Background: The aims of this study were to describe social inequalities in mortality amongst Basic Health Areas in Barcelona Spain and to analyze the patterns of social inequalities in health.
Methods: This is an ecological study of all deaths of residents in Barcelona in 1989-93. The unit of analysis was the Basic Health Area. Socio-economic and mortality indicators (overall mortality and the main causes of death) were studied. Relative risk estimates between socio-economic and mortality indicators were calculated through Poisson regression models.
Results: An unequal socioeconomical and mortality distribution was observed between areas. The following variables were found to be associated with lower socio-economic conditions: overall mortality (RR = 1,48, males), specific mortality: malignant neoplasm of trachea, bronchus and lung (RR = 1, 64, males), chronic liver disease and cirrhosis (RR = 2,33, males), AIDS (RR = 3,42, males and females), drug overdose (RR = 5,18, males and females), tuberculosis (RR = 6,3, males and females), pneumonia, bronchitis, emphysema and asthma (RR = 1,41, males), and external causes (RR = 2,29, males). The increase in risk with deteriorating socioeconomic situation was linear for cirrhosis and bronchitis, emphysema and asthma, and close to linearity for malignant neoplasm of trachea, bronchus and lung. For AIDS, drug overdose, and tuberculosis, the increase in risk was not linear, being much higher for those areas with higher levels of unemployment.
Conclusions: All causes of death that have been found to be associated with social inequalities are related with life-styles (smoking, excessive alcohol consumption and parenteral drug use). There are two patterns of social inequalities in health: AIDS, drug overdose and tuberculosis stand out as pathologies associated to extreme unfavourable socioeconomic situation, for which it is likely that there are some conditions favouring health problems associated with margination.