Health related quality of life measures in Friedreich Ataxia

Factors Influencing Health-Related Quality of Life of Patients with Spinocerebellar Ataxia

BACKGROUND

Little is known about the progression of health-related quality of life (HRQoL) and predicting factors in spinocerebellar ataxia (SCA). Such knowledge is crucial to identify modifiable factors promoting everyday life with SCA and attenuating HRQoL decline.

OBJECTIVES

This study is to assess HRQoL progression and identify factors affecting SCA patients' HRQoL.

METHODS

Longitudinal data (three-year follow-up) of 310 SCA patients of the European SCA3/Machado-Joseph-Disease Initiative (ESMI) (2016-2022) and 525 SCA patients (SCA1, SCA2, SCA3 or SCA6) of the EUROSCA natural history study cohort (2006-2015) were assessed. Both large cohort studies share standardized assessments of clinical measures, SARA, INAS, PHQ-9, and HRQoL (EQ-5D-3L). The association between HRQoL and clinical measures was assessed by Spearman Correlation (rs). Multivariable panel regression models were performed to evaluate the impact of patients' socio-demographics, age of onset, SCA type and body mass index (BMI), and clinical measures on HRQoL progression.

RESULTS

HRQoL significantly decreased over one (- 0.014, p = 0.095), two (- 0.028, p = 0.003), and three years (- 0.032, p = 0.002). Ataxia severity and mental health strongly correlated with HRQoL (rsSARA = - 0.589; rsPHQ-9 = - 0.507). HRQoL more intensively declined in male (ß = - 0.024, p = 0.038) patients with an earlier age of onset (ß = 0.002, p = 0.058). Higher progression of ataxia severity (ß = - 0.010, p ≤ 0.001), mental health problems (ß = - 0.012, p < 0.001), and higher BMI (ß = - 0.003, p = 0.029) caused more severe decline of patients' HRQoL over time.

DISCUSSION

In absence of curative treatments, stronger focus on mental health and weight influence could help clinical evaluation and accompany treatment improving SCA patients' HRQoL, especially in male patients with early disease onset.

Health-Related Quality of Life in Patients with Spinocerebellar Ataxia: a Validation Study of the EQ-5D-3L

Although health-related quality of life (HRQoL) has developed into a crucial outcome parameter in clinical research, evidence of the EQ-5D-3L validation performance is lacking in patients with spinocerebellar ataxia (SCA) types 1, 2, 3, and 6. The objective of this study is to assess the acceptability, validity, reliability, and responsiveness of the EQ-5D-3L. For n = 842 predominantly European SCA patients of two longitudinal cohort studies, the EQ-5D-3L, PHQ-9 (Patient Health Questionnaire), and ataxia-specific clinical assessments (SARA: Scale for Assessment and Rating of Ataxia; ADL: activities of daily living as part of Friedreich's Ataxia Rating Scale; INAS: Inventory of Non-Ataxia Signs) were assessed at baseline and multiple annual follow-ups. The EQ-5D-3L was evaluated regarding acceptability, distribution properties, convergent and known-groups validity, test-retest reliability, and effect size measures to analyze health changes. The non-item response was low (EQ-5D-3L index: 0.8%; EQ-VAS: 3.4%). Ceiling effects occurred in 9.9% (EQ-5D-3L) and 3.0% (EQ-VAS) with a mean EQ-5D-3L index of 0.65 ± 0.21. In total, convergent validity showed moderate to strong Spearman's rho (rs > 0.3) coefficients comparing EQ-5D-3L and EQ-VAS with PHQ-9, SARA, ADL, and INAS. EQ-5D-3L could discriminate between groups of age, SARA, ADL, and INAS. Intra-class correlation coefficients (EQ-5D-3LICC: 0.95/EQ-VASICC: 0.88) and Kappa statistics (range 0.44 to 0.93 for EQ-5D-3L items) indicated tolerable reliability. EQ-5D-3L shows small (effect size < 0.3) to moderate (effect size 0.3-0.59) health changes regarding ataxia severity. The analysis confirms an acceptable, reliable, valid, and responsive recommended EQ-5D-3L in SCA patients, measuring the HRQoL adequately, besides well-established clinical instruments.

The Impact of Demographic and Clinical Factors on the Quality of Life in Patients with Neurodegenerative Cerebellar Ataxias

In neurodegenerative cerebellar ataxias, not only ataxia but also extra-cerebellar signs have a significant impact on patients' health related to quality of life (HRQoL). The aim of this study was to evaluate the various aspects of HRQoL and predictors of QoL in patients with neurodegenerative cerebellar ataxias. We included a total of 107 patients with cerebellar degenerative ataxia. Patients filled out the validated Serbian version of the SF-36 used for the assessment of HRQoL. All patients were clinically evaluated using SARA, INAS, and neuropsychological tests to assess their global cognitive status and different psychiatric scales. The most frequent types of neurodegenerative cerebellar ataxias were autosomal dominant ataxias (38.3%) and sporadic ataxias (32.7%). Mean age at diagnosis was 35.3 ± 16.23 years, and disease duration was on average 12.1 ± 9.91 years. Mean total SF-36 score was 50.63 ± 20.50. Hierarchical regression analysis showed that in the case of the PHC score, the most significant predictors are the patient's actual age, severity of ataxia, and ACE total score. For MHC, the Hamilton depression score was the most important predictor. Our study has shown that HRQoL measured by SF-36 in patients with neurodegenerative cerebellar disorders is strongly influenced by impaired mobility and depression.

Patient-reported, health economic and psychosocial outcomes in patients with Friedreich ataxia (PROFA): protocol of an observational study using momentary data assessments via mobile health app

INTRODUCTION

Friedreich ataxia (FA) is the most common hereditary ataxia in Europe, characterised by progressively worsening movement and speech impairments with a typical onset before the age of 25 years. The symptoms affect the patients' health-related quality of life (HRQoL) and psychosocial health. FA leads to an increasing need for care, associated with an economic burden. Little is known about the impact of FA on daily lives and HRQoL. To fill that gap, we will assess patient-reported, psychosocial and economic outcomes using momentary data assessment via a mobile health application (app).

