudomonas aeruginosa . Ceftazidime-induced neurotoxicity is a well-described adverse effect, particularly in patients with renal insufficiency. However, appropriate dosing of ceftazidime-avibactam in patients undergoing renal replacement therapy (RRT) is sparsely investigated, and therapeutic drug monitoring to guide dosing remains lacking. Furthermore, when dose adjustment for impaired renal function is based on CTZ-AVM product information, inferior cure rates have been obtained compared with those with the standard therapy for intra-abdominal infections. Maintaining an effective dose while avoiding toxicity in these patients is challenging. Here, the authors describe the case of a critically ill patient, undergoing 2 modalities of RRT, who developed ceftazidime-induced neurotoxicity as confirmed using ceftazidime therapeutic drug monitoring. This case illustrates a therapeutic drug monitoring-based approach for guiding ceftazidime-avibactam dosing in this context and in diagnosing the cause of neurological symptoms and signs.

Morbidity and healthcare use among mothers of children with cancer: A population-based study.

BACKGROUND: The impact of a child's cancer diagnosis on subsequent maternal physical health is unclear. METHODS: We identified all Ontario children diagnosed less than 18 years with cancer between 1992 and 2017. Linkage to administrative databases identified mothers who were matched to population controls. We identified physical health conditions, acute healthcare use, and preventive healthcare use through validated algorithms using healthcare data, and compared them between exposed (child with cancer) and unexposed mothers. Predictors of health outcomes were assessed among exposed mothers. RESULTS: We identified 5311 exposed mothers and 19,516 matched unexposed mothers. For exposed mothers, median age at last follow-up was 48 years, (interquartile range: 42-53). Exposed mothers had an increased risk of cancer (hazard ratio [HR] 1.2, 95% confidence interval [95% CI]: 1.0-1.5, p = .03), but not of any other adverse physical outcomes or of increased acute healthcare use. Exposed mothers were more likely to receive influenza vaccinations (odds ratio 1.4, 95% CI: 1.3-1.5, p < .0001), and underwent cancer screening at the same rate as unexposed mothers. Among exposed mothers, bereavement was associated with a subsequent increased risk of cancer (HR 1.7, 95% CI: 1.2-2.5, p = .004) and death (HR 2.2, 95% CI: 1.2-4.1, p = .01). CONCLUSION: Mothers of children with cancer are at increased risk of developing cancer, but not of other adverse physical health outcomes, and were equally or more likely to be adherent to preventive healthcare practices. Bereaved mothers were at increased risk of subsequent cancer and death. Interventions targeting specific subpopulations of mothers of children with cancer or focused on screening for specific cancers may be warranted.

Disseminated Aspergillus lentulus Infection in a Heart Transplant Recipient: A Case Report.

We present the first published case of successfully treated disseminated Aspergillus lentulus infection in a solid organ transplant recipient with invasive pulmonary disease, endophthalmitis, and a cerebral abscess. This case highlights important challenges associated with treating A. lentulus, particularly regarding antifungal resistance and toxicities associated with long-term antifungal therapy.

Multispecies Outbreak of Nocardia Infections in Heart Transplant Recipients and Association with Climate Conditions, Australia.

A multispecies outbreak of Nocardia occurred among heart transplant recipients (HTR), but not lung transplant recipients (LTR), in Sydney, New South Wales, Australia, during 2018-2019. We performed a retrospective review of 23 HTR and LTR who had Nocardia spp. infections during June 2015-March 2021, compared risk factors for Nocardia infection, and evaluated climate conditions before, during, and after the period of the 2018-2019 outbreak. Compared with LTR, HTR had a shorter median time from transplant to Nocardia diagnosis, higher prevalence of diabetes, greater use of induction immunosuppression with basiliximab, and increased rates of cellular rejection before Nocardia diagnosis. During the outbreak, Sydney experienced the lowest monthly precipitation and driest surface levels compared with time periods directly before and after the outbreak. Increased immunosuppression of HTR compared with LTR, coupled with extreme weather conditions during 2018-2019, may explain this outbreak of Nocardia infections in HTR.

Emerging therapeutic drug monitoring of anti-infective agents in Australian hospitals: Availability, performance and barriers to implementation.

