Clinical Validation of a Primary Antibody Deficiency Screening Algorithm for Primary Care

PURPOSE

The diagnostic delay of primary antibody deficiencies (PADs) is associated with increased morbidity, mortality, and healthcare costs. Therefore, a screening algorithm was previously developed for the early detection of patients at risk of PAD in primary care. We aimed to clinically validate and optimize the PAD screening algorithm by applying it to a primary care database in the Netherlands.

METHODS

The algorithm was applied to a data set of 61,172 electronic health records (EHRs). Four hundred high-scoring EHRs were screened for exclusion criteria, and remaining patients were invited for serum immunoglobulin analysis and referred if clinically necessary.

RESULTS

Of the 104 patients eligible for inclusion, 16 were referred by their general practitioner for suspected PAD, of whom 10 had a PAD diagnosis. In patients selected by the screening algorithm and included for laboratory analysis, prevalence of PAD was ~ 1:10 versus 1:1700-1:25,000 in the general population. To optimize efficiency of the screening process, we refitted the algorithm with the subset of high-risk patients, which improved the area under the curve-receiver operating characteristics curve value to 0.80 (95% confidence interval 0.63-0.97). We propose a two-step screening process, first applying the original algorithm to distinguish high-risk from low-risk patients, then applying the optimized algorithm to select high-risk patients for serum immunoglobulin analysis.

CONCLUSION

Using the screening algorithm, we were able to identify 10 new PAD patients from a primary care population, thus reducing diagnostic delay. Future studies should address further validation in other populations and full cost-effectiveness analyses.

REGISTRATION

Clinicaltrials.gov record number NCT05310604, first submitted 25 March 2022.

Estimation of Health State Utility Values in Fabry Disease Using Vignette Development and Valuation

Background: Health state utilities are measures of health-related quality of life that reflect the value placed on improvements in patients' health status and are necessary for estimation of quality-adjusted life-years. Health state utility data on Fabry disease (FD) are limited. In this study we used vignette (scenario) construction and valuation to develop health state utilities. Objectives: The aim of this study was to use vignette construction and valuation to estimate health state utility values suitable for inclusion in economic models of FD treatments. Methods: Health state vignettes were developed from semistructured qualitative telephone interviews with patients with FD and informed by published literature and input from an expert. Each vignette was valued in an online survey by members of the United Kingdom (UK) general population using the composite time trade-off (TTO) method, which aims to determine the time the respondent would trade to live in full health compared with each impaired health state. Results: Eight adults (50% women) with FD from the UK were interviewed. They were recruited via various approaches, including patient organizations and social media. The interviewees' responses, evidence from published literature, and input from a clinical expert informed the development of 6 health state vignettes (pain, moderate clinically evident FD [CEFD], severe CEFD, end-stage renal disease [ESRD], stroke, and cardiovascular disease [CVD]) and 3 combined health states (severe CEFD + ESRD, severe CEFD + CVD, and severe CEFD + stroke). A vignette valuation survey was administered to 1222 participants from the UK general population who were members of an external surveying organization and agreed to participate in this study; 1175 surveys were successfully completed and included in the analysis. Responses to TTO questions were converted into utility values for each health state. Pain was the highest valued health state (0.465), and severe CEFD + ESRD was the lowest (0.033). Discussion: Overall, mean utility values declined as the severity of the vignettes increased, indicating that respondents were more willing to trade life-years to avoid a severe health state. Conclusions: Health state vignettes reflect the effects of FD on all major health-related quality-of-life domains and may help to support economic modeling for treatment of FD.

Content validation and psychometric evaluation of the Angioedema Quality of Life Questionnaire for hereditary angioedema

BACKGROUND

There is considerable burden of illness in hereditary angioedema (HAE). However, instruments to assess health-related quality of life (HRQoL) in HAE are limited. The Angioedema Quality of Life Questionnaire (AE-QoL) was developed to measure HRQoL in patients with recurrent angioedema; the validity of the AE-QoL in patients with HAE is described.

METHODS

To identify disease-related experiences with a focus on the impact of HAE on HRQoL, interviews were conducted with a group of clinician experts and patients with HAE from Canada, France, Germany, Spain, the United Kingdom, and the United States, along with a targeted literature review. Concepts were mapped to the AE-QoL to assess item relevance, interpretation, and conceptual coverage. Cognitive interviews assessed item clarity and relevance. A psychometric validation was performed using data from a phase 3 trial.

RESULTS

Interviews were conducted with seven clinicians and 40 adult patients. Patients reported 35 unique impacts of HAE on their lives, the most frequent being on work/school, social relationships, physical activities, and emotions, particularly fear/worrying and anxiety. Saturation for these impacts was reached, and all concepts covered in the AE-QoL were reported during the interviews. Patients agreed that the questionnaire items and response options were clear and relevant, and the 4-week recall period was appropriate. The psychometric validation included data from 64 patients. For AE-QoL total scores, excellent internal consistency (Cronbach's alpha > 0.90), test-retest reliability (intraclass coefficient > 0.80), convergent validity with the Sheehan Disability Scale (r = 0.663), divergent validity with the EQ-5D-5L index (r = 0.292) and EQ-VAS (r = 0.337), and known-groups validity (p < 0.0001; ɳ2 = 0.56) were demonstrated.

CONCLUSIONS

Qualitative and psychometric analyses showed that the AE-QoL is a reliable and valid instrument for measuring HRQoL in adult patients with HAE from six countries.

Long-term lanadelumab treatment improves health-related quality of life in patients with hereditary angioedema

BACKGROUND

Hereditary angioedema (HAE) is associated with substantial disease burden. Lanadelumab reduced the HAE attack rate during 132 weeks' follow-up in the HELP open-label extension (OLE) Study (NCT02741596).

OBJECTIVE

To measure the impact of long-term lanadelumab treatment on patient-reported outcomes (PROs).

