Health Complications of Psoriasis

6 Reasons Why Psoriasis Is More Than Skin Deep

Most people consider psoriasis to be a skin condition, a belief that minimizes the great harm the autoimmune disease can cause. While skin lesions (called plaques) are characteristic of the disease, the systemic inflammation that causes plaques can affect multiple organ systems as well.

If left untreated, the inflammation can gradually spread and trigger changes in the nails, joints, eyes, brain, kidneys, heart, pancreas, and blood vessels. This is why the early and appropriate treatment of psoriasis is needed to control inflammation and prevent medical complications that are more than skin deep.

2:07

6 Myths About Psoriasis

Nail Psoriasis

Nail psoriasis is the most common comorbidity (co-existing illness) in people with psoriasis. According to a 2017 review in the journal Psoriasis, no less than 50% of people with psoriasis have signs of nail damage at the time of diagnosis, while 90% experience significant nail changes at some point in their life.

Symptoms of nail psoriasis include:

  • Nail pitting
  • Thickening of the nail plate (subungual hyperkeratosis)
  • Horizontal ridges on the nail (Beau's lines)
  • Yellowish-red dots beneath the nail ("oil drops")
  • White nail patches (leukonychia)
  • Tiny blacks lines beneath the nail caused by burst capillaries (splinter hemorrhages)
  • Lifting of the nail plate (onycholysis)
  • Brittle and crumbling nails
  • Redness in the white arch at the base of the nail (spotted lunula)

With appropriate and consistent treatment, nail psoriasis can clear up within three months in fingernails and six months in toenails.

Psoriatic Arthritis

Psoriatic arthritis can affect from anywhere from 6% to 41% of people with psoriasis, according to a 2015 study from the University of Pennsylvania. Moreover, around 85 % of people with psoriatic arthritis will also have psoriasis.

Symptoms can vary from person to person but may include:

  • Pain, swelling, or stiffness in one or more joints
  • Joint redness and warmth
  • Sausage-like swelling in the fingers or toes (dactylitis)

Psoriatic arthritis is most often asymmetric (only affecting a joint on one side of the body), but can become symmetric (affecting the same joint on both sides of the body) in more severe cases. Psoriatic arthritis may also affect the spine (spondyloarthritis) or cause severe damage to the distal joints (those nearest the nails) of the fingers and toes.

old woman suffering from wrist hand pain, health problem concept
PORNCHAI SODA / Getty Images

Eye Problems

Most of the eye problems associated with psoriasis are caused by blepharitis (inflammation of the eyelid). The condition is caused by the appearance of lesions on or near the eyelid. When this occurs, the eyelid can lift or shift abnormally, causing eye dryness, burning, and itching.

Blepharitis can lead to conjunctivitis (pink eye) and uveitis (inflammation of the pigmented portion of the eye). Without treatment, both conditions can significantly impair eyesight.

Mood Disorders

The very fact that you have psoriasis can cause depression, particularly if symptoms are severe and uncontrolled. But, there is increasing evidence that the disease can alter your brain chemistry in ways that incite significant changes in your mood and cognition.

According to a 2015 review from the University of Iowa, there is evidence that acute psoriasis flares can activate the hormonal complex known as the hypothalamic-pituitary-adrenal (HPA) axis. This can cause the excessive secretion of cortisol, a substance commonly referred to as the "stress hormone."

During acute psoriasis flares, cortisol secretion may increase as much as 100-fold, saturating receptors in the brain associated with mood and cognition.

We know from conditions like Cushing's disease that the excessive secretion of cortisol translates to higher rates of depression, anxiety, irritability, and insomnia, as well as the loss of concentration and memory.  The same may hold true for psoriasis.

There is even evidence, albeit uncertain, that psoriasis may increase the risk of the neuromuscular disorder Parkinson's disease.

Psoriasis Doctor Discussion Guide

Get our printable guide for your next doctor's appointment to help you ask the right questions.

