Population-Based Study of Psoriasis in Norway
Title: Psoriasis in Norway as observed in a
population-based Norwegian twin panel.
Authors: Olsen AO, et al.
Publication: Br J Dermatol. 2005 Aug;153(2):346-51.
The authors wanted to evaluate the characteristics of psoriasis
in a population, specifically those related to gender and age.
To do this, they performed a population-based health survey of
psoriasis in Norway in 1998 of Norwegian twins aged 19 to 31 years.
The study was based on self-reported history of psoriasis among
8045 questionnaire responders.
The authors found that 334 people (4.2%) reported a positive
history of psoriasis. Although there was no gender difference
in the overall prevalence of this disease, there was higher prevalence
in teenage girls. The frequency of psoriasis increases with age
in a linear fashion, and peaks at a certain age. This peak age
is lower in females than in males.
The mean age of onset was also lower in females (14.8 years)
compared to males (17.3 years). This suggested that the risk of
developing psoriasis was higher in young females than males –
however, by age 31 the cumulative risk was actually the same for
men and women.
The authors concluded that their study found high levels of frequency
of psoriasis in Caucasian population in north Europe, similar
to that found in previous studies. They also found gender-specific
characteristics of psoriasis, namely the onset of the disease
appeared at a younger age in females.
Editor’s Note: the prevalence of psoriasis in
the world’s population is 1 to 3%, so it is relatively higher