METHODS

Rollover patients (completed the 26-week HELP Study [NCT02586805]) and nonrollovers (newly enrolled) received lanadelumab 300 mg every 2 weeks. PROs (Angioedema Quality of Life Questionnaire [AE-QoL], Short Form v2 Health Survey 12 Item version 2, Hospital Anxiety and Depression Scale, Work Productivity and Activity Impairment-General Health Questionnaire, and EQ-5D-5L questionnaire) were assessed at baseline (day 0 of HELP OLE) and various time points until the end-of-study (EOS) visit. The Angioedema Control Test (AECT), Treatment Satisfaction Questionnaire for Medication, and Global Impression of Treatment Response were administered starting at week 52.

RESULTS

The mean (SD) change in AE-QoL total score from baseline to EOS for rollovers (n = 90) was -10.2 (17.9), demonstrating further improvement from HELP in health-related quality of life (HRQoL); 48.9% of rollovers achieved the previously defined 6-point minimal clinically important difference. Nonrollovers (n = 81) reported a change of -19.5 (21.3). Controlled disease (AECT total score ≥10) was reported by 90.2% of rollovers and 95.9% of nonrollovers at EOS. Excellent treatment response was reported by 78.7% of patients and 82.4% of investigators. Results from other PROs indicated a slight improvement in anxiety, high level of satisfaction with treatment, and increased work productivity/activity.

CONCLUSION

Clinically meaningful improvement in HRQoL was demonstrated with long-term lanadelumab treatment, supporting the benefit of lanadelumab therapy associated with attack prevention.

Early Diagnosis of Primary Immunodeficiency Disease Using Clinical Data and Machine Learning

BACKGROUND

Primary immunodeficiency diseases (PIDD) are a group of immune-related disorders that have a current median delay of diagnosis between 6 and 9 years. Early diagnosis and treatment of PIDD has been associated with improved patient outcomes.

OBJECTIVE

To develop a machine learning model using elements within the electronic health record data that are related to prior symptomatic treatment to predict PIDD.

METHODS

We conducted a retrospective study of patients with PIDD identified using inclusion criteria of PIDD-related diagnoses, immunodeficiency-specific medications, and low immunoglobulin levels. We constructed a control group of age-, sex-, and race-matched patients with asthma. The primary outcome was the diagnosis of PIDD. We considered comorbidities, laboratory tests, medications, and radiological orders as features, all before diagnosis and indicative of symptom-related treatment. Features were presented sequentially to logistic regression, elastic net, and random forest classifiers, which were trained using a nested cross-validation approach.

RESULTS

Our cohort consisted of 6422 patients, of whom 247 (4%) were diagnosed with PIDD. Our logistic regression model with comorbidities demonstrated good discrimination between patients with PIDD and those with asthma (c-statistic: 0.62 [0.58-0.65]). Adding laboratory results, medications, and radiological orders improved discrimination (c-statistic: 0.70 vs 0.62, P < .001), sensitivity, and specificity. Extending to the advanced machine learning models did not improve performance.

CONCLUSIONS

We developed a prediction model for early diagnosis of PIDD using historical data that are related to symptomatic care, which has potential to fill an important need in reducing the time to diagnose PIDD, leading to better outcomes for immunodeficient patients.

Trends in characteristics and outcomes among US adults hospitalised with COVID-19 throughout 2020: an observational cohort study

OBJECTIVES

To examine the temporal patterns of patient characteristics, treatments used and outcomes associated with COVID-19 in patients who were hospitalised for the disease between January and 15 November 2020.

DESIGN

Observational cohort study.

SETTING

COVID-19 subset of the Optum deidentified electronic health records, including more than 1.8 million patients from across the USA.

PARTICIPANTS

There were 51 510 hospitalised patients who met the COVID-19 definition, with 37 617 in the laboratory positive cohort and 13 893 in the clinical cohort.

PRIMARY AND SECONDARY OUTCOME MEASURES

Incident acute clinical outcomes, including in-hospital all-cause mortality.

RESULTS

Respectively, 48% and 49% of the laboratory positive and clinical cohorts were women. The 50- 65 age group was the median age group for both cohorts. The use of antivirals and dexamethasone increased over time, fivefold and twofold, respectively, while the use of hydroxychloroquine declined by 98%. Among adult patients in the laboratory positive cohort, absolute age/sex standardised incidence proportion for in-hospital death changed by -0.036 per month (95% CI -0.042 to -0.031) from March to June 2020, but remained fairly flat from June to November, 2020 (0.001 (95% CI -0.001 to 0.003), 17.5% (660 deaths /3986 persons) in March and 10.2% (580/5137) in October); in the clinical cohort, the corresponding changes were -0.024 (95% CI -0.032 to -0.015) and 0.011 (95% CI 0.007 0.014), respectively (14.8% (175/1252) in March, 15.3% (189/1203) in October). Declines in the cumulative incidence of most acute clinical outcomes were observed in the laboratory positive cohort, but not for the clinical cohort.

CONCLUSION

The incidence of adverse clinical outcomes remains high among COVID-19 patients with clinical diagnosis only. Patients with COVID-19 entering the hospital are at elevated risk of adverse outcomes.

Characteristics and outcomes of hospitalised adults with COVID-19 in a Global Health Research Network: a cohort study

OBJECTIVE

To examine age, gender, and temporal differences in baseline characteristics and clinical outcomes of adult patients hospitalised with COVID-19.

DESIGN

A cohort study using deidentified electronic medical records from a Global Research Network.

SETTING/PARTICIPANTS

67 456 adult patients hospitalised with COVID-19 from the USA; 7306 from Europe, Latin America and Asia-Pacific between February 2020 and January 2021.

RESULTS

In the US cohort, compared with patients 18-34 years old, patients ≥65 had a greater risk of intensive care unit (ICU) admission (adjusted HR (aHR) 1.73, 95% CI 1.58 to 1.90), acute respiratory distress syndrome(ARDS)/respiratory failure (aHR 1.86, 95% CI 1.76 to 1.96), invasive mechanical ventilation (IMV, aHR 1.93, 95% CI, 1.73 to 2.15), and all-cause mortality (aHR 5.6, 95% CI 4.36 to 7.18). Men appeared to be at a greater risk for ICU admission (aHR 1.34, 95% CI 1.29 to 1.39), ARDS/respiratory failure (aHR 1.24, 95% CI1.21 to 1.27), IMV (aHR 1.38, 95% CI 1.32 to 1.45), and all-cause mortality (aHR 1.16, 95% CI 1.08 to 1.24) compared with women. Moreover, we observed a greater risk of adverse outcomes during the early pandemic (ie, February-April 2020) compared with later periods. In the ex-US cohort, the age and gender trends were similar; for the temporal trend, the highest proportion of patients with all-cause mortality were also in February-April 2020; however, the highest percentages of patients with IMV and ARDS/respiratory failure were in August-October 2020 followed by February-April 2020.

