Psoriasis and Inflammation

In people without psoriasis, skin cells are shed monthly, and new skin growth occurs to replace what is lost. However, in people with psoriasis, inflammatory processes speed up skin cell growth, a sign of an overactive immune system. The result of these processes is inflammation, which is thought to play a role in the development and continuing effects of psoriasis.

Reducing inflammation throughout the body is an important part of treating psoriasis, reducing symptoms, preventing disease complications, and improving overall health.

This article discusses the role of inflammation in psoriasis as well as symptom management and treatment.

Effects of Inflammation on Psoriasis

Inflammation is the body’s natural response to defend and repair. When a healthy person becomes sick, their immune system triggers inflammation. White blood cells rush in to protect against invaders and repair the damage. When the illness stops (heals), the inflammation stops.

But for people with inflammatory conditions, that inflammation continues. In people with psoriasis, that widespread inflammatory response pushes new skin cell growth before old skin cells have had an opportunity to shed.

New skin cells then push up old cells to the surface leading to plaques and scales. These become visible on the skin’s outermost layer.

The effects of psoriasis don’t always stop at the skin. Up to 30% of people with psoriasis will go on to develop a type of arthritis called psoriatic arthritis (PsA). PsA is a chronic, inflammatory kind of arthritis. The ongoing inflammation wreaks havoc on the joints and areas where the tendons and ligaments connect to bone (the entheses).

Studies have found people with psoriasis are at a higher risk for many different health conditions, including heart attacks, strokes, diabetes, inflammatory bowel disease, and depression. The same inflammatory processes that promote psoriasis also play a role in the development of many of these other very serious conditions. 

Causes

Researchers are unclear about what causes psoriasis. But after many decades of research, most speculate that genetics and the immune system are to blame.

Genetics

Some people will inherit genes that make it more likely for them to develop psoriasis at some point in their lives. If you have an immediate family member with psoriasis, your risk for the condition is much higher than others without a family history of the disease.

This is best shown in twin studies where it has been found that identical twins have a 70% possibility of both carrying the same mutation responsible for psoriasis, while fraternal twins have a 20% possibility of carrying the same gene mutation for the condition.

While studies that look at genes linked to psoriasis are helpful, the genetics of the condition are still very complex. It is still possible to have psoriasis with no family history.

The Immune System 

Psoriasis is an autoimmune disease. Autoimmune conditions are the result of your body attacking itself. With psoriasis, white blood cells called T-cells mistakenly attack skin cells.

These are the same T-cells that are supposed to attack and destroy invading bacteria in infections. But for some reason, they go into overdrive and speed up skin cell production. 

A triggering event may be what causes immune system changes leading to the onset of psoriasis. Common triggering events include chronic stress, infections (especially strep infections), skin injury, and the use of certain medications.

Symptoms

The symptoms of psoriasis vary from person to person and depend on the type of psoriasis. Psoriasis skin plaques can cover small areas or they can cover most of the body.

Some common symptoms of psoriasis are:

• Red, raised, inflamed skin patches
• White-silverish scales or plaques on red skin patches
• Dry skin
• Skin that cracks and bleeds
• Sore skin areas around skin patches
• Itching and burning around skin patches
• Thickened, pitted nails
• Pain and swollen joints

Not everyone with psoriasis will experience all the above symptoms.

Symptom Severity

Most people with psoriasis will experience periods of flare-ups and times where their condition is in remission. 

When psoriasis flares up, you may experience more severe symptoms for days or weeks, but eventually, symptoms clear up and are less noticeable or less severe. And you could go weeks where psoriasis symptoms are mild, and then the condition flares up again.

Sometimes, psoriasis symptoms can disappear completely. When you experience no active symptoms of the condition, you might be in remission. But remission doesn’t mean your symptoms are gone forever; it just means you are currently symptom-free.

Treatment

Psoriasis is a lifelong condition that has no cure. Treating psoriasis is aimed at stopping the inflammation that causes skin cells to regenerate too quickly, managing symptoms, removing scales, and improving a person’s quality of life.

Treatment for psoriasis falls into three categories: topical medicines, phototherapy, and systemic drugs.

Topical Medicines

Topical treatments (applied to the skin) are usually the first treatments given to people whose psoriasis is mild to moderate.

Some topical treatments recommended for psoriasis include:

• Hydrocortisone creams and ointments: You can buy mild topical corticosteroid creams without a prescription. These are helpful for people who have only a few affected skin areas, but you will likely need a prescription if over-the-counter corticosteroids don’t help you.
• Salicylic acid: Salicylic acid is considered a keratolytic (a peeling agent). These topicals can soften and thin out scaly skin. They can also irritate skin and weaken hair follicles, so be careful to not leave salicylic acid products (cleansers, creams, and patches) on too long.
• Coal tar: Coal tar can help to slow down the rapid growth of skin cells and help the skin to become smooth once more. These products can also help bring down inflammation, and reduce itching and scaling. However, coal tar can irritate and dry skin, and can lead to skin sensitivity, so be sure to follow your doctor’s instructions on how to use these products.
• Moisturizers: Daily moisturization is vital to treating psoriasis, reducing itching, and helping skin to heal. Use heavy creams and ointments to lock water into the skin, and products that are fragrance-free.
• Prescription retinoid: Your doctor can prescribe a retinoid ointment made with synthetic vitamin D. They will likely also recommend using a steroid ointment to reduce any skin irritation caused by the retinoid.

It could take several weeks for you to notice improvements in skin symptoms using topical therapies for psoriasis.

For some people, topical treatments are not enough to control their psoriasis symptoms. For example, a person with scalp psoriasis might need special shampoo and an ointment to manage and reduce their symptoms.