METHODS AND ANALYSIS

The PROFA Study is a prospective observational study. Patients with FA (n=200) will be recruited at six European study centres (Germany, France and Austria). We will interview patients at baseline in the study centre and subsequently assess the patients' health at home via mobile health app. Patients will self-report ataxia severity, HRQoL, speech and hearing disabilities, coping strategies and well-being, health services usage, adverse health events and productivity losses due to informal care on a daily to monthly basis on the app for 6 months. Our study aims to (1) validate measurements of HRQoL and psychosocial health, (2) assess the usability of the mobile health app, and (3) use descriptive and multivariate statistics to analyse patient-reported and economic outcomes and the interaction effects between these outcomes. Insights into the app's usability could be used for future studies using momentary data assessments to measure outcomes of patients with FA.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Ethics Committee of the University Medicine of Greifswald, (BB096/22a, 26 October 2022) and from all local ethics committees of the participating study sites. Findings of the study will be published in peer-reviewed journals, presented at relevant international/national congresses and disseminated to German and French Patient Advocacy Organizations.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT05943002); Pre-results.

A systematic review of disease prevalence, health-related quality of life, and economic outcomes associated with Friedreich's Ataxia

INTRODUCTION

Friedreich ataxia (FA) is a rare, inherited neuromuscular disease characterized by an early onset and progressive limb and gait ataxia. Currently, there are no approved treatments for FA. It is important to understand the burden of FA, including its extent and the most salient elements. The objective of this study is therefore to systematically review the literature regarding the aspects of prevalence, health-related quality of life (HRQoL), and economic outcomes that are associated with FA, and to subsequently identify relevant knowledge gaps.

METHODS

Three systematic literature reviews were conducted to assess publications regarding FA prevalence, HRQoL, and economic outcomes. Search strategies were implemented in MEDLINE (Ovid) and EMBASE databases; study selection and quality assessment were conducted using current best practices. For each review, study characteristics and findings were summarized.

RESULTS

A total of 36 studies were included. Review of prevalence studies (n = 22) indicated variation in the number of cases by region, and many regions were not represented at all. Regarding HRQoL (n = 12 studies), physical domains were consistently impacted, although findings regarding other domains and overall HRQoL were less clear. Cost studies (n = 2) encompassed 4 regions and revealed that costs related to the provision of care, including non-medical direct costs and indirect costs, accounted for the majority of FA-related costs.

DISCUSSION

Findings from this systematic review revealed several knowledge gaps that would preclude the conduct of a robust assessment of the benefits and outcomes associated with a disease-modifying FA therapy. Additional understanding regarding patient and caregiver HRQoL and costs is required.

Episodic Ataxia Type 1: Natural History and Effect on Quality of Life

Episodic ataxia type 1 (EA1) is a rare autosomal potassium channelopathy, due to mutations in KCNA1. Patients have childhood onset of intermittent attacks of ataxia, dizziness or imbalance. In order to quantify the natural history of EA1, its effect on quality of life and in preparation for future clinical trials, we set up an international multi-centre study of EA1. We recruited thirty-three participants with EA1: twenty-three completed 1-year follow-up and eighteen completed 2-year follow-up. There was very little accumulation of disability or impairment over the course of the 2 years of the study. The outcome measures of ataxia (SARA and functional rating of ataxia) and the activities of daily living scale were largely stable over time. Self-reported health-related quality of life (SF-36) scores were lower across all domains than controls, in keeping with a chronic condition. Physical subdomain scores appeared to deteriorate over time, which seems to be driven by the female participants in the study. This is an interesting finding and warrants further study. Attacks of EA1 reported by participants in real time via an interactive voice response system showed that symptoms were not stereotyped; however, attack duration and frequency was stable between individuals. This large prospective study is the first ever completed in subjects with EA1. We document the natural history of the disorder over 2 years. These data will enable the development of outcome measures for clinical trials of treatment.

The attitude of patients with progressive ataxias towards clinical trials

Background

The development of new therapies may rely on the conduct of human experimentation as well as later clinical trials of therapeutic interventions. Ethical considerations seek to protect the patient from risk but few have sought to ascertain the attitude to such risk of patients with progressive debilitating or terminal conditions, for which no mitigating or curative therapies exist. Such understanding is also important if recruitment is to be maximized. We therefore sought to define the motivations for and barriers to trial participation amongst patients with progressive ataxias, as well as their condition-specific trial preferences.

Methods

We conducted an online survey consisting of 29 questions covering four key domains (demographics, personal motivation, drug therapy and study design) relating to the design of clinical trials. Two major ataxia charities, Ataxia UK and the Friedreich’s Ataxia Research Alliance (FARA) sent the survey to their members. Responses were analysed by disease and by ambulatory status.

Results

Of 342 respondents, 204 reported a diagnosis of Friedreich’s ataxia (FRDA), 55 inherited cerebellar ataxia (CA) and 70 idiopathic CA. The most important symptoms to be addressed by a trial were considered to be balance problems and ambulation, although these were superseded by speech problems in wheelchair users. Common motivations for participation were potential benefits to self and others. Reasons for non-participation included concerns about side effects, and the burden and cost of travel. Financial reimbursement for expenses was reported to be likely to increase trial engagement, Phase two trials were the most popular to participate in, and the use of a placebo arm was seen as a disincentive. Across all disease subgroups, drug repurposing trials proved popular and just under 70% of participants would be prepared to undergo intrathecal drug administration.

Conclusions

Knowledge of motivations for and barriers to trial participation as well as the acceptability of investigations, time commitments and routes of drug administration should inform better, more patient focused trial design. This in turn may improve recruitment and retention of participants to future trials.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-02091-x.

Symptom burden of people with progressive ataxia, and its wider impact on their friends and relatives: a cross-sectional study

Background

Progressive ataxias are complex disorders that result in a wide variety of symptoms. Whilst we currently have a relatively good understanding of the symptom patterns associated with the various types of ataxia, and how these diseases progress over time, their impact on the person with ataxia is less well understood. In addition, little is known about how carers, friends and families are affected by them. This paper aims to provide preliminary information on the presence and impact of medical symptoms and day-to-day challenges on people with ataxia and their friends and relatives.

Method

Data were extracted from a survey by Ataxia UK for their members. The views of 366 people with ataxia and 52 friends and relatives are reported. Data were analysed for the entire groups, as well as for the three most common ataxia types represented in the sample, Friedreich's ataxia, inherited ataxia (excluding Friedreich's ataxia), and cerebellar ataxia of unknown cause.

Results

The survey confirmed the symptom patterns described in previous research, but further showed that the impact of these symptoms can vary across ataxia populations. Similar findings were observed for day-to-day challenges. Friends and relatives experienced similar challenges to people with ataxia, indicating that support provided has to consider those supporting people with ataxia as well as the patient. Respondents also highlighted limitations in terms of accessing support services, and not all services were able to cater fully to their specific needs.

Conclusion

This study begins to provide information that can be used in further research to explore the needs of people with ataxia and their carers, friends, and relatives. Such research will support treatment trial design, ensuring patients' needs are considered, help to tailor support services to their needs, and ensure health care professionals have the necessary skills to fully address them.

