ALS, correct terminology Amyotrophic Lateral Sclerosis or Lou Gehrig’s disease, is a debilitating, progressive neurodegenerative disease that often leads to a shortened life expectancy. ALS is part of the group of conditions known as Motor Neurone Diseases. Motor neurones are the cells that control voluntary muscle activity such as speaking, walking, breathing, and swallowing.
The upper motor neurones (UMN) originate in the cortex and brain stem and are responsible for sending signals to the lower motor neurones (LMN) to initiate voluntary movement of the muscles. The damage to the neurones, in ALS, affects both the UMN and LMN, disrupting the signals from the brain to the muscles resulting in weakness, muscle wasting (atrophy) and in some cases stiffness (spasticity) and twitching (fasciculation).
Although not a common disease, it is named after the legendary American baseball player Lou Gehrig, who contracted the disease in 1939 and had to retire from the New York Yankees. The late Stephen Hawking lived with the disease for over 50 years.
Initially the symptoms may not be obvious, and are often dismissed as nothing serious, such as muscle cramps, twitching and stiffness but as the disease progresses, weakness in the upper or lower limbs, difficulty with chewing and swallowing, and slurred speech may become apparent; even simple tasks like doing up buttons, writing and even walking may become difficult. The speed at which the symptoms progress can vary, but eventually muscle weakness will be so pronounced that even getting out of bed will be hard; and once swallowing is affected it can lead to eating less, weight loss and malnourishment. Over time the respiratory muscles will weaken, making breathing difficult.
Despite the loss of physical function, the higher centres in the brain remain intact which means tasks like reasoning, remembering and understanding are not affected. This awareness can often lead to depression as function decreases and dependency on others increases and impending death looms ever closer. In a small percentage of people with ALS, cognitive function may be affected with difficulties in word-finding and decision making, and in some cases a form of dementia.
ALS affects around one in 50,000 people worldwide and is more common in men than women. There are various forms of the disease and symptoms typically begin between 40-60 years of age. However, it may be present at birth and in some cases symptoms can manifest earlier than age 40, even in childhood. ALS can run in families but there are as many cases, if not more, that do not seem to have any connection to genetics or the environment.
Diagnosis can be difficult as there are no tests that can provide a definitive diagnosis of ALS and confirmation is based on a detailed client history, presenting symptoms and the elimination of other conditions with similar symptoms.
There is no cure for ALS and treatment focuses on managing symptoms, improving quality of life and slowing down the progression. Spasticity can make moving around very difficult and may even make the simplest of tasks, like dressing, impossible. To relieve the symptoms of muscle stiffness, medications—known as muscle relaxants—may be prescribed. Strong opioids and anti-inflammatories are also recommended to deal with pain and inflammation. If swallowing or choking are problematic then a diet of liquids may be suggested with feeding through a tube inserted directly to the abdomen to bypass the muscles in the throat.
Another inevitable consequence, as the disease progresses, is difficulty breathing due to the weakening of the respiratory muscles. At this stage the best treatment option is mechanical ventilation to ease discomfort and effort on the respiratory muscles. Respiratory failure is the most common cause of death and usually happens between 3 to 5 years after the first symptoms appear. However, as in the case of Stephen Hawking, some people survive for 10 years or more.
Occupational therapy and physiotherapy are often beneficial and assist to improve posture, prevent joint contractures and slow down muscle weakness and atrophy. Treatment will include advice on safe manual handling and transfer techniques, stretching and strengthening exercises, and respiratory physiotherapy to improve breathing techniques and keep the chest free of secretions. Because of the associated weakness of the muscles around the ribs and diaphragm, coughing can be affected and makes clearing secretions from the chest difficult.
Current research is focusing on drugs to slow down the progression of the disease. Scientists have also had success, in mice, with gene therapy and stem cell for halting and repairing nerves, respectively. However, until a cure is found, the take-home message for people with ALS is to keep as fit and agile as possible, with emphasis on treatments and interventions that make life more comfortable.
