The Link Between Psoriatic Arthritis and IBD

Medically reviewed by Stella Bard, MD

Psoriatic arthritis (PsA) is an inflammatory autoimmune disease that primarily affects the joints and the entheses, the places where tendons and ligaments connect to bone. A primary characteristic of PsA is inflammation that results from an overactive, malfunctioning immune system.

Research has found people with PsA have a higher risk for a range of gastrointestinal (GI) conditions, including inflammatory bowel disease (IBD). IBD is a term used to describe two diseases: Crohn's disease and ulcerative colitis, which cause chronic and damaging inflammation of the GI tract.

In this article, we will discuss the connection between PsA and IBD, the symptoms of IBD, how to manage these coexisting conditions, and more.

Psoriatic Arthritis

PsA can affect anyone of any age, including children, but it often appears between ages 30 and 50. For many, it starts about 10 years after the autoimmune skin condition, psoriasis, which causes red, itchy, scaly patches. However, it is possible to develop PsA first or never develop psoriasis.

PsA is a progressive condition, which will worsen with time. It can develop slowly and cause mild symptoms, or progress rapidly with severe and aggressive symptoms.

Researchers believe PsA is related to genetics and exposure to different environmental factors (infection, illness, toxins, etc.), and both genetics and environmental factors need to exist for the condition to develop.

The most common symptoms of PsA are joint pain, swelling, stiffness, and severe fatigue. Additional symptoms might include:

• Tendon swelling, pain, and tenderness

• Swollen fingers and toes that sometimes resemble sausages, a condition called dactylitis
  

• Reduced range of motion

• Nail changes, such as pitting, discoloration, and nail bed separation

• Eye inflammation and an eye condition called uveitis affecting the middle layer of tissue in the eyeball (uvea)

• Skin involvement, either psoriasis plaques (raised, inflamed, and scaly patches of skin that cause pain and itching) or general skin inflammation, redness, pain, and itching

Psoriatic Arthritis and IBD

People with PsA can develop digestive issues related to IBD. These conditions cause abnormal immune system responses in which the immune system malfunctions and attacks healthy tissues. Persistent and ongoing inflammation can attack the joints and the digestive tract.

Research shows a link between PsA and both Crohn's disease and ulcerative colitis. One 2016 review in the journal Psoriasis found people with psoriasis are more likely to receive an IDB diagnosis. According to the National Psoriasis Foundation, about 30% of people with psoriasis will go on to develop PsA.

Studies generally point to genetic connections and shared inflammation processes in PsA and IBD. Some studies have also found gut microbiome abnormalities (imbalance in the friendly microbes normally present in the gut) can lead to the development of psoriatic comorbidities (conditions that coexist with PsA or psoriasis).

Symptoms of IBD

The GI tract runs from the mouth to the anus. Crohn's disease can affect any part of the GI tract. Ulcerative colitis affects the colon lining and leads to ulcers (internal sores) in the bowel.

The most common symptoms of IBD are:

• Diarrhea

• Bloody stools

• Abdominal pain or cramping

• Appetite loss and weight loss

• Fatigue or lack of energy

A person with IBD may experience some or all of these symptoms. They can be mild or severe.

IBD can lead to serious disease complications that require medical attention. These might include:

• Malnutrition from appetite loss and weight loss

• Colorectal cancer, which is cancer of the rectum or colon

• Fistulas, which are abnormal openings that form tunnels between the bowel wall and other parts of the digestive tract

• An intestinal rupture called a bowel perforation
  

• Bowel obstruction

While rare, IBD can lead to shock, which is life-threatening. Shock is a critical condition brought on by a sudden drop in blood flow in the body. When a person is in shock, their organs do not get enough blood or oxygen. With IBD, blood loss from long episodes of bloody diarrhea can lead to shock.

Managing Both PsA and IBD

If you experience both PsA and IBD, having a dermatologist (a specialist in skin conditions) and a gastroenterologist (a specialist in digestive tract conditions) on your healthcare team is important.

You and your healthcare team can decide what treatments might be right for you based on how severe IBD and PsA symptoms are. Doctors often treat these conditions with similar treatments because of the overlap that exists between them.

Diet

Diet changes can be helpful for managing symptoms of PsA and IBD. This includes a diet low in saturated fats, cholesterol, and simple sugars.

A 2021 report in the journal Nutrients reported on multiple diets used in addition to standard medical therapies in PsA, IBD, and other inflammatory diseases. The report's authors note that Mediterranean (made up of whole grains, legumes, plenty of fruits and vegetables, and healthy fats), vegetarian/vegan, and reduced-calorie/fasting diets have yielded positive results.

Gluten-free diets, which eliminate a protein found in wheat, rye, and barley, and low-FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) diets, which eliminate a certain class of carbohydrates, do not appear to impact IBD symptoms or systemic (all-over) inflammation in the study.

Lifestyle

Other healthy habits can help you feel better, reduce inflammation, and get better results from treatment. For example, it helps to be active, not smoke, and limit your alcohol intake. You should also find ways to manage stress or consider joining a support group to help you better cope with the effects of PsA And IBD.

Medication

Many of the medications used to treat PsA also treat IBD. These include anti-TNF (tumor necrosis factor) drugs such as Humira (adalimumab) and Remicade (infliximab).

The Food and Drug Administration (FDA) has approved the biologic drug Stelara (ustekinumab) for both psoriatic arthritis and Crohn's disease. Another standard treatment between these two conditions is Cimzia (certolizumab pegol).

A 2019 report in the journal Drug Safety found Stelara was safe and effective for people with plaque psoriasis, active psoriatic arthritis, and moderate to severe Crohn's disease.

When to See a Healthcare Provider

Talk to your healthcare provider if you have PsA and experience chronic diarrhea or other IBD symptoms. You should also let your provider know if you experience severe symptoms of PsA, including in the eyes, skin, and other body areas.

Treating PsA can help prevent disease progression and comorbid conditions (occurring at the same time), like IBD and other disease complications.

Summary

Research shows a link between psoriatic arthritis and inflammatory bowel disease. The same abnormal immune response responsible for PsA inflammation can also cause GI inflammation.

Fortunately, both conditions are treatable with the same diet, lifestyle changes, and drug therapies. If you have PsA and start to experience symptoms of IBD, you should reach out to your healthcare provider to determine the source of symptoms and begin managing these conditions right away.

A Word From Verywell

Managing psoriatic arthritis is vital to your health and reducing your risk for conditions like psoriasis, inflammatory bowel disease, and other autoimmune diseases. PsA is also linked to diabetes, high blood pressure, and heart disease.

Work with your doctor to reduce your chance of developing other severe health conditions. Keep your PsA under control, exercise, eat healthy, and don't smoke.

Frequently Asked Questions

Can psoriatic arthritis cause digestive problems?

People with psoriatic arthritis can develop digestive issues, including inflammatory bowel disease. Researchers believe the same inflammatory processes that cause PsA to develop and worsen lead to digestive troubles.

Is psoriatic arthritis linked to Crohn's disease?

The link between Crohn's disease and psoriatic arthritis is strong. Both conditions are linked to inflammation and the same genetic vulnerabilities.

Is inflammatory bowel disease curable?

Inflammatory bowel disease is a lifelong condition without a cure. Treatment can lead to periods of remission where the condition is not active.

Read the original article on Verywell Health.