Factors determining high-sensitivity C-reactive protein values in the Spanish population. Di@bet.es study Gemma Rojo-Martı´nez *,† , Federico Soriguer *,† , Natalia Colomo †,‡ , Alfonso Calle § , Alberto Goday ¶ , Elena Bordiu ´ ** , Elı´as Delgado †† , Edelmiro Mene ´ ndez †† , Emilio Ortega *,‡‡ , Ine ´ s Urrutia *,§§ , Juan Girbe ´s ¶¶ , Luis Castan ˜o *,§§ , Miguel Catala ´ *,*** , Sonia Gaztambide *,§§ and Sergio Valde ´s *,† On behalf of the di@bet.es study group 1 * Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain, † Department of Endocrinology and Nutrition, Hospital Universitario Carlos Haya, Ma ´ laga, Spain, ‡ Rı ´o Hortega, Clinical Research Program of the Instituto de Salud Carlos III, Madrid, Spain, § Department of Endocrinology and Nutrition, Hospital Universitario S. Carlos de Madrid, Madrid, Spain, ¶ Department of Endocrinology and Nutrition, Hospital del Mar, Barcelona, Spain, ** Laboratorio de Endocrinologı´a, Hospital Universitario San Carlos de Madrid, Madrid, Spain, †† Department of Medicine, Endocrinology and Nutrition, Hospital Universitario Central de Asturias (HUCA), University of Oviedo, Oviedo, Spain, ‡‡ Endocrinology and Diabetes Unit, Hospital Clı ´nic de Barcelona, Barcelona, Spain, §§ Diabetes Research Group, Hospital Universitario de Cruces, UPV-EHU, Baracaldo, Spain, ¶¶ Diabetes Unit, Hospital Arnau de Vilanova, Valencia, Spain, *** Department of Medicine and Endocrinology, Hospital Clı´nico Universitario de Valencia, Valencia, Spain ABSTRACT Background Although high-sensitivity C-reactive protein (hs-CRP) is currently used as a risk marker of cardiovascular disease, it has been suggested that genetic, clinical, biochemical or environmental factors could modify hs-CRP levels. The aim of this study was to investigate sources of interindividual hs-CRP variability in the Spanish population. Materials and methods A representative sample of the Spanish population within the di@bet.es study was used. Study variables included a clinical and demographic structured survey, a lifestyle survey, a physical exami- nation, plasmatic hs-CRP and other biochemical parameters. Results Median and interquartile range of plasma hs-CRP values were 1Æ73 ± 2Æ75 mg ⁄ dL. Thirty per cent of the study population had hs-CRP levels above 3 mg ⁄ dL and 38% from 1 to 3 mg ⁄ dL. Body mass index was the strongest factor associated with moderate and high hs-CRP levels. Age, sex, waist-to-hip ratio, weight increase, plasma lipid levels, glucose metabolism (HOMA-IR and abnormal glucose regulation categories), pharmacologi- cal treatment (lipid-lowering agents, psychotropic drugs and levothyroxine), smoking, physical activity, different dietary patterns, quality of life and educational level were all significantly associated with hs-CRP levels. Inter- actions were observed between variables. These interactions modulated the effect of previously described factors on hs-CRP. Conclusions Thirty per cent of the Spanish population have hs-CRP levels considered to represent a cardiovascular risk. Different clinical, anthropometric, biochemical and environmental variables modulate hs-CRP levels. In addition, multiple interactions between variables complicate the interpretation of hs-CRP values. Keywords High-sensitivity C-reactive protein, population values, diabetes, cardiovascular risk factors. Eur J Clin Invest 2013; 43 (1): 1–10 1 Members of the di@bet.es study group are present in Appendix. European Journal of Clinical Investigation Vol 43 1 DOI: 10.1111/eci.12002 ORIGINAL ARTICLE