Achalasia Causes and Risk Factors

Achalasia is a rare swallowing disorder where the tube connecting your mouth to your stomach (esophagus) cannot properly move food down. This happens because nerves in the esophagus become damaged, and the muscular valve at the bottom (lower esophageal sphincter) fails to relax. The exact cause of this nerve damage is often unknown, but it is not contagious.

What is Achalasia Causes and Risk Factors?

Achalasia is a rare condition affecting your esophagus, the muscular tube that carries food from your throat to your stomach. It occurs when the nerves in your esophagus become damaged, preventing the muscles from pushing food downward. Additionally, the muscular ring at the bottom of your esophagus (lower esophageal sphincter or LES) fails to open properly, making it difficult for food and liquids to enter your stomach.

Normally, your esophagus uses rhythmic muscle contractions (peristalsis) to move food. In achalasia, these contractions weaken or stop entirely. The lower esophageal sphincter (LES) is a valve that usually relaxes when you swallow, allowing food to pass into your stomach. With achalasia, the LES stays tightly closed, creating a blockage. This condition can lead to food and liquid backing up in your esophagus, causing various uncomfortable symptoms. While achalasia can develop at any age, it is most often diagnosed in adults between 30 and 60 years old. It is considered a chronic condition, meaning it is long-lasting, but treatments can help manage symptoms effectively.

Symptoms

The symptoms of achalasia develop slowly over months or even years, often starting subtly and worsening over time. The most common symptom is difficulty swallowing (dysphagia), affecting both solids and liquids. Other key symptoms include regurgitation of undigested food, chest pain, and unintentional weight loss.

Difficulty swallowing (dysphagia) is a hallmark symptom. You might feel like food is stuck in your throat or chest after eating. This can be frustrating and lead to changes in eating habits. Many people with achalasia also experience regurgitation, where undigested food and saliva flow back up into the throat or mouth. This is different from vomiting and can sometimes lead to coughing or choking, especially at night. Some individuals report chest pain or discomfort, which can be mistaken for heartburn, though it often feels more like pressure or squeezing. Because eating becomes difficult and uncomfortable, people with achalasia may eat less, leading to significant and unintentional weight loss. Other possible symptoms include coughing, especially after eating, and sometimes a hoarse voice due to irritation from regurgitated food.

Causes & risk factors

The primary cause of achalasia is damage to the nerves in the esophagus, which control muscle contractions and the relaxation of the lower esophageal sphincter. While the exact reason for this nerve damage is often unknown (idiopathic), it is thought to be an autoimmune response where your body mistakenly attacks its own nerve cells.

In some cases, achalasia may be triggered by a viral infection, such as herpes simplex virus or measles virus, which could initiate the autoimmune process. However, this link is not fully understood and requires more research. Genetic factors are rarely a direct cause, but a small number of cases have been linked to inherited conditions. In certain parts of the world, particularly South America, a parasitic infection called Chagas disease is a known cause of achalasia. This disease, caused by the parasite Trypanosoma cruzi, can damage nerves throughout the body, including those in the esophagus. Risk factors for achalasia are not as clearly defined as for many other conditions. It can affect anyone, but it is most commonly diagnosed in middle-aged and older adults. There is no strong evidence linking achalasia to diet, lifestyle, or specific environmental exposures, beyond the rare cases of Chagas disease.

How it's diagnosed

Diagnosing achalasia typically involves a combination of tests to evaluate the function and structure of your esophagus. These tests include esophageal manometry, which measures muscle contractions and sphincter pressure, and a barium swallow, which uses X-rays to visualize how food moves through your esophagus. An endoscopy may also be performed.

Esophageal manometry is considered the most important test for diagnosing achalasia. A thin, flexible tube is passed through your nose or mouth into your esophagus. Sensors on the tube measure the pressure and coordination of muscle contractions in your esophagus and how well your lower esophageal sphincter (LES) relaxes when you swallow. In achalasia, manometry shows a lack of normal muscle contractions and a failure of the LES to relax. A barium swallow involves drinking a liquid containing barium, which coats the inside of your esophagus. X-ray images are then taken as you swallow. This allows doctors to see the shape of your esophagus, how food moves through it, and if there's any narrowing or a characteristic 'bird's beak' appearance at the LES, which is common in achalasia. An upper endoscopy involves inserting a thin, flexible tube with a camera (endoscope) down your throat to examine the lining of your esophagus, stomach, and the beginning of your small intestine. While endoscopy may not directly diagnose achalasia, it helps rule out other conditions that can cause similar symptoms, such as tumors or strictures, and can assess for any complications like inflammation.

Treatment options

Treatment for achalasia focuses on relaxing or stretching the lower esophageal sphincter (LES) to allow food to pass into the stomach more easily, as the nerve damage itself cannot be reversed. Options range from medications and non-surgical procedures like balloon dilation to surgical interventions, tailored to individual needs and symptom severity.