AIMS: The purpose of the study was to assess the status of emerging therapeutic drug monitoring (TDM) of anti-infective agents in Australian hospitals. METHODS: A nationwide cross-sectional survey of all Australian hospitals operating in the public and private health sector was conducted between August and September 2019. The survey consisted of questions regarding institutional TDM practice for anti-infective agents and clinical vignettes specific to ß-lactam antibiotics. RESULTS: Responses were received from 82 unique institutions, representing all Australian states and territories. All 29 (100%) of principal referral (major) hospitals in Australia participated. Five surveys were partially complete. Only 25% (20/80) of hospitals had TDM testing available on-site for any of the eight emerging TDM candidates considered: ß-lactam antibiotics, anti-tuberculous agents, flucytosine, fluoroquinolones, ganciclovir, human immunodeficiency virus (HIV) drugs, linezolid and teicoplanin. A considerable time lag was noted between TDM sampling and reporting of results. With respect to ß-lactam antibiotic TDM, variable indications, pharmacodynamic targets and sampling times were identified. The three greatest barriers to local TDM performance were found to be (1) lack of timely assays/results, (2) lack of institutional-wide expertise and/or training and (3) lack of guidelines to inform ordering of TDM and interpretation of results. The majority of respondents favoured establishing national TDM guidelines and increasing access to dose prediction software, at rates of 89% and 96%, respectively. CONCLUSION: Translating emerging TDM evidence into daily clinical practice is slow. Concerted efforts are required to address the barriers identified and facilitate the implementation of standardised practice.

Impact of locus of care on outcomes in adolescents and young adults with osteosarcoma and Ewing sarcoma treated at pediatric versus adult cancer centers: An IMPACT cohort study.

BACKGROUND: Location of cancer care (LOC; pediatric vs. adult center) impacts outcomes in adolescents and young adults (AYA) with some cancer types. Data on the impact of LOC on survival in AYA with osteosarcoma (OSS) and Ewing sarcoma (EWS) are limited OBJECTIVES: To compare differences in demographics, disease/treatment characteristics, and survival in a population-based cohort of AYA with OSS or EWS treated at pediatric versus adult centers METHODS: The Initiative to Maximize Progress in Adolescent Cancer Therapy (IMPACT) cohort captured demographic, disease, and treatment data for all AYA (15-21 years old) diagnosed with OSS and EWS in Ontario, Canada between 1992 and 2012. Patients were linked to provincial administrative health care databases. Outcomes were compared between patients treated in pediatric versus adult centers. RESULTS: One hundred thirty-seven AYA were diagnosed with OSS (LOC: 47 pediatric, 90 adult) and 84 with EWS (38 pediatric, 46 adult). AYA treated at pediatric centers were more likely to be enrolled in a clinical trial (OSS 55% vs. 1%, p < .001; EWS 53% vs. 2%, p < .001) and received higher cumulative chemotherapy doses. Five-year event-free survival (EFS ± standard error) in OSS and EWS were 47% ± 4% and 43% ± 5%, respectively. In multivariable analysis, the impact of LOC (pediatric vs. adult center) on EFS in OSS (adjusted hazard ratio [HR] 1.15, 95% confidence interval [CI]: 0.58-2.27, p = .69) and EWS (adjusted HR 1.82, 95% CI: 0.97-3.43, p = .06) was not statistically significant. CONCLUSION: Despite disparities in trial participation and chemotherapy doses, outcomes did not differ by LOC suggesting that AYA with bone tumors can be treated at either pediatric or adult centers.

Morbidity and health care use among siblings of children with cancer: A population-based study.

BACKGROUND: Childhood cancer impacts the entire family unit. We sought to investigate its impact on the long-term physical health outcomes of siblings of children with cancer. PROCEDURE: Pediatric cancer patients diagnosed in Ontario, Canada between 1988 and 2016 were linked to biological siblings. Sibling cases were matched to population controls based on sex, age, geographic location, and number of other children in the family. After individual linkage to health services data, we compared several outcomes between sibling cases and controls: (a) physical health conditions (such as diabetes, hypertension, and death); (b) acute health care use (hospitalization, low- and high-acuity emergency department [ED] visits); and (c) preventive health care use (periodic health checkups, influenza vaccinations). Cox proportional hazards, recurrent event, or logistic regression models were used as appropriate. RESULTS: We identified 8529 sibling cases and 30,364 matched controls (median age at index: 6 years, median age at last follow-up 17 years). Compared to controls, siblings were at increased risk of hypertension (hazard ratio [HR] 1.8; 95% confidence interval [CI] 1.1-2.9; p = .01), had higher rates of low- and high-acuity ED visits (rate ratio 1.1; 95% CI 1.1-1.2; p < .001), and increased risk of hospitalization (HR 1.1; 95% CI 1.1-1.2; p < .001). Sibling cases were also more likely to receive preventive health care (p < .05). CONCLUSION: Increased risk of hypertension, high-acuity ED visits, and hospitalizations suggest that siblings may experience poorer health compared to controls. Counseling families about this potential increased risk and long-term follow-up of siblings to monitor their physical health may be justified.

