Significant disability and productivity losses from pack-years

The key finding of the study was that smoking duration, or pack-years, is strongly associated with productivity costs: the more pack-years, the higher the productivity costs. Productivity costs are losses to society and employers due to reduced productivity of workers. They are indirectly caused by sickness and loss of working capacity.

Pack-years measure the accumulation of the harms of a lifetime of smoking. They are calculated by multiplying each year smoked by the number of pack of cigarettes smoked per day. The age at which a person started or stopped smoking was less important, according to the researchers.

The productivity costs of those who smoked the most years were several times higher than those who did not smoke. The productivity costs to society for men who had smoked for more than 30 years were €184 427 and €60 765 for employers, compared with €133 615 and €62 305 for women. Lifetime smokers had on average 60% more days of sick pay during their working life than non-smokers.

Smoking cessation is directly reflected in lower productivity costs. "Our research shows that continued smoking is a key determinant of productivity costs. This suggests that the harmful effects of smoking depend on the amount and duration of smoking. Quitting smoking is always worthwhile," says Docent Ina Rissanen.

The study took into account absences of more than 10 days as productivity losses. Smokers can have much shorter absences, so the difference with non-smokers may be even greater. The results for men and women were similar and independent of other lifestyle factors.

"These results should show both society and employers that a lot of money is lost in Finland because of the loss of working capacity due to smoking. To prevent this loss, changes should be made both in legislation and in the workplace," says Rissanen.

"The results should be used in workplaces to target cost-effective measures to maintain working capacity and encourage smoking cessation. They show what kind of financial benefits can be achieved from such measures when workers' absenteeism is reduced," says Marko Korhonen, University Researcher at the University of Oulu Business School.

The results are significant because the productivity costs were calculated using a method that also takes into account potential sources of error.

The study followed 10 650 people in the 1966 Northern Finland birth cohort from the prenatal period until the age of 55. Smoking behaviour was estimated by life-cycle modelling and cumulative exposure by pack-years. Productivity costs were estimated using the human capital method (HCM) and the friction cost method (FCM). In addition, detailed data on care, disability, mortality, education, taxation, occupation and labour market based on national registers were used. A two-part regression model was used to predict productivity costs.

The study was carried out in collaboration with researchers from the Research Unit of Population Health of the University of Oulu Faculty of Medicine and the University of Oulu Business School.

Research: Ina Rissanen, Iiro Nerg, Petteri Oura, Sanna Huikari, Marko Korhonen, Productivity costs of lifelong smoking – the Northern Finland Birth Cohort 1966 study, European Journal of Public Health, 2024; ckae057