Medications, such as muscle relaxants (e.g., nitrates or calcium channel blockers), can sometimes be used to relax the LES, but they are generally less effective than other treatments and often have side effects. Another non-surgical option is botulinum toxin (Botox) injection directly into the LES during an endoscopy. Botox temporarily paralyzes the muscles, helping the sphincter relax, but its effects typically last only 6 to 12 months, requiring repeat injections. Pneumatic dilation is a procedure where a special balloon is inserted into the LES and inflated to stretch the muscle fibers. This can provide longer-lasting relief than Botox, but it may need to be repeated. There is a small risk of esophageal perforation with this procedure. Surgical options include a Heller myotomy, where the muscle fibers of the LES are cut to permanently relax the sphincter. This is often performed laparoscopically (minimally invasive). Another newer procedure is peroral endoscopic myotomy (POEM), where an endoscope is used to cut the LES muscle from inside the esophagus, avoiding external incisions. These surgical approaches are generally very effective in providing long-term symptom relief.

Recovery & outlook

Achalasia is a chronic condition, meaning it cannot be cured, but its symptoms can be effectively managed with various treatments. Most people experience significant improvement in swallowing and quality of life after treatment, though some may require repeat procedures or ongoing management. Regular follow-up with your doctor is important.

After treatment, many individuals find that their difficulty swallowing improves considerably, and they can eat a wider range of foods more comfortably. However, it is common to still experience some mild symptoms or require adjustments to eating habits, such as chewing food thoroughly and drinking plenty of water during meals. Long-term management often involves monitoring for potential complications, such as gastroesophageal reflux disease (GERD) or, rarely, an increased risk of esophageal cancer, especially if the esophagus remains significantly dilated. Your doctor will recommend regular check-ups and potentially periodic endoscopies to monitor your condition. The outlook for people with achalasia is generally good with appropriate treatment. While the underlying nerve damage remains, successful treatment of the LES allows for a good quality of life. It is important to discuss any persistent or new symptoms with your healthcare provider to ensure the best possible long-term outcome.

When to see a doctor

You should see a doctor if you experience persistent difficulty swallowing (dysphagia), especially if it affects both solids and liquids. Seek medical attention if you have unexplained weight loss, frequent regurgitation of undigested food, or chest pain that is not relieved by antacids.

Prompt evaluation is important because early diagnosis and treatment can prevent the condition from worsening and reduce the risk of complications. If you notice food getting stuck in your throat or chest regularly, or if you frequently cough or choke after eating, these are strong indicators to consult a healthcare professional. While achalasia symptoms develop slowly, any sudden worsening of swallowing difficulties, severe chest pain, or significant, rapid weight loss warrants immediate medical attention. These could indicate complications or other serious conditions that need urgent assessment. Always discuss your symptoms with a qualified clinician to receive an accurate diagnosis and appropriate treatment plan.

Frequently asked questions

Is achalasia a life-threatening condition?

Achalasia itself is not typically life-threatening, but severe complications can arise if left untreated. These include malnutrition from difficulty eating, aspiration pneumonia from inhaling regurgitated food, and, rarely, an increased risk of esophageal cancer over many years. With proper treatment, these risks are significantly reduced.

Can achalasia be cured?

No, achalasia cannot be cured because the nerve damage in the esophagus is permanent. However, various treatments are highly effective at managing symptoms by relaxing or opening the lower esophageal sphincter, allowing food to pass into the stomach more easily. This significantly improves quality of life.

Is achalasia hereditary or genetic?

Achalasia is rarely hereditary. Most cases are sporadic, meaning they occur without a clear genetic link. A very small number of cases have been associated with specific genetic syndromes, but for the vast majority of people, there is no family history of the condition.

Can diet changes help manage achalasia symptoms?

While diet changes cannot cure achalasia, they can help manage symptoms. Eating smaller, more frequent meals, chewing food thoroughly, drinking plenty of water with meals, and avoiding foods that trigger symptoms (like very cold or very hot items) can make swallowing easier. Elevating your head during sleep can also help reduce nighttime regurgitation.

What is the difference between achalasia and GERD (acid reflux)?

Achalasia involves the lower esophageal sphincter failing to relax, causing food to get stuck in the esophagus. GERD (gastroesophageal reflux disease) is when the LES is too relaxed, allowing stomach acid to flow back up into the esophagus. While both can cause chest pain and regurgitation, their underlying mechanisms and treatments are different.

How common is achalasia?

Achalasia is considered a rare disease. It affects approximately 1 in 100,000 people each year, though prevalence estimates vary. It can occur at any age but is most commonly diagnosed in adults between 30 and 60 years old, with men and women affected equally.

Sources

• MedlinePlus — Achalasia Causes and Risk Factors
• Mayo Clinic — Achalasia Causes and Risk Factors
• Cochrane Library — Achalasia Causes and Risk Factors