Phototherapy

Sunlight has been used to treat a variety of skin conditions going back several thousands of years. Back then, the benefits of ultraviolet (UV) radiation for managing symptoms of psoriasis were not yet known. Doctors today know how valuable the use of machines that shine UV rays on the skin can be.

Phototherapy, also called light therapy, can slow down fast-growing skin cells in people with psoriasis. These treatments can be done at your dermatologist’s office a few times a week. But you also have the option of at-home kits that can be just as helpful.

Different types of phototherapy used to treat psoriasis are:

• Narrowband ultraviolet B (UVB) therapy: This type of light therapy is targeted UVB light. You stand in a lightbox, and light passes over your body. Narrowband UVB therapy is safe for most people, including children, people who are pregnant or breastfeeding, and people with weakened autoimmune systems.
• Broadband UVB therapy: This type of light therapy uses a wider range of UVB light, but it is not used as frequently as narrowband UVB.
• Excimer laser therapy: This type of light therapy can help to reduce red patches by exposing them to targeted UVB rays.
• Psoralen + UVA (PUVA): With PUVA light therapy, you will first be given a psoralen tablet or topical psoralen to be applied to your skin. Psoralen will make skin more sensitive to light. The skin will then be exposed to ultraviolet A (UVA) light, which is believed to penetrate the skin more deeply than UVB light.

A short-term side effect of light therapy is that it can make the skin feel sunburned. A long-term side effect is that it can increase the risk for skin cancer.

Light therapy is not recommended for people who have had skin cancer or have medical conditions that increase the risk for skin cancer. People who have medical conditions or take medicines that make them more sensitive to UV light shouldn’t use light therapy.

Systemic Drugs

If your psoriasis is severe or other therapies have not helped, your doctor might recommend systemic treatments. These therapies are designed to work throughout your entire body and can be very effective for treating psoriasis.

Systemic medicines come with potentially serious side effects, but all the systemic medicines for psoriasis have their benefits too. Your doctor can best explain your treatment options and the risks associated with them.

There are two main types of systemic drugs used to treat psoriasis—non-biologic medicines and biologics. Non-biologics are given as tablets or capsules, and biologic therapies are given by injection or infusion.

Non-Biologic Medicines

Methotrexate and cyclosporine are common non-biologic drug therapies prescribed to people with psoriasis. They can help control psoriasis by suppressing inflammation and slowing down the production of skin cells.

These drugs can affect blood cell production and cause high blood pressure, kidney damage, or liver damage. Do not consume alcohol when using methotrexate or cyclosporine.

Oral retinoids can also be given to treat severe psoriasis. Soriatane (acitretin) is the only oral retinoid available in the United States. It works by reducing skin cell production and is taken daily.

Biologic Medicines

Biologic medicines are designed to reduce inflammation by targeting overactive cells in your immune system. They are only prescribed to people with severe psoriasis who have not responded to or cannot use other treatments. 

Biologics are given by injection or IV infusion. Injections can be done at home, while infusions require you to go to an infusion center or your doctor’s office for treatment.

The Food and Drug Administration (FDA) has approved several different biologic drugs for treating psoriasis. These include:

• Cimzia (certolizumab pegol)
• Cosentyx (secukinumab)
• Enbrel (etanercept) 
• Remicade (infliximab)
• Skyrizi (risankizumab)
• Stelara (ustekinumab)
• Taltz (ixekizumab)
• Tremfya (guselkumab)

If your doctor recommends a biologic drug, you will need to be screened for tuberculosis (TB) and other infectious diseases before you start treatment. You should discuss with your doctor all the short- and long-term side effects and risks associated with biologic drug use.

Your Diet

While the research on diet and inflammation is mixed, many people with psoriasis find that making changes to their diet improves their symptoms. A good place to start is to avoid foods that are thought to increase inflammation. You should also aim to eat more foods that are considered anti-inflammatory.

Foods that are believed to increase inflammation include:

• Refined carbohydrates like white bread and sugary cereals
• Foods containing added sugars like crackers, salad dressings, and sodas 
• Red meats and processed meats
• Trans fats found in foods like baked goods, margarine, frozen pizza, and fried foods

Foods that are part of an anti-inflammatory diet might include:

• Green, leafy vegetables, including spinach and kale
• Nuts like almonds and walnuts
• Olive oil
• Fatty fish, including salmon, mackerel, tuna, and sardines
• Fruits, such as oranges, strawberries, cherries, and blueberries

While there has not been enough research to confirm any direct links between psoriasis flare-ups and what you eat, it is always wise to pay close attention to your experience with psoriasis. If your skin symptoms worsen when you eat certain foods, stop eating those foods. If your psoriasis improves, then that food might not be a trigger for you.

Summary

Psoriasis is an inflammatory skin disease that causes itchy plaques or skin patches to develop on the skin as a result of accelerated skin cell production. These plaques and patches can affect any part of your body, but they commonly appear on the knees, elbows, and scalp.

The driving force behind psoriasis is inflammation, which speeds up skin cell growth. And because of the systemic inflammation in psoriasis, people with the condition might also experience other inflammatory-related health conditions, including heart disease.

There is no cure for psoriasis, but treatment can help reduce symptoms and your risk for related conditions.

A Word From Verywell

Psoriasis inflammation can wreak a lot of havoc on your body and cause many other inflammatory-related conditions. Taking the right steps to reduce inflammation, including taking your treatments as prescribed and eating a healthy diet, can reduce psoriasis symptoms and your risk for other conditions. Your doctor can help recommend a treatment plan based on your symptoms and the severity of your psoriasis.