'Seeking affluent neighbourhoods?' a time-trend analysis of geographical distribution of hospitals in the Megacity of Tehran.

Objective: Access to hospitals in megacities in low and middle income countries might be hampered by travel barriers and distance. We assessed the 'inverse care law' hypothesis: whether hospitals tended to be built in the relatively better-off areas through the time.

Methods: A longitudinal time-series study (1966 to 2011) in Tehran to measure inequality in the distribution of hospital beds. We assessed correlations between the district socioeconomic status and availability of hospital beds via regression analyses, estimated correlation, Gini and concentration indices, and used GIS models to map hospital distributions through time.

Finding: We found a clear relationship between socioeconomic status and number of hospital beds per capita ( P -values <0.05). Gini coefficients were about 0.6 and 0.8 for public and private beds, respectively. A third of the variations in hospital bed distribution was explained by the welfare status of the district. For every extra residential room per capita, 130 to 280 extra beds were observed per ten thousand population at the district level. In 2011, out of 162 hospitals, 110 were located in six districts around the centre and northern part of the city. During the time period only two private hospitals were built in relatively disadvantaged districts.

Conclusion: Over a period of about fifty years new hospitals had been established in the relatively affluent areas of the city and the relationship between socioeconomic status of district with total, private and public beds were direct and intensive. Results indicate the problem of inequality may remain over time and be resistant to policy initiatives and major political changes.