Evaluation of amikacin use and comparison of the models implemented in two Bayesian forecasting software packages to guide dosing.

AIMS: Bayesian forecasting software can assist in guiding therapeutic drug monitoring (TDM)-based dose adjustments for amikacin to achieve therapeutic targets. This study aimed to evaluate amikacin prescribing and TDM practices, and to determine the suitability of the amikacin model incorporated into the DoseMeRx® software as a replacement for the previously available software (Abbottbase®). METHODS: Patient demographics, pathology, amikacin dosing history, amikacin concentrations and Abbottbase® predicted TDM targets (area under the curve up to 24 hours, maximum concentration and trough concentration) were collected for adults receiving intravenous amikacin (2012-2017). Concordance with the Australian Therapeutic Guidelines was assessed. Observed and predicted amikacin concentrations were compared to determine the predictive performance (bias and precision) of DoseMeRx®. Amikacin TDM targets were predicted by DoseMeRx® and compared to those predicted by Abbottbase®. RESULTS: Overall, guideline compliance for 63 courses of amikacin in 47 patients was suboptimal. Doses were often lower than recommended. For therapy >48 h, TDM sample collection timing was commonly discordant with recommendations, therapeutic target attainment low and 34% of dose adjustments inappropriate. DoseMeRx® under-predicted amikacin concentrations by 0.9 mg/L (95% confidence interval [CI] -1.4 to -0.5) compared with observed concentrations. However, maximum concentration values (n = 19) were unbiased (-1.7 mg/L 95%CI -5.8 to 0.8) and precise (8.6% 95%CI 5.4-18.1). Predicted trough concentration values (n = 7) were, at most, 1 mg/L higher than observed. Amikacin area under the curve values estimated using Abbottbase® (181 mg h/L 95%CI 161-202) and DoseMeRx® (176 mg h/L 95%CI 152-199) were similar (P = .59). CONCLUSION: Amikacin dosing and TDM practice was suboptimal compared with guidelines. The model implemented by DoseMeRx® is satisfactory to guide amikacin dosing.

Influence of chronic comorbidities on periodic colorectal cancer screening participation: A population-based cohort study.

Guidelines recommend regular screening for colorectal cancer (CRC). We examined the effects of chronic comorbidities on periodic CRC testing. Using linked healthcare databases from Ontario, Canada, we assembled a population-based cohort of 50-74-year olds overdue for guideline-recommended CRC screening between April 1, 2004 and March 31, 2016. We implemented multivariable recurrent events models to determine the association between comorbidities and the rate of becoming up-to-date with periodic CRC tests. The cohort included 4,642,422 individuals. CRC testing rates were significantly lower in persons with renal disease on dialysis (hazard ratio, HR 0.66, 95% confidence interval, CI 0.63 to 0.68), heart failure (HR 0.75, CI 0.75 to 0.76), respiratory disease (HR 0.84, CI 0.83 to 0.84), cardiovascular disease (HR 0.85, CI 0.84 to 0.85), diabetes (HR 0.86, 95% CI 0.86 to 0.87) and mental illness (HR 0.88, CI 0.87 to 0.88). There was an inverse association between the number of medical conditions and the rate of CRC testing (5 vs. none: HR 0.30, CI 0.25 to 0.36; 4 vs. none: HR 0.48, CI 0.47 to 0.50; 3 vs. none: HR 0.59, CI 0.58 to 0.60; 2 vs. none: HR 0.72, CI 0.71 to 0.72; 1 vs. none: HR 0.85, CI 0.84 to 0.85). Having both medical and mental comorbidities was associated with lower testing rates than either type of comorbidity alone (HR 0.72, CI 0.71 to 0.72). In summary, chronic comorbidities present a barrier to periodic guideline-recommended CRC testing. Exploration of cancer prevention gaps in these populations is warranted.

Adolescents and young adult acute myeloid leukemia outcomes at pediatric versus adult centers: A population-based study.

