Socioeconomic context, distance to primary care and detection of hepatitis C: a French population-based study.

Previous research suggests that hepatitis C detection is lower in rural than in urban areas and depends on geographic accessibility to care. To what extent differences in socioeconomic context could explain these disparities remains unknown. This study assessed the respective influence of the socioeconomic context and of the distance to primary care on the hepatitis C detection rates in a well-defined population of 1,005,817 inhabitants covered by a universal health insurance system in the Côte d'Or and the Doubs areas of France. The 1938 cases of hepatitis C newly diagnosed in the survey area between 1994 and 2001 were included. The patients' 'cantons' of residence were classified into six socioeconomic clusters according to 19 quantitative indicators. Age and sex-standardized hepatitis C detection rate ratios (DRR) for the six clusters were estimated and a multilevel Poisson model investigated whether detection rates varied across clusters after adjusting for distance to the nearest general practitioner. Standardized DRR (95% CI) were higher in both "lower-income urban" and "upper-income urban" clusters and lower in the following clusters: "outer suburb", "industrial rural" and economically "dynamic rural". Adjusting for distance to general practitioner reduced the rate difference between socioeconomic clusters: for a distance to general practitioner equalling 0km (practice in the municipality) and compared to the "upper-income urban" cluster, only the "lower-income urban" cluster had higher DRR. In the six clusters, detection rates decreased as the distance to general practitioner increased (DRR 0.89 95% CI 0.84-0.96 for a 1-km change) but the decrease was more marked in both urban clusters. In this population with good primary care affordability, geographic proximity to general practitioner, rather than socioeconomic context of neighborhood, appeared to be the main factor limiting hepatitis C detection.