Snus use and mortality : associations, potential mechanisms, and socioeconomic aspects

• Main Author: Byhamre, Marja Lisa
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Umeå universitet, Allmänmedicin 2022
• Subjects: snus; Swedish snuff; smokeless tobacco; mortality; cardiovascular; cancer; risk factor; metabolic syndrome; C-reactive protein; vitamin D; testosterone; Public Health; Global Health; Social Medicine and Epidemiology; Folkhälsovetenskap; global hälsa; socialmedicin och epidemiologi; Northern Sweden
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-200748

Snus is a smokeless tobacco product made of a moist powder of ground tobacco. It is used mainly in the Nordic countries, although increasingly popular internationally. The Swedish snus tradition dates back to the seventeenth century, and it is now used daily by about 23% of the male and 6% of the female population. Snus contains high levels of nicotine as well as carcinogenic substances and microorganisms that could potentially cause adverse health effects. The physiological effects of snus use include acutely raised blood pressure and heart rate, and increased cardiac oxygen demand, while the psychological response results in alertness and anxiety reduction. The high nicotine content causes rapid onset of addiction. Previous research on snus use and health is largely inconclusive, but indicates increased risks of all-cause, cardiovascular and cancer mortality. This thesis aimed to further investigate the health effects of snus use, with a focus on mortality, potential underlying mechanisms, and the impact of socioeconomic factors. Four original papers form the base of this thesis. The first study was performed on a pooled dataset of eight Swedish cohorts (The Swedish Collaboration on Health Effects of Snus use), including over 169 000 men. We found an increased risk of all-cause (HR 1.28, 95% CI 1.20; 1.35), cardiovascular, and other cause mortality, and indications of raised cancer mortality. The second study was set within an interventional program in northern Sweden (Västerbotten Intervention Programme) and included 46 000 men and women. It showed increased mortality overall (estimates similar to first study), from cardiovascular diseases, and external causes (e.g., accidents and suicide) that remained after controlling for socioeconomic status. We found these associations in groups of varying socioeconomic background (e.g., both basic education and high-income groups), suggesting that increased mortality risks among snus users are not restricted to certain socioeconomic groups. Studies three and four ...