Optimizing Canada's low-risk drinking guidelines (LRDG): Examining emergency department visits, hospitalizations, and deaths amongst Canadian drinkers.

Alcohol is the most commonly consumed drug worldwide and is ubiquitous in most societies and cultures. The widespread consumption of alcohol, however, is associated with substantial societal harms and costs. Alcohol consumption contributes significantly to several important health and socials harms. In 2015-2016 alone, there were over 77,000 hospitalizations entirely caused by alcohol in Canada, and more than 5,000 alcohol-related deaths. To help to reduce these harms, many jurisdictions have created low-risk drinking guidelines (LRDG) -suggested daily, single-sitting, and/or weekly drink limits to minimize acute and chronic harms from alcohol consumption. Canada released its LRDG in 2011, which recommends no more than 2 drinks per day, 3 drinks in a single sitting, and 10 per week for women, and no more than 3 per day, 4 drinks in a single sitting, and 15 per week for men. To date, there has been limited research assessing the extent to which Canadians follow these guidelines, and no studies have examined whether following them reduces the likelihood of subsequent alcohol-related health and social harms. To address this gap, this proposed study aims to explore the predictive validity of Canada's LRDG by analyzing acute and chronic outcomes wholly or partially attributable to alcohol in Canadians who: (1) consume alcohol in moderation, as per the guidelines; (2) abstain from drinking (in the past year/lifetime); and (3) those who are at a higher level of risk by exceeding established daily, weekly, or single-sitting drinking guideline limits. International comparison of drinking guidelines from other jurisdictions will be also be performed to further estimate optimal low-risk limits and to improve the accuracy of Canada's LRDG guideline for classifying drinkers at risk of subsequent alcohol-related harms. Results of this study will provide valuable insight and evidence to inform ongoing efforts to improve Canada's low-risk drinking guidelines.