Correlation of Visual Quality of Life With Clinical and Visual Status in Friedreich Ataxia

BACKGROUND

The primary objective was to determine the association of patient-reported vision-specific quality of life to disease status and visual function in patients with Friedreich's ataxia (FRDA).

METHODS

Patients with FRDA were assessed with the 25-Item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25) along with measures of disease status (ataxia stage) and visual function (low- and high-contrast letter acuity scores). The relations of NEI-VFQ-25 scores to those for disease status and visual function were examined.

RESULTS

Scores for the NEI-VFQ-25 were lower in patients with FRDA (n = 99) compared with published disease-free controls, particularly reduced in a subgroup of FRDA patients with features of early onset, older age, and abnormal visual function.

CONCLUSIONS

The NEI-VFQ-25 captures the subjective component of visual function in patients with FRDA.

Rehabilitation for ataxia study: protocol for a randomised controlled trial of an outpatient and supported home-based physiotherapy programme for people with hereditary cerebellar ataxia

INTRODUCTION

Emerging evidence indicates that rehabilitation can improve ataxia, mobility and independence in everyday activities in individuals with hereditary cerebellar ataxia. However, with the rarity of the genetic ataxias and known recruitment challenges in rehabilitation trials, most studies have been underpowered, non-randomised or non-controlled. This study will be the first, appropriately powered randomised controlled trial to examine the efficacy of an outpatient and home-based rehabilitation programme on improving motor function for individuals with hereditary cerebellar ataxia.

METHODS AND ANALYSIS

This randomised, single-blind, parallel group trial will compare a 30-week rehabilitation programme to standard care in individuals with hereditary cerebellar ataxia. Eighty individuals with a hereditary cerebellar ataxia, aged 15 years and above, will be recruited. The rehabilitation programme will include 6 weeks of outpatient land and aquatic physiotherapy followed immediately by a 24- week home exercise programme supported with fortnightly physiotherapy sessions. Participants in the standard care group will be asked to continue their usual physical activity. The primary outcome will be the motor domain of the Functional Independence Measure. Secondary outcomes will measure the motor impairment related to ataxia, balance, quality of life and cost-effectiveness. Outcomes will be administered at baseline, 7 weeks, 18 weeks and 30 weeks by a physiotherapist blinded to group allocation. A repeated measures mixed-effects linear regression model will be used to analyse the effect of the treatment group for each of the dependent continuous variables. The primary efficacy analysis will follow the intention-to-treat principle.

ETHICS AND DISSEMINATION

The study has been approved by the Monash Health Human Research Ethics Committee (HREC/18/MonH/418) and the Human Research Ethics Committee of the Northern Territory Department of Health and Menzies School of Health Research (2019/3503). Results will be published in peer-reviewed journals, presented at national and/or international conferences and disseminated to Australian ataxia support groups.

TRIAL REGISTRATION NUMBER

ACTRN12618000908235.

Safety and feasibility of upper limb cardiopulmonary exercise test in Friedreich ataxia

Aims

To explore the feasibility of upper limbs cardiopulmonary exercise test (CPET) in Friedreich ataxia (FRDA) patients and to compare the results with sex, age, and body mass index (BMI) matched cohort of healthy controls (HC).

Methods and results

Cardiopulmonary exercise test was performed using an upper limbs cycle ergometer on fasting subjects. Peak oxygen uptake (peak VO2) was recorded as the mean value of VO2 during a 20 s period at the maximal effort of the test at an appropriate respiratory exchange rate. The ventilatory anaerobic threshold (AT) was detected by the use of the V-slope method. We performed echocardiography with an ultrasound system equipped with a 2.5 MHz multifrequency transducer for complete M-mode, two-dimensional, Doppler, and Tissue Doppler Imaging analyses. We studied 55 FRDA and 54 healthy matched controls (HC). Peak VO2 showed a significant 31% reduction in FRDA patients compared to HC (15.2 ± 5.7 vs. 22.0 ± 6.1 mL/kg/min; P &lt; 0.001). Peak workload was reduced by 41% in FRDA (42.9 ± 12.5 vs. 73.1 ± 21.2 W; P &lt; 0.001). In FRDA patients, peak VO2 is inversely correlated with the Scale for Assessment and Rating of Ataxia score, disease duration, and 9HPT performance, and directly correlated with activities of daily living. The AT occurred at 48% of peak workload time in FRDA patients and at 85% in HC (P &lt; 0.001).

Conclusions

Upper limb CPET is useful in the assessment of exercise tolerance and a possible tool to determine the functional severity of the mitochondrial oxidative defect in patients with FRDA. The cardiopulmonary exercise test is an ideal functional endpoint for Phases II and III trials through a simple, non-invasive, and safe exercise test.

Sexual function, intimate relationships and Friedreich ataxia

BACKGROUND

Sexual dysfunction (SD) is reported in neurological conditions similar to Friedreich ataxia (FRDA). Anecdotally individuals with FRDA report SD including erectile dysfunction and altered genital sensation. Understanding SD in FRDA assists health professionals identify SD issues and improve healthcare for individuals with FRDA.

OBJECTIVE

To quantify if, and to what extent, people with FRDA experience challenges with sexual function and intimate relationships as a result of primary (genital function), secondary (physical) and tertiary (psychosocial) dysfunction.

METHODS

An online purpose designed anonymous questionnaire explored SD and intimate relationships. Invitations to participate were sent to individuals with FRDA aged 18 years and over on the Ataxia UK and Friedreich Ataxia Research Alliance databases. Date collection occurred between January and July, 2017.

RESULTS

One-hundred-and-seventy-nine adults with FRDA participated, of which 107 reported current or previous sexual activity. Erectile dysfunction was reported in 57% (20/35) of males, inadequate vaginal lubrication interfering with sexual responsiveness was reported in 57.7% (26/45) of females, and 47% (51/107) reported reduced genital sensation. In addition, 88% (94/107) reported problems moving their body during sexual activity and 73% (78/107) reported reduced confidence about their sexuality due to FRDA. A significant negative relationship was shown between younger age of disease onset and SD.

CONCLUSION

This study confirmed FRDA impacts sexual functioning, sexual satisfaction and the capacity to form intimate relationships. Understanding the nature and extent of SD is critical to developing interventions and recommendations designed to enhance sexual function, sexuality, and intimate relationships for individuals with FRDA.

