Ankylosing spondylitis is a long-term inflammatory condition that primarily targets the spine and can gradually change how your body moves and feels. Understanding what lies ahead and how this disease may progress helps patients and their families prepare for the journey and make informed decisions about care and daily life.

Understanding What to Expect: Prognosis

If you or a loved one has been diagnosed with ankylosing spondylitis, it’s natural to wonder what the future holds. The outlook for people with this condition varies greatly from person to person, and predicting exactly how the disease will progress is challenging. What doctors do know is that for many individuals, ankylosing spondylitis follows a pattern of flare-ups and periods of relative calm, where symptoms may improve or even disappear for a while before returning.^[1]

Some people with ankylosing spondylitis remain fully independent or experience only minimal disability throughout their lives. They are able to work, maintain relationships, and participate in activities they enjoy with appropriate treatment and lifestyle adjustments. For others, the condition progresses more significantly over time, leading to greater physical limitations.^[5]

The good news is that with modern treatments, ankylosing spondylitis does not typically affect life expectancy in a major way. Most people with the condition can expect to live a normal lifespan. However, the disease does carry an increased risk of certain complications that need monitoring and management by healthcare professionals.^[5]

Age plays a role in how the disease manifests. Approximately 80% of people with ankylosing spondylitis experience their first symptoms before the age of 30, and the condition commonly presents in individuals younger than 40.^[4] Starting treatment early, before permanent damage occurs, offers the best chance of maintaining flexibility and quality of life.^[8]

One important factor that influences prognosis is how quickly the condition is diagnosed. Unfortunately, diagnosis is often delayed by five to six years because symptoms develop gradually and can be mistaken for other, less serious back problems.^[4] This delay can allow inflammation to cause damage that might have been prevented or reduced with earlier intervention.

How the Disease Develops Without Treatment

When ankylosing spondylitis is left untreated, the ongoing inflammation in the spine and joints can lead to significant changes in the body’s structure. The hallmark of this disease is inflammation in the sacroiliac joints, which are located where the base of the spine meets the pelvis. This inflammation, called sacroiliitis, causes the characteristic lower back and buttock pain that many people with the condition experience.^[2]

Over time, the body responds to this chronic inflammation by forming new bone in an attempt to heal the affected areas. This new bone gradually bridges the gaps between the small bones in the spine, called vertebrae. As more and more vertebrae become connected by this extra bone growth, sections of the spine begin to fuse together.^[1]

This fusion makes the spine less flexible and can significantly limit movement. In advanced cases, the spine can become completely rigid, a condition sometimes called a “bamboo spine” because of how it appears on X-rays. The fused vertebrae look like segments of bamboo stacked on top of each other.^[6]

The natural progression tends to start at the sacroiliac joints and work its way up the spine, though recent research suggests the pattern may be less predictable than previously thought, with fusion sometimes occurring in a jumping pattern rather than steadily ascending from bottom to top.^[6]

As the spine stiffens and loses its natural curves, posture changes become noticeable. Many people develop a forward-hunched position. If the joints in the chest are affected by the fusion process, the rib cage becomes less able to expand, which can make taking deep breaths difficult and lead to reduced lung capacity.^[1]

Without treatment, the pain and stiffness tend to be worse in the early morning hours, often disturbing sleep. Many patients report that symptoms improve somewhat with physical activity and worsen with prolonged rest or inactivity.^[6] This distinctive pattern—feeling worse after rest and better with movement—is one of the key features that helps doctors distinguish ankylosing spondylitis from other types of back pain.

Possible Complications and Unexpected Developments

Ankylosing spondylitis can affect more than just the spine, and several complications may develop that require additional attention and care. Understanding these possibilities helps patients know what symptoms to watch for and when to seek medical help.

One of the most common complications involves the eyes. Between 25% and 35% of people with ankylosing spondylitis develop a condition called acute anterior uveitis, also known as iritis. This is an inflammation of the middle layer of the eye that causes redness, pain, light sensitivity, and blurred vision. It typically affects one eye at a time and requires prompt treatment with eye drops to prevent vision damage.^[4]

The bones themselves become more fragile in people with ankylosing spondylitis. Osteoporosis, or weakening of the bones, develops more frequently in this population, making fractures more likely. People with ankylosing spondylitis face at least twice the risk of vertebral fragility fractures—broken bones in the spine—compared to people without the condition. Because the spine may be rigid and unable to bend, even minor falls or impacts can cause serious fractures.^[4][3]

The heart and blood vessels can also be affected by the chronic inflammation associated with ankylosing spondylitis. Some people develop aortitis, which is inflammation of the aorta, the body’s largest blood vessel. Others may experience irregular heart rhythms (called arrhythmia) or cardiomyopathy, a disease of the heart muscle. The overall risk of cardiovascular disease is increased in people with ankylosing spondylitis, believed to be caused by the ongoing inflammation throughout the body.^[4][3]

Lung problems can occur when the rib cage becomes stiff and chest expansion is limited. This creates a restrictive pattern of breathing that can predispose individuals to respiratory issues. Additionally, the reduced ability to take deep breaths can make it harder to clear the lungs effectively.^[4]

Gastrointestinal issues are surprisingly common. Inflammatory bowel disease, which includes conditions like Crohn’s disease and ulcerative colitis, affects up to 50% of people with ankylosing spondylitis at some point. These conditions cause abdominal pain, diarrhea, and other digestive symptoms that require separate treatment.^[4]

About 10% of people with ankylosing spondylitis also have psoriasis, a skin condition that causes raised, red, scaly patches on the skin. This overlap between conditions is part of a broader family of related diseases called spondyloarthritis.^[4]

In rare cases, people with advanced ankylosing spondylitis may develop nerve-related complications. These can include spinal cord injury from fractures, atlantoaxial subluxation (where the top of the spine becomes unstable), or even cauda equina syndrome, a serious condition where nerves at the bottom of the spinal cord become compressed, causing leg weakness, numbness, and loss of bladder or bowel control.^[4]

Impact on Daily Life and Activities

Living with ankylosing spondylitis means adapting to changes in how your body moves and feels. The disease affects many aspects of daily life, from the simplest morning routines to major life decisions about work and family.

