Alcohol consumption has long been a topic of public health interest, particularly concerning its effects on older adults. A recent cohort study published in JAMA Network Open examines the associations between alcohol consumption patterns and 12-year mortality, focusing on potential modifications by health-related and socioeconomic risk factors. This article delves into the findings, exploring how different drinking patterns—including wine preference and drinking during meals—affect mortality rates among older adults.

Alcohol Consumption Patterns and Mortality

General Findings

The study analysed data from 135,103 older drinkers from the UK Biobank cohort, with participants classified into four categories based on their mean alcohol intake: occasional, low risk, moderate risk, and high risk. The results showed that even low-risk drinking was associated with higher mortality among older adults with health-related or socioeconomic risk factors.

Over a median follow-up of 12.4 years, the study recorded 15,833 deaths, including 7,871 cancer deaths and 3,215 cardiovascular disease (CVD) deaths. Compared to occasional drinking, low-risk drinking was associated with a higher risk of cancer mortality (Hazard Ratio [HR], 1.11; 95% Confidence Interval [CI], 1.01-1.22). Moderate-risk drinking was linked to higher all-cause (HR, 1.10; 95% CI, 1.03-1.18) and cancer mortality (HR, 1.15; 95% CI, 1.05-1.27). High-risk drinking was associated with elevated all-cause (HR, 1.33; 95% CI, 1.24-1.42), cancer (HR, 1.39; 95% CI, 1.26-1.53), and CVD mortality (HR, 1.21; 95% CI, 1.04-1.41).

Impact of Health-Related Risk Factors

Health Deficits and Frailty

Health-related risk factors were assessed using the frailty index (FI), which considered 49 health deficits. Participants were classified as prefrail or frail if their FI score exceeded 0.12. The study found that even low-risk drinkers with health-related risk factors had higher cancer mortality (HR, 1.15; 95% CI, 1.01-1.30). Moderate-risk drinkers with these risk factors had heightened all-cause (HR, 1.10; 95% CI, 1.01-1.19) and cancer (HR, 1.19; 95% CI, 1.05-1.35) mortality.

Socioeconomic Risk Factors

Socioeconomic Deprivation

Socioeconomic risk was measured using the Townsend deprivation index (TDI). Participants living in more deprived areas (TDI >0) were considered at socioeconomic risk. The study revealed that low-risk drinkers with socioeconomic risk factors had higher all-cause (HR, 1.14; 95% CI, 1.01-1.28) and cancer mortality (HR, 1.25; 95% CI, 1.04-1.50). Moderate-risk drinkers with these risk factors also showed elevated all-cause (HR, 1.17; 95% CI, 1.03-1.32) and cancer mortality (HR, 1.36; 95% CI, 1.13-1.63).

The Role of Wine Preference and Drinking During Meals

Attenuation of Mortality Risk

The study also examined the impact of wine preference and drinking only during meals on mortality. It found that these drinking patterns were associated with lower all-cause mortality in participants with health-related (wine preference: HR, 0.92; 95% CI, 0.87-0.97; drinking only during meals: HR, 0.93; 95% CI, 0.89-0.97) and socioeconomic risk factors (wine preference: HR, 0.84; 95% CI, 0.78-0.90; drinking only during meals: HR, 0.83; 95% CI, 0.78-0.89).

Cancer and CVD Mortality

Drinking only during meals was linked to lower cancer mortality in participants with health-related (HR, 0.92; 95% CI, 0.86-0.99) or socioeconomic risk factors (HR, 0.85; 95% CI, 0.78-0.94). Additionally, wine preference was associated with reduced cancer mortality in individuals with socioeconomic risk factors (HR, 0.89; 95% CI, 0.80-0.99). Drinking only during meals was associated with lower CVD mortality in participants with socioeconomic risk factors (HR, 0.86; 95% CI, 0.75-1.00).

Methodological Approaches

Preventing Selection Bias

To mitigate selection bias, the study used occasional drinkers instead of abstainers as the reference group. This approach helped avoid the abstainer bias, where the apparent lower mortality of light drinkers compared to abstainers could be due to the higher death risk of former drinkers who quit alcohol due to poor health.

Addressing Reverse Causation

The study excluded deaths occurring in the first two years of follow-up to reduce reverse causation. Additionally, the analyses adjusted for numerous sociodemographic, lifestyle, and clinical variables to minimise residual confounding.

Implications for Public Health

Inequalities in Health Outcomes

The study identified significant inequalities in the detrimental health outcomes associated with alcohol consumption. These findings suggest that public health strategies must address these disparities to reduce the high disease burden of alcohol use.

Reevaluating Drinking Guidelines

The results challenge the notion that low to moderate alcohol consumption has protective health benefits. The study’s findings align with growing evidence questioning the assumed benefits of low alcohol intake, particularly for older adults with health-related or socioeconomic risk factors.

Source:
JAMA Network Open