Cost of Cerebellar Ataxia in Hong Kong: A Retrospective Cost-of-Illness Analysis

Background: Cerebellar ataxia affects the coordination and balance of patients. The impact of this disease increases burden in patients, caregivers and society. Costs and the burden of this disease have not been investigated in Hong Kong.

Objectives: (1) To estimate the socioeconomic cost of cerebellar ataxia in Hong Kong for the base year 2019, (2) to assess the health-related quality of life (HRQoL) and severity of ataxia, and (3) to establish the correlation between the severity and cost of cerebellar ataxia and to examine the correlation between the severity of cerebellar ataxia and HRQoL.

Methods: A retrospective cross-sectional study was conducted amongst 31 patients with cerebellar ataxia. Cost-related data were obtained through self-reported questionnaires. The severity of ataxia was assessed using the Scale for Assessment and Rating of Ataxia, and HRQoL was assessed using the Short Form (36) Health Survey (SF-36). Pearson correlation was used for normally distributed data, whereas Spearman correlation was used otherwise.

Results: The mean severity of ataxia was 21 out of 40. The average direct and indirect costs of a patient with ataxia in 6 months were HKD 51,371 and HKD 93,855, respectively. The mean difference between the independent to minimally dependent in activities of daily living (ADL) group and the moderate to maximally dependent in ADL group for direct and indirect costs was HKD 33,829 and HKD 51,444, respectively. Significant expenditure was related to production lost (42%), caregiver salary (17%), and in-patient care (16%). The physical functioning (r = −0.58) and general health (r = −0.41) of SF-36 were negatively correlated with disease severity (p < 0.05). A significant, positive correlation was found between disease severity and direct cost (Spearman's rho = 0.39) and the cost of hiring a caregiver (Spearman's rho = 0.43).

Conclusion: The mean cost for 6 months for patients with cerebellar ataxia in Hong Kong is HKD 146,832. Additional support, including employment, access to specialist consultants, informal home care and community participation, are some areas that should be addressed. Future study on a larger population with a prospective design is necessary to confirm the aforementioned claims.

Health related quality of life in Friedreich Ataxia in a large heterogeneous cohort

INTRODUCTION

This study assessed the Health Related Quality of Life (HRQOL) of individuals with Friedreich Ataxia (FRDA) through responses to HRQOL questionnaires.

METHODS

The SF-36, a generic HRQOL instrument, and symptom specific scales examining vision, fatigue, pain and bladder function were administered to individuals with FRDA and analyzed by comparison with disease features. Multiple linear regression models were used to study independent effects of genetic severity and age. Assessments were performed at baseline then intermittently after that.

RESULTS

Subjects were on average young adults. For the SF36, the subscale with the lowest HRQOL score was the physical function scale, while the emotional well-being score was the highest. The physical function scale correlated with age of onset, duration, and subject age. In assessment of symptom specific scales, bladder control scores (BLCS) correlated with duration and age, while impact of visual impairment scores (IVIS) correlated with duration. In linear regression models, the BLCS, Pain Effect Score, and IVIS scores were predicted by age and GAA length; modified fatigue impact scale scores were predicted only by GAA length. Physical function and role limitation scores declined over time. No change was seen over time in other SF-36 subscores. Symptom specific scales also worsened over time, most notably the IVIS and BLCS.

CONCLUSION

The SF-36 and symptom specific scales capture dysfunction in FRDA in a manner that reflects disease status. HRQOL dysfunction was greatest on physically related scales; such scales correlated with disease duration, indicating that they worsen with progressing disease.

Health-related quality of life and depressive symptoms in Friedreich ataxia

PURPOSE

Friedreich ataxia (FRDA) is a chronic, progressive and highly disabling cerebellar degenerative disease. Despite this, little attention has been paid to the health-related quality of life (HRQOL) in this disease. The aim of the present study was to assess FRDA patients' perception of HRQOL and to determine the influence of depression, and demographic and clinical variables.

METHOD

The sample consisted of 62 patients with genetically confirmed FRDA. The SF-36 Health Survey was used to assess HRQOL. Depressive symptoms were evaluated with the Beck Depression Inventory-II.

RESULTS

FRDA patients' mean scores were significantly lower than the values for the Spanish population in all SF36 dimensions. Average z scores ranged from - 5.5 in physical functioning to - 0.48 in mental health. Age and clinical variables were significant predictors of HRQOL in only several dimensions, whereas BDI scores were able to predict a significant percentage of variance in all SF36 dimensions, except physical functioning.

CONCLUSIONS

Our study demonstrates the high impact of Friedreich ataxia on quality of life. This impact does not only occur in those aspects most related to motor disability but it is also present in non-motor dimensions. Depressive symptomatology is the most relevant variable for predicting quality of life.

Open-label pilot study of oral methylprednisolone for the treatment of patients with friedreich ataxia

INTRODUCTION

In this study we assessed the effect of methylprednisolone on safety, tolerability, and ability in Friedreich ataxia (FRDA).

METHODS

The study was an open-label trial of pulse methylprednisolone on 11 participants with FRDA. All participants followed a 28-day treatment cycle, repeated 7 times. Patients were assessed with the timed 25-foot walk (T25FW), 1-minute walk (1MW), the Friedreich Ataxia Rating Scale (FARS), and the 9-hole peg test (9HPT). Efficacy was tested by comparing baseline and week 26 visits, separated into adult and pediatric groups.

RESULTS

In comparisons of participants' baseline and week 26 visits, only the pediatric cohort's 1MW score showed change (P < 0.05). The T25FW, the primary outcome measure, did not change significantly.

DISCUSSION

Pediatric participants improved their gait distance in the 1MW, but did not significantly improve in other measures in this overall negative study. Methylprednisolone was generally well tolerated, suggesting that it may be useful for ambulatory children with FRDA if benefit is found with further study.

Randomized, double-blind, placebo-controlled study of interferon-γ 1b in Friedreich Ataxia

Objective

In vitro, in vivo, and open-label studies suggest that interferon gamma (IFN-γ 1b) may improve clinical features in Friedreich Ataxia through an increase in frataxin levels. The present study evaluates the efficacy and safety of IFN-γ 1b in the treatment of Friedreich Ataxia through a double-blind, multicenter, placebo-controlled trial.

Methods

Ninety-two subjects with FRDA between 10 and 25 years of age were enrolled. Subjects received either IFN-γ 1b or placebo for 6 months. The primary outcome measure was the modified Friedreich Ataxia Rating Scale (mFARS).

Results

No difference was noted between the groups after 6 months of treatment in the mFARS or secondary outcome measures. No change was noted in buccal cell or whole blood frataxin levels. However, during an open-label extension period, subjects had a more stable course than expected based on natural history data.

