Socioeconomic differences in alcohol habits, alcohol-related disorders and mortality

The overall aim of this thesis is to enhance knowledge about stability and predictors of change in alcohol habits among different sociodemographic subgroups, and to assess the contribution of alcohol use to social differences in alcohol-related disorders and all-cause mortality. Furthermore, as examples of exposure to stressful life events, we examine how parental separation in childhood and separation from partner in adulthood affect alcohol habits over time. This research is approached in four observational studies (Study I-IV), using data from two general population survey cohorts from Stockholm County, Sweden during the first decade of the 21st century.

The findings from Study I show an overall modest contribution of gender to variability in pattern of change in drinking, and that increasing age predicted more stable pattern of drinking. When we measured level of consumption, self-employed women stood out, showing more risky normal weekly alcohol consumption, which was also stable over time. Socioeconomic position did not predict change in alcohol habits for the measurement of AUDIT but low educational level and self-employment predicted change in the normal weekly alcohol consumption. Study II and III confirm that there are social differences in alcohol-related disorders and in all-cause mortality. In addition, social inequalities in alcohol use were found to contribute to the socioeconomic position differences in alcohol-related disorders and all-cause mortality; this was most evident when we examined frequencies of heavy episodic drinking. In Study IV, parental divorce in childhood was found to affect the individual’s alcohol habits throughout life, whereas separation in adulthood has a shorter effect on and a stronger association with alcohol habits during the years after the event. These observations did not differ by gender, age or length of education.

The main conclusion of this thesis is that socioeconomic differences in alcohol use partly explain the health inequalities in alcohol-related harm and all-cause mortality found in Sweden. Furthermore, use of measures of both levels and patterns of drinking is recommended when assessing the impact of alcohol on social inequalities in alcohol-related harm or all-cause mortality, so as not to underestimate the role of alcohol use in differences between socioeconomic groups. Reduced social inequalities in alcohol-related morbidity and all-cause mortality could in principle be achieved if the social differences in heavy episodic drinking were reduced in the general population. Moreover, there is a need to monitor the growing group of self-employed, since this group was found to practice stable risky alcohol habits, and are potentially more vulnerable due to less social security as self-employed.

List of scientific papers

I. Syden L, Wennberg P, Forsell Y, Romelsjo A. Stability and change in alcohol habits of different socio-demographic subgroups - a cohort study. BMC Public Health. 2014;14:525.
https://doi.org/10.1186/1471-2458-14-525

II. Syden L, Sidorchuck A, Makela P, Landberg J. The contribution of alcohol use and other behavioural, material, and social factors to socioeconomic differences in alcohol-related disorders in a Swedish cohort. [Submitted]

III. Syden L, Landberg J. The contribution of alcohol use and other lifestyle factors to socioeconomic differences in all-cause mortality in a Swedish cohort. [Accepted]
https://doi.org/10.1111/dar.12472

IV. Syden L, Forsell Y, Wennberg P. Separation in childhood and adulthood and the development of alcohol habits in a Swedish cohort of adults. [Manuscript]