BACKGROUND: Research has long found 'J-shaped' relationships between alcohol consumption and certain health outcomes, indicating a protective effect of moderate consumption. However, methodological limitations in most studies hinder causal inference. This review aimed to identify all observational studies employing improved approaches to mitigate confounding in characterizing alcohol-long-term health relationships, and to qualitatively synthesize their findings.
METHODS: Eligible studies met the above description, were longitudinal (with pre-defined exceptions), discretized alcohol consumption, and were conducted with human populations. MEDLINE, PsycINFO, Embase and SCOPUS were searched in May 2020, yielding 16 published manuscripts reporting on cancer, diabetes, dementia, mental health, cardiovascular health, mortality, HIV seroconversion, and musculoskeletal health. Risk of bias of cohort studies was evaluated using the Newcastle-Ottawa Scale, and a recently developed tool was used for Mendelian Randomization studies.
RESULTS: A variety of functional forms were found, including reverse J/J-shaped relationships for prostate cancer and related mortality, dementia risk, mental health, and certain lipids. However, most outcomes were only evaluated by a single study, and few studies provided information on the role of alcohol consumption pattern. CONCLUSIONS: More research employing enhanced causal inference methods is urgently required to accurately characterize alcohol-long-term health relationships. Those studies that have been conducted find a variety of linear and non-linear functional forms, with results tending to be discrepant even within specific health outcomes.
TRIAL REGISTRATION: PROSPERO registration number CRD42020185861.
BACKGROUND: The dose-response association between alcohol consumption and the subsequent pancreatic cancer risk by individuals' glycaemic status is unclear.
RESEARCH DESIGN AND METHOD: This large-scale nationwide cohort study included 9,514,171 adults without cancer who underwent health examinations under the Korean National Health Insurance Service in 2009 and were followed-up until December 2017 for pancreatic cancer development. Multivariable Cox proportional hazards regression analysis was performed.
RESULTS: During a median follow-up period of 7.3 years, 12,818 patients were newly-diagnosed with pancreatic cancer. Among individuals with normoglycemia, a J-shaped association was observed between the frequency of alcohol consumption (1-2 and >/=5 days/week: hazards ratio [HR]; 95% CI, 0.91; 0.85-0.97 and 1.13; 1.002-1.27, respectively) and pancreatic cancer risk, after adjusting for potential confounders. However, in patients with impaired fasting glucose (IFG), pancreatic cancer risk increased with increased frequency and average daily amount of alcohol consumption (all P for trend <0.01). IFG combined with heavy alcohol consumption (30 g/day) was associated with 38% increased pancreatic cancer risk (HR, 1.38; 95% CI, 1.23-1.54). Diabetes was associated with an increased pancreatic cancer risk regardless of alcohol consumption and 70% increased risk even in non-drinkers (HR, 1.70; 95% CI, 1.61-1.80).
CONCLUSIONS: The J-shaped dose-response association between alcohol consumption and pancreatic cancer risk was observed only in individuals with normoglycemia, not in patients with IFG and diabetes. Complete alcohol abstinence may help reduce pancreatic cancer risk in patients with IFG and diabetes.
BACKGROUND: In the context of increasing global aging, the long-term effects of alcohol consumption on cognitive function in older adults were analyzed in order to provide rationalized health recommendations to the elderly population.
METHODS: The study used the Chinese Longitudinal Healthy Longevity Survey (CLHLS) dataset, from which 5354 Chinese seniors aged 65-112 years were selected as the subjects, spanning the years 1998-2018. Data on alcohol, diet, activity, and cognition were collected by questionnaire and cognitive levels were judged by the Mini-Mental State Examination scale (also referenced to the Functional Assessment Staging Test). Data cleaning and preprocessing was implemented by R software. The dynamic Cox model was applied for model construction and data analysis.
RESULTS: The results of the dynamic Cox model suggested that seniors who drank alcohol were at higher risk of cognitive decline compared to those who never drank (HR = 1.291, 95%CI: 1.175-1.419). The risk was similarly exacerbated by perennial drinking habits (i.e., longer drinking years, HR = 1.008, 95%CI: 1.004-1.013). Compared to non-alcoholic beverages, liquor (>/= 38 degrees ), liquor (< 38 degrees ), wine and rice wine all showed negative effects. Whereas, the risk of cognitive decline was relatively lower in seniors who consumed liquors (< 38 degrees ) and rice wine compared to the high-level liquor (HR: 0.672 (0.508, 0.887) and 0.732 (0.559, 0.957), respectively).
CONCLUSIONS: Alcohol consumption has a negative and long-term effects on cognitive function in seniors. For the elderly, we suggested that alcohol intake should be avoided as much as possible.
PURPOSE: The association between alcohol intake and glioma remains unclear. We evaluated the association between alcohol intake and incidence of glioma in three large, prospective cohort studies with repeated alcohol assessments.
METHODS: We harnessed data from three studies with repeat alcohol assessment to compute hazard ratios (HR) and 95% confidence intervals (CI) for glioma by overall alcohol intake and intake from specific beverages using Cox proportional hazards regression, adjusted for age, cohort, body mass index, smoking status, and caloric intake. Analyses were conducted separately for glioma overall and for glioblastoma (GBM).
RESULTS: We confirmed 554 incident glioma cases (362 GBM) among 237,505 participants with 6,216,378 person-years of follow up. Cumulative average alcohol intake was associated with reduced risk of glioma (HR = 0.75, 95%CI:0.56-0.99 comparing > 8-15 to 15 g/d to </= 0.5 g/d). When stratified by sex, for the same comparisons, the HRs for men were 0.57 (95%CI:0.36-0.89) and 0.79 (0.53-1.16), and for women 0.90 (95%CI:0.62-1.30) and 0.62, 95%CI:0.39-0.97. Results were consistent when examining cumulative average, baseline, and recent intake, and with a 4 year lag.
CONCLUSION: These results provide evidence against a positive association between alcohol intake and glioma risk. Alcohol intake was associated with reduced risk of glioma in both men and women.