Conclusions

This study provides no direct evidence for a beneficial effect of IFN-γ1b in FRDA. The modest stabilization compared to natural history data leaves open the possibility that longer studies may demonstrate benefit.

Longitudinal analysis of contrast acuity in Friedreich ataxia

Objective

To determine the natural history of contrast acuity in Friedreich ataxia.

Methods

In the Friedreich Ataxia–Clinical Outcome Measures Study, participants (n = 764) underwent binocular high- and low-contrast visual acuity testing at annual study visits. Mixed-effects linear regression was used to model visual acuity as a function of time, with random intercepts and slopes to account for intraindividual correlation of repeated measurements. A time-varying covariate was used to adjust for diabetes, and interaction terms were used to assess for effect modification by GAA repeat length, disease duration, and other variables.

Results

Across a median of 4.4 years of follow-up, visual acuity decreased significantly at 100% contrast (−0.37 letters/y, 95% confidence interval [CI]: −0.52 to −0.21), 2.5% contrast (−0.81 letters/year, 95% CI: −0.99 to −0.65), and 1.25% contrast (−1.12 letters/y, 95% CI: −1.29 to −0.96 letters/year). There was a significant interaction between time and GAA repeat length such that the rate of decrease in visual acuity was greater for patients with higher GAA repeat lengths at 2.5% contrast (p = 0.018) and 1.25% contrast (p = 0.043) but not 100% contrast. There was no effect modification by age at onset after adjusting for GAA repeat length.

Conclusions

Low-contrast visual acuity decreases linearly over time in Friedreich ataxia, and the rate of decrease is greater at higher GAA repeat lengths. Contrast sensitivity has the potential to serve as a biomarker and surrogate outcome in future studies of Friedreich ataxia.

Impact of Mobility Device Use on Quality of Life in Children With Friedreich Ataxia

OBJECTIVE

To determine how mobility device use impacts quality of life in children with Friedreich ataxia.

STUDY DESIGN

Data from 111 pediatric patients with genetically confirmed Friedreich ataxia were collected from a prospective natural history study utilizing standardized clinical evaluations, including health-related quality of life using the Pediatric Quality of Life Inventory (PedsQL) 4.0 Generic Core Module.

RESULTS

Mobility device use was associated with worse mean PedsQL total, physical, emotional, social, and academic subscores, after adjusting for gender, age of disease onset, and Friedreich Ataxia Rating Scale score. The magnitude of the difference was greatest for the physical subscore (-19.5 points, 95% CI = -30.00, -8.99, P < .001) and least for the emotional subscore (-10.61 points, 95% CI = -20.21, -1.02, P = .03). Transition to or between mobility devices trended toward worse physical subscore (-16.20 points, 95% CI = -32.07, -0.33, P = .05).

CONCLUSIONS

Mobility device use is associated with significant worsening of all domains of quality of life in children with Friedreich ataxia.

A longitudinal study of the SF-36 version 2 in Friedreich ataxia

OBJECTIVES

The Medical Outcomes Study 36 item Short-Form Health Survey (SF-36) is one of the most commonly used patient reported outcome measure. This study aimed to examine the relationship between SF-36 version 2 (SF-36V2) summary scores and Friedreich ataxia (FRDA) clinical characteristics, and to investigate the responsiveness of the scale, in comparison with the Friedreich Ataxia Rating Scale (FARS), over 1, 2 and 3 years.

MATERIALS AND METHODS

Descriptive statistics were used to examine the characteristics of the cohort at baseline and years 1, 2 and 3. Correlations between FRDA clinical characteristics and SF-36V2 summary scores were reported. Responsiveness was measured using paired t tests.

RESULTS

We found significant correlations between the physical component summary (PCS) of the SF-36V2 and various FRDA clinical parameters but none for the mental component summary. No significant changes in the SF-36V2 were seen over 1 or 2 years; however, PCS scores at Year 3 were significantly lower than at baseline (-3.3, SD [7.6], P=.01). FARS scores were found to be significantly greater at Years 1, 2 and 3 when compared to baseline.

CONCLUSIONS

Our findings suggest that despite physical decline, individuals with FRDA have relatively stable mental well-being. This study demonstrates that the SF-36V2 is unlikely to be a useful tool for identifying clinical change in FRDA therapeutic trials.

Mitochondrial capacity, muscle endurance, and low energy in friedreich ataxia

INTRODUCTION

In this study we noninvasively evaluated skeletal muscle mitochondrial capacity, muscle-specific endurance, and energy/fatigue feelings in persons with Friedreich ataxia (FRDA) and able-bodied controls (AB).

METHODS

Forearm mitochondrial capacity was measured in FRDA (n = 16) and AB (n = 10) study participants using the rate of recovery of oxygen consumption after electrical stimulation with near-infrared spectroscopy. Mechanomyography (MMG) assessed muscle endurance after electrical stimulation for 3 minutes at 2 Hz, 4 Hz, and 6 Hz. Validated scales assessed disease severity and energy/fatigue feelings.

RESULTS

Groups did not differ in mitochondrial capacity (FRDA and AB: 1.8 ± 0.3 L/min). The difference in muscle endurance at 6 Hz was lower by 19.2% in the FRDA group (group effect: P < 0.001). Feelings of physical energy were 34% lower in FRDA group. In FDRA muscle, endurance was positively related to mitochondrial capacity (r = 0.59, P = 0.03), and disease severity was negatively related to mitochondrial capacity (r = -0.55, P = 0.04) and muscle endurance (r = -0.60, P = 0.01).

CONCLUSION

Non-invasive measures of skeletal muscle mitochondrial capacity and muscle-specific endurance are useful in monitoring FRDA. Muscle Nerve 56: 773-779, 2017.

Health-related quality of life in patients with spinocerebellar ataxia

INTRODUCTION

The progressive deterioration of patients with spinocerebellar ataxia (SCA) has a major impact on their health-related quality of life (HRQOL). This study evaluates HRQOL in a sample of patients diagnosed with SCA and aims to estimate the predictive ability of a set of sociodemographic variables for the different dimensions of the General Health Questionnaire.

METHODS

A total of 80 patients diagnosed with SCA were assessed using a sociodemographic questionnaire and the SF-36 General Health Questionnaire. The sociodemographic variables studied were sex, age, presence of a carer, employment status, and time elapsed from diagnosis of the disease.

RESULTS

The 8 subscales of the SF-36 show positive and significant correlations to one another. Mean scores obtained on each SF-36 subscale differ between women and men, although this difference is significant only on the general health subscale, with men scoring higher than women. We found significant age differences on the vitality and social function subscales, with higher scores among younger patients (< 34 years). The variable 'presence of a carer' accounts for most of the total variance of the questionnaire.

