Doc Talk

Chronic rash that is more than skin-deep

Psoriasis patients need to go for screening as they have twice the risk of metabolic syndrome

"Don't go near him!"

That is what patients with psoriasis, a chronic condition which manifests as thick, red, scaly patches on the skin, often hear in public spaces.

One of my patients said that everyone got out of the condominium pool the minute they saw him entering it.

He now swims only late at night, when there is no one around.

It is disheartening to see people with non-infectious skin diseases, such as psoriasis, shunned and discriminated against in public.


Psoriasis can affect any part of the body, including the scalp and genital regions.

Up to half of psoriasis patients may have nail changes and one-third of them may have painful, swollen joints.

Psoriasis affects about 100 million people worldwide, according to the World Health Organisation.

In Singapore, it affects 1 per cent of the population, or more than 50,000 people.

  • 50,000

    Number of people in Singapore (or 1 per cent) affected by psoriasis.


    Number of people worldwide affected by psoriasis, according to the World Health Organisation.

The condition is non-contagious. But due to poor public awareness and the unsightly appearance of the rash, people with psoriasis are often stigmatised.

In a survey conducted by the Psoriasis Association of Singapore in 2015, about half of the respondents said they would not eat food prepared by people with psoriasis, share a workplace or residence with them, or allow their children to play with them.

I have encountered many patients who have difficulty getting jobs. There is a high chance that they would be rejected when any prospective employer learns about their psoriasis condition.


Mr L, a 52-year-old driver, came to see me recently as his psoriasis had deteriorated in the past few months - the rash was covering more than 20 per cent of his body surface area.

He has had psoriasis for the past 10 years and was previously treated with topical creams and lotions prescribed by his family doctor. However, he did not follow up on the treatment.

He had also not gone for health screening for several years, as he felt well and did not have symptoms such as joint pain.

A heavy smoker who had been puffing about 20 cigarettes a day since his teenage years, he rarely exercised. He also drank alcohol occasionally.

As I was preparing to start him on an oral medication to treat his psoriasis, I did some checks.

I discovered that he had diabetes mellitus, as well as hyperlipidaemia and hypertension.

He was dismayed when I informed him about this.

In recent years, research has greatly advanced our understanding of psoriasis.

We now know that psoriasis is not just a skin disease per se, but one that is associated with nearly twice the risk of metabolic syndrome (a group of cardiovascular risk factors, including hypertension, insulin-resistant diabetes and abdominal obesity), ischaemic heart disease and stroke.

The greater the severity of psoriasis, the higher the risk.

Other conditions that share a link with psoriasis include non-alcoholic fatty liver disease, inflammatory bowel disease and depression.

It is very important for people who have psoriasis to undergo annual health screening and to lead a healthy lifestyle.

At the National Skin Centre, we routinely screen psoriasis patients for metabolic syndrome once a year.

As for Mr L, I encouraged him to exercise regularly, control his diet and quit or, at least, cut down on smoking and alcohol.

He agreed to see his family doctor for treatment and follow-up on his metabolic syndrome.


Although psoriasis is a chronic skin disease with no permanent cure, there are numerous treatment options that offer patients a reasonably good chance of suppressing the disease and leading a normal life.

Topical creams and lotions are used for patients with very mild psoriasis. For those with moderate to severe psoriasis, treatment methods include ultraviolet light phototherapy and oral medication.

The medication contains ingredients that aim to suppress skin inflammation and normalise the growth rate of superficial skin cells, which are both markedly increased in psoriasis.

As these medications carry a potential risk of side effects, such as decreased production of blood cells, kidney problems or liver damage, patients need to go for regular blood tests to check for these effects.

Newer treatments, such as biologic agents that work by blocking specific immune pathways that drive psoriasis, have been proven to be generally effective and safe for most people.

There is, however, a slightly higher risk of infections.

These biologic agents are administered via injections, ranging from once every two weeks to once every three months.

For the patient to continue experiencing its benefits, the treatment needs to be continued long term.

Psoriasis is a serious disease that goes beyond being skin-deep.

Early diagnosis and appropriate treatment tailored to each patient will ultimately make a positive difference to his lifespan and quality of life.

•Dr Eugene Tan Sern Ting is a consultant dermatologist at the National Skin Centre, National Healthcare Group.

A version of this article appeared in the print edition of The Straits Times on May 02, 2017, with the headline 'Chronic rash that is more than skin-deep'. Print Edition | Subscribe