Weight Concerns and Abdominal Obesity among Ever-Smokers: a Population-Based Study of Finnish Adults

Smoking-specific weight concerns are one factor involved in smoking and the smoking cessation process. Previous literature has reported inconsistent findings regarding the association of weight concerns with self-efficacy and motivation to quit. In addition, inconsistent findings about smoking-specific weight concerns as an obstacle for quitting have been reported. Even though daily smokers tend to weigh less, they tend to have more abdominal obesity than never smokers. This thesis aimed to assess the level of smokingspecific weight concerns according to smoking status, the association of weight concerns with self-efficacy and motivation to quit, and weight concerns as a predictor of subsequent smoking status in the Finnish adult population. An additional aim was to assess the association of smoking with abdominal obesity. This thesis is based on national FINRISK/DILGOM studies conducted in 2007 and 2014. Four different datasets were used in this study. In 2007, a population-based sample of 10,000 Finnish people (67% participation rate) aged 25 to 74 years from six geographical regions was drawn from the Population Register to form FINRISK 2007. FINRISK 2007 data was used in Study IV. DILGOM 2007, a subsample of FINRISK 2007, was formed to study metabolic factors and obesity. Studies I and II utilised a special sub-sample of ever smokers identified within the DILGOM 2007 study. A sub-sample of ever smokers and follow-up DILGOM 2014 was used in Study III. Smoking status was mainly self-reported, with biochemically-verified data among sub-samples. Weight concerns were measured by a modified Weight Concern Scale administered in the 2007 questionnaire, and nicotine dependence by the Fagerström Test for Nicotine Dependence (FTND). Self-efficacy and motivation to quit, as well as the majority of confounders, were also self-reported measures. Weight, height, waist circumference, and expired air carbon monoxide were measured by study nurses. Cotinine, a metabolite of nicotine, was derived from blood samples. Daily smokers were found to have higher levels of weight concerns compared to occasional smokers, recent quitters, and former smokers. Among daily smokers, weight concerns were associated with lower self-efficacy to quit but not with lower motivation to quit. Nicotine dependence attenuated the association between weight concerns and self-efficacy to quit. Baseline weight concerns predicted smoking cessation and reduced tobacco usage by 2014 (from daily smoking to occasional use) among those daily smokers with low nicotine dependence (FTND 0–3), but not among those with high nicotine dependence (FTND ≥4). The association of smoking status with abdominal obesity was significant among women who were overweight/obese heavy daily (≥20 cigarettes per day) or ex-smokers. Daily smokers report more weight concerns compared to other ever smokers. Weight concerns are associated with a lower self-efficacy to quit among daily smokers. Weight concerns predict subsequent smoking status only among smokers who are not highly dependent on nicotine. Hence, in the Finnish population, weight concerns seem to have a role in some factors involved in the smoking cessation process. However, considering 6 successful cessation as the outcome, those concerns seem to interplay with nicotine dependence. Among overweight/obese women, daily heavy smokers and ex-smokers have more abdominal obesity compared to never smokers. Further investigations in clinical settings, including longitudinal designs and repeated measurements during the smoking cessation process, may be useful to provide a deeper understanding of the complex interplay between weight concerns and other determinants of smoking cessation.