CONCLUSIONS

The SF-36 is a valid and useful instrument for evaluating HRQOL in patients diagnosed with SCA. Presence of a carer seems to be a determinant of self-perceived quality of life in these patients.

A longitudinal study of the Friedreich Ataxia Impact Scale

BACKGROUND

Quality of life in Friedreich ataxia (FRDA) has been explored using various generic health status measurement tools, most commonly the Short Form Health Survey Version 2 (SF-36v2). The tool did not address many specific issues related to disease impact in people with FRDA. The Friedreich Ataxia Impact Scale (FAIS) was developed to examine clinically relevant areas in FRDA. The aims of the current study were to assess the relationship between the FAIS and clinical characteristics of FRDA, as well as to determine the responsiveness of the FAIS to change over one and two years.

METHODS

One hundred and four individuals with FRDA, homozygous for the GAA expansion in intron 1 of FXN, completed the FAIS at baseline. Seventy individuals completed the FAIS again 12 months later and 49 completed the FAIS at 24 months. Clinical parameters and neurologic scales (Friedreich Ataxia Rating Scale (FARS)) were also recorded.

RESULTS

The total FARS score, onset age and disease duration correlated significantly with FAIS subscales measuring symptoms and physical functioning. The physical and mental summary measures of the SF-36 V2 also correlated well with the FAIS subscales. Speech was the only subscale that demonstrated significant change over one and two years.

CONCLUSIONS

The FAIS provides valuable insight into the perspective of individuals with FRDA on their health status, and is an important measure of morbidity. It has, however, limited responsiveness to change and its use in intervention studies is questionable.

Biological and clinical characteristics of the European Friedreich's Ataxia Consortium for Translational Studies (EFACTS) cohort: a cross-sectional analysis of baseline data

BACKGROUND

Friedreich's ataxia is a rare autosomal recessive neurodegenerative disorder. Here we report cross-sectional baseline data to establish the biological and clinical characteristics for a prospective, international, European Friedreich's ataxia database registry.

METHODS

Within the European Friedreich's Ataxia Consortium for Translational Studies (EFACTS) framework, we assessed a cohort of patients with genetically confirmed Friedreich's ataxia. The primary outcome measure was the Scale for the Assessment and Rating of Ataxia (SARA) and secondary outcome measures were the Inventory of Non-Ataxia Signs (INAS), the performance-based coordination test Spinocerebellar Ataxia Functional Index (SCAFI), the neurocognitive phonemic verbal fluency test, and two quality-of-life measures: the activities of daily living (ADL) part of the Friedreich's Ataxia Rating Scale and EQ-5D. The Friedreich's ataxia cohort was subdivided into three groups: early disease onset (≤14 years), intermediate onset (15-24 years), and late onset (≥25 years), which were compared for clinical characteristics and outcome measures. We used linear regression analysis to estimate the annual decline of clinical outcome measures based on disease duration. This study is registered with ClinicalTrials.gov, number NCT02069509.

FINDINGS

We enrolled 592 patients with genetically confirmed Friedreich's ataxia between Sept 15, 2010, and April 30, 2013, at 11 sites in seven European countries. Age of disease onset was inversely correlated with the number of GAA repeats in the frataxin (FXN) gene: every 100 GAA repeats on the smaller repeat allele was associated with a 2·3 year (SE 0·2) earlier onset. Regression analyses showed significant estimated annual worsening of SARA (regression coefficient 0·86 points [SE 0·05], INAS (0·14 points [0·01]), SCAFI Z scores (-0·09 [0·01]), verbal fluency (-0·34 words [0·07]), and ADL (0·64 points [0·04]) during the first 25 years of disease; the regression slope for health-related quality-of-life state from EQ-5D was not significant (-0·33 points [0·18]). For SARA, the predicted annual rate of worsening was significantly higher in early-onset patients (n=354; 1·04 points [0·13]) and intermediate-onset patients (n=137; 1·17 points [0·22]) than in late-onset patients (n=100; 0·56 points [0·10]).

INTERPRETATION

The results of this cross-sectional baseline analysis of the EFACTS cohort suggest that earlier disease onset is associated with larger numbers of GAA repeats and more rapid disease progression. The differential estimated progression of ataxia symptoms related to age of onset have implications for the design of clinical trials in Friedreich's ataxia, for which SARA might be the most suitable measure to monitor disease progression.

FUNDING

European Commission.

Sleep and sleep disorders in rare hereditary diseases: a reminder for the pediatrician, pediatric and adult neurologist, general practitioner, and sleep specialist

Although sleep abnormalities in general and sleep-related breathing disorders (SBD) in particular are quite common in healthy children; their presence is notably under-recognized. Impaired sleep is a frequent problem in subjects with inborn errors of metabolism as well as in a variety of genetic disorders; however, they are commonly either missed or underestimated. Moreover, the complex clinical presentation and the frequently life-threatening symptoms are so overwhelming that sleep and its quality may be easily dismissed. Even centers, which specialize in rare genetic-metabolic disorders, are expected to see only few patients with a particular syndrome, a fact that significantly contributes to the under-diagnosis and treatment of impaired sleep in this particular population. Many of those patients suffer from reduced life quality associated with a variable degree of cognitive impairment, which may be worsened by poor sleep and abnormal ventilation during sleep, abnormalities which can be alleviated by proper treatment. Even when such problems are detected, there is a paucity of publications on sleep and breathing characteristics of such patients that the treating physician can refer to. In the present paper, we provide an overview of sleep and breathing characteristics in a number of rare genetic–metabolic disorders with the hope that it will serve as a reminder for the medical professional to look for possible impaired sleep and SBD in their patients and when present to apply the appropriate evaluation and treatment options.

