Professor Emily Banks is a public health physician and epidemiologist with interest and expertise in large scale cohort studies, pharmacoepidemiology, women’s health, Aboriginal Health and healthy ageing. She is currently the Head of Chronic Disease Epidemiology at the National Centre for Epidemiology and Population Health, Scientific Director of the 45 and Up Study and Chair of the Advisory Committee on the Safety of Medicines. The main emphasis of her work has been in using cohort study methodology to identify potentially modifiable factors affecting individual and population health in different settings and in quantifying their effects, to inform improvements in health and health care.
Background: The smoking epidemic in Australia is characterised by historic levels of prolonged smoking, heavy smoking and very high levels of long-term cessation, with 13% of adults reporting that they smoke daily in 2013. Large-scale quantitative evidence on the relationship of tobacco smoking to mortality in Australia is not available, and has the potential to provide independent international evidence about the contemporary risks of smoking.
Methods: Prospective study of 204,953 individuals aged ≥45 years from the general population of New South Wales (the 45 and Up Study) from 2006-2009, with linked questionnaire, hospitalisation and mortality data to mid-2012. Hazard ratios (RR) for all-cause mortality among current and past smokers compared to never-smokers were estimated.
Results: Overall, 5,593 deaths accrued during follow-up (874,120 person-years; mean: 4.26 years); 7.7% of participants were current smokers and 34.1% past smokers at baseline. Compared to never-smokers, the adjusted RR (95%CI) of mortality was 2.96 (2.69-3.25) in current smokers and was similar in men (2.82 (2.49-3.19)) and women (3.08(2.63-3.60)) and according to birth cohort. Among past smokers, mortality diminished gradually with increasing time since cessation and did not differ significantly from never-smokers in those quitting prior to age 45. Current smokers are estimated to die an average of 10 years earlier than non-smokers.
Conclusions: In Australia, up to two-thirds of deaths in current smokers can be attributed to smoking. Cessation reduces mortality, compared with continuing to smoke, with cessation earlier in life resulting in greater reductions.