13 october 2020

Association of Alcohol-Induced Loss of Consciousness and Overall Alcohol Consumption With Risk for Dementia

Importance: Evidence on alcohol consumption as a risk factor for dementia usually relates to overall consumption. The role of alcohol-induced loss of consciousness is uncertain. Objective: To examine the risk of future dementia associated with overall alcohol consumption and alcohol-induced loss of consciousness in a population of current drinkers. Design, Setting, and Participants: Seven cohort studies from the UK, France, Sweden, and Finland (IPD-Work consortium) including 131415 participants were examined. At baseline (1986-2012), participants were aged 18 to 77 years, reported alcohol consumption, and were free of diagnosed dementia. DementiaDementia is a form of cognitive impairment where an individual loses the ability to think rememb... was examined during a mean follow-up of 14.4 years (range, 12.3-30.1). Data analysis was conducted from November 17, 2019, to May 23, 2020. Exposures: Self-reported overall consumption and loss of consciousness due to alcohol consumption were assessed at baseline. Two thresholds were used to define heavy overall consumption: greater than 14 units (U) (UK definition) and greater than 21 U (US definition) per week. Main Outcomes and Measures: DementiaDementia is a form of cognitive impairment where an individual loses the ability to think rememb... and alcohol-related disorders to 2016 were ascertained from linked electronic health records. Results: Of the 131415 participants (mean [SD] age, 43.0 [10.4] years; 80344 [61.1%] women), 1081 individuals (0.8%) developed dementia. After adjustment for potential confounders, the hazard ratio (HR) was 1.16 (95% CI, 0.98-1.37) for consuming greater than 14 vs 1 to 14 U of alcohol per week and 1.22 (95% CI, 1.01-1.48) for greater than 21 vs 1 to 21 U/wk. Of the 96591 participants with data on loss of consciousness, 10004 individuals (10.4%) reported having lost consciousness due to alcohol consumption in the past 12 months. The association between loss of consciousness and dementia was observed in men (HR, 2.86; 95% CI, 1.77-4.63) and women (HR, 2.09; 95% CI, 1.34-3.25) during the first 10 years of follow-up (HR, 2.72; 95% CI, 1.78-4.15), after excluding the first 10 years of follow-up (HR, 1.86; 95% CI, 1.16-2.99), and for early-onset (<65 y: HR, 2.21; 95% CI, 1.46-3.34) and late-onset (>/=65 y: HR, 2.25; 95% CI, 1.38-3.66) dementia, Alzheimer disease (HR, 1.98; 95% CI, 1.28-3.07), and dementia with features of atherosclerotic cardiovascular disease (HR, 4.18; 95% CI, 1.86-9.37). The association with dementia was not explained by 14 other alcohol-related conditions. With moderate drinkers (1-14 U/wk) who had not lost consciousness as the reference group, the HR for dementia was twice as high in participants who reported having lost consciousness, whether their mean weekly consumption was moderate (HR, 2.19; 95% CI, 1.42-3.37) or heavy (HR, 2.36; 95% CI, 1.57-3.54). Conclusions and Relevance: The findings of this study suggest that alcohol-induced loss of consciousness, irrespective of overall alcohol consumption, is associated with a subsequent increase in the risk of dementia.

Additional Info

  • Authors

    Kivimaki M.; Singh-Manoux A.; Batty G. D.; Sabia S.; Sommerlad A.; Floud S.; Jokela M.; Vahtera J.; Beydoun M. A.; Suominen S. B.; Koskinen A.; Vaananen A.; Goldberg M.; Zins M.; Alfredsson L.; Westerholm P. J. M.; Knutsson A.; Nyberg S. T.; Sipila P. N.; Lindbohm J. V.; Pentti J.; Livingston G.; Ferrie J. E.; Strandberg T.
  • Published Date

    13 october 2020