For those who believe one disease is never enough, welcome to the world of psoriatic arthritis (PsA), a challenging combo of the skin disease psoriasis and the inflammatory autoimmune disease, arthritis. Along with the itchy and uncomfortable red skin patches covered with silvery scales, a hallmark of psoriasis, those with PsA also contend with the joint pain that is a signature of arthritis. “Psoriatic arthritis affects approximately 25% of people with psoriasis,” says Eric Ruderman, M.D., a rheumatologist at Northwestern Medicine in Chicago. “It’s a form of inflammatory arthritis that causes swelling and pain in the joints or the tendons.”
While psoriatic arthritis generally develops several years after the skin disease, it’s possible (though rare) to have symptoms of joint pain before psoriasis’ telltale red patches appear. The two conditions coincide but do not directly influence each other. “Patients with extensive psoriasis may be more likely to develop psoriatic arthritis, but there isn’t generally a relationship between the severity of the arthritis and the severity of the skin disease,” says Dr. Ruderman.
Along with joint pain, bone health is a major concern if you have PsA. That’s because over time, as inflammation damages the cartilage at the ends of your bones, the bones themselves can begin to rub against each other, eroding and weakening them. The inflammatory process also damages the ligaments and tendons supporting the bone structure, leading to destabilization in your joints.
While there is no known cure for PsA, there are steps you can take to keep your bones as strong as possible, allowing you to live a full and active life. Here’s what you need to know about how this disease affects your bone health, and what you can do about it.
How PsA Weakens Bones
The tough truth: Chronic inflammation from PsA means you are at greater risk for developing osteoporosis. “The inflammatory state is associated with bone loss,” says Linda A. Russell, M.D., a rheumatologist at the Hospital for Special Surgery in New York City. “Some patients with psoriatic arthritis also get spondylitis, a type of arthritis in the spine that causes stiffness. This condition can increase the risk for vertebral fractures.”
Bone loss or weakening caused by PsA goes up with age, according to researchers the University of Erlangen-Nuremberg in Germany, who found that bone erosions in the dominant hand of people with PsA nearly doubled between the ages of 40 and 60. Meanwhile, the number of bone spurs went up from 7.5 to nearly 12.
Other research suggests that psoriasis itself may have an underlying effect on bone. In fact, when researchers compared imaging results from 101 people with psoriatic arthritis, they detected substantially more erosions and bone spurs in those who had psoriasis for at least 20 years compared to those whose psoriasis was less than 10 years in duration.
Load Up on Calcium
Food won’t fix everything (wouldn’t that be nice!), but the right choices can go a long way to keeping your bones strong. Lesson #1: Drink your milk. “Appropriate intake of calcium and vitamin D is important for bone health,” says Dr. Ruderman. If you’re not a milk kind of person, there’s cheese, yogurt, or any other low-fat dairy item.
The good news is that the amount you need is no greater than the national guidelines—it’s just that many people fall short of these figures without making a conscious effort. “Calcium needs are the same for someone with or without PsA,” says Sonya Angelone, R.D.N., a registered dietitian nutritionist and spokesperson for the Academy of Nutrition and Dietetics. “The recommended daily allowance (RDA) for calcium is 1,000 mg for males 19-70 years of age and females 19-50 years of age.” If you’re a woman older than 50 or a man older than 70, aim for 1,200 mg a day.
Looking for the biggest bang for your calcium buck? “Dairy milk has about 300 mg per 8 fluid ounces,” says Angelone. “Fortified non-dairy milks have about 300-500 mg per 8 fluid ounces but check the label since products vary.” You can get an equivalent amount from 1.5 ounces of hard cheese, like cheddar or mozzarella, or one cup calcium-fortified orange juice. If you’re a veggie lover, one cup of cooked kale has about 94 mg.
