Psoriasis is an autoimmune condition in which symptoms on the skin are caused by inflammation in the body. People who have psoriasis tend to have a higher risk of developing certain other types of health conditions, many of which are also linked to chronic inflammation in some way.
Comorbidities are different conditions that occur in the same person, either at the same time or at different times in the person’s life. In many cases, comorbid conditions interact in some way, or have some of the same causes and/or risk factors. These can be genetic risk factors, and researchers have identified several genes that are related to inflammatory processes seen in psoriasis and other autoimmune diseases8.
The research that identifies the risk of people with psoriasis developing one or more comorbidities comes from observational studies as well as clinical trials. Some of the comorbidities that are linked to psoriasis include:
- Psoriatic arthritis
- Heart disease
- Type 2 diabetes
- Obesity and metabolic syndrome
- Inflammatory bowel disease (including Crohn’s)
How is psoriatic arthritis linked to psoriasis?
Psoriatic arthritis is an autoimmune condition that causes inflammation, swelling, stiffness, and pain in and around the joints. About 30% of patients who have psoriasis of the skin will go on to develop psoriatic arthritis later on, often a decade after first having psoriasis symptoms1. Psoriatic arthritis symptoms appear most commonly in the joints of the fingers and toes.
Read more information about psoriatic arthritis and psoriasis.
How is heart disease linked to psoriasis?
Many studies have shown that people with psoriasis run a higher risk of developing heart disease2. Heart disease, which is also called cardiovascular disease, refers to a set of conditions related to the body’s cardiovascular system. The heart and all of the body’s blood vessels make up the cardiovascular system. People with cardiovascular disease have a higher risk of developing certain types of heart disease, including:
- Coronary artery disease, which can lead to heart attack
- Peripheral arterial disease
- High blood pressure
- Irregular heartbeat
Read more about the link between heart disease and psoriasis.
How is type 2 diabetes linked to psoriasis?
Type 2 diabetes mellitus is a condition that affects the pancreas, which is an organ in the body that produces insulin. Insulin is a substance that helps the body transform sugars in the foods we eat and drink into energy to fuel the body’s functions. People with type 2 diabetes mellitus have levels of sugar (glucose) in the blood that are too high, which can cause a range of symptoms and complications that may be serious. People with psoriasis have a greater chance of developing type 2 diabetes, and that chance increases as the level of psoriasis severity increases3.
Read more about the link between type 2 diabetes mellitus and psoriasis.
How are obesity and metabolic syndrome linked to psoriasis?
Metabolism is the process of converting the food we eat into energy for the body. Metabolic syndrome is the name for a group of symptoms that are related to the disruption of the normal processes of metabolism, including:
- High blood pressure
- High blood sugar
- Low blood levels of HDL cholesterol
- High blood levels of triglycerides (a type of fat)
- Having a large waist, with excess fat carried around the stomach
Together, these symptoms can lead to serious conditions such as diabetes, heart disease, and stroke. Studies have reported that up to 40% of people with psoriasis also have metabolic syndrome4.
Obesity is a condition in which a person has an excess amount of body fat. Healthcare providers use a measurement called the body mass index (BMI) to make a diagnosis of obesity, which is a condition that can lead to complications such as heart disease, diabetes, and high blood pressure. Research suggests that people with psoriasis have more than double the likelihood of being obese than people without psoriasis.
An online resource for calculating your BMI is available here: http://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmicalc.htm
Read more about the link between obesity, metabolic syndrome, and psoriasis.
How is inflammatory bowel disease linked to psoriasis?
Inflammatory bowel disease is the name for a group of conditions in which inflammation in the body causes symptoms along the digestive tract, anywhere from the mouth to the anus. The two main types of inflammatory bowel disease are called ulcerative colitis and Crohn’s disease. Symptoms of those conditions include:
- Abdominal pain and cramping
- Rectal bleeding
- Weight loss
People with psoriasis have a slightly higher risk of developing an inflammatory bowel disease. Researchers think that there may be a genetic link between the two conditions, making members of certain families more likely to develop one or both conditions5.
Read more information about inflammatory bowel disease and psoriasis.
How is depression linked to psoriasis?
Depression is a mental health condition (also called a mood disorder) that can cause a person to feel sad, hopeless, and tired for long periods of time. Having psoriasis can be difficult to cope with and emotionally stressful at times, and people with the condition are more likely to develop depression. For example, one study found that psoriasis patients are more than twice as likely to develop depression than the general population6. Researchers are also learning more about the role that inflammation due to psoriasis may play in depression as well.
Read more about depression and psoriasis.
How is cancer linked to psoriasis?
People with psoriasis have a slightly higher risk of developing certain types of cancer, such as lymphoma and non-melanoma skin cancers. Researchers believe that this may be partly due to the effect of long-term inflammation on the body7. It is very important that psoriasis patients receive regular skin cancer screenings to check for signs and symptoms of these cancers, which are more effectively treated if they are detected early.
Read more information about cancer and psoriasis.
Your treatment plan
People who have psoriasis should be carefully monitored by their healthcare providers for signs and symptoms of any comorbidities or other health conditions so that they can be treated promptly before conditions become more severe. Healthcare providers should provide information about how to reduce your chance of developing complications or other health conditions like those described above. Understanding the risk of developing these conditions is an important part of developing an effective treatment plan. In many cases, comorbidities that are detected early are easier to treat effectively.