BACKGROUND: Adolescents and young adult (AYA) acute myeloid leukemia (AML) outcomes remain poor. The impact of locus of care (LOC; adult vs pediatric) in this population is unknown. PROCEDURE: The IMPACT cohort comprises detailed data for all Ontario, Canada, AYA aged 15-21 years diagnosed with AML between 1992 and 2012, linked to population-based health administrative data. We determined the impact of LOC on event-free survival (EFS) and overall survival (OS), treatment-related mortality (TRM), and relapse/progression. RESULTS: Among 140 AYA, 51 (36.4%) received therapy at pediatric centers. The five-year EFS and OS for the whole cohort were 35.0% ± 4.0% and 53.6% ± 4.2%. Cumulative doses of anthracycline were higher among pediatric center AYA [median 355 mg/m2 , interquartile range (IQR) 135-492 vs 202 mg/m2 , IQR 140-364; P = 0.003]. In multivariable analyses, LOC was not predictive of either EFS [adult vs pediatric center hazard ratio (HR) 1.3, 95% confidence interval (CI) 0.8-2.2, P = 0.27] or OS (HR 1.0, CI 0.6-1.6, P = 0.97). However, patterns of treatment failure varied; higher two-year incidence of TRM in pediatric centers (23.5% ± 6.0% vs.10.1% ± 3.2%; P = 0.046) was balanced by lower five-year incidence of relapse/progression (33.3% ± 6.7% vs 56.2% ± 5.3%; P = 0.002). CONCLUSIONS: AYA AML survival outcomes did not vary between pediatric and adult settings. Causes of treatment failure were different, with higher intensity pediatric protocols associated with higher TRM but lower relapse/progression. Careful risk stratification and enhanced supportive care may be of substantial benefit to AYA with AML by allocating maximal treatment intensity to patients who most benefit while minimizing the risk of TRM.

A retrospective study to determine the cefepime-induced neurotoxicity threshold in hospitalized patients.

OBJECTIVES: Cefepime-induced neurotoxicity (CIN) has been demonstrated to be associated with cefepime plasma concentrations; however, the toxicity threshold remains unclear. The primary objective of this study was to identify the cefepime plasma trough concentration at which neurotoxicity occurs. Secondary objectives were to determine the incidence of CIN at a large tertiary institution and to identify patient factors associated with the development of CIN. METHODS: A retrospective review of all adult patients administered cefepime between October 2017 and May 2018 in a tertiary hospital was conducted to determine total incidence of CIN. A receiver operating characteristic (ROC) curve was constructed to review the sensitivity and specificity of using various cefepime trough plasma concentrations to predict the development of neurotoxicity. Cefepime plasma concentrations were measured using ultra-HPLC. A regression was conducted to identify patient factors associated with CIN. RESULTS: In total, 206 patients were administered 259 courses of cefepime, with an overall CIN incidence of 6% (16/259 courses). A total of 64 courses had a cefepime trough concentration measured (24.7%). A cefepime trough concentration of 36 mg/L provided the best differentiation between patients who experienced neurotoxicity and those who did not. No other patient covariates were identified to be significantly associated with neurotoxicity occurring. CONCLUSIONS: A cefepime trough plasma concentration ≥36 mg/L appears to be the most sensitive and specific cut-off to predict CIN occurring. No patient factors were associated with the development of CIN when accounting for cefepime trough plasma concentrations.

Reoperation cascade in postmastectomy breast reconstruction and its associated factors: Results from a long-term population-based study.

BACKGROUND: Unplanned surgeries following postmastectomy breast reconstruction (PMBR) may be required to treat complications or to revise the reconstructed breast. The primary objective of this study was to examine factors that influenced unplanned reoperations after PMBR. METHODS: A retrospective cohort study using provincial databases in Ontario, Canada, was completed. Patients with breast cancer underwent mastectomy between April 2002 and March 2012 followed by immediate or delayed PMBR. Primary outcome was time from PMBR to unplanned reoperations measured in years. The Anderson-Gill counting process model was used to estimate the risk of recurrent unplanned reoperations over time. Univariate and multivariate analyses were completed to examine the association between covariates. RESULTS: A total of 3066 women underwent PMBR and 51.7% had at least one unplanned reoperation. Unplanned breast reoperation was significantly associated with microsurgical tissue vs implant-based reconstruction (hazard ratio [HR]: 1.27), radiation after PMBR (HR: 1.22), surgery at a nonteaching hospital (HR: 1.16), patient comorbidity score (HR: 1.02), and prior unplanned reoperations (HR: 1.25). CONCLUSIONS: Our study provides important long-term population-level data regarding factors influencing unplanned reoperations after PMBR. Patients undergoing microsurgical PMBR or postmastectomy radiation had a higher rate of additional procedures. Every additional reoperation also increases the likelihood of unplanned reoperations resulting in a "reoperation cascade."

