By Abhijeet Danve, MD, as told by Hallie Levine
I have been studying and treating Ankylosing Spondylitis (AS) for almost 10 years. It is a form of axial spondyloarthritis (axSpA). This is a type of inflammatory arthritis that primarily affects the spine and the sacroiliac (SI) joints, which connect the lower spine to the pelvis. In its early stages, it is referred to as non-radiographic axSpA because its damage is not usually visible on an X-ray. But in its late stages, when it becomes obvious, it is known as ankylosing spondylitis (AS).
Unfortunately, many people with AS go undiagnosed for 8-11 years. Up to 5% of patients with chronic low back pain actually have AS or its earlier form, axSpA. But when you complain to your doctor about back pain, they usually just send you for an X-ray of your lumbar spine or lower back. This won’t help you identify the condition, as the first signs can be seen in your sacroiliac joints. And it can take up to 10 years for these changes to become visible on conventional X-rays. Doctors who treat back pain also lack awareness of this condition. As a result, we sometimes miss this window of opportunity to identify and treat people with AS in earlier stages.
Thankfully, about 10 years ago, new guidelines were released that allow us doctors to diagnose patients earlier. It is now recommended that anyone with suspected axSpA and inconclusive X-rays also have an MRI of their sacroiliac joints. It’s important to ask your doctor for a referral to a rheumatologist if you have chronic back pain that lasts longer than 3 months, begins gradually before age 45, gets worse with rest and gets better with exercise. This is a specialist specially trained to diagnose and treat inflammatory conditions affecting your joints and bones, such as axSpA. They will check you for other symptoms related to this condition, including back pain that wakes you up in the middle of the night, heel or foot pain (plantar fasciitis), or inflammation in other parts of your body like your eyes (called iritis). or uveitis), skin psoriasis and intestinal inflammation (called Crohn’s disease). You can also order a blood test to look for HLA-B27, a gene that increases your chances of getting axSpA. Remember, the sooner you’re diagnosed, the sooner you can begin treatments, which can help improve symptoms, reduce inflammation, and potentially prevent permanent joint damage.
Fortunately, we now have many excellent drugs available to treat both axSpA and AS. Almost half of all people respond well to nonsteroidal anti-inflammatory drugs (NSAIDs) such as naproxen and indomethacin. But if you don’t, there’s a whole class of drugs you can try known as tumor necrosis factor (TNF) blockers. When you have either condition, your body produces too many proteins called cytokines, which increase inflammation throughout the body. Over time, this leads to joint and bone damage. TNF blockers given by injection stop some of these cytokines.
For a long time, these were the only drugs available. But in recent years, the FDA has approved two new injectable drugs: ixekizumab (Taltz) and secukinumab (Cosentyx). Both block a different type of inflammatory cytokine called interleukin-17, or IL-17. Normally, IL-17 helps your body defend itself against infection. But too much of it can cause joint inflammation, bone erosion, and bone fusion. These drugs target different cytokines than TNF inhibitors, so there is hope that they may help those who TNF inhibitors did not help.
Janus kinase (JAK) inhibitors are the newest class of drugs approved by the FDA for the treatment of ankylosing spondylitis. The two JAK inhibitors approved for this use are tofacitinib and upadacitinib. A third is being researched in hopes that it will be available in the future. These are drugs traditionally used to treat rheumatoid arthritis, psoriatic arthritis, and ulcerative colitis. They inhibit several cytokines that are critical to the progression of ankylosing spondylitis. Like biologics, they affect your immune system, but they are also different than biologics. They suppress various targets in your body to prevent overactive immune system responses before they start. JAK inhibitors are more convenient than biologics because you can take them orally.
[TMA2]Studies are ongoing to develop more. There is a new class of oral drugs, Janus kinase (JAK) inhibitors, that show promise. These inhibitors block certain enzymes (JAK1, JAK2, and JAK3) that signal your cells to cause more inflammation. One study found that people who took a JAK inhibitor for just over 3 months were twice as likely to have a severe reaction as those who took a placebo or fake pill. Two drugs, tofacitinib and upadacitinib, are in clinical trials. We should know within the next year if they will be approved by the FDA.
There’s another class of drugs called interleukin-23 inhibitors, like guselkumab and risankizumab, that are just as exciting. These target a cytokine known as interleukin-23 (IL-23), which also signals your cells to make more of another inflammatory cytokine, interleukin-17, or IL-17. When IL-23 is blocked, it stops the production of IL-17. This helps reduce inflammation in your joints and reduce the chance of permanent damage.
As our treatments continue to improve, I tell my patients that they are not enough. Lifestyle is key when it comes to controlling symptoms and improving mobility. Daily movement and stretching exercises are particularly important. These improve flexibility and reduce stiffness, swelling, and pain. You must also exercise regularly, which includes strength and balance exercises.
I also emphasize to my patients that they need to stop smoking. Smoking is bad for everyone’s health, but it’s particularly bad for people with inflammatory diseases like axSpA and AS. Research shows that it can worsen symptoms such as pain and mobility problems. People with axSpA and AS are also more likely to have depression or anxiety. It’s important to seek help, whether through support groups or talk therapy. This can help you cope with living with the disease.