In the accompanying article “The Spectrum of Motor and Non-Motor Symptoms of Adult-Onset Genetic and Sporadic Cerebellar Ataxia,” Abo AlSamh et al. describe findings from a retrospective review of a large adult-onset ataxia patient population from a Canadian center. ^{Reference Abo AlSamh, Woo, Bruno, Karnik and Furtado1} While non-ataxia motor symptoms have been previously described in patients from Canadian centers, ^{Reference Alshimemeri, Abo Alsamh and Zhou2} this is the first description of non-motor symptoms (NMS) in Canadian patients with ataxia. This article adds to the growing literature on this subject while also highlighting the prevalence of NMS in this population.

NMS are well recognized in other movement disorders including Parkinson disease, tic disorders and dystonia ^{Reference Klingelhoefer, Chaudhuri and Kamm3} but have been much less studied in patients with ataxia. A systematic review in 2022 found that NMS were common but under-recognized and under-treated in hereditary ataxias. ^{Reference Malek, Makawita, Al-Sami, Aslanyan and de Silva4}

Abo AlSamh et al. reported on all patients presenting with ataxia – both hereditary and sporadic adult-onset ataxias (SAOA) and found that NMS were common for all causes of ataxia. Cognitive impairment, mood disorders and pain were the most common NMS in this population, with sleep disorders and bowel and bladder dysfunction also present. The presence of NMS was determined via clinical documentation and not systematically acquired, suggesting the actual frequency of NMS is higher. This study population unfortunately predated the discovery of important genetic causes of ataxia including SCA27B, a patient group most likely included in the SAOA population. This does not detract from the overall result of the high prevalence of NMS found in all patients with ataxia.

One area requiring more investigation is whether NMS are due to changes in cerebellar circuitry and are an inherent part of the disease process or secondary to the effects of living with a disabling disorder. Cognitive dysfunction in hereditary ataxias has been linked to changes in cortico-cerebellar circuitry and is most likely caused by the underlying disease process. ^{Reference Vieira, Tenório and Handam5} It is probable that the cause of NMS in patients with ataxia is multifactorial and may vary based on the specific ataxia diagnosis.

It will be beneficial for future studies and ataxia registries to prospectively gather information on NMS in all patients with ataxia. This study highlights the importance of routine screening for NMS during clinical encounters for patients. It is crucial to ensure that future clinical practice incorporates the questioning and treatment of NMS to improve the quality of life for all patients with ataxia.