Gender and educational differences in smoking initiation rates in Spain from 1948 to 1992.

BACKGROUND: The pattern of smoking initiation is of importance in understanding the prevalence of smoking and future trends in tobacco-related diseases.
OBJECTIVE: To analyse trends of cigarette smoking initiation rates by sex and educational level in Spain.
METHODS: Pooled data from the 1993, 1995 and 1997 Spanish National Health Interview Surveys were used (16,365 males and 17,478 females aged >15 years). The age and smoking status of each subject were reconstructed for five calendar periods (1948-1952, 1958-1962, 1968-1972, 1978-1982, 1988-1992). Age-specific (10 to 24 years old) smoking initiation rates were calculated for males and females, and according to level of education (high education: university and secondary school; low education: primary and less than primary).
RESULTS: Among males, there was a trend towards earlier age at start of smoking and higher initiation rates between 1958 and 1982, and a subsequent decline in initiation rates, more apparent in males with a higher level of education. Smoking initiation among females was rare until the 1960s, and from the period 1968-1972 onwards a converging pattern with that of males was observed. Women with a higher level of education started smoking before women with low education, but this pattern changed over the period 1978-1982, with higher initiation rates among less educated women during the last period studied.
CONCLUSIONS: These results help to characterize the tobacco epidemic in Spain, now at the end of stage 3. The observations are in agreement with diffusion-of-innovations theory and the social and economic changes from the 1960s onwards in Spain.