CONCLUSIONS

This study provided valuable information on the temporal trends of characteristics and outcomes of hospitalised adult COVID-19 patients in both USA and ex-USA. It also described the population at a potentially greater risk for worse clinical outcomes by identifying the age and gender differences. Together, the information could inform the prevention and treatment strategies of COVID-19. Furthermore, it can be used to raise public awareness of COVID-19's impact on vulnerable populations.

Impact of lanadelumab on health-related quality of life in patients with hereditary angioedema in the HELP study

Background

An objective of the phase 3 HELP Study was to investigate the effect of lanadelumab on health‐related quality of life (HRQoL) in patients with hereditary angioedema (HAE).

Methods

Patients with HAE‐1/2 received either lanadelumab 150 mg every 4 weeks (q4wks; n = 28), 300 mg q4wks (n = 29), 300 mg every 2 weeks (q2wks; n = 27), or placebo (n = 41) for 26 weeks (days 0–182). The Angioedema Quality of Life Questionnaire (AE‐QoL) was administered monthly, consisting of four domain (functioning, fatigue/mood, fears/shame, nutrition) and total scores. The generic EQ‐5D‐5L questionnaire was administered on days 0, 98, and 182. Comparisons were made between placebo and (a) all lanadelumab‐treated patients and (b) individual lanadelumab groups for changes in scores (day 0–182) and proportions achieving the minimal clinically important difference (MCID, −6) in AE‐QoL total score.

Results

Compared with the placebo group, the lanadelumab total group demonstrated significantly greater improvements in AE‐QoL total and domain scores (mean change, −13.0 to −29.3; p < 0.05 for all); the largest improvement was in functioning. A significantly greater proportion of the lanadelumab total group achieved the MCID (70% vs 37%; p = 0.001). The lanadelumab 300 mg q2wks group had the highest proportion (81%; p = 0.001) and was 7.2 times more likely to achieve the MCID than the placebo group. Mean EQ‐5D‐5L scores at day 0 were high in all groups, indicating low impairment, with no significant changes at day 182.

Conclusion

Patients with HAE‐1/2 experienced significant and clinically meaningful improvements in HRQoL measured by AE‐QoL following lanadelumab treatment in the HELP Study.

Indirect Comparison of Lanadelumab and Intravenous C1-INH Using Data from the HELP and CHANGE Studies: Bayesian and Frequentist Analyses

BACKGROUND

Hereditary angioedema (HAE) with C1-esterase inhibitor (C1-INH) deficiency is a rare disease associated with painful, potentially fatal swelling episodes affecting subcutaneous or submucosal tissues. HAE attacks recur with unpredictable severity and frequency throughout patients' lives; long-term prophylaxis is essential for some patients. In the absence of head-to-head studies, indirect treatment comparison (ITC) of long-term prophylactic agents is a valid approach to evaluate comparative efficacy.

METHODS

We conducted an ITC using data from the placebo-controlled HELP study (assessing patients receiving lanadelumab 300 mg every 2 or 4 weeks) and the 12-week, parallel arm, crossover CHANGE study (assessing intravenous C1-INH). Outcomes of interest were attack rate ratio (ARR) and time to attack after day 0 (TTA0) and after day 70 (TTA70). Two ITC methodologies were used: a Bayesian approach using study results to update non-informative prior distributions to posterior distributions on relative treatment effects, and a frequentist approach using patient-level data from HELP and CHANGE to generate Poisson regressions (for ARR) and Cox models (for TTA0 and TT70).

RESULTS

Both Bayesian and frequentist analyses suggested that lanadelumab reduced HAE attack rate by 46-73% versus intravenous C1-INH. Relative to intravenous C1-INH, risk of first attack after day 0 was comparable between intravenous C1-INH and both lanadelumab doses; risk of first attack after day 70 was reduced by 81-83% with lanadelumab 300 mg every 2 weeks, compared with C1-INH.

CONCLUSIONS

Findings from these two ITC methodologies support the favorable efficacy of lanadelumab in reducing the HAE attack rate and extending attack-free intervals in patients with HAE.

Clinical characteristics and burden of illness in patients with hereditary angioedema: findings from a multinational patient survey

Background

Hereditary angioedema (HAE) is a rare, debilitating, genetic disease characterized by unpredictable, recurrent, and potentially fatal swelling of the skin and mucous membranes. We conducted a noninterventional, cross-sectional, web-based survey of patients with a self-reported diagnosis of HAE type 1/2 in Australia, Austria, Canada, France, Germany, Spain, Switzerland, and the United Kingdom to gain a comprehensive real-world understanding of the characteristics of HAE and its burden from the perspective of the patient. The survey included questions on clinical and demographic characteristics, burden of disease, and treatment. Instruments used to measure patient-reported outcomes included the Angioedema Quality of Life questionnaire (AE-QoL), 12-Item Short-Form Health Survey (SF-12v2), Angioedema Control Test (AECT), Hospital Anxiety and Depression Scale (HADS), and Work Productivity and Impairment questionnaire (WPAI). Data were analyzed with descriptive statistics.

Results

A total of 242 patients (67.4% female; mean [range] age 43.8 [18–92] years) completed the survey. The mean (SD) age at first symptoms was 11.5 (8.9) years, while diagnosis occurred at 20.8 (13.2) years. Patients reported a mean (SD) of 12.5 (14.1) attacks in the past 6 months. The most recent attack occurred within the past month in 79.7% of patients; most were of moderate severity, 6.6% affected the larynx, 21.9% lasted ≥ 3 days, and 76.4% were treated with on-demand medication. Hospitalizations and emergency/urgent care visits were highest for patients with more attacks. At the time of the survey, 62.4% of patients were using long-term prophylaxis, including 34.4% using androgens. Moderate to severe anxiety and depression were reported in 38.0% and 17.4% of patients, respectively, as measured using the HADS. The severity of anxiety and depression was associated with poorer quality of life and productivity, measured using the AECT (mean overall score 8.00 [moderate perceived disease control]), AE-QoL, WPAI, and SF-12v2. Scores for AECT, AE-QoL, and WPAI were also worse with a higher number of attacks.