Episodic ataxia type 1: clinical characterization, quality of life and genotype-phenotype correlation

Episodic ataxia type 1 is considered a rare neuronal ion channel disorder characterized by brief attacks of unsteadiness and dizziness with persistent myokymia. To characterize the natural history, develop outcome measures for future clinical trials, and correlate genotype with phenotype, we undertook an international, prospective, cross-sectional study. Thirty-nine individuals (51% male) were enrolled: median age 37 years (range 15-65 years). We identified 10 different pathogenic point mutations in KCNA1 that accounted for the genetic basis of 85% of the cohort. Participants with KCNA1 mutations were more likely to have a positive family history. Analysis of the total cohort showed that the first episode of ataxia occurred before age 20 in all but one patient, with an average age of onset of 7.9 years. Physical exertion, emotional stress and environmental temperature were the most common triggers for attacks. Attack frequency ranged from daily to monthly, even with the same KCNA1 genotype. Average attack duration was in the order of minutes. Ten participants (26%) developed permanent cerebellar signs, which were related to disease duration. The average Scale for the Assessment and Rating of Ataxia score (SARA, a standardized measure of cerebellar dysfunction on clinical examination, scores range from 0-40) was an average of 3.15 for all participants (range 0-14), but was only 2 in those with isolated episodic ataxia compared with 7.7 in those with progressive cerebellar ataxia in addition to episodic ataxia. Thirty-seven participants completed the SF-36, a quality of life survey; all eight domain norm-based average scores (mean=50) were below normal with mental health being the lowest (41.3) in those with mutation positive episodic ataxia type 1. Scores on SF-36 correlated negatively with attack frequency. Of the 39 participants in the study, 33 harboured mutations in KCNA1 whereas the remaining six had no mutation identified. Episodic ataxia type 1 phenocopies have not been described previously and we report their clinical features, which appear to be different to those with a KCNA1 mutation. This large prospective study of both genetically confirmed episodic ataxia type 1 and episodic ataxia type 1 phenocopies provides detailed baseline characteristics of these disorders and their impact on participants. We found that attacks had a significant effect on quality of life. Unlike previous studies, we found that a significant number of individuals with genetically confirmed episodic ataxia type 1 (21%) had accumulated persistent cerebellar symptoms and signs. These data will enable the development of outcome measures for clinical trials of treatment.

Neuroanatomical correlates of depression in Friedreich's ataxia: a voxel-based morphometry study

Affective disorders have been increasingly recognized in neurodegenerative diseases and often result in poor quality of life. However, the frequency, clinical relevance, and anatomical substrate of depression in Friedreich's ataxia were not yet evaluated. We assessed 22 patients with Friedreich's ataxia for major depression using Beck Depression Inventory and cerebral 3 T MRI scans. We then employed whole-brain voxel-based morphometry analyses on volumetric T1 datasets to compare tissue loss between patients with and without major depression. Patients (36.3 %) fulfilled criteria for major depression (8/22). Mean Beck Depression Inventory (BDI) score was 9.63 ± 8.95 and the depressive group had significantly higher score compared to non-depressive group (18.5 ± 8.6 vs 4.4 ± 2.9, p < 0.001). There was no correlation between Beck Depression Inventory score and age of patients, ataxia severity, age at onset, or duration of the disease. The comparison between patient groups found no significant differences of white matter volumes. In contrast, we found reduction of gray matter volumes in the depressive group in medial and orbital region of frontal lobe and anterior cingulate gyri (p < 0.001). Regression analyses have shown that BDI scores were inversely correlated with gray matter volume at right superior frontal gyrus. Major depression is frequent in Friedreich's ataxia and possibly under recognized. Our results strongly suggest that this may not be a simply reactive phenomenon, but rather associated to structural abnormalities.

Clinical features of Friedreich's ataxia: classical and atypical phenotypes

One hundred and fifty years since Nikolaus Friedreich's first description of the degenerative ataxic syndrome which bears his name, his description remains at the core of the classical clinical phenotype of gait and limb ataxia, poor balance and coordination, leg weakness, sensory loss, areflexia, impaired walking, dysarthria, dysphagia, eye movement abnormalities, scoliosis, foot deformities, cardiomyopathy and diabetes. Onset is typically around puberty with slow progression and shortened life-span often related to cardiac complications. Inheritance is autosomal recessive with the vast majority of cases showing an unstable intronic GAA expansion in both alleles of the frataxin gene on chromosome 9q13. A small number of cases are caused by a compound heterozygous expansion with a point mutation or deletion. Understanding of the underlying molecular biology has enabled identification of atypical phenotypes with late onset, or atypical features such as retained reflexes. Late-onset cases tend to have slower progression and are associated with smaller GAA expansions. Early-onset cases tend to have more rapid progression and a higher frequency of non-neurological features such as diabetes, cardiomyopathy, scoliosis and pes cavus. Compound heterozygotes, including those with large deletions, often have atypical features. In this paper, we review the classical and atypical clinical phenotypes of Friedreich's ataxia.

Excessive motor overflow reveals abnormal inter-hemispheric connectivity in Friedreich ataxia

This study sought to characterise force variability and motor overflow in 12 individuals with Friedreich ataxia (FRDA) and 12 age- and gender-matched controls. Participants performed a finger-pressing task by exerting 30 and 70 % of their maximum finger force using the index finger of the right and left hand. Control of force production was measured as force variability, while any involuntary movements occurring on the finger of the other, passive hand, was measured as motor overflow. Significantly greater force variability in individuals with FRDA compared with controls is indicative of cortico-cerebellar disruption affecting motor control. Meanwhile, significantly greater motor overflow in this group provides the first evidence of possible abnormal inter-hemispheric activity that may be attributable to asymmetrical neuronal loss in the dentate nucleus. Overall, this study demonstrated a differential engagement in the underlying default processes of the motor system in FRDA.

Common data elements for clinical research in Friedreich's ataxia

To reduce study start-up time, increase data sharing, and assist investigators conducting clinical studies, the National Institute of Neurological Disorders and Stroke embarked on an initiative to create common data elements for neuroscience clinical research. The Common Data Element Team developed general common data elements, which are commonly collected in clinical studies regardless of therapeutic area, such as demographics. In the present project, we applied such approaches to data collection in Friedreich's ataxia (FRDA), a neurological disorder that involves multiple organ systems. To develop FRDA common data elements, FRDA experts formed a working group and subgroups to define elements in the following: ataxia and performance measures; biomarkers; cardiac and other clinical outcomes; and demographics, laboratory tests, and medical history. The basic development process included identification of international experts in FRDA clinical research, meeting by teleconference to develop a draft of standardized common data elements recommendations, vetting of recommendations across the subgroups, and dissemination of recommendations to the research community for public comment. The full recommendations were published online in September 2011 at http://www.commondataelements.ninds.nih.gov/FA.aspx. The subgroups' recommendations are classified as core, supplemental, or exploratory. Template case report forms were created for many of the core tests. The present set of data elements should ideally lead to decreased initiation time for clinical research studies and greater ability to compare and analyze data across studies. Their incorporation into new, ongoing studies will be assessed in an ongoing fashion to define their utility in FRDA.

