What ALS is and how it affects the body
ALS, or amyotrophic lateral sclerosis, is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord. It belongs to a wider group of conditions known as motor neuron diseases. In ALS, both upper and lower motor neurons degenerate, leading to gradual loss of muscle control. Early signs often include tripping, dropping objects, slurred speech, or trouble swallowing. The disease typically does not significantly affect cognition, sight, hearing, or bowel and bladder function. Over time, weakness progresses, and breathing muscles may be involved, which is why respiratory support and comprehensive care are central to long-term management.
Historical recognition and naming of ALS
The disease was first described in the late 19th century, with detailed clinical reports emerging in the 1860s and 1870s. The name amyotrophic lateral sclerosis reflects its features: "a-" meaning no, "myo-" referring to muscle, and "trophic" meaning nourishment, because the motor neurons no longer send messages to muscles. Lateral sclerosis refers to scarring within the spine's lateral columns. ALS became widely known in the 20th century as clinicians in Europe and North America reported similar patterns of paralysis. The convergence of clinical signs, electromyography findings, and postmortem nerve cell loss established ALS as a distinct disorder with a recognizable progression and predictable patterns of involvement.
Key early descriptions and clinicians
Jean-Martin Charcot in Paris provided a landmark clinical account in the 1860s, linking muscle weakness, atrophy, and abnormal reflexes to degeneration in the spinal cord and brain. In the United Kingdom, Sir William Gowers detailed patterns of weakness and brisk reflexes consistent with upper and lower motor neuron involvement. In the United States, reports by physicians such as Joseph Collins and others described similar relentless loss of strength without objective sensory changes. These early accounts created a shared vocabulary and diagnostic criteria, enabling consistent identification of ALS across centers and forming the foundation for modern classification.
Notable people who had ALS
ALS can affect anyone, but some individuals have brought high visibility to the condition through their achievements and public experience. These include scientists, athletes, artists, and military leaders, whose stories have helped shape public understanding while underscoring the broad impact of the disease.
| Name | Known for | ALS diagnosis or status | Source type |
|---|---|---|---|
| Stephen Hawking | Theoretical physicist and author | Diagnosed at age 21, lived with ALS for over 50 years | Verified biography and public statements |
| Lou Gehrig | Professional baseball player | Diagnosed in 1939, disease named eponymously as "Lou Gehrig's disease" | Medical records and historical sports reports |
| Doddie Weir | Rugby player and charity advocate | Diagnosed in 2016, public awareness campaigns | Medical disclosure and interviews |
| Rita Mae Brown | Author and activist | Disclosed ALS diagnosis in 2020 | Public statement and media coverage |
| Sam Schmidt | Former racing driver and advocate | Diagnosed in 1995, continued motorsport advocacy | Medical disclosure and advocacy profile |
| Euan MacDonald | Technology entrepreneurFounded Euan’s Guide after diagnosis | Verified biography and organization records |
Signs, symptoms, and how ALS progresses
ALS usually begins with focal weakness, often in the hands, feet, or speech muscles. People may notice tripping, difficulty buttoning shirts, or changes in handwriting size. Cranial nerve involvement can cause slurred speech or swallowing difficulty, a pattern historically described as bulbar onset. Limb onset is more common, with asymmetrical weakness in an arm or leg. As the disease advances, weakness spreads to other regions, and muscles may twitch visibly (fasciculations). Despite these changes, sensation, thinking, and senses typically remain intact. Eventually, respiratory muscles weaken, leading to shortness of breath and reduced tolerance for lying flat, often necessitating noninvasive ventilation or other respiratory interventions.
Diagnosis and ruling out other conditions
There is no single test for ALS; diagnosis relies on clinical evaluation, electromyography, nerve conduction studies, and neuroimaging. Criteria such as the El Escorial or Airlie House definitions guide clinicians by specifying patterns of weakness, absent sensory signs, and evidence of upper and lower motor neuron involvement in at least three regions. Neuroimaging helps exclude structural causes like cervical myelopathy or brainstem lesions. Blood and cerebrospinal fluid tests support exclusion of mimics such as autoimmune neuropathies, thyroid disease, or heavy metal toxicity. Because progression is typically relentless, longitudinal follow-up is often necessary to confirm the clinical pattern and refine the diagnosis.
Treatment, care, and management options
While there is no cure for ALS, several interventions can help manage symptoms and may modestly affect survival. Riluzole and edaravone are approved medications that have shown small but meaningful effects on prolonging survival or slowing functional decline in some people. Noninvasive ventilation improves outcomes for respiratory support, and timely use is associated with better quality of life. Nutritional support, including dietary modification or feeding assistance, can help maintain weight and reduce aspiration risk. Multidisciplinary clinics that include neurologists, physiotherapists, speech-language pathologists, respiratory therapists, and palliative care specialists have been associated with improved coordination of care and symptom control. Assistive technology, ranging from communication devices to mobility aids, can sustain independence and participation for longer periods.
Causes and current understanding of risk
Most cases of ALS are sporadic, with no clear family history, although research is actively exploring genetic, environmental, and aging-related factors. In a smaller subset, familial ALS is linked to specific gene variants, such as mutations in C9orf72, SOD1, and TARDBP. These discoveries have improved biological understanding and opened avenues for targeted therapies and clinical trials. Despite extensive investigation, firm preventable causes remain elusive, and no strategy has yet been proven to reliably prevent ALS. Age remains the strongest epidemiological risk factor, with most people diagnosed between 55 and 75, and a slight male predominance in earlier-onset forms. Ongoing studies aim to clarify interactions between genes, lifestyle, and occupational factors, but current evidence supports a multifactorial model rather than a single definitive cause.
Living with ALS and support resources
People with ALS can experience a wide range of functional changes, and pacing activity and energy conservation become important strategies. Adaptive equipment, home modifications, and communication planning can sustain safety and autonomy. Emotional and practical support from family, friends, and formal services is crucial, as is early involvement of palliative care focused on symptom relief and values-based care planning. Advocacy organizations provide education, peer support, and information on clinical trials. While the course of ALS is variable, many people find meaningful ways to maintain quality of life, engage in preferred activities, and contribute to their communities with appropriate supports in place.