Conclusions

This survey study of a broad international sample of patients with HAE showed that despite the availability of on-demand treatment and long-term prophylaxis for the prevention of attacks, patients across a wide geographical area continue to have high disease activity, likely due to restrictions in the availability of medications or incorrect use. Subsequently, significant disease burden, including impaired quality of life and mental health and decreased productivity, was evident. Increased patient education and access to newer, more effective therapies are needed.

Real-world cohort study of adult and pediatric patients treated for hereditary angioedema in the United States

Background: There is limited real-world evidence on hereditary angioedema (HAE) patient characteristics and health-care resource utilization (HCRU); in addition, pediatric patients have been described in small cohorts. Objective: To describe patient characteristics, treatment patterns, and HCRU among adult and pediatric patients treated for HAE in a large U.S. cohort. Methods: This retrospective cohort study used an administrative claims data base (January 2006 to September 2015). Eligible patients with either ≥1 pharmacy claim for HAE-indicated therapies (C1 inhibitors, ecallantide, icatibant) or ≥2 medical claims with codes associated with HAE (per medical billing codes), and ≥1 claim for androgens, fresh frozen plasma, tranexamic acid, or ε-aminocaproic acid formed a "treated cohort." Three nonexclusive treated cohorts were assessed: overall, pediatric, and HCRU (≥2 years of continuous enrollment during 2010-2015). Results: Overall, 1429 patients received treatment (mean ± standard deviation [SD] age, 38.8 ±15.7 years; 62.4% female patients; mean ± SD Charlson Comorbidity Index of 1.4 ± 2.4). Common comorbidities were allergy or anaphylaxis (51.4%) and anxiety or depression (35.8%). Diagnoses indicative of HAE attacks included swelling and/or angioedema (78.5%), abdominal pain (55.6%), and asphyxiation (27.2%). Use of HAE-indicated medication rose between 2006 and 2015 to 81.8%, whereas androgen use declined (from 91.5% to 24.9%). Similar trends were observed in the pediatric treated cohort (n = 143). In the HCRU treated cohort (n = 538), HAE-related claims for emergency department and inpatient admissions were observed for 36.6% and 22.3% of patients, respectively. Conclusion: In a large U.S. cohort of adult and pediatric patients who received treatments indicated or used for HAE, common comorbidities and trends in resource use denoted the substantial burden of attacks, which reflected a continued need that recently approved long-term prophylactic treatments may help to address.

Association between transplant glomerulopathy and graft outcomes following kidney transplantation: A meta-analysis

Transplant glomerulopathy (TG), a morphological lesion associated with confluent mechanisms of endothelial injury of renal allografts, may provide a viable predictor of graft failure. This systematic literature review and meta-analysis were performed according to the PRISMA statement to examine evidence describing the association between TG and graft loss or failure and time to these events. The literature review was conducted using the Scopus, EBSCO, and Cochrane Library search engines. Hazard ratios, median survival times, and 95% confidence intervals (CIs) were estimated to evaluate graft survival in the total population and prespecified subgroups. Meta-regression analysis assessed heterogeneity. Twenty-one publications comprising 6,783 patients were eligible for data extraction and inclusion in the meta-analysis. Studies were highly heterogeneous (I² = 67.3%). The combined hazard ratio of graft loss or failure from random-effects meta-analysis was 3.11 (95% CI 2.44–3.96) in patients with TG compared with those without. Median graft survival in patients with TG was 3.25 (95% CI 0.94–11.21) years—15 years shorter than in those without TG (18.82 [95% CI 10.03–35.32] years). The effect of time from transplantation to biopsy on graft outcomes did not reach statistical significance (p = 0.116). TG was associated with a threefold increase in the risk of graft loss or failure and a 15-year loss in graft survival, indicating viability as a surrogate measure for both clinical practice and studies designed to prevent or reverse antibody-mediated rejection.

Real-world cohort study of adult and pediatric patients treated for hereditary angioedema in the United States

BACKGROUND

There is limited real-world evidence on hereditary angioedema (HAE) patient characteristics and health-careresource utilization (HCRU); in addition, pediatric patients have been described in small cohorts.

OBJECTIVE

To describe patient characteristics, treatment patterns, and HCRU among adult and pediatric patients treatedfor HAE in a large U.S. cohort.

METHODS

This retrospective cohort study used an administrative claims data base (January 2006 to September 2015).Eligible patients with either greater than or equal to one pharmacy claim for HAE-indicated therapies (C1 inhibitors, ecallantide, icatibant) or gtaer than or equal to two medical claims with codes associated with HAE (per medical billing codes), and greater than or equal to one claim for androgens, fresh frozen plasma, tranexamic acid, or « -aminocaproic acid formed a "treated cohort." Three nonexclusive treated cohorts were assessed: overall, pediatric, and HCRU (greater than or equal to 2 years of continuous enrollment during 2010-2015).

RESULTS

Overall, 1429 patients received treatment (mean =/- 6 standard deviation [SD] age, 38.8 +/- 15.7 years; 62.4% femalepatients; mean +/- SD Charlson Comorbidity Index of 1.4 +/- 2.4). Common comorbidities were allergy or anaphylaxis (51.4%)and anxiety or depression (35.8%). Diagnoses indicative of HAE attacks included swelling and/or angioedema (78.5%), abdominalpain (55.6%), and asphyxiation (27.2%). Use of HAE-indicated medication rose between 2006 and 2015 to 81.8%, whereas androgen use declined (from 91.5% to 24.9%). Similar trends were observed in the pediatric treated cohort (n = 143). In the HCRU treated cohort (n = 538), HAE-related claims for emergency department and inpatient admissions were observed for 36.6% and 22.3% of patients, respectively.

