SEASONAL-VARIATION OF ENDOGENOUS UVEITIS IN SOUTH-WESTERN FINLAND

Purpose: To evaluate if there is a seasonal pattern to the incidence o f endogenous uveitis in south-western Finland with special reference t o acute anterior uveitis. Methods: The incidence rates per month of th e 414 new uveitis cases from years 1980-82 and 1988 in the district of Turku University Hospital were calculated. The months of the year wer e grouped into warm (June to September), transitional (April, May, Oct ober, November), and cold (December to March) seasons based on the mea n air temperature of the months in Turku. Results: We observed a stati stically significant increase in the incidence of all uveitis cases in the warm and transitional seasons compared with the cold season (p=0. 030 and p=0.008 respectively). A similar seasonal trend was found amon g anterior uveitis cases, but not among the intermediate, posterior or panuveitis cases. The incidence of acute anterior uveitis cases was h igher in the transitional than in the cold season (p=0.025). No season al variation of the incidence was found in the subgroup of acute anter ior uveitis where ankylosing spondylitis had been confirmed (p=0.70). Conclusion: The present data suggests that there is seasonal variation of the incidence of uveitis in south-western Finland.