[The impact of changes in age-related and cause-related mortality on life expectancy at birth in the State of Santa Catarina, Brazil, in the 1990s].

This study aimed to analyze the impact of changes in age-related and cause-related mortality on life expectancy at birth in the State of Santa Catarina, Brazil, in the 1990s. Data were obtained from the Mortality Information System (SIM) for the three-year periods 1989/1990/1991 and 1998/1999/2000. Infant mortality rates and specific mortality rates for individuals > or = 1 year of age were calculated by gender and cause of death. The Pollard method was used to disaggregate the contributions by mortality from different causes and in different ages to life expectancy at birth. The age groups that contributed the most to the increase in life expectancy at birth were 0-1 year and > or = 70 years. The causes of death that most contributed to this increase were chronic non-communicable diseases, such as cardiovascular diseases, in the age brackets above 35 years, and neonatal diseases in the < 1-year bracket. Finally, there were a high proportion of deaths from ill-defined causes, indicating that the true cause-related mortality structure in the State is still unknown.