Cognition in ALS and people with amyotrophic lateral sclerosis

Stem cells and ALS

Cognition in ALS – amyotrophic lateral sclerosis – has received some attention and debate. A longitudinal study in a large cohort of people with amyotrophic lateral sclerosis in Piemonte and Valle d’Aosta in Italy found that cognitive and motor deficits evolve in parallel with the course of the disease, according to the natural history of each patient.

Adriano Chiò et al Neuroloy 2019,93:e984-e994

The study included 797 cases between 2007 and 2015. It was an ideal study, population based, using a validated neuropsychological battery, with genetic testing in 749 cases (94% of the total). Patients exhibited greater cognitive imparment when the disease was more advanced and the motor deficit more pronounced. Frontotemporal dementia was more frequent and pronounced in patients with a bulbar onset and bulbar involvement at the time of testing. Results were the same independent of the presence of CL90RFT2 genetic expansion. This is the largest study of its kind, touching on the subject of cognition in ALS, supported by public government funds. The results are very likely generalizable to patients in other settings.

These findings, of course, need to be considered in the light of many neurologist’s experience with terminal patients with amyotrophic lateral sclerosis who, in spite of their locked-in status, preferred to go on living with invasive respiratory and nutritional support. A study has shown that these patients demonstrate surprisingly low levels of depressed mood, reasonable quality of life, and commitment to living. Eye-tracking software has been used to interview these patients, who, as a whole, remain satisfied with their decision to use invasive support. This was a small study in 25 patients in Poland. The obvious limitations to the results arise from the fact that it is only natural that people would be satisfied with what they chose to do, and would not be available for interview unless so satisfied. Still, it shows that there is a group of people with amyotrophic lateral sclerosis who adjust well to this new “normal”, and show resilience and cognitive refraiming in view of the steps of progression of the disease.

Kuzma-Kozakiewicz et al. Neurology 2019, 93:e938-e945

SM Albert and P Wicks. Neurology 2019, 93: 419-420

The standards of use of invasive ventilation and nutrition go from 33% of people with amyotrophic sclerosis in Japan to 20% in South Korea, 16% in Italy and only 8% in the USA. Only 10 years ago, during specialized neurology courses of the American Academy of Neurology, when discussing cognition in amyotrophic lateral sclerosis, experts stated that it was unethical to use these invasive methods in these people. The idea seemed to be that it was unethical to make money on these people who were really in death row. This was obviously a prejudiced medical posture, not at all human, contrary to post-war human rights, which state that all people have a right to decide their fate, and not their physicians, specially when they are in a position in which they cannot even voice, much less fight for, their opinion about their own destiny. In summary, patients almost in a locked in state are not in an usual ethical situation to give their informed consent to their own death. But, certainly, this does not mean that their consent is not relevant.

Dr Paulo Bittencourt