Longitudinal Incidence and Prevalence of Psoriasis

A close-up of bad psoriasis on a person’s arm
Researchers sought to investigate the incidence and prevalence of psoriasis in multiethnic Johor Bahru, Malaysia.

The incidence and prevalence of psoriasis are increasing in Malaysia and vary by ethnicity, sex, and age, according to study findings published in the British Journal of Dermatology.

Lacking population-based epidemiological data on psoriasis in Southeast Asia, researchers sought to investigate the incidence and prevalence of psoriasis in Johor Bahru, Malaysia.

They initiated a population-based cohort study using the Teleprimary Care (TPC®) database from January 2010 through December 2020 that included 3932 patients with dermatologist-confirmed psoriasis — revealing an 11-year prevalence of 0.34% (95% CI, 0.33-0.35) among 1,164,724 Malaysian patients. Prevalence was greater in Indian individuals at 0.54% (95% CI, 0.50-0.58) and Chinese individuals at 0.38% (95% CI, 0.36-0.40) than in Malay individuals at 0.29% (95% CI, 0.28-0.30). The overall incidence in this time span was 34.2 per 100,000 person-years. Incidence, paralleling prevalence, was greater in Indian individuals at 52.5 per 100,000 person-years, and in Chinese individuals at 38.0 per 100,000 person-years than in Malay individuals at 30.0 per 100,000 person-years.

Researchers found prevalence in men/boys of 0.39% (95% CI, 0.37-0.41) greater than in women/girls at 0.29% (95% CI, 0.27-0.30). Through the course of the research timeframe, 2010 to 2020, annual psoriasis prevalence increased steadily from 0.27% to 0.51%; annual rates remained consistently greater among men and Indian individuals. Annual incidence increased from 27.8 to 60.9 per 100,000 person-years during this time span.

Researchers reported that overall, psoriasis was significantly more common among men than women (odds ratio [OR] 1.37; 95% CI, 1.29-1.46) and among Indian and Chinese individuals vs Malay individuals (OR 1.85; 95% CI, 1.71-2.01, and OR 1.30; 95% CI, 1.20-1.41, respectively).

They found a direct relation between prevalence increasing with age with the highest rates in the 50 to 59 year age group (0.67%) and the 60 to 69 year age group (0.66%). There were twin trend peaks in age of psoriasis onset at 20 to 29 years of age and 50 to 59 years of age. Disease onset revealed itself significantly earlier in women (36.8±17.3 years) than in men (42.0±17.2 years) (P <.001), and earlier in Malay individuals (36.4±17.5 years) than Indian individuals (40.8±15.2 years) or Chinese individuals (47.4±16.9 years) (P <.001).

Study limitations include the use of an electronic health database that fails to capture undiagnosed patients and those not actively seeking care, and cases misclassified as incident instead of prevalent.

Researchers concluded that in Malaysia, “psoriasis incidence and prevalence are increasing and varied by age, sex and ethnicity.” They found this upward trend consistent with increasing psoriasis prevalence worldwide.

Disclosure: This research was supported by the LEO Foundation, AbbVie, Almirall, Amgen, Eli Lilly and Company, Janssen, Novartis Pharma AG and UCB. Several study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.


Choon SE, Wright AK, Griffiths CEM, et al; Global Psoriasis Atlas. Incidence and prevalence of psoriasis in multiethnic Johor Bahru, Malaysia: a population-based cohort study using electronic health data routinely captured in the Teleprimary Care (TPC®) clinical information system from 2010 to 2020: classification: epidemiology. Br J Dermatol. Published online July 13, 2022. doi:10.1111/bjd.21768