The relationship between frequency and severity of vaso-occlusive crises and health-related quality of life and work productivity in adults with sickle cell disease.

PURPOSE: Patients with sickle cell disease (SCD) may experience sickle cell-related pain crises, also referred to as vaso-occlusive crises (VOCs), which are a substantial cause of morbidity and mortality. The study explored how VOC frequency and severity impacts health-related quality of life (HRQoL) and work productivity. METHODS: Three hundred and three adults with SCD who completed an online survey were included in the analysis. Patients answered questions regarding their experience with SCD and VOCs, and completed the Adult Sickle Cell Quality of Life Measurement Information System (ASCQ-Me) and the Workplace Productivity and Activity Impairment: Specific Health Problem (WPAI:SHP). Differences in ASCQ-Me and WPAI:SHP domains were assessed according to VOC frequency and severity. RESULTS: Nearly half of the patient sample (47.2%) experienced ≥ 4 VOCs in the past 12 months. The most commonly reported barriers to receiving care for SCD included discrimination by or trouble trusting healthcare professionals (39.6%, 33.3%, respectively), limited access to treatment centers (38.9%), and difficulty affording services (29.4%). Patients with more frequent VOCs reported greater impacts on emotion, social functioning, stiffness, sleep and pain, and greater absenteeism, overall productivity loss, and activity impairment than patients with less frequent VOCs (P < 0.05). Significant impacts on HRQoL and work productivity were also observed when stratifying by VOC severity (P < 0.05 for all ASCQ-Me and WPAI domains, except for presenteeism). CONCLUSIONS: Results from the survey indicated that patients with SCD who had more frequent or severe VOCs experienced deficits in multiple domains of HRQoL and work productivity. Future research should examine the longitudinal relationship between these outcomes.

Treatment patterns and economic burden of sickle-cell disease patients prescribed hydroxyurea: a retrospective claims-based study.

BACKGROUND: This study aimed to evaluate sickle-cell disease (SCD) treatment patterns and economic burden among patients prescribed hydroxyurea (HU) in the US, through claims data. METHODS: SCD patients with pharmacy claims for HU were selected from the Medicaid Analytic Extracts (MAX) from January 1, 2009 - December 31, 2013. The first HU prescription during the identification period was defined as the index date and patients were required to have had continuous medical and pharmacy benefits for ≥6 months baseline and 12 months follow-up periods. Patient demographics, clinical characteristics, treatment patterns, health care utilization, and costs were examined, and variables were analyzed descriptively. RESULTS: A total of 3999 SCD patients prescribed HU were included; the mean age was 19.24 years, most patients were African American (73.3%), and the mean Charlson comorbidity index (CCI) score was 0.6. Asthma (20.3%), acute chest syndrome (15.6%), and infectious and parasitic diseases (20%) were the most prevalent comorbidities. During the 12-month follow-up period, 58.9% (N = 2357) of patients discontinued HU medication. The mean medication possession ratio (MPR) was 0.52, and 22.3% of patients had MPR ≥80%. The average length of stay (LOS) for SCD-related hospitalization was 13.35 days; 64% of patients had ≥1 SCD-related hospitalization. The mean annual total SCD-related costs per patient were $27,779, mostly inpatient costs ($20,128). CONCLUSIONS: Overall, the study showed the patients had significant unmet needs manifest as poor medication adherence, high treatment discontinuation rates, and high economic burden.

Systematic literature review and assessment of patient-reported outcome instruments in sickle cell disease.

BACKGROUND: Sickle cell disease (SCD) is a chronic condition associated with high mortality and morbidity. It is characterized by acute clinical symptoms such as painful vaso-occlusive crises, which can impair health-related quality of life (HRQL). This study was conducted to identify validated patient-reported outcome (PRO) instruments for use in future trials of potential treatments for SCD. METHODS: A systematic literature review (SLR) was performed using MEDLINE and EMBASE to identify United States (US)-based studies published in English between 1997 and 2017 that reported on validated PRO instruments used in randomized controlled trials and real-world settings. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist was used to assess the quality of PRO instruments. RESULTS: The SLR included 21 studies assessing the psychometric properties of 24 PRO instruments. Fifteen of those instruments were developed and validated for adults and 10 for children (one instrument was used in both children and young adults aged up to 21 years). Only five of the 15 adult instruments and three of the 10 pediatric instruments were developed specifically for SCD. For most instruments, there were few or no data on validation conducted in SCD development cohorts. Of the 24 PRO instruments identified, 16 had strong internal reliability (Cronbach's α ≥0.80). There was often insufficient information to assess the content validity, construct validity, responsiveness, or test-retest reliability of the instruments identified for both child and adult populations. No validated PRO instruments measuring caregiver burden in SCD were identified. CONCLUSIONS: The evidence on the psychometric properties of PRO instruments was limited. However, the results of this SLR provide key information on such tools to help inform the design of future clinical trials for patients with SCD in the US.

Evaluation of Vaso-occlusive Crises in United States Sickle Cell Disease Patients: A Retrospective Claims-based Study.

Sickle cell disease (SCD) is a life-threatening vascular disease that burdens affected persons physically. SCD-related vaso-occlusive crises (VOCs) are one of the primary causes of morbidity and mortality. Our objective was to examine the epidemiology of pain crises and the relationship between pain crises and major acute complications among SCD patients. Using the Medicaid Analytic Extracts from 2009-2013, patients with SCD were selected and the first clinical claim indicating SCD during the identification period was defined as the index date. Patients were required to have continuous Medicaid enrollment for ≥6 months pre- and 12 months post-index period. Clinical outcomes included mortality, inpatient pain crises, and complications. Cox regressions were applied to examine the relationship between pain crises and deaths or acute complications, respectively. A total of 20 909 patients were included with a mean age of 17.9 years. The rate of VOC events in 100 person-years was 142.20 for adults and 53.91 for pediatric patients. Patients with VOCs were associated with a higher risk for death (hazard ratio=1.56; 95% confidence interval: [1.19-2.05]) or acute complications including acute chest syndrome, stroke, pulmonary embolism, splenic sequestration, and pulmonary hypertension. SCD patients have a substantial burden of disease-related complications. This study suggests that inpatient vaso-occlusive crisis is a key risk factor for acute complications.