Facts & figures

Diagnosis facts

More women than men are being diagnosed with non-radiographic axial spondyloarthritis.

On average, 80% of HLA-B27 positive children born to a parent suffering with AS who is also HLA-B27 positive are likely to remain unaffected by AS.

About 85% to 90% of people with ankylosing spondylitis have the HLA-B27 gene. Of those people who carry the HLA-B27 gene, however, only about 5% will develop spondyloarthritis.

The HLA-B27 gene is closely associated with spondyloarthritis. The gene occurs at different rates in different populations, ranging from 0% for Bantu populations in southern Africa, to 8% in white Europeans, to 20-50% for the Haida people of British Columbia.

Ankylosing spondylitis is a young person’s disease. It most frequently starts between ages 15 and 35. Onset after age 45 is unusual.

Drug facts

There are many genes that are now associated with spondyloarthritis. New biologic drugs are being made that work on these genes. For example, an IL-17 inhibitor is approved for use in patients with AS and PsA.

Biosimilars are usually cheaper than the biologic drug to which they are similar by about 30% to 40%.

Biosimilars, which used to be known in Canada as Subsequent Entry Biologics, are drugs that are similar to an original biologic drug. They are usually manufactured by a competitor once the patent on the original biologic drug expires.

Tumor Necrosis Factor Inhibitors (TNFi or anti-TNF) drugs are known as biologic drugs. They are made from large live molecules.

Lifestyle facts

Obese and overweight patients have a lower response rate to TNF Inhibitors. For those patients, losing weight may improve the response rate.

Don’t smoke if you have AS! Your disease will progress faster and, if you are taking a TNF Inhibitor, your response to it may be impaired. Smoking results in poorer disease outcomes.

“Walking is man’s best medicine” — Hippocrates (c. 460 BC – c. 370 BC)

Exercise is a recommended treatment option to help manage spondyloarthritis.

ASAS, the Assessment of SpondyloArthritis international Society, recommends membership in a patient organization as an additional treatment option.

Types of arthritis

Non-Radiographic axial spondyloarthritis or nrAxSpA describes the early symptoms of ankylosing spondylitis detected by MRI and other tests where a confirmation of ankylosing spondylitis cannot be confirmed by X-ray. Not all cases of nrAxSpA turn out to be ankylosing spondylitis.

Axial spondyloarthritis is a term to describe the possible early stage of ankylosing spondylitis, before it can be detected by X-ray.

Osteoarthritis is associated with aging whereas inflammatory arthritis can start in children and frequently occurs in young adults.

Seronegative arthritis is male predominant by about 3:1 in ankylosing spondylitis. In the case of psoriatic arthritis (PsA), however, the male to female ratio is 1:1.

Spondyloarthritis is seronegative. That is, a blood test will not show the presence of rheumatoid factor (RF) that is produced as the immune system attacks healthy tissue.

Rheumatoid arthritis is seropositive. That is, a blood test shows the presence of RF or rheumatoid factor. RF is produced as the immune system attacks healthy tissue.

Nearly everyone has heard of rheumatoid arthritis, a common form of inflammatory arthritis, but hardly anyone has heard of spondyloarthritis, another form that is almost as common.

Inflammatory arthritis covers a number of autoimmune diseases in which the body’s own immune system attacks the joints.

Osteoarthritis is caused by the deterioration of cartilage in the joints, often due to wear and tear.

Arthritis can be divided into two sub-groups: inflammatory arthritis and osteoarthritis, which is far more common.

There are over 100 types of arthritis.