The association between population drinking and ischemic heart disease mortality in educational groups

Differential Associations of Alcohol Use With Ischemic Heart Disease Mortality by Socioeconomic Status in the US, 1997-2018

Importance

People with low socioeconomic status (SES) experience greater burden from alcohol-attributable health conditions and mortality at equal levels of alcohol consumption compared with those with high SES. A U-shaped association has been established between alcohol use and ischemic heart disease (IHD), but no study has explored how such an association differs by SES in the US.

Objective

To investigate how the association of alcohol use with ischemic heart disease mortality differs by SES in the general US population.

Design, Setting, and Participants

This cohort study used record-linked, cross-sectional National Health Interview Survey data for US adults aged 25 years and older, covering 1997 to 2018 with mortality follow-up until 2019. Data analysis was performed from March to June 2023.

Exposures

SES (operationalized using education attainment) and alcohol consumption were obtained from self-reported questionnaires.

Main Outcomes and Measures

The outcome was time to IHD mortality or last presumed alive by December 31, 2019. Cox proportional hazard models were applied to evaluate the interaction of SES and alcohol use on IHD mortality, with age as the time scale. Sex-stratified analyses were performed, adjusting for race and ethnicity, marital status, smoking, body mass index, physical activity, and survey year. Fine-Gray subdistribution models were applied to account for competing risks.

Results

This cohort study of 524 035 participants (mean [SD] age at baseline, 50.3 [16.2] years; 290 492 women [51.5%]) found a statistically significantly greater protective association of drinking less than 20 g per day (vs lifetime abstinence) with IHD mortality in the high-SES group compared with the low-SES group (interaction term hazard ratio [HR], 1.22 [95% CI, 1.02-1.45] in men; HR, 1.35 [95% CI, 1.09-1.67] in women). In addition, the differential associations of drinking less than 20 g per day with IHD mortality by SES were observed only among people with less than monthly heavy episodic drinking (HED) (interaction term, HR, 1.20 [95% CI, 1.01-1.43] in men; HR, 1.34 [95% CI, 1.08-1.67] in women); no difference was found in people with at least monthly HED. Among women there was a greater protective association of drinking less than 20 g per day with IHD mortality in the high-SES group than the middle-SES group (interaction term, HR, 1.35 [95% CI, 1.06-1.72]). Among men, the harmful association of drinking more than 60 g per day with IHD mortality in the low-SES group was largely explained by other behavioral risk factors (ie, smoking, body mass index, and physical activity).

Conclusions and Relevance

This cohort study found a greater protective association between drinking less than 20 g per day with less than monthly HED and IHD mortality in the high-SES group compared with the low-SES group, in both sexes even after adjusting for key covariables and behavioral risk factors. The findings suggest that public health interventions on alcohol use should account for different socioeconomic backgrounds when assessing the level of risk related to alcohol exposure, bearing in mind that levels of consumption deemed safe regarding a specific outcome such as IHD may indeed be less safe or not safe across all sociodemographic groups.

The impact of the COVID-19 pandemic on mortality in Sweden-Did it differ across socioeconomic groups?

The characterization of the socioeconomic profile of COVID-19 mortality is limited. Likewise, the mapping of potential indirect adverse outcomes of the pandemic, such as suicide and alcohol abuse, along socioeconomic lines is still meagre. The main aim of this paper is to (i) depict SES-differences in COVID-19 mortality, and (ii) to assess the impact of the COVID-19 pandemic on suicide and alcohol mortality across socioeconomic groups. We used Swedish monthly data spanning the period January 2016-December 2021. We chose education as indicator of socioeconomic status (SES). The following causes of deaths were included in the analysis: COVID-19, all-cause mortality excluding COVID-19, suicide and a composite index of alcohol-specific deaths. SARIMA-modelling was used to assess the impact of the pandemic on suicide and alcohol-specific mortality. Two alternative measures of the pandemic were used: (1) a dummy that was coded 1 during the pandemic (March 2020 and onwards), and 0 otherwise, and (2) the Oxford COVID-19 Government Response Tracker's Stringency Index. There was a marked SES-gradient in COVID-19 mortality in the working-age population (25-64) which was larger than for other causes of death. A SES-gradient was also found in the old-age population, but this gradient did not differ from the gradient for other causes of death. The outcome from the SARIMA time-series analyses suggested that the pandemic did not have any impact on suicide or alcohol-specific mortality in any of the educational and gender groups.