CONCLUSION

In a large U.S. cohort of adult and pediatric patients who received treatments indicated or used for HAE,common comorbidities and trends in resource use denoted the substantial burden of attacks, which reflected a continued needthat recently approved long-term prophylactic treatments may help to address.

Patient-reported burden of hereditary angioedema: findings from a patient survey in the United States

BACKGROUND

Hereditary angioedema (HAE) with C1-inhibitor deficiency is associated with painful, potentially fatal attacks affecting subcutaneous or submucosal tissues.

OBJECTIVE

To evaluate HAE burden from the patients' perspective.

METHODS

This was a noninterventional survey of patients with HAE in the United States, conducted from March 17 to April 28, 2017. Patients were recruited through the US Hereditary Angioedema Association. Key eligibility criteria included the following: (1) aged 18 years and older, (2) self-reported physician diagnosis of HAE type I or II, (3) 1 or more HAE attacks or prodromal symptoms within the last year, and (4) receipt of HAE medication for an attack within the last 2 years. Descriptive analyses were conducted.

RESULTS

A total of 445 patients completed the survey. Most patients (92.8%) were aged 18 to 64 years with HAE type I (78.4%) and had a positive family history (78.4%). Mean (SD) ages at symptom onset and diagnosis were 12.5 (9.1) and 20.1 (13.7) years, respectively. Most patients (78.7%) experienced an attack within the past month. The abdomen (58.0%) and extremities (46.1%) were commonly affected sites; pain (73.9%) and abdominal (57.0%) and nonabdominal (55.1%) swelling were frequently reported symptoms. Most patients (68.5%) had received or were currently receiving long-term prophylaxis. Most patients (88.8%) reported visiting allergists or immunologists, whereas 9.2% visited emergency departments or urgent care clinics. Per the Hospital Anxiety and Depression Scale, 49.9% and 24.0% of respondents had anxiety and depression, respectively. Mean Hereditary Angioedema-Quality of Life scores were generally lower with higher attack frequency. General health was "poor" or "fair" for 24.8% of patients. Mean (SD) percentage impairments were 5.9% (14.1%) for absenteeism, 23.0% (25.8%) for presenteeism, 25.4% (28.1%) for work productivity loss, and 31.8% (29.7%) for activity impairment.

CONCLUSION

Despite treatment advances, patients with HAE in the United States continue to have a high burden of illness.

Patterns and Economic Burden of Hospitalizations and Exacerbations Among Patients Diagnosed with Idiopathic Pulmonary Fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a rare and fatal restrictive respiratory disease under the idiopathic lung disease (ILD) class. IPF is a form of chronic, progressive fibrosing interstitial pneumonia and has more scarring, less inflammation, and poorer prognosis than most other ILD forms. Exacerbation of IPF is rapid, with unpredictable deterioration of lung function, and is associated with short-term mortality. The American Thoracic Society (ATS) evidence-based guidelines for diagnosis and management of IPF reports that the incidence of acute exacerbations is between 5%-10%. Limited real-world evidence has been identified in the United States that assesses patterns of hospitalization, exacerbation of IPF, and the associated economic burden.

OBJECTIVES

To (a) characterize patients newly diagnosed with IPF and (b) examine incidence rates and costs of all-cause hospitalizations, IPF-related hospitalizations, and exacerbations.

METHODS

A retrospective analysis was performed with a national commercial claims database from calendar years 2006 to 2011. Newly diagnosed IPF patients were identified with either ≥ 2 claims for idiopathic fibrosing alveolitis (IFA) or ≥ 1 claim for IFA and ≥ 1 claim for postinflammatory pulmonary fibrosis and a lung biopsy or thoracic high-resolution computed tomography within 90 days of the first claim for IFA (index date). IPF-related hospitalizations and possible IPF exacerbations were defined based on diagnoses recorded on event claims. Frequency, incidence rate, duration of events, and associated costs from the third-party payer's perspective were estimated.

RESULTS

Among 1,735 identified IPF patients, 38.6% had at least 1 all-cause hospitalization; 10.8% had IPF-related hospitalizations; 4.6% had suspected IPF exacerbations leading to hospitalization; and 72.1% had suspected IPF exacerbations leading to urgent outpatient visits during the 1-year post-index period. Incident rates for these 4 events were 83 (95% CI = 79-88), 17 (95% CI = 14-19), 7 (95% CI = 6-9), and 277 (95% CI = 269-286) per 100 person-years, respectively. Average costs per event were $13,987 (SD = $41,988), $16,812 (SD = $66,399), $14,731 (SD = $85,468), and $444 (SD = $1,481), respectively.

CONCLUSIONS

Hospitalizations and possible exacerbations among patients with IPF were costly. Appropriate management of IPF needs to be considered to help slow IPF disease progression.

DISCLOSURES

Boehringer Ingelheim Pharmaceuticals, Inc. (BIPI) provided funding for this study. Yu and Devercelli are currently salaried employees of BIPI. Wu, Chuang, Wang, Pan, and Benjamin are currently employees of Evidera, which provides consulting and other research services to pharmaceutical, device, government, and nongovernment organizations. In their salaried positions, they work with a variety of companies and organizations and are precluded from receiving payment or honoraria directly from these organizations for services rendered. Evidera received funding from BIPI to conduct the analysis. Coultas was previously a paid consultant of BIPI. The contents do not represent the views of the Department of Veterans Affairs or the U.S. government. This manuscript does not contain clinical studies or patient data. The authors have full control of all primary data, and they agree to allow the journal to review their data if requested. All authors meet the criteria for authorship as recommended by the International Committee of Medical Journal Editors, and they are fully responsible for all content and editorial decisions and were involved at all stages of manuscript development. The manuscript was drafted by Benjamin, Wu, and Yu and revised by Wang, Pan, Yu, Coultas, and Devercelli. The study was designed by Yu, Wu, Chuang, Wang, Benjamin, and Coultas. Statistical analysis was conducted by Wu, Chuang, and Wang. Senior review was provided by Coultas and Devercelli.