Estimating the incidence of first-episode psychosis using population-based health administrative data to inform early psychosis intervention services.

BACKGROUND: Discrepancies between population-based estimates of the incidence of psychotic disorder and the treated incidence reported by early psychosis intervention (EPI) programs suggest additional cases may be receiving services elsewhere in the health system. Our objective was to estimate the incidence of non-affective psychotic disorder in the catchment area of an EPI program, and compare this to EPI-treated incidence estimates. METHODS: We constructed a retrospective cohort (1997-2015) of incident cases of non-affective psychosis aged 16-50 years in an EPI program catchment using population-based linked health administrative data. Cases were identified by either one hospitalization or two outpatient physician billings within a 12-month period with a diagnosis of non-affective psychosis. We estimated the cumulative incidence and EPI-treated incidence of non-affective psychosis using denominator data from the census. We also estimated the incidence of first-episode psychosis (people who would meet the case definition for an EPI program) using a novel approach. RESULTS: Our case definition identified 3245 cases of incident non-affective psychosis over the 17-year period. We estimate that the incidence of first-episode non-affective psychosis in the program catchment area is 33.3 per 100 000 per year (95% CI 31.4-35.1), which is more than twice as high as the EPI-treated incidence of 18.8 per 100 000 per year (95% CI 17.4-20.3). CONCLUSIONS: Case ascertainment strategies limited to specialized psychiatric services may substantially underestimate the incidence of non-affective psychotic disorders, relative to population-based estimates. Accurate information on the epidemiology of first-episode psychosis will enable us to more effectively resource EPI services and evaluate their coverage.

Adverse mental health outcomes in a population-based cohort of survivors of childhood cancer.

BACKGROUND: The elevated risk for physical late effects in childhood cancer survivors (CCS) is well documented, but their risk for mental health problems is less well described. METHODS: The authors assembled a cohort of all 5-year CCS who were diagnosed before age 18 years and treated in an Ontario pediatric cancer center between 1987 and 2008. Patients were matched to population controls and linked to health administration databases. The authors calculated rates of mental health care visits (family physician, psychiatrist, emergency department, hospitalization) and the risk for a severe mental health event (emergency department, hospitalization, suicide). Outcomes were compared using recurrent event and survival analyses. RESULTS: Compared with 20,269 controls, 4117 CCS had a higher rate of mental health visits (adjusted relative rate [RR], 1.34; 95% confidence interval [CI], 1.12-1.52). Higher rates were associated with female gender (RR, 1.39; CI, 1.10-1.75; P = .006) and being diagnosed at ages 15 to 17.9 years (compared with ages 0-4 years: RR, 1.81; 95% CI, 1.17-2.80; P = .008). Cancer type, treatment intensity, and treatments targeting the central nervous system were not significant predictors. Survivors were at increased risk for a severe event compared with controls (adjusted hazard ratio, 1.13; 95% CI, 1.00-1.28; P = .045). CCS who were diagnosed with cancer at age 4 years or younger were at greatest risk: 16.3% (95% CI, 13.2%-19.8%) had experienced a severe event by age 28 years. CONCLUSIONS: CCS experienced higher rates of mental health visits and a greater risk for a severe event than the general population. Survivors of adolescent cancer have a higher rate of mental health visits overall, whereas survivors of cancer before age 4 years have a markedly elevated risk of severe events. Cancer 2018;124:2045-57. © 2018 American Cancer Society.

Validity of Administrative Data in Identifying Cancer-related Events in Adolescents and Young Adults: A Population-based Study Using the IMPACT Cohort.

