Is ankylosing spondylitis a form of rheumatoid arthritis that primarily causes inflammation

Osteopenia and osteoporosis — both terms for low bone mass, or low bone mineral density — are common complications of ankylosing spondylitis, and both raise the risk of spinal fractures.

While lack of physical activity may contribute to low bone mass later in the disease, a study published in July 2015 in the journal RMD Open concluded that inflammation plays a key role in bone loss in ankylosing spondylitis. (9)

Other potential complications of ankylosing spondylitis include:

Aortitis
Aortic valve disease
Disturbances in the heart’s electrical impulses
Weakened heart muscles
Reduced blood flow to the heart
Fibrosis, or scarring, of the upper lobes of the lungs
Breathing impairment due to chest wall restriction
Sleep apnea
Spontaneous pneumothorax (collapsed lung)
Uveitis

How Ankylosing Spondylitis Causes Aortic Regurgitation

Some people with AS develop chronic inflammation at the base of the heart, around the aortic valve, and at the origin of the aorta, the main artery that carries blood away from the heart.

Years of chronic inflammation can lead to aortic regurgitation, a condition that occurs when the aortic valve doesn't close properly, causing blood to flow backward.

According to the American Heart Association, over time, untreated aortic regurgitation can lead to congestive heart failure, or severe failure of the heart to function properly.

A study published in November 2015 in the American Journal of Medicine reported aortic regurgitation may cause symptoms such as dyspnea— uncomfortable or labored breathing — as well as reduced physical capacity and fatigue that might be wrongly interpreted as symptoms related to a person’s ankylosing spondylitis, not to heart problems. (10)

In this particular study, aortic regurgitation was found in 18 percent of the participants with ankylosing spondylitis. In addition, aortic regurgitation was associated with both age and severity of ankylosing spondylitis.

The researchers suggest that routine care in ankylosing spondylitis include monitoring with both echocardiography and electrocardiography. Once diagnosed, symptomatic aortic regurgitation can be treated with medication or by surgical repair or replacement.

Can Ankylosing Spondylitis Cause Costochondritis?

Costochondritis is a condition that causes pain and tenderness in the chest. The pain happens in an area called the costosternal joints, where the ribs meet the breastbone.

In people with AS, pain in the thoracic spine and around the chest wall is common and is a result of the inflammatory disease. People often have pain in the sternum, costosternal areas, and sternoclavicular joints. Because of the inflammation, there may be inadequate chest expansion. This finding is common enough that it’s included in criteria for ankylosing spondylitis. (11)

Ankylosing Spondylitis Progression

Ankylosing spondylitis is a progressive disease. People with AS may initially have pain in the lower back, sacroiliac joints, or buttocks area that progresses to other areas, including the hips, shoulders, or neck.

For some, if the disease goes untreated, the inflammation may cause the spine to fuse. According to the Mayo Clinic, this fusing makes the spine less flexible, resulting in a hunched-forward posture.

While knowledge is limited on the triggers of AS progression, researchers believe the following predictors are involved: (12)

Exposure to bisphosphonates, a type of osteoporosis treatment, in women
High C-reactive protein levels, an indicator of inflammation, in men
Obesity in men and women
Smoking in men

Overview

Ankylosing spondylitis is an inflammatory disease that, over time, can cause some of the bones in the spine (vertebrae) to fuse. This fusing makes the spine less flexible and can result in a hunched posture. If ribs are affected, it can be difficult to breathe deeply.

Ankylosing spondylitis affects men more often than women. Signs and symptoms typically begin in early adulthood. Inflammation can also occur in other parts of the body — most commonly, the eyes.

There is no cure for ankylosing spondylitis, but treatments can lessen symptoms and possibly slow progression of the disease.

Symptoms

Early signs and symptoms of ankylosing spondylitis might include pain and stiffness in the lower back and hips, especially in the morning and after periods of inactivity. Neck pain and fatigue also are common. Over time, symptoms might worsen, improve or stop at irregular intervals.

The areas most commonly affected are:

The joint between the base of the spine and the pelvis
The vertebrae in the lower back
The places where tendons and ligaments attach to bones, mainly in the spine, but sometimes along the back of the heel
The cartilage between the breastbone and the ribs
The hip and shoulder joints

When to see a doctor

Seek medical attention if you have low back or buttock pain that came on slowly, is worse in the morning or awakens you from your sleep in the second half of the night — particularly if this pain improves with exercise and worsens with rest. See an eye specialist immediately if you develop a painful red eye, severe light sensitivity or blurred vision.

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Causes

Ankylosing spondylitis has no known specific cause, though genetic factors seem to be involved. In particular, people who have a gene called HLA-B27 are at a greatly increased risk of developing ankylosing spondylitis. However, only some people with the gene develop the condition.

Risk factors

Men are more likely to develop ankylosing spondylitis than are women. Onset generally occurs in late adolescence or early adulthood. Most people who have ankylosing spondylitis have the HLA-B27 gene. But many people who have this gene never develop ankylosing spondylitis.

Complications

In severe ankylosing spondylitis, new bone forms as part of the body's attempt to heal. This new bone gradually bridges the gap between vertebrae and eventually fuses sections of vertebrae. Those parts of the spine become stiff and inflexible. Fusion can also stiffen the rib cage, restricting lung capacity and function.

Other complications might include:

Eye inflammation (uveitis). One of the most common complications of ankylosing spondylitis, uveitis can cause rapid-onset eye pain, sensitivity to light and blurred vision. See your doctor right away if you develop these symptoms.
Compression fractures. Some people's bones weaken during the early stages of ankylosing spondylitis. Weakened vertebrae can crumple, increasing the severity of a stooped posture. Vertebral fractures can put pressure on and possibly injure the spinal cord and the nerves that pass through the spine.
Heart problems. Ankylosing spondylitis can cause problems with the aorta, the largest artery in the body. The inflamed aorta can enlarge to the point that it distorts the shape of the aortic valve in the heart, which impairs its function. The inflammation associated with ankylosing spondylitis increases the risk of heart disease in general.

Nov. 25, 2021

Is ankylosing spondylitis a form of rheumatoid arthritis?

Affected joints can feel swollen and tender. How is it different? Ankylosing spondylitis usually produces symptoms in the low back, hips, and/or shoulders first. In contrast, rheumatoid arthritis usually first affects smaller joints, such as those in the hands and feet (occasionally the knees are the first affected).

Is ankylosing spondylitis a form of rheumatoid arthritis that primarily causes inflammation of the joints between the vertebrae?

Ankylosing spondylitis (pronounced ank-kih-low-sing spon-dill-eye-tiss), or AS, is a form of arthritis that primarily affects the spine, although other joints can become involved. It causes inflammation of the spinal joints (vertebrae) that can lead to severe, chronic pain and discomfort.

Is ankylosing spondylitis a type of inflammatory arthritis?

Ankylosing spondylitis (AS) is a chronic inflammatory disease causing axial arthritis, frequently resulting in inflammatory low back pain early in the disease course, with eventual severe impairment of spinal mobility due to structural changes ultimately leading to spinal fusion.

Can you have ankylosing spondylitis and rheumatoid arthritis at the same time?

Today there are no major diagnostic difficulties in differentiation between these diseases, thanks to modern laboratory tests and imaging. However, a problem may arise when the patient has symptoms typical for both diseases simultaneously. Cases of coexistence of RA with AS – according to our best knowledge – are rare.