Development and Validation of a Predictive Model to Identify Individuals Likely to Have Undiagnosed Chronic Obstructive Pulmonary Disease Using an Administrative Claims Database

BACKGROUND

Despite the importance of early detection, delayed diagnosis of chronic obstructive pulmonary disease (COPD) is relatively common. Approximately 12 million people in the United States have undiagnosed COPD. Diagnosis of COPD is essential for the timely implementation of interventions, such as smoking cessation programs, drug therapies, and pulmonary rehabilitation, which are aimed at improving outcomes and slowing disease progression.

OBJECTIVE

To develop and validate a predictive model to identify patients likely to have undiagnosed COPD using administrative claims data.

METHODS

A predictive model was developed and validated utilizing a retro-spective cohort of patients with and without a COPD diagnosis (cases and controls), aged 40-89, with a minimum of 24 months of continuous health plan enrollment (Medicare Advantage Prescription Drug [MAPD] and commercial plans), and identified between January 1, 2009, and December 31, 2012, using Humana's claims database. Stratified random sampling based on plan type (commercial or MAPD) and index year was performed to ensure that cases and controls had a similar distribution of these variables. Cases and controls were compared to identify demographic, clinical, and health care resource utilization (HCRU) characteristics associated with a COPD diagnosis. Stepwise logistic regression (SLR), neural networking, and decision trees were used to develop a series of models. The models were trained, validated, and tested on randomly partitioned subsets of the sample (Training, Validation, and Test data subsets). Measures used to evaluate and compare the models included area under the curve (AUC); index of the receiver operating characteristics (ROC) curve; sensitivity, specificity, positive predictive value (PPV); and negative predictive value (NPV). The optimal model was selected based on AUC index on the Test data subset.

RESULTS

A total of 50,880 cases and 50,880 controls were included, with MAPD patients comprising 92% of the study population. Compared with controls, cases had a statistically significantly higher comorbidity burden and HCRU (including hospitalizations, emergency room visits, and medical procedures). The optimal predictive model was generated using SLR, which included 34 variables that were statistically significantly associated with a COPD diagnosis. After adjusting for covariates, anticholinergic bronchodilators (OR = 3.336) and tobacco cessation counseling (OR = 2.871) were found to have a large influence on the model. The final predictive model had an AUC of 0.754, sensitivity of 60%, specificity of 78%, PPV of 73%, and an NPV of 66%.

CONCLUSIONS

This claims-based predictive model provides an acceptable level of accuracy in identifying patients likely to have undiagnosed COPD in a large national health plan. Identification of patients with undiagnosed COPD may enable timely management and lead to improved health outcomes and reduced COPD-related health care expenditures.

Meta-analysis of the association between progression-free survival and overall survival in metastatic colorectal cancer

PURPOSE

The validity of progression-free survival (PFS) as a surrogate endpoint for overall survival (OS) in metastatic colorectal cancer (mCRC) trials has been studied, primarily in first-line treatment. The relationship between PFS and OS has not been well studied in later lines of treatment.

METHODS

We conducted a systematic literature review of mCRC phase 2 and 3 clinical trials that reported OS and PFS (or time-to-progression [TTP]) data. Correlation between endpoints (either PFS alone or PFS aggregated with TTP [PFS_TTP]) was estimated within treatment arms. Treatment effect was the ratio of the median time to OS, PFS, or PFS_TTP in the "control" versus "experimental" arm. We conducted meta-regression analyses and performed receiver-operating characteristic (ROC) analysis.

RESULTS

We analyzed data from 62 articles (23,527 patients). A high positive correlation was found between median PFS_TTP and median OS within treatment arms (r = 0.87; 95% confidence interval [CI], 0.82-0.91) and also between the median OS and median PFS (r = 0.89, 95% CI, 0.83-0.93)]. R(2) was 0.48 for PFS_TTP and 0.59 for PFS; R (2) for PFS_TTP was higher for first-line (R(2) = 0.54) than second-line studies (R(2) = 0.38). The ROC analysis is presented as a conceptual tool for evaluating the performance of PFS as a surrogate for OS at various thresholds.

CONCLUSIONS

The correlation of PFS, alone or aggregated with TTP, with OS in clinical trials of patients with mCRC is robust across lines of therapy and provides a useful means of predicting improvements in OS using PFS data.

Psychometric evaluation of the FACT Colorectal Cancer Symptom Index (FCSI-9): reliability, validity, responsiveness, and clinical meaningfulness

BACKGROUND

Patient-reported outcomes (PROs) are essential for evaluating treatment effects on health-related quality of life and symptoms from the patient's perspective. This study sought to evaluate the psychometric properties of the nine-item Functional Assessment of Cancer Therapy/National Comprehensive Cancer Network Colorectal Cancer Symptom Index (FCSI-9) in a metastatic colorectal cancer (mCRC) population.

METHODS

The FCSI-9 and EQ-5D were administered every 2-4 weeks to mCRC subjects in a phase III clinical trial. Three hundred ninety-one mCRC subjects completed the questionnaires at baseline and at least one follow-up assessment. Internal consistency reliability, test-retest reliability, construct validity, known groups validity, responsiveness, and the minimum important difference (MID) of the FCSI-9 were evaluated.

RESULTS

The internal consistency and test-retest reliability of the FCSI-9 were acceptable (0.81 and 0.76, respectively). Construct validity was supported based on moderate correlations with the EQ-5D. Known groups validity was evaluated by examining the FCSI-9 scores of subjects categorized by their Eastern Cooperative Oncology Group performance status (PS) score. Subjects with better PS scores reported significantly higher FCSI-9 scores than those with lower PS scores at both baseline and week 8. Responsiveness, as measured by Guyatt's statistic, was 0.77 from baseline to week 8 and 0.60 from week 4 to week 12. Considering all data together, the MID of the FCSI-9 is estimated to be in the range of 1.5-3.0 points.

CONCLUSION

Results provide preliminary evidence of the reliability, validity, and responsiveness of the FCSI-9.

Association of progression-free survival, overall survival, and patient-reported outcomes by skin toxicity and KRAS status in patients receiving panitumumab monotherapy

BACKGROUND

The authors explored the association of skin toxicity (ST) severity as measured by patient-reported ST and Common Terminology Criteria for Adverse Events (CTCAE) grading with efficacy of panitumumab, a fully human antiepidermal growth factor receptor antibody, from a phase 3 metastatic colorectal cancer (CRC) trial.

