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

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.

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.

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.

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.