What causes the death of people with ALS who are already receiving tube feeding and mechanical ventilation?

Feeding via a PEG tube and invasive ventilation can extend life by many years. Despite the life-prolonging effects of nutritional and respiratory therapy, life expectancy may still be limited.

Two causes of death must be taken into account here. The first cause of death is a decline in the will to live. Experience has shown that, in cases of long-term mechanical ventilation, the ability to communicate is of decisive importance for the will to live. The limitation of eye movement and the resulting reduction in the ability to communicate are common reasons for discontinuing life-prolonging measures.

Another cause of death is the spread of ALS to the autonomic nervous system, which is responsible for regulating heart activity. In this scenario, life expectancy may be limited by the onset of cardiac arrhythmias.