Effect of total plasma homocysteine on cervical dysplasia risk

We investigated whether total plasma homocysteine (tHcy) is associated with risk for cervical intraepithelial neoplasia (CIN). tHcy was evaluated, alo ng with numerous risk factors for CIN and biochemical indexes of nutrients, in a previously reported study population of 294 subjects with CIN and 170 female controls without GIN. tHcy was significantly higher in cases than i n controls (9.1 vs. 8.3 mu mol/l, p = 0. 002). Human papillomavirus type 16 infection [odds ratio (OR) = 6.7], oral contraceptive use (OR = 6.0), pari ty (OR = 2.2), and cigarette smoking (OR = 1.9) were significantly associat ed with CIN after adjustment for each other and for age, number of sexual p artners, and plasma tHcy, folate, iron, and zinc. Human papillomavirus type 16 positivity increased risk for CIN more when tHcy was >9.12 mu mol/l (OR = 4.7) than when it was less than or equal to9.12 mu mol/l (OR = 3.0). Cig arette use increased risk for CIN when tHcy was >9.12 mu mol/l (OR = 3.9), but not when tHcy was less than or equal to9.12 mu mol/l (OR = 1.5). Parity increased risk for CIN more when tHcy was >9.12 mu mol/l (OR = 4.0) than w hen tHcy was less than or equal to9.12 mu mol/l (OR = 2.0). These results s uggest that elevated plasma tHcy is a risk factor for cervical dysplasia an d that it enhances the effects of other risk factors. It is unknown whether tHcy is sewing as a marker of folate deficiency or is acting through other mechanisms.