Rating scales used to succinctly describe the severity of Friedreich’s ataxia and the impact on patients’ quality of life have a tradeoff between being comprehensive enough to adequately describe patient symptoms and overly detailed and complicated. A new study published in Journal of the Neurological Sciences compared two scales, the Friedreich Ataxia Impact Scale (FAIS) and the Short Form Health Survey Version 2 (SF-36v2), to determine a relationship between scaled scores and patient characteristics over time.
“The total Friedreich Ataxia Rating Scale (FARS) score, onset age, and disease duration correlated significantly with FAIS subscales measuring symptoms and physical functioning,” stated the authors of the study, “A Longitudinal Study of the Friedreich’s Ataxia Impact Scale.” “The physical and mental summary measures of the SF-36 V2 also correlated well with the FAIS subscales.”
Over 100 patients with Friedreich’s ataxia caused by two copies of the GAA expansion in intron 1 of FXN (the gene encoding frataxin protein) were included in the study. Patients completed the FAIS at the beginning of the study. At the midpoint of the study (12 months), 70 individuals were reevaluated, and at the end of the study (24 months), 49 individuals provided final data.
Looking at the scores, it appears that the scales could give an indication of disease severity and patient health status. However, minimal change over time was detected by the scales, prompting the researchers to question their use during intervention studies.
To complete the FAIS, eight areas are measured: speech, upper limb function, lower limb function, body movement, complex tasks, isolation, mood, and self perception. These areas contain a total of 126 items to create the FAIS. Similarly, in the SF-36v2, eight scales are used: physical function, role-physical, bodily pain, general health, vitality, social function, role-emotional, and mental health. Each of these areas contains multiple items, resulting in 36 items used to describe clinical characteristics of Friedreich’s ataxia. Clustering similar groups together, the SF-36v2 provides two summary measures: physical health and mental health.
By evaluating the FAIS, researchers drew insight on describing the health status of patients with Friedreich’s ataxia. Defining these measures may be useful in creating a single “language” to use when discussing clinical trials for Friedreich’s ataxia and general treatment options for patients.