Impact of neurofibromatosis type 1 with plexiform neurofibromas on the health-related quality of life and work productivity of adult patients and caregivers in the UK: a cross-sectional survey.

BACKGROUND: Plexiform neurofibromas (PN) are complex, benign nerve-sheath tumours that occur in 30-50% of patients with neurofibromatosis type 1 (NF1), a rare, genetic disorder. PN are associated with substantial, heterogeneous morbidities that impact health-related quality of life (HRQoL), including affecting motor function and causing pain, though HRQoL and work productivity data are scarce. This UK cross-sectional study explored HRQoL and work productivity in adult patients with NF1 PN and caregivers of paediatric patients. METHODS: Adult patients and caregivers of paediatric patients self-enrolled in an online survey (March-April 2021). Outcomes included EQ-5D-5L, PROMIS® GH and INF1-QOL (adult patients only), and EQ-5D-5L, CarerQol and WPAI (caregivers only). Utilities were estimated from EQ-5D-5L responses using the UK crosswalk value set. Linear regression models explored univariable associations between adult patient characteristics and HRQoL. RESULTS: Mean (± standard deviation) EQ-5D utility in adult patients with NF1 PN was 0.65 (± 0.29; n = 35; age-/sex-matched norm: 0.89 [± 0.04]). Moderate-extreme pain/discomfort and anxiety/depression were reported by 14/35 (40.0%) and 18/35 (51.4%) patients, respectively. Mean PROMIS® GH physical and mental health scores were 43.6 (± 9.19) and 41.7 (± 11.5; n = 35; matched norm: 50.0 [± 10.0]). Mean INF1-QOL score was 11.03 (± 6.02; n = 33). Chronic itching, at least one symptom, at least one comorbidity, PN location at extremities (arms/legs) and pain were associated with worse HRQoL scores. Mean caregiver EQ-5D utility was 0.72 (± 0.24; n = 8; age-/sex-matched norm: 0.88 [± 0.03]). Moderate pain/discomfort and moderate-severe anxiety/depression were reported by 4/8 (50.0%) and 2/8 (25.0%) caregivers, respectively. Mean CarerQol score was 69.3 (± 13.9; n = 8). Mean WPAI regular activity productivity loss was 36.3% (± 31.6%; n = 8). CONCLUSIONS: NF1 PN worsens adult patient and caregiver HRQoL compared to the general population, notably affecting pain and discomfort, anxiety and depression and caregiver productivity.

Expert opinion on the UK standard of care for haemophilia patients with inhibitors: a modified Delphi consensus study.

BACKGROUND AND AIMS: Despite advances in haemophilia care, inhibitor development remains a significant complication. Although viable treatment options exist, there is some divergence of opinion in the appropriate standard approach to care and goals of treatment. The aim of this study was to assess consensus on United Kingdom (UK) standard of care for child and adult haemophilia patients with inhibitors. METHODS: A modified Delphi study was conducted using a two-round online survey. A haemophilia expert steering committee and published literature informed the Round 1 questionnaire. Invited participants included haematologists, haemophilia nurses and physiotherapists who had treated at least one haemophilia patient with inhibitors in the past 5 years. Consensus for 6-point Likert scale questions was pre-defined as ⩾70% participants selecting 1-2 (disagreement) or 5-6 (agreement). RESULTS: In all, 46.7% and 35.9% questions achieved consensus in Rounds 1 (n = 41) and 2 (n = 34), respectively. Consensus was reached on the importance of improving quality of life (QoL) and reaching clinical goals such as bleed prevention, eradication of inhibitors and pain management. There was agreement on criteria constituting adequate/inadequate responses to immune tolerance induction (ITI) and the appropriate factor VIII dose to address suboptimal ITI response. Opinions varied on treatment aims for adults and children/adolescents, when to offer prophylaxis with bypassing agents and expectations of prophylaxis. Consensus was also lacking on appropriate treatment for mild/moderate patients with inhibitors. CONCLUSION: UK healthcare professionals appear to be aligned on the clinical goals and role of ITI when managing haemophilia patients with inhibitors, although novel treatment developments may require reassessment of these goals. Lack of consensus on prophylaxis with bypassing agents and management of mild/moderate cases identifies a need for further research to establish more comprehensive, evidence-based treatment guidance, particularly for those patients who are unable/prefer not to receive non-factor therapies.

Investigating health-related quality of life in rare diseases: a case study in utility value determination for patients with CLN2 disease (neuronal ceroid lipofuscinosis type 2).

