Geoepidemiology and space-time analysis of Primary biliary cirrhosis in Crete, Greece

Liver Int. 2014 Aug;34(7):e200-7. doi: 10.1111/liv.12479. Epub 2014 Mar 7.

Abstract

Background & aims: The prevalence of Primary biliary cirrhosis varies in different geographical areas. This might reflect genetic or environmental risk factors. We aimed to define Primary biliary cirrhosis prevalence and incidence, describe patient's spatial distribution, generate prediction maps and detect any possible routing pattern of time-spatial appearance of the disease in Crete, Greece.

Methods: From 1990-2010, 245 Primary biliary cirrhosis patients diagnosed and followed up at the Gastroenterology Department of the University Hospital and the District Hospitals of the island, were contacted and 222 were included in the time-spatial analysis. To map their spatial distribution per 5-year periods, geospatial models were applied in Gis-ArcMap 9.3 software. Kriging Interpolation methods were used to generate prediction maps for the disease in Crete. Areas of high and low probability of disease occurrence were estimated through multicriteria modelling. The disease route was defined by Gis-ArcMap's toolbox.

Results: Prevalence was found to be 365 cases per million, with a mean incidence of 20.88 (range 3.79-35.99). Prediction map estimates from 1.22 to 11 patients per 50 km2 all over Crete. Areas of high risk of disease occurrence are located in the Eastern part, while low risk in the Western part of the island.

Discussion: Prevalence and incidence of Primary biliary cirrhosis in Crete are among the higher published in Europe. Given the homogeneous and stable study population and the geopolitics of the island, the heterogeneity in the time-spatial distribution and the route of disease appearance strongly suggest a role for environmental causative agents.

Keywords: PBC; geoepidemiology; space-time analysis.

Publication types

  • Historical Article

MeSH terms

  • Demography
  • Geographic Information Systems
  • Geographic Mapping
  • Geography
  • Greece / epidemiology
  • History, 20th Century
  • History, 21st Century
  • Humans
  • Incidence
  • Liver Cirrhosis, Biliary / epidemiology*
  • Liver Cirrhosis, Biliary / history*
  • Prevalence
  • Risk Factors
  • Spatio-Temporal Analysis