ANKYLOSING SPONDYLITIS

What Is It?
Ankylosing spondylitis (AS) is a type of inflammatory arthritis that primarily affects the spine, although it can also impact other joints. Over time, the inflammation can cause the vertebrae to fuse together, leading to a loss of flexibility, stiffness, and a hunched posture. In severe cases, the bones may become completely fused.

Why It Matters
AS is a chronic, progressive condition that can significantly impact a person’s mobility and quality of life. Because symptoms often start in early adulthood and can be mistaken for general back pain, early diagnosis is key. Starting treatment early can help reduce inflammation, preserve joint function, and prevent complications like spinal deformity.

Key Facts (At a Glance)

  • Prevalence: Affects about 1 in 200 adults in the U.S.

  • Typical Onset: Begins between ages 17–45

  • Gender: More common in men, but can affect women differently (less spinal damage, more peripheral symptoms)

  • Genetic Marker: Strongly linked to the HLA-B27 gene

  • Type: Falls under seronegative spondyloarthropathies

How It Affects the Body
AS causes chronic inflammation in the joints of the spine and sacroiliac joints (where the spine meets the pelvis). Over time, this inflammation leads to new bone growth, which can fuse sections of the spine together. It can also cause pain and stiffness in the hips, shoulders, ribs, and even eyes (due to inflammation called uveitis). The fusion of spinal bones may lead to a forward-stooped posture and reduced lung capacity.

Common Symptoms

  • Chronic lower back pain that improves with activity but worsens with rest

  • Morning stiffness lasting longer than 30 minutes

  • Pain in the hips, shoulders, or buttocks

  • Fatigue

  • Reduced flexibility and mobility

  • Eye pain or redness (uveitis)

  • Difficulty taking deep breaths if ribs are involved

Risks & Side Effects

  • Spinal fusion, leading to limited mobility and stooped posture

  • Reduced lung function

  • Chronic pain and fatigue

  • Inflammation in other parts of the body, including the eyes, heart, and GI tract

  • Fractures of the fused spine after minor trauma

  • Depression or anxiety related to chronic illness

Who Should Be Cautious

  • Individuals with a family history of ankylosing spondylitis or related conditions

  • Those who test positive for the HLA-B27 gene

  • People with inflammatory bowel disease or psoriasis

  • Young men experiencing persistent back pain that improves with movement

  • Patients with recurrent uveitis (eye inflammation)

When to See a Doctor
Seek medical attention if you experience:

  • Back pain that lasts more than 3 months and improves with exercise

  • Persistent morning stiffness

  • Red, painful eyes with blurred vision

  • Difficulty standing up straight or taking deep breaths

  • Fatigue and joint pain that disrupt daily activities
    Early diagnosis by a rheumatologist using imaging (MRI or X-rays) and lab tests can slow progression and prevent joint damage.

Related Conditions / Interactions

  • Other inflammatory diseases such as:

    • Psoriatic arthritis

    • Reactive arthritis

    • Ulcerative colitis/Crohn’s disease (IBD-associated arthritis)

  • Osteoporosis, due to limited movement and chronic inflammation

  • Increased risk of cardiovascular disease in some patients

  • Potential interactions with NSAIDs, biologics, and immune-suppressing drugs

Last Updated: June 15, 2025