Cognitive impairment in amyotrophic lateral sclerosis: the hidden challenges

Abstract

Motor neurone disease (MND) or amyotrophic lateral sclerosis (ALS) is a devastating, neurological condition. It is a progressive disease that attacks the nerves in the brain and spinal cord, leading to progressive weakness and wasting of muscles. This can lead to difficulties in walking, speech, eating, drinking and breathing (MND Association, 2016). MND is a rapidly progressive disease with death usually occurring 2–5 years from onset of first symptom. Diagnosis is usually made around 12 months from first symptom, with the diagnosis typically being made around the midpoint (50% of total disease duration elapsed) of the disease pathway (Mitchell et al, 2010). Although it is progressive, the rate and nature of progression can be unpredictable, with damage to affected areas occurring in no specific order (MND Association, 2016). The incidence of MND in England, Wales and Northern Ireland is approximately 1–2 cases per 100 000 people per year, very similar to multiple sclerosis. However, due to the rapid progression of MND the prevalence is only about 4–5 per 100 000 compared to about 50 per 100 000 for MS. (MND Association, 2015). People with MND are said to have a series of losses, including the: ■Loss of movement ■Loss of speech ■Loss of ability to eat, drink and breathe. They can have many health and social care professionals involved in their care at any one time. Although often grateful for the support and advice, it can be overwhelming and patients are often confused about roles (Oliver and Webb, 2000). The management of MND is usually provided by a multidisciplinary team based in the hospital and community. There is no cure for MND, with treatment limited to one drug, Riluzole, known to extend survival by only 2–3 months, and has been recommended by the National Institute of Health and Care Excellence (NICE, 2001). The main areas of intervention, are therefore symptom management, and supportive, including interventions to improve quality of life. These may include enteral feeding (Miller et al, 2012; Stavroulakis et al, 2014) and ventilation (Baxter et al, 2013). The physical manifestations of MND/ALS are well known and widely researched. In comparison cognitive impairment in MND is less well recognised.