A review of Friedreich ataxia clinical trial results

There are now 21 agents or classes of therapeutic agents in the Friedreich ataxia research pipeline (http://www.curefa.org/pipeline.html) that have been developed in the 15 years since the discovery of the frataxin gene, with the ongoing characterization of its mutations and the resulting molecular pathology. Twenty-four studies are currently posted on ClinicalTrials.gov. Twenty-seven works discussing the results of clinical trials in Friedreich ataxia have been published. In 2010, 42 public (National Institutes of Health) and private (Friedreich Ataxia Research Alliance, Muscular Dystrophy Association, and National Ataxia Foundation) grants were funded for translational and clinical research in Friedreich ataxia. Millions of dollars from public, private, and industry-based initiatives have been dedicated to research in Friedreich ataxia therapeutics. Despite this vigorous international effort, there is as yet no proven disease-modifying therapy for Friedreich ataxia.

Fatigue in spinocerebellar ataxia: patient self-assessment of an early and disabling symptom

OBJECTIVE

To identify the prevalence and severity of fatigue and predicting factors for severe fatigue in autosomal dominant spinocerebellar ataxia (SCA).

METHODS

We studied a cross-section of 123 patients with SCA. Six functional scales were used in a self-assessment: the Fatigue Severity Scale (FSS); the Beck Depression Inventory (BDI); the Rotterdam Handicap Scale (RHS); the Short Form-36 health survey, distinguishing a norm-based physical and mental component score (Nb-PCS and Nb-MCS); the Pittsburgh Sleep Quality Index (PSQI); and the Epworth Sleepiness Scale (ESS). A subset of 58 patients was clinically evaluated, measuring severity of ataxia with the Scale for the Assessment and Rating of Ataxia and cognitive functioning with the Mini-Mental State Examination.

RESULTS

Severe fatigue (FSS ≥5) was present in 69% of patients and FSS value correlated with the scores on RHS, Nb-PCS, Nb-MCS, BDI, PSQI, and ESS. There was no relation with disease duration, gender, or medication use. Multivariate analysis revealed that Nb-PCS and BDI were the best independent predictors for severe fatigue. Interestingly, the presence of visual symptoms was related to FSS value in the clinically evaluated subgroup.

CONCLUSION

Fatigue is a severe and disabling symptom in adult patients with SCA, even early in the course of disease. Physical functioning and depression are the strongest predictors of fatigue. In treatment strategies, all treatable factors for fatigue should be addressed, especially depression, visual symptoms, and sleeping disorders.

Quality of life in rare genetic conditions: a systematic review of the literature

Quality of life (QoL) refers to an individual's sense of overall well-being encompassing physical, psychological, emotional, social, and spiritual dimensions. Although genetics healthcare providers strive to promote patient well-being, and the term QoL is often invoked to refer to this outcome, there is lack of clarity as to what actually constitutes QoL from the patient's perspective. This systematic literature review aims to summarize and integrate research findings to help elucidate how healthcare providers can more effectively enhance the QoL of patients affected with rare genetic conditions. Eligible studies were those that measured QoL as a primary outcome variable using a validated, multi-dimensional scale. Detailed criteria were used to rate quality of design, methodology, and analytic rigor. Fifty-eight studies were selected for inclusion in the review, and a narrative synthesis of the data was performed. A central theme emerging from the literature is that, although genetic conditions have the potential to have significant negative consequences for individuals' lives, having a genetic condition does not necessarily entail poor QoL. Evidence demonstrates that factors beyond the physical manifestations of the disease, such as psychological well-being, coping, and illness perceptions, influence QoL and may serve as potent targets for intervention. The field of research on QoL in rare genetic conditions will be advanced by uniting around a clear conceptualization of QoL and using more rigorous methodology with comprehensive measures of global QoL.

Health-related quality of life in children with Friedreich ataxia

The use of health-related quality of life scales as outcome measures in clinical trials is increasing. Although such measures have been validated in adults with Friedreich ataxia, they have not been studied in children with this disorder. The health-related quality of life of children with Friedreich ataxia was assessed using the PedsQL 4.0 Generic Core Module and Multidimensional Fatigue Scale. The scores from the Friedreich ataxia cohort were compared to those of control groups (children without a chronic disease). Minimal missing responses support the feasibility of using the PedsQL 4.0 in the Friedreich ataxia population. The scales demonstrated internal consistency, and concordance was observed between child and proxy scores. Children with Friedreich ataxia and their proxies reported lower health-related quality of life than did controls in the Core and Fatigue scales. A modest relationship was seen between markers of disease status and health-related quality of life, providing support for the idea that children with Friedreich ataxia have a lower health-related quality of life than those without a chronic disease. Additional studies are needed to examine the relationship between health-related quality of life and disease markers and to further establish the validity of the PedsQL 4.0 in this population.

Intermediate-dose idebenone and quality of life in Friedreich ataxia

Idebenone has been used as therapy for Friedreich ataxia for more than a decade. Although several studies have assessed the influence of therapy on neurologic or cardiac function, there is a paucity of data surrounding patient-reported outcome measures. In an observational study of the effect of intermediate-dose idebenone (20 mg/kg per day) on quality of life and neurologic function measures, seven patients with Friedreich ataxia were assessed using the Pediatric Quality of Life Inventory, the International Cooperative Ataxia Rating Scale, and an Activities of Daily Living Scale before initiation of idebenone therapy and after 1 year of therapy. Physical scores on the Pediatric Quality of Life Inventory were universally worse after 1 year, and correlated with decreased activities of daily living scores. Despite worsening physical scores, there was a trend toward improved total, emotional, social, and school components of quality of life scores after 1 year of idebenone therapy. There was no statistically significant change in Pediatric Quality of Life Inventory scores between baseline and 1 year of idebenone therapy. Functional ability, as measured by activities of daily living scores, appeared to have the most influence on the perception of physical quality of life, which may be important in planning future therapeutic trials.

Evaluating the progression of Friedreich ataxia and its treatment

Friedreich ataxia is characterised by slowly progressive neurodegeneration and cardiomyopathy. Currently, no treatments have been proven to delay, prevent, or reverse the inexorable decline that occurs in this condition; however, several pharmaceutical agents are undergoing clinical assessment. Because initial beneficial therapies are likely to slow disease progression rather than reverse morbidity, the need for accurate measurement tools that will detect such subtle benefits is critical. The impact of Friedreich ataxia on the nervous system has been assessed largely through the use of rating scales and functional composite measures, and a number of patient reported outcome measures in Friedreich ataxia have been studied. However, on the basis of published reports on the performance of these measures, none clearly stands out as the best for use in clinical trials. Refinement of existing tools and development of new tools will be needed to maximise the chance of detecting small but clinically significant benefits of therapeutic agents in patients with Friedreich ataxia.