Evidence based on personal interviews with people who have psoriasis, well documented reports to confirm the seasonal connection, and of course a quick google using the word seasonal together with psoriasis will provide you with a huge amount of research into this subject.
Pattern of skin diseases at the National Skin Centre (Singapore) from 1989-1990.Chua-Ty G, Goh CL, Koh SL.
National Skin Centre, Singapore.
At the National Skin Centre, 74,589 new attendances were seen from 1989 to 1990. The M:F ratio was 1:1. The majority of the patients belonged to the 20-39 year age groups (40%). Frequencies of psoriasis (20.4%) and alopecia (17.2%) were higher among Indians; exfoliative dermatitis was higher among Malays (19.72%); and insect bites were higher among Chinese (87%) [P less than 0.05] compared with ethnic distribution (9.9%, 7.6%, and 77.2% respectively) of NSC patient population. Dermatitis (34.2%) and acne (10.9%) were the most common skin disorders seen. The more common dermatoses seen in 1989/90 differ slightly from those reported in 1950s and 1980s; however, the frequencies of contact dermatitis, fungal infection, and insect bite reactions of 5.8%, 10.9%, and 7.6%, respectively, in 1980 have decreased to 4.7%, 5.4%, and 2.3%, respectively, in 1989/90. There was no seasonal variation in the frequency of various dermatoses except for psoriasis, which was more prevalent during the first quarters of 1989 and 1990. Our results showed that the pattern of skin diseases in Singapore is slowly approximating that of developed countries. The changes in the pattern of skin diseases are probably due to improved economic status, better education and hygiene, ready availability of dermatology services, as well as changes in occupational and environmental contactants over the last decade.
But I guess this should suffice as proof?
I've never experienced this, what evidence is this statement based on?
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