Evaluation of the economic impact of California's Tobacco Control Program: a dynamic model approach.

OBJECTIVE: To evaluate the long-term net economic impact of the California Tobacco Control Program. METHODS: This study developed a series of dynamic models of smoking-caused mortality, morbidity, health status and healthcare expenditures. The models were used to evaluate the impact of the tobacco control programme. Outcomes of interest in the evaluation include net healthcare expenditures saved, years of life saved, years of treating smoking-related diseases averted and the total economic value of net healthcare savings and life saved by the programme. These outcomes are evaluated to 2079. Due to data limitations, the evaluations are conducted only for men. RESULTS: The California Tobacco Control Program resulted in over 700,000 person-years of life saved and over 150,000 person-years of treatment averted for the 14.7 million male California residents alive in 1990. The value of net healthcare savings and years of life saved resulting from the programme was $22 billion or $107 billion in 1990 dollars, depending on how a year of life is discounted. If women were included, the impact would likely be much greater. CONCLUSIONS: The benefits of California's Tobacco Control Program are substantial and will continue to accrue for many years. Although the programme has resulted in increased longevity and additional healthcare resources for some, this impact is more than outweighed by the value of the additional years of life. Modelling the programme's impact in a dynamic framework makes it possible to evaluate the multiple impacts that the programme has on life, health and medical expenditures.

Communication between identical twins: health behavior and social factors are associated with longevity that is greater among identical than fraternal U.S. World War II veteran twins.

BACKGROUND: Longevity is greater for identical twins than for fraternal twins from the same population. Factors that are explanatory for this difference are not known. METHODS: Multivariate survival analysis is applied to current mortality data for 26,974 male twins with known zygosities of the National Academy of Science-National Research Council World War II Veteran Twins Registry, and this analysis is applied to their health and social behavior and personal histories, as collected from two survey questionnaires distributed in 1967 and 1983 (with 14,300 and 9475 responses received, respectively). To explain this difference in longevity, social, health, and personal history factors are evaluated for associations with longevity. RESULTS: Survival functions of identical and fraternal twins differed significantly (p<.0001). Median lifetimes were 82 years for identical and 80.5 years for fraternal twins. The correlation between lifetimes of identical twin partners was greater than that of fraternal twins. For identical but not for fraternal twins, the risk of mortality was significantly lower for twin partners who communicated 1 or more times per month, compared with those who communicated less frequently (relative risk.80, 95% confidence interval 0.68-0.94, p=.008, with control for other factors associated with longevity: smoking, exercise, a current marriage, living with both parents until age 15 or older, and having a live co-twin). Distributions of communication, exercise level, and smoking prevalence were more beneficial with regard to longevity for identical than for fraternal twins as a group. CONCLUSIONS: Frequent communication between identical but not fraternal twin partners, and both level of exercise and prevalence of smoking, distributed more beneficially in terms of longevity for identical compared with fraternal twins, are explanatory for the greater longevity of identical than fraternal twins.