Amyotrophic lateral sclerosis (ALS), which is also known as Lou Gehrig’s disease, is a progressive and degenerative disease that affects the nervous system. It attacks those cells within the spinal cord and brain that control the movement of muscles. It does not, however, affect any of the senses like sight or hearing. Nor does ALS usually affect the bladder or the bowel.
There is currently no cure for ALS, and most patients survive for two to five years after the first appearance of their symptoms. About ten percent survive for ten years or longer. The physicist Stephen Hawking, 76, has survived for over 50 years. He has a very rare early-onset form that progresses extremely slowly. A patient’s life expectancy depends on if and when their swallowing muscles and/or diaphragm are affected. If they’re not, the patient can survive for years or even decades.
1. Muscle Weakness
There are at least two forms of ALS: limb-onset ALS and bulbar-onset ALS. Both are categorized by their earliest symptoms. In bulbar-onset ALS, which affects 25 percent of patients, speech problems are the earliest symptoms. In limb-onset ALS, the most common type, the patient develops twitching and cramps in at least one limb. They will also experience balance problems and weakness in their hands and feet.
In many cases, the first symptoms affect a hand and arm. The patient notices that they are starting to have trouble with simple tasks like turning a key in a lock, buttoning a shirt, or writing a letter. If the ALS attacks a leg first, the patient may find they are tripping or stumbling more often. Walking and running become increasingly difficult.
As the disease progresses, the muscle weakness spreads to other parts of the body. As their limbs all weaken, the patient loses the ability to stand or walk, use their hands, and get out of bed unassisted. The patient’s muscles also atrophy or become smaller. In late-stage ALS, the muscles in the respiratory system weaken, and the patient has trouble breathing. Many depend on a ventilator for they can no longer breathe on their own. Late-stage patients also become increasingly vulnerable to respiratory diseases like pneumonia.
2. Stiff Muscles
ALS affects the upper motor neurons in the brain and the lower motor neurons in the brainstem and spinal cord. When ALS attacks the lower motor neurons, it causes twitching and muscle weakness. When it affects the upper motor neurons, the patient develops spasticity or stiff muscles. Both symptoms can affect the patient at the same time. In spasticity, the affected muscles are trying to extend and flex at the same time. They can become so tight that they cause the patient pain. Spasticity is sometimes confused with cramps, another painful symptom ALS patients develop. Spasticity, however, affects a larger area than do cramps.
3. Vocal chord spasm
A laryngospasm or vocal chord spasm is a type of choking in which water or saliva gets into the larynx and cause the vocal folds to have a spasm that shuts off the airway. Unlike other types of choking, laryngospasms occur when the patient isn’t eating. In fact, they can sometimes happen when the patient is sleeping. Vocal chord spasms, while terrifying, aren’t fatal. The vocal chords relax after a minute or two, and the patient can breathe again.
4. Impaired voice
In many cases, the patient’s voice will change and become hoarse, nasal or raspy. Their voice can also become softer or fainter. As this change can indicate breathing problems, the patient should be checked for such. As with other speech problems, like those described below, changes in the voice are caused by damage to the neurons in the brainstem, which is sometimes called the bulb because of its resemblance to a plant bulb. That damage, in turn, affects the muscles that move the vocal cords, soft palate, lips, jaw, and tongue. The muscles tighten and become weaker and thus affect the patient’s voice and speech.
5. Fatigue
As the patient’s muscles weaken, they will have less and less energy. Fatigue will affect even the undamaged muscles, for the patient will need to compensate for the weakened muscles. For example, a patient with a weakened leg will put more weight on the other leg and thus exhaust both limbs. Some patients will sleep a lot more than usual – up to 12 hours a day. As the disease worsens, even an activity like being bathed by a caregiver will leave the patient tired. Extreme fatigue in a patient with late-stage ALS indicates they may have developed breathing problems and need a ventilator.
6. Drooling
Drooling is one of the more annoying and embarrassing symptoms of ALS. It’s not caused by the patient producing an abnormally high amount of saliva but by their growing inability to swallow it. As ALS progresses, the patient’s throat muscles weaken, so swallowing becomes increasingly difficult. In addition to embarrassment, drooling can also cause choking, trouble speaking, and skin irritation. It is also a surprisingly tricky symptom to treat, for medications that reduce drooling can often cause other problems like dry mouth or abnormally thick saliva. Both drooling and the medications for reducing it can increase the patient’s need for water.
7. Severe unintentional weight loss
Patients with ALS generally burn calories at a faster pace than do healthy people. Between that and their difficulties swallowing as described below, they can lose a lot of weight and become malnourished. Other problems that impair an ALS patient’s ability to eat include constipation, inability to use their arms and/or hands, loss of appetite, nausea, and trouble breathing. The last means the patient has to expend more energy simply to breathe, which means they need to eat more to fuel their body. In many patients, in fact, difficulty eating and difficulty breathing occur together. An ALS patient will often find eating to be a long and tiring process.
8. Difficulty swallowing
As ALS worsens, the muscle weakness affecting the limbs spreads to other parts of the body, including the swallowing muscles. Swallowing actually has three stages: oral, which includes chewing, reflex, and esophageal. During the reflex stage, the soft palate, epiglottis and vocal cords work together to keep the food from going down the “wrong pipe.” As ALS progresses, the cranial nerves controlling these anatomical features are damaged so they can no longer control the reflexes. Food and drink start going down the wrong pipe and end up in the patient’s trachea or lungs and cause choking or a respiratory infection. Coughing when swallowing is an early sign of developing problems.
9. Difficulty Speaking
In about a quarter of cases, trouble speaking is the first symptom of ALS. The patient begins slurring their words. Difficulty speaking, more formally called dysarthria, can take other forms, and it can occur at any time. It often accompanies or follows trouble swallowing, however. The increased effort used to speak will tire the patient, especially if they also have trouble breathing. Speech problems are upsetting and frustrating for the patient, especially if their disease has progressed to the point where they have limited mobility. In such patients, communicating and expressing themselves are among the few things they can still do independently.
10. Overactive reflexes
Overactive reflexes, more formally known as hyperreflexia, indicate damage to the upper motor neurons. The hyperactive reflexes will cause uncontrollable twitching or spastic movements. Even mild stimuli can cause a bout of hyperreflexia. In some cases, patients will develop a hyperactive gag reflex that makes it hard for them to swallow their food and cause them to throw up a lot of it. A hyperactive gag reflex is caused by damage to the pharyngeal nerves. Babinski’s sign, another indicator of damage to the upper motor neurons, is an abnormal reflex in which the big toe flexes upward when the sole is stimulated. It occurs in about 50 percent of patients.