BACKGROUND: Despite the importance of estimating population level cancer outcomes, most registries do not collect critical events such as relapse. Attempts to use health administrative data to identify these events have focused on older adults and have been mostly unsuccessful. We developed and tested administrative data-based algorithms in a population-based cohort of adolescents and young adults with cancer. METHODS: We identified all Ontario adolescents and young adults 15-21 years old diagnosed with leukemia, lymphoma, sarcoma, or testicular cancer between 1992-2012. Chart abstraction determined the end of initial treatment (EOIT) date and subsequent cancer-related events (progression, relapse, second cancer). Linkage to population-based administrative databases identified fee and procedure codes indicating cancer treatment or palliative care. Algorithms determining EOIT based on a time interval free of treatment-associated codes, and new cancer-related events based on billing codes, were compared with chart-abstracted data. RESULTS: The cohort comprised 1404 patients. Time periods free of treatment-associated codes did not validly identify EOIT dates; using subsequent codes to identify new cancer events was thus associated with low sensitivity (56.2%). However, using administrative data codes that occurred after the EOIT date based on chart abstraction, the first cancer-related event was identified with excellent validity (sensitivity, 87.0%; specificity, 93.3%; positive predictive value, 81.5%; negative predictive value, 95.5%). CONCLUSIONS: Although administrative data alone did not validly identify cancer-related events, administrative data in combination with chart collected EOIT dates was associated with excellent validity. The collection of EOIT dates by cancer registries would significantly expand the potential of administrative data linkage to assess cancer outcomes.

Disparities in Access to Early Psychosis Intervention Services: Comparison of Service Users and Nonusers in Health Administrative Data.

OBJECTIVE: There is a dearth of information on people with first-episode psychosis who do not access specialized early psychosis intervention (EPI) services. We sought to estimate the proportion of incident cases of nonaffective psychosis that do not access these services and to examine factors associated with EPI admission. METHODS: Using health administrative data, we constructed a retrospective cohort of incident cases of nonaffective psychosis in the catchment area of the Prevention and Early Intervention Program for Psychoses (PEPP) in London, Ontario, between 1997 and 2013. This cohort was linked to primary data from PEPP to identify EPI users. We used multivariate logistic regression to model sociodemographic and service factors associated with EPI admission. RESULTS: Over 50% of suspected cases of nonaffective psychosis did not have contact with EPI services for screening or admission. EPI users were significantly younger, more likely to be male (odds ratio [OR] 1.58; 95% confidence interval [CI] 1.24 to 2.01), and less likely to live in areas of socioeconomic deprivation (OR 0.51; 95% CI 0.36 to 0.73). EPI users also had higher odds of psychiatrist involvement at the index diagnosis (OR 7.35; 95% CI 5.43 to 10.00), had lower odds of receiving the index diagnosis in an outpatient setting (OR 0.50; 95% CI 0.38 to 0.65), and had lower odds of prior alcohol-related (OR 0.42; 95% CI 0.28 to 0.63) and substance-related (OR 0.68; 95% CI 0.50 to 0.93) disorders. CONCLUSIONS: We need a greater consideration of patients with first-episode psychosis who are not accessing EPI services. Our findings suggest that this group is sizable, and there may be sociodemographic and clinical disparities in access. Nonpsychiatric health professionals could be targeted with interventions aimed at increasing detection and referral rates.

ADHD Treatment in Primary Care: Demographic Factors, Medication Trends, and Treatment Predictors.

BACKGROUND: The aim of this study is to determine the prevalence and characteristics of youth with attention-deficit hyperactivity disorder (ADHD) in Ontario, Canada, and to determine the predictors of psychotropic medication prescriptions in youth with ADHD. METHOD: This is a cross-sectional retrospective chart abstraction of more than 250 000 medical records from youth aged 1 to 24 years in a large geographical region in Ontario, Canada, linked to population-based health administrative data. A total of 10 000 charts were randomly selected and manually reviewed using predetermined criteria for ADHD and comorbidities. Prevalence, comorbidities, demographic indicators, and health service utilization characteristics were calculated. Predictors of treatment characteristics were determined using logistic regression modelling. RESULTS: The prevalence of ADHD was 5.4% (7.9% males, 2.7% females). Youth with ADHD had significant psychiatric comorbidities. The majority (70.0%) of ADHD patients received prescriptions for stimulant or nonstimulant ADHD medication. Antipsychotic prescriptions were provided to 11.9% of ADHD patients versus 0.9% of patients without ADHD. Antidepressant prescriptions were provided to 19.8% versus 5.4% of patients with and without ADHD, respectively. Predictors of antidepressant prescriptions were increasing age (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.07 to 1.21), psychiatric consultation (OR, 2.04; 95% CI, 1.16 to 3.58), and diagnoses of both anxiety and depression (OR, 18.4; 95% CI, 8.03 to 42.1), whereas the only predictor of antipsychotic prescriptions was psychiatric consultation (OR, 3.85; 95% CI, 2.11 to 7.02). CONCLUSIONS: Youth with ADHD have more psychiatric comorbidities than youth without ADHD. The majority of youth with ADHD received stimulant medications, and a significant number received additional psychotropic medications, with psychiatric consultation predicting medication use.