Alcohol consumption in the general population is associated with structural changes in multiple organ systems

Abstract

Background: Excessive alcohol consumption is associated with damage to various organs, but its multi-organ effects have not been characterised across the usual range of alcohol drinking in a large general population sample.

Methods: We assessed global effect sizes of alcohol consumption on quantitative magnetic resonance imaging phenotypic measures of the brain, heart, aorta, and liver of UK Biobank participants who reported drinking alcohol.

Results: We found a monotonic association of higher alcohol consumption with lower normalised brain volume across the range of alcohol intakes (-1.7 × 10^-3 ± 0.76 × 10^-3 per doubling of alcohol consumption, p=3.0 × 10^-14). Alcohol consumption was also associated directly with measures of left ventricular mass index and left ventricular and atrial volume indices. Liver fat increased by a mean of 0.15% per doubling of alcohol consumption.

Conclusions: Our results imply that there is not a 'safe threshold' below which there are no toxic effects of alcohol. Current public health guidelines concerning alcohol consumption may need to be revisited.

Funding: See acknowledgements.

Keywords: alcohol consumption; aorta; brain; epidemiology; global health; heart; imaging; liver; none.

Figure 1.. Flow chart of eligible participants included in analyses.

Figure 2.. Partial residual plots for the imaging-derived phenotypes.

Partial residual plots for (a) normalised brain volume, (b) total grey volume, (c) total white volume, (d) left ventricular mass index, (e) left ventricular end-diastolic volume index, (f) left ventricular ejection fraction, (g) right ventricular end-diastolic volume index, (h) right ventricular ejection fraction, (i) left atrial volume index, (j) right atrial volume index, (k) ascending aortic area index, (l) descending aortic area index, (m) ascending aortic distensibility, (n) descending aborting distensibility, and (o) liver fat.

Figure 3.. Voxel-wise associations of alcohol consumption with brain grey matter volumes (N = 10,143).

Highlighted clusters define regions in which reductions of spatially normalised grey matter volume are inversely correlated with log₂-transformed alcohol consumption (g/d). The analysis suggests higher relative atrophy in the cingulate cortex (light blue arrowheads, A, B), thalamus (green arrowheads, A, C), orbital frontal cortex (red arrowheads, A, D), and insular cortex (dark blue arrowheads, C, D). Broken lines in (A) show levels for axial images in (B–D). The voxel-wise parametric model was adjusted for age, sex, ethnicity, body mass index, college degree education, hypertension, diabetes, and smoking history. The results are displayed on the MRI template available in SPM12 at axial slices of 46.5 mm (B), 6 mm (C), and –7.5 mm (D) relative to the bregma. The calibration bar provides the colour range use to describe t-scores calculated using a family-wise error (FWE)-corrected threshold of p<0.05.