Environmental and social factors in rheumatoid factor epidemiology

The effect of social and environmental conditions on the epidemiology of Rheumatoid Factor (RF) in healthy population was studied. For this purpose 2 sample of 828 subject was studied using 5 tests for RF. Our sample included: 419 randomized subjects from a quarter at the outskirts of Bologna (high rate immigration, non homogeneous habits and health background; 409 randomized subjects from one rural small town on the Romagna's hills (no immigration, no change in residence or profession for generations, uniform, habits and health background). These tests included: three on slide with binded human (2) and rabbit (1) IgGs and sheep-cells tests-one on slide (Scat) and the other in tube (W.-Rose by Mizuoka). The most frequent positive test was Scat test, in urban population and one human IgG latex-test in the rural population. No urban subject reacted at the same time to 4 or 5 tests. Associated positive results for 2, 3 or 4 tests are usually observed in rural subjects. These results are the expression of the different and more uniform social and biological background acquired by rural people.