Temporal arteritis, polymyalgia rheumatica and cardiovascular risk factors. A prospective multicentric case-control study.

Objectives. - To assess the potential pathogenetic role of cardiovascular r isk factors measured at diagnosis in temporal arteritis, Methods. - Four hundred newly diagnosed patients and their age- and sex-mat ched controls randomly selected from the general population were included i n a prospective multicentric cas-control study. Results. - In female patients, smoking increased the disease risk by a fact or of 6 (95 % CI: 2-17, p = 0.00006), and by a factor of 17 in case of > 10 pack-years. Pre-existing peripheral arterial disease increased the risk by a 4.5-fold factor (95 % CI: 2-11, p = 0.0003), both in patients with a pos itive and those with a negative biopsy. Smoking alone appeared as a risk fa ctor for polymyalgia rheumatica (OR: 3,64, 95 % CI: 1.07 - 12.40). In male patients, none of the cardiovascular risk factors studied was positively as sociated with the disease. Conclusion. - Smoking and a pre-existing peripheral arterial disease are in dependently associated with temporal arteritis in women, Risk factors for d isease with an imbalanced sex ratio should be studied separately for each s ex in matched case-control studies in order to avoid matching bias.