One of the most challenging aspects is dealing with chronic pain and stiffness, particularly in the lower back and hips. This pain is often worst in the early morning or after periods of sitting or lying down, which can make getting out of bed a difficult and painful process. Many people find they need extra time in the morning to loosen up before they can start their day.^[7]

Fatigue is another significant challenge that doesn’t always get the attention it deserves. The ongoing inflammation in the body uses up energy, leaving many people feeling exhausted even when they haven’t been physically active. This tiredness can affect concentration, mood, and the ability to keep up with work or family responsibilities.^[7]

Physical activities and hobbies may need to be modified or approached differently. While staying active is crucial for managing ankylosing spondylitis, certain high-impact activities or contact sports may become risky, especially if the spine has already begun to stiffen or fuse. Working with a physical therapist can help identify safe ways to exercise and maintain fitness without increasing the risk of injury.^[17]

Work life often requires adjustments. People whose jobs involve heavy lifting, prolonged sitting, or repetitive bending may find these tasks increasingly difficult. Some may need to request workplace accommodations, such as a more supportive chair, a standing desk, or the ability to take frequent breaks to move and stretch.^[17]

Sleep quality frequently suffers, not just because of pain but also because finding a comfortable sleeping position becomes harder as the spine stiffens. Poor sleep then contributes to increased pain sensitivity and worsens fatigue, creating a challenging cycle. Using a firm mattress, avoiding pillows that are too thick, and sleeping on the back rather than the stomach can help.^[17]

Simple household tasks like cleaning, cooking, gardening, and doing laundry may become more tiring or painful. Using long-handled tools to reduce bending and reaching, sitting down to do tasks when possible, and asking for help when needed are practical strategies that can make home life more manageable.^[17]

Social relationships and emotional well-being are also affected. The invisible nature of pain means others may not understand why someone with ankylosing spondylitis needs to decline invitations, take breaks, or avoid certain activities. This can lead to feelings of isolation or frustration. Some people also struggle with changes in their appearance, particularly if they develop a stooped posture.^[16]

On the positive side, many people with ankylosing spondylitis find that a combination of medication, regular exercise, and lifestyle adjustments allows them to maintain a good quality of life. Learning to pace activities, taking time for self-care, and staying connected with healthcare providers and support networks makes a meaningful difference in how well people manage day to day.^[16]

Supporting Family Members Through Clinical Trials

When a family member has ankylosing spondylitis, everyone in the family is affected in some way. Understanding the condition, including how it’s being studied and what treatment options are being developed, can help family members provide better support and advocacy.

Clinical trials are research studies that test new treatments, medications, or approaches to managing ankylosing spondylitis. While not every patient will participate in a clinical trial, knowing about them is important because they offer potential access to cutting-edge treatments before they become widely available. They also contribute to the broader understanding of the disease, which helps future patients.

If your family member is considering participating in a clinical trial, there are several ways you can help. First, assist with researching available trials. Look for studies that are recruiting participants with ankylosing spondylitis in your area. Many hospitals, research centers, and patient advocacy organizations maintain databases of ongoing trials. The National Library of Medicine’s ClinicalTrials.gov website is a reliable resource for finding legitimate studies.

Help your loved one evaluate whether a particular trial might be a good fit. This involves reading through the eligibility criteria, understanding what the trial involves (such as how many visits are required, what tests or procedures will be done, and how long the study lasts), and discussing potential benefits and risks with their rheumatologist.

Offer practical support if they decide to participate. Clinical trials often require more frequent doctor visits and more extensive monitoring than regular care. You might help by providing transportation to appointments, keeping track of the study schedule, helping to report side effects or symptoms accurately, and taking notes during meetings with research staff.

Emotional support is equally important. Participating in a clinical trial can bring up complex feelings—hope that the new treatment will help, anxiety about potential side effects, and frustration if the treatment turns out not to be effective or if they’re assigned to a control group. Being available to listen and validate these feelings makes the experience less isolating.

It’s also helpful to understand that participation in a clinical trial is entirely voluntary and that your family member can withdraw at any time without affecting their regular medical care. Sometimes family members worry about appearing unsupportive if they express concerns about a trial, but open communication about worries and questions is actually very supportive.

Learn about the disease alongside your family member. Understanding why inflammation happens, how treatments work, and what symptoms to watch for helps you recognize when things are improving or when problems might be developing. This knowledge also helps you advocate effectively when dealing with insurance companies, employers, or healthcare providers.

Encourage participation in support groups, either in-person or online. Many patient advocacy organizations offer resources specifically for families, including educational materials, forums where family members can connect with each other, and tips for caregiving. These connections remind everyone that they’re not alone in facing the challenges of ankylosing spondylitis.

Finally, take care of your own well-being. Supporting someone with a chronic condition can be demanding, both physically and emotionally. Make sure you’re getting enough rest, maintaining your own social connections, and seeking support when you need it. You’ll be better able to help your loved one when you’re taking care of yourself too.