BACKGROUND: Utility studies enable preference-based quantification of a disease's impact on patients' health-related quality of life (HRQoL). It is often difficult to obtain utility values for rare, neurodegenerative conditions due to cognitive burden of direct elicitation methods, and the limited size of patient/caregiver populations. CLN2 disease (neuronal ceroid lipofuscinosis type 2) is an ultra-rare, progressive condition, for which there are no published utility data fully capturing all disease stages. This case study demonstrates how utility values can be estimated for ultra-rare paediatric diseases by asking clinicians to complete EQ-5D-5L questionnaires based on vignettes describing the stages of CLN2 disease. METHODS: An indirect elicitation method using proxy-reporting by clinical experts was adopted. Eighteen vignettes were developed, describing nine progressive disease stages as defined by motor and language domain scores of the CLN2 Clinical Rating Scale, in individuals treated with cerliponase alfa or standard care. Eight clinical experts with experience of treating CLN2 disease with cerliponase alfa and current standard care completed the proxy version 2 EQ-5D-5L online after reading these vignettes. Resulting scores were converted to EQ-5D-5L utility values for each disease stage, using UK, German and Spanish value sets. RESULTS: Utility values, which are typically anchored by 0 (equivalent to death) and 1 (full health), decreased with CLN2 disease progression (results spanned the maximum range of the utility scale). Assigned utility values were consistently higher for patients receiving cerliponase alfa than standard care; differences were statistically significant for the 6 most severe disease stages (p < 0.05). Analysis of the individual dimensions of the EQ-5D-5L showed that greatest differences between patients treated with cerliponase alfa and standard care occurred in the pain dimension (differences in mean scores ranged between no difference and 1.8), with notable differences also observed in the anxiety/depression dimension (differences in mean scores ranged between 0.1 and 1.0). CONCLUSIONS: This study demonstrates a feasible methodology for eliciting utility values in CLN2 disease, indicating HRQoL declines with disease progression. Vignettes describing patients receiving cerliponase alfa were consistently assigned higher utility values for the same disease state, suggesting this treatment improves HRQoL compared with standard care. Trial registration NCT01907087, NCT02485899.

A cost of illness study evaluating the burden of Wolfram syndrome in the United Kingdom.

BACKGROUND: Wolfram syndrome is a rare genetic, progressive, neurodegenerative disorder characterised by childhood-onset diabetes mellitus, diabetes insipidus, optic atrophy and deafness. To date, the economic burden of Wolfram syndrome has not been well-studied or reported. The aim of this study was to evaluate the cost of illness (COI) of all people with Wolfram syndrome in the UK and to identify major determinants of cost from a service provider perspective (National Health Service, NHS). METHODS: A prevalence-based approach was used to model the UK Wolfram syndrome specialist service. Model inputs were informed by a pragmatic literature review and UK reference costs, in conjunction with patient interviews and expert opinion. A deterministic sensitivity analysis (DSA) was run at 10% to identify major cost drivers. RESULTS: The total COI of all people with Wolfram syndrome to the NHS was £1,055,899 per year, with an average annual cost per person with Wolfram syndrome of £16,498. Costs associated with diabetes mellitus care, late-stage diabetes mellitus complications and hearing impairment contributed most to the COI (18.9, 21.4 and 15.8% of the COI, respectively). The DSA identified costs associated with hearing impairment, diabetes mellitus care and end-stage renal disease (a diabetes mellitus complication) as major model drivers. CONCLUSIONS: The annual cost of Wolfram syndrome to the NHS was found to be substantial, with areas of potential cost savings identified, such as diabetes mellitus management. This model provides crucial information to facilitate economic evaluation of prospective therapies for this disease.

Novel functions for integrin-associated proteins revealed by analysis of myofibril attachment in Drosophila.

We use the myotendinous junction of Drosophila flight muscles to explore why many integrin associated proteins (IAPs) are needed and how their function is coordinated. These muscles revealed new functions for IAPs not required for viability: Focal Adhesion Kinase (FAK), RSU1, tensin and vinculin. Genetic interactions demonstrated a balance between positive and negative activities, with vinculin and tensin positively regulating adhesion, while FAK inhibits elevation of integrin activity by tensin, and RSU1 keeps PINCH activity in check. The molecular composition of myofibril termini resolves into 4 distinct layers, one of which is built by a mechanotransduction cascade: vinculin facilitates mechanical opening of filamin, which works with the Arp2/3 activator WASH to build an actin-rich layer positioned between integrins and the first sarcomere. Thus, integration of IAP activity is needed to build the complex architecture of the myotendinous junction, linking the membrane anchor to the sarcomere.

The burden of congenital hyperinsulinism in the United Kingdom: a cost of illness study.

BACKGROUND: Congenital hyperinsulinism (CHI) is a rare, genetic disease which causes persistent hypoglycaemia, typically in new-borns. Patients with the diffuse disease variant often require near-total surgical removal of the pancreas, causing insulin-dependent diabetes mellitus (IDDM). The CHI economic burden is currently unknown. This study aimed to estimate the annual cost of illness (COI) of CHI patients in the UK from a service provider perspective (National Health Service, NHS and Personal Social Services), and to explore cost distribution within the patient population. METHODS: The model was based on standard practice of two CHI centres of excellence. Model inputs were informed by a pragmatic literature review, NHS Reference Costs (2015-2016) and the British National Formulary (2017). Only direct costs to the NHS and Personal Social Services were considered. A prevalence-based approach was used and annual costs incurred at all ages were calculated. A deterministic sensitivity analysis (DSA; run at 10%) identified major cost drivers. RESULTS: The COI of CHI patients to the NHS was £3,408,398.59 annually and average cost per patient was £2124.95. Cost distribution was skewed among CHI patients, with 5.9% of patients (95 patients in their first year of life) contributing to 61.8% (£2,105,491.07) of total costs. DSA results identified lack of response to first-line therapy and IDDM development post surgery (and associated healthcare costs) as major cost drivers. CONCLUSIONS: Despite its rare disease status, estimated annual costs of CHI to the NHS were substantial. Development and management of post-surgical IDDM as a major cost driver highlights the need for effective treatments to mitigate such consequences and costs.