Choose Foods That Fight Inflammation
Foods that contain omega 3 fatty acids are your friends when it comes to bone health, as they help fight inflammation. “I recommend eating fish like wild salmon or canned sardines, a high-quality olive oil, avocado oil and nut oils,” says Angelone. “Just be sure they are fresh and not rancid—that would turn them into an inflammatory oil.”
And fruits and vegetables that are high in antioxidants like raspberries, blueberries, and spinach, may also help ease PsA symptoms due to their anti-inflammatory effects. “Green leafy vegetables, berries, spices like ginger and turmeric, and green or matcha tea are great options for an anti-inflammatory diet.” says Angelone. Also, “about 25% of people with psoriasis are sensitive to gluten, so people with PsA may feel better avoiding gluten containing foods.”
What not to put into your body? “Alcohol can trigger inflammation,” says Angelone. “People with PsA have been found to have a lower diversity of healthy gut bacteria and lacked certain types of healthful bacteria, and alcohol destroys some good gut bacteria. I recommend avoiding alcohol, but if someone would like to drink occasionally, remember that moderate drinking is one serving per day for women and two servings per day for men.”
When to Call in the Reinforcements
Whole foods should always be your first line of defense, but sometimes, you need a little extra help with bone health, and that can especially be the case with calcium if you are lactose intolerant or just not a big fan of dairy. “When you don’t get enough calcium in your diet or vitamin D through fortified milk, supplements can be helpful in ensuring that you get enough to support your bones,” says Dr. Ruderman. Talk with your doctor to see if you should take calcium and vitamin D supplements.
“Two main types of calcium in supplements are calcium carbonate and calcium citrate,” says Angelone. “Calcium citrate is often better absorbed by older people who do not have as much stomach acid for absorption, or if you’re taking it without food. Calcium carbonate is an antacid so it needs acid for absorption, meaning it’s better when taken with food.”
Because your body can only absorb so much calcium at one time, it’s best to split your supplementation into 500 mg in the morning, and another 500 mg at night.
How Meds Support Strong Bones
It’s the chronic inflammation of psoriatic arthritis that does the greatest damage to your bones, so any medication that can keep it under control is critical. Treatment for PsA is largely the same as the approach for rheumatoid arthritis, meaning a mix of disease-modifying anti-rheumatic drugs (known as DMARDs), immunosuppressants, and biologics (a type of DMARD). In fact, a study in Arthritis Research & Therapy found that PsA patients who received biologics showed measurable improvement in bone structure and strength relative to those without the treatment.
“If you have osteoporosis or osteopenia with an elevated risk of fractures, you should speak to your doctor about medications to help strengthen your bones,” says Dr. Russell. Options, among others, include Didronel and Fosamax (bisphosphonates), Prolia and Xgeva (denosumab), and Forteo and Natpara (parathyroid hormone analogs).
On the other hand, certain meds could have a negative effect. “Some medications can be associated with bone loss such as proton pump inhibitors, SSRIs, certain anti-seizure medications, and all forms of steroid medications like prednisone,” says Dr. Russell. “Whenever possible, these medications should be avoided and substituted with ones that are less likely to cause bone loss.” And of course, whatever you’re taking or thinking of taking, talk with your doctor about it first.
Exercise: Your Ultimate Weapon
It’s good for your health, great for your mind, and can be done for virtually no cost. Tricky part: You’ve got to get up and do it! Joint-friendly, weight-bearing exercises hold the key to keeping bones strong if you’re dealing with PsA. That can include biking, walking, using the elliptical machine, and more. Aim to get 30 minutes of moderate-intensity exercise, three to five days a week.
And don’t forget strength training. “Your exercise program should include weights,” says Dr. Russell. Multiple studies have found that strength training two to three times a week (using moderate weights) can maintain or increase bone mass density over the course of a single year.
Talk with your doctor, who might recommend a physical therapist, about a routine that’s safe and makes sense for you. “Beyond bone health, physical activity is important for any patient with inflammatory arthritis,” says Dr. Ruderman. “It brings cardiovascular benefits, not to mention an overall improvement in quality of life.” And that’s something everyone can use.