Association of the California tobacco control program with declines in lung cancer incidence

The California tobacco control program enacted in 1988 has been associated with declines in smoking and heart disease mortality. Since smoking also causes lung cancer, we investigated whether the program was associated with a decline in lung and other cancer incidence.

Age-adjusted incidence rates of lung and bladder cancer (which are caused by smoking) and prostate and brain cancer (which are not) in the San Francisco-Oakland (SFO) Surveillance Epidemiology End Results (SEER) registry and other eight SEER registries from 1975 to 1999 were fitted in multiple regression analyses accounting for the time lag between program implementation and its effects on cancer incidence. Cigarette consumption over time was also analyzed and related to lung cancer incidence.

With a one year lag, the incidence of lung cancer in SFO, relative to eight other SEER registries, fell significantly below that predicted from the pre-1990 rates, by -0.981 (cases/100,000/year)/year (p = 0.001). With a three year lag, the incidence of bladder cancer fell by -0.234 (cases/100,000/year)/year (p = 0.066). No association of the program was observed on prostate or brain cancers in SFO. During the first decade, the Program was associated with about a 6% reduction in lung cancer incidence; state-wide that corresponds to about 11,000 cases avoided.

A comprehensive tobacco control program is associated with a lower incidence of lung cancer.