Prevalence of Raynaud's phenomenon in 2 ethnic groups in the general population of Estonia.

OBJECTIVE: To compare the prevalence of Raynaud's phenomenon (RP) in 2 genetically different ethnic groups in Estonia: Estonians, who are Finno-Ugric people, and Slavs, who are Indo-European people, and to investigate the risk factors of RP. METHODS: A random sample of 5248 Estonians and 4341 Slavs were surveyed by mail questionnaire (Phase I) for suspected RP. A subsample of 1739 subjects was interviewed and examined (Phase II) to make a formal diagnosis of RP, using the color charts, and to collect additional pertinent information. RESULTS: Of these 1739 subjects examined in Phase II, 226 women and 162 men were diagnosed to have RP. The age adjusted prevalence of RP was significantly higher among Slavs (women 11.4 +/- 1.3%, men 13.0 +/- 1.6%) compared to Estonians (women 7.8 +/- 1.0%, p = 0.023; men 8.2 +/- 1.5%, p = 0.031). Based on logistic regression analysis, the diagnosis of RP among women was associated with a Slavic ethnic origin, the presence of connective tissue disorders or cardiovascular diseases, a family history of RP, a history of dysphagia and frostbite, smoking, and a lower body mass index (BMI). Among men RP was associated with manual work, vibrating tool use, a history of frostbite and injuries to the fingers. older age, and a lower BMI. CONCLUSION: Our results revealed a significant difference in the prevalence of RP between 2 ethnic groups living in the same geographic region. The risk factors associated with RP show considerable sex differences, RP being mostly constitutional in women and occupational in men.