METHODS

Patients were randomized to panitumumab plus best supportive care (BSC) vs BSC alone. ST by modified National Cancer Institute CTCAE v3.0 and modified Dermatology Life Quality Index (mDLQI), health-related quality of life (HRQOL), and CRC symptoms were measured. ST was analyzed using a landmark approach. Associations by KRAS mutational status were also assessed.

RESULTS

Of 463 patients, 208 of 231 (90%) panitumumab patients and 184 of 232 (79%) BSC patients had > or = 1 postbaseline patient-reported outcome (PRO) assessment. Panitumumab patients with more severe ST had significantly longer overall survival (OS) (grade 2-4:grade 1; hazard ratio, 0.60; P = .0033). Lower mDLQI scores (< 67; more bothersome ST) were associated with longer OS (Cox model, P < .0001). Similar results were observed with progression-free survival (PFS). An inverse relation between mDLQI and HRQOL scores was observed, suggesting that ST bother correlated with better HRQOL. KRAS and PRO data were available in 363 patients (188 panitumumab; 175 BSC). Longer OS was associated with lower mDLQI scores, regardless of KRAS status. Longer PFS was associated with more severe ST (lower mDLQI scores and higher CTCAE grade ST) in patients with wild-type (WT) KRAS tumors, but not in patients with mutant KRAS tumors.

CONCLUSIONS

More severe ST, by both clinical grading and PRO, is associated with better CRC symptoms and HRQOL and with longer OS and PFS among panitumumab-treated patients. The associations for PFS were more pronounced in patients with WT KRAS tumors.

Patient-reported outcome (PRO)-assessed clinical benefit with panitumumab (Pmab) in metastatic colorectal cancer (mCRC) patients (pts)

6560

Background: In a phase III study of mCRC pts, Pmab monotherapy significantly improved partial response (PR) rates and progression-free survival (PFS) compared with best supportive care (BSC). This analysis characterizes the clinical benefit of PR/stable disease (SD) and PFS in mCRC pts with respect to health-related quality of life (HRQoL) and CRC symptoms. Methods: Pts had documented disease progression (DP) after treatment (tx) with fluoropyrimidine-, irinotecan-, and oxaliplatin- containing chemotherapy regimens. Pts were randomized 1:1 to receive BSC + Pmab 6mg/kg Q2W. HRQoL (EQ-5D and EORTC QLQ-C30 Global QoL subscale) and CRC symptoms (NCCN/FACT CRC symptom index, FCSI) were assessed at baseline, at least Q4W during tx, and at the 30 day safety follow-up visit. Only pts with PFS ≥ 56 days were included in the analysis to minimize potential lead-time bias associated with response evaluation. T-tests and least square estimates were calculated for differences in PRO measures at 4, 8, 12, 16, and 20 weeks controlling for baseline score by best response (PR or SD vs. other) and by tx arm. Imputation of missing data incorporated each pt's rate of change to assign missing values. Results: In the Pmab arm (n=231), 36% of pts had PR or SD; in the BSC arm (n=232) 10% of pts had SD (no PRs). 109 Pmab pts and 63 BSC pts had at least 1 post-baseline PRO assessment and a PFS time ≥ 56 days. In the Pmab arm, pts with a best response of PR or SD (n=73) had significantly higher mean HRQoL scores at all 5 time points (indicating better HRQoL) compared to those with a best response of < SD (n=36, p=0.03). Consistent results were observed between pts with a best response of PR/SD and CRC symptom scores (p=0.002), indicating less CRC symptomatology. However, in the BSC arm, pts with SD (n=20) had no significant differences in HRQoL or CRC symptoms at any time point compared to pts with < SD (n=43, p=0.12). Results were consistent across all instruments and imputation methods used. Conclusions: These findings show that among Pmab pts with PFS ≥ 56 days, those who had a best response of PR or SD experience significantly higher HRQoL and less CRC symptomatology than Pmab pts without a response. These data suggest that delaying DP may result in clinical benefit.

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Dose increases in patients with chronic myeloid leukemia (CML) treated with imatinib mesylate (IM): Estimated using administrative claims data in a US managed care population

16014

Background: Dose increase is often the first step when resistance is encountered in CML patients treated with IM. The primary objective of this study is to determine the proportion of CML patients who experienced a dose increase from their starting dose within one year after initiation of IM therapy. Methods: Patients ≥18 years of age diagnosed with CML (ICD-9-CM code = 205.1) between 2001 and 2003 and treated with IM were identified in the Pharmetrics Integrated Claims Database which covers a US managed care population. Eligible patients had at least two claims for IM and were continuously enrolled for at least six months following their first IM prescription. Follow-up was one year after their first IM prescription. Results: A total of 113 CML patients using IM were identified. Eighty-four percent of these patients started IM at 400 mg/day; eight percent started at doses ≥ 600 mg/day; remaining started at doses < 400 mg/day The mean daily dose of IM used by the study group was 419 mg (SD = 91). Nineteen percent of users required at least one dose increase from their starting dose within one year. The first dose increase was most frequently 200 mg/day (mean daily dose = 574 mg (SD = 199). The median maximum daily dose reached by patients experiencing dose increases was 600 mg/day (25th– 75th percentile: 500, 750 mg). The median ending dose in these patients was 600 mg/day (25th–75th percentile: 400, 600 mg). Median time to first dose increase was 5.8 (25th–75th percentile: 2.0, 7.4 months). Median time to maximum dose from initial IM dose was 6.5 (25th–75th percentile: 2.7, 7.4 months). Conclusions: Nearly 20% of all IM-treated CML patients required a dose increase of approximately 200 mg/day within one year. Of those dose increases, 50% occurred within the first 6 months.

No significant financial relationships to disclose.