Doctor Discussion Guide Woman

Cardiovascular Disease

There is evidence that severe psoriasis can more than double the risk of cardiovascular disease compared to the general population. Chronic inflammation is believed to be a major player in the development of heart disease, although other factors are known to contribute.

The chronic inflammation associated with psoriasis can cause the thickening of tissues (hyperplasia) in the skin and other organs. When it affects blood vessels, it can trigger the development of atherosclerosis (so-called hardening of the arteries) and hypertension (high blood pressure), both of which are closely linked to heart attacks and stroke.

The inflammatory burden can also affect the pancreas, increasing the risk of diabetes and, in turn, heart disease. In their totality, these factors account for higher rates of cardiovascular disease in people with severe (rather than moderate or mild) psoriasis.

A 2017 review in the International Journal of Molecular Science suggested that severe psoriasis increased the risk of heart attack by anywhere from 20% to 70% and the risk of stroke by 12% to 56%.

Cancer

Psoriasis, like rheumatoid arthritis, has long been associated with an increased risk of lymphoma (a type of cancer affecting white blood cells). Research now suggests that psoriatic inflammation may damage cellular DNA and spur the growth of different types of cancer.

A 2016 study in JAMA Dermatology concluded that psoriasis, as an independent risk factor, increased the risk of the following cancers compared to the general population:

  • Lymphoma (all types): 34%
  • Lung cancer: 15%
  • Non-melanoma skin cancer: 12%

One type of lymphoma, known as cutaneous T-cell lymphoma, occurs at a rate four times that of the general population.

Based on these findings, it is likely that the early and effective treatment of psoriasis can mitigate many of these risks and other comorbidities as well.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Haneke E. Nail psoriasis: clinical features, pathogenesis, differential diagnoses, and management. Psoriasis (Auckl). 2017;7:51-63. doi:10.2147/PTT.S126281

  2. Pasch MC. Nail Psoriasis: A Review of Treatment Options. Drugs. 2016;76(6):675-705. doi:10.1007/s40265-016-0564-5

  3. Ogdie A, Weiss P. The Epidemiology of Psoriatic Arthritis. Rheum Dis Clin North Am. 2015;41(4):545-68. doi:10.1016/j.rdc.2015.07.001

  4. Sankowski AJ, Lebkowska UM, Cwikła J, Walecka I, Walecki J. Psoriatic arthritisPol J Radiol. 2013;78(1):7–17. doi:10.12659/PJR.883763

  5. Nicholas MN, Gooderham M. Psoriasis, Depression, and Suicidality. Skin Therapy Lett. 2017;22(3):1-4.

  6. Connor CJ, Liu V, Fiedorowicz JG. Exploring the Physiological Link between Psoriasis and Mood Disorders. Dermatol Res Pract. 2015;2015:409637. doi:10.1155/2015/409637

  7. Thau L, Sharma S. Physiology, Cortisol. In: StatPearls [Internet]. 2019. 

  8. Ungprasert P, Srivali N, Kittanamongkolchai W. Risk of Parkinson's Disease Among Patients with Psoriasis: A Systematic Review and Meta-analysis. Indian J Dermatol. 2016;61(2):152-6. doi:10.4103/0019-5154.177771

  9. Lopez-Candales A, Hernández Burgos PM, Hernandez-Suarez DF, Harris D. Linking Chronic Inflammation with Cardiovascular Disease: From Normal Aging to the Metabolic SyndromeJ Nat Sci. 2017;3(4):e341.

  10. Chiesa fuxench ZC, Shin DB, Ogdie beatty A, Gelfand JM. The Risk of Cancer in Patients With Psoriasis: A Population-Based Cohort Study in the Health Improvement Network. JAMA Dermatol. 2016;152(3):282-90. doi:10.1001/jamadermatol.2015.4847

Additional Reading

By Dean Goodless, MD
 Dean R. Goodless, MD, is a board-certified dermatologist specializing in psoriasis.