Frequency of treatment changes observed in chronic myeloid leukemia (CML) patients using imatinib mesylate (IM)

16003

Background: Although the response rates in CML associated with IM treatment is well-documented, little research exists on actual practice patterns with IM. The objective of this study is to document treatment changes in a large CML patient population using IM. Methods: Patients ≥ 18 years of age diagnosed with CML (ICD9 = 205.1) between 2000 and 2004 and treated with IM were selected from the Medstat MarketScan Commercial, Medicaid and Medicare Research Databases. Disease phase was defined using a CML specific disease staging algorithm and was assigned at the time of imatinib initiation. A treatment change is defined as evidence of any of the following: any dose increase ≥50 mg, CML treatment added to IM, or IM discontinuation. Summary statistics reported are medians and interquartile ranges (IQR). Results: Four hundred adult IM-treated CML patients (mean age, 56 years; 50% male) were included. 81% and 18% were in chronic phase (CP) and accelerated phase (AP), respectively; with 1% in remission. IM 400 mg was most frequently used regardless of CML phase or year of treatment. The daily starting dose was 400 mg in 305 (78%) patients, 600–799 mg in 34 (9%) patients, ≥ 800 mg in 17 (4%), and the remaining 39 (9%) started at doses < 400 mg. Median follow-up of treatment duration was 9 (IQR: 4.6, 18.9) months. 158 (40%) patients on IM had at least one treatment change, with rates higher in AP patients than in CP (52% vs. 37%). Dose increases were reported in 108 (27%) patients, 3 (<1%) had additional CML treatment, and 64 (16%) discontinued IM altogether. Conclusions: 40% of patients treated with IM had at least one treatment change. The frequency of treatment change increased with longer duration of IM treatment.

[Table: see text]

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Health care utilization and costs among privately insured patients with bipolar I disorder

OBJECTIVE

This study examined health care resource utilization and direct health care costs among patients diagnosed with bipolar I disorder in a privately insured population.

METHODS

Health care claims data for 2883 patients with a primary diagnosis of bipolar disorder were compared over a 1-year period (1997) with claims data for 2883 randomly selected, age- and sex-matched, non-bipolar patients, all covered under the same large private insurer in USA. Resource use (i.e. original and refill pharmaceutical dispensing, medical and procedural services received, inpatient hospitalization, outpatient services, physician visits and emergency room treatment) and their costs are described overall, as well as by bipolar disorder diagnosis (based on ICD-9 codes) and type of care (i.e. mental health versus non-mental health).

RESULTS

Bipolar patients utilized nearly three to four times the health care resources and incurred over four times greater costs per patient compared with the non-bipolar group during the 1-year period ($7663 versus $1962). Inpatient care (hospitalizations) accounted for the greatest disparity between groups, as it was the single-most costly resource in the bipolar group ($2779 versus $398). Patients with bipolar depression (among the single bipolar diagnostic categories of mixed, manic or depressed) incurred the highest health care costs. While mental health care cost was a significant component of total cost in the bipolar group, it accounted for only 22% of the total per-patient cost; in comparison, it accounted for only 6% of the total per-patient cost in the non-bipolar group.

CONCLUSION

Treatment of bipolar disorder, particularly inpatient care, is costly to patients and health insurers. Further study is needed to find ways to reduce the overall cost of managing these patients without jeopardizing patient care.

Health care utilization and costs among privately insured patients with bipolar I disorder

OBJECTIVE

This study examined health care resource utilization and direct health care costs among patients diagnosed with bipolar I disorder in a privately insured population.

METHODS

Health care claims data for 2883 patients with a primary diagnosis of bipolar disorder were compared over a 1-year period (1997) with claims data for 2883 randomly selected, age- and sex-matched, non-bipolar patients, all covered under the same large private insurer in USA. Resource use (i.e. original and refill pharmaceutical dispensing, medical and procedural services received, inpatient hospitalization, outpatient services, physician visits and emergency room treatment) and their costs are described overall, as well as by bipolar disorder diagnosis (based on ICD-9 codes) and type of care (i.e. mental health versus non-mental health).

RESULTS

Bipolar patients utilized nearly three to four times the health care resources and incurred over four times greater costs per patient compared with the non-bipolar group during the 1-year period ($7663 versus $1962). Inpatient care (hospitalizations) accounted for the greatest disparity between groups, as it was the single-most costly resource in the bipolar group ($2779 versus $398). Patients with bipolar depression (among the single bipolar diagnostic categories of mixed, manic or depressed) incurred the highest health care costs. While mental health care cost was a significant component of total cost in the bipolar group, it accounted for only 22% of the total per-patient cost; in comparison, it accounted for only 6% of the total per-patient cost in the non-bipolar group.

CONCLUSION

Treatment of bipolar disorder, particularly inpatient care, is costly to patients and health insurers. Further study is needed to find ways to reduce the overall cost of managing these patients without jeopardizing patient care.

Impact of palivizumab on expected costs of respiratory syncytial virus infection in preterm infants: potential for savings

In its clinical assessment of the respiratory syncytial virus (RSV)-specific monoclonal antibody palivizumab, the IMpact-RSV Study Group demonstrated a reduction in hospitalizations for RSV-related lower respiratory tract infection in infants who received prophylaxis compared with infants who did not receive prophylaxis. An assessment of the RSV-related expenses for managing both groups of infants is needed to provide insight into the value of prophylaxis. The present study was conducted to identify and compare RSV-related health care expenditures incurred by infants who did not receive prophylaxis throughout one RSV season and after. Using a decision-analytic model populated with data from the contemporary medical literature, a pharmacoeconomic study was conducted from the perspective of the payer. Probabilities for RSV-related hospitalizations of infants who did and did not receive prophylaxis were abstracted from several published studies. Components of inpatient and outpatient care were identified through examination of hospital records, reviews of the published literature, and consultation with expert clinicians. Charges related to prophylaxis and medical management of infection were abstracted from hospital billing records and published data. Appropriate charges were applied to decision-tree branches and multiplied by in-line probabilities for outcomes. Products at terminal nodes were summed to establish total expected charges for both groups of infants. Widespread clinical use of prophylactic palivizumab would result in incremental expenses < or =$3459 per infant or cost savings < or =$39,107 per infant. The variability in value of prophylaxis derives from the rate of RSV-related hospitalizations in the community and the total health care expense of managing infected infants.