It should be noted that the subjects of this cohort are drawn from the general population of the community, but the study area is limited to Suzhou City. It would be prudent to exercise caution when extrapolating the findings to the broader Chinese population. A set of covariates available in all NHIS surveys was included as confounders to estimate alcohol consumption. Demographic characteristics included age, sex, race/ethnicity, education, and marital status. Lifestyle factors included body mass index, physical activity, and smoking status. Chronic health conditions included cancer, diabetes mellitus, heart disease, hypertension, stroke, asthma, emphysema, and chronic bronchitis.
The interaction between smoking and alcohol consumption was in a direction opposite to the independent effects of alcohol and smoking, suggesting a protective effect of alcohol with heavier amounts of smoking. Additional study is needed to further assess the relationship between respiratory symptoms and alcohol consumption, and between pulmonary function and alcohol consumption. Capturing accurate clinical information about alcohol behavior, particularly for those with large intake, is challenging and study participants may have misreported alcohol intake. Self-reporting of alcohol intake, as in the National Health and Nutrition Examination Survey (NHANES) alcohol questionnaire, has been validated by surrogate reporting and by biomarker studies. Therefore, self-report is generally accepted as a valid and reasonably accurate way to quantify alcohol intake for population research studies.30 The retrospective nature of the alcohol intake questionnaire is also subject to recall bias.
We also note that we had a very limited number of heavy alcohol users, so we have limited ability to draw conclusions about that particular group. Recruitment of such subjects is challenging, particularly in the context of a longitudinal trial such as the trial within which the present study was nested. First, we recalculated the estimates by excluding participants who died within the first 2 years (i.e., a 2-year lag). Second, we conducted the analyses by excluding individuals with physician-diagnosed diseases. Third, to examine the effects of missing data, a sensitivity analysis was conducted after multiple imputations for variables with missing values.
Women were asked about education level, weight, height, time per day spent on walking and/or cycling, smoking status, and alcohol consumption. Body Mass Index (BMI) was calculated by dividing the weight in kilograms by the square of the height in meters. Participants reported average number of cigarettes smoked per day at different ages (15–20, 21–30, 31–40, 41–50, 51–60 years old, and in the year of data collection), and indicated when they started and stopped smoking (only if this event occurred). Pack-years of smoking were calculated by multiplying the number of cigarettes smoked per day by number of years smoked, respectively, for each age category. The cardiovascular effects of acute alcohol exposure remain incompletely understood, despite its reported association with arrhythmias like atrial fibrillation (AF). The Munich-BREW II study supported a link between excessive alcohol consumption, elevated heart rate, impaired heart rate variability (HRV), and increased arrhythmia incidence.
The association between alcohol consumption and risk of COPD exacerbation in a veteran population
- Over the past decades, the rapid economic development in China has contributed to an exacerbation of the gap between the rich and the poor, which has in turn exacerbated health inequalities 32, 33.
- Finally, the NHIS Linked Mortality File identified causes of death information by linkage to the NDI, which is derived from death certificates.
- All-cause mortality according to alcohol consumptionstatus and NHIS year among NHIS participants in 1997 to2014.Hazards ratios for all-cause and cause-specific mortality according to alcoholconsumption status among NHIS participants in 1997 to 2014.
- Dietary information was measured by frequency of intakes of fruits, vegetables and red meat.
- Former drinkers in data years 1997 to 2000 were classified as former regular drinkers.
- Chronic health conditions included cancer, diabetes mellitus, heart disease, hypertension, stroke, asthma, emphysema, and chronic bronchitis.
EEW conceived and designed the study, directed the statistical analyses, interpreted the data, drafted the manuscript, and approved the final version. DEN and KMK assisted in conception and design of the study, directed the statistical analyses, interpreted the data, revised the manuscript critically for important intellectual content, and approved the final version. JHS contributed to interpretation of the data, revised the manuscript critically for important intellectual content, and approved the final version. SL and JEC performed the statistical analyses, contributed to interpretation of the data, revised the manuscript critically for important intellectual content, and approved the final alcohol consumption and risk of chronic obstructive pulmonary disease: a prospective cohort study of men version. EEW and KMK had full access to the data and take responsibility for the integrity of the data and the accuracy of the data analyses. The strengths of our current study include its large size, use of spirometry to confirm COPD, and its careful collection of prospective AECOPD data, which was the primary outcome of the main trial.
Study design and participants
In China, the dearth of hygienic domestic fuels and inadequate kitchen ventilation may contribute to indoor air pollution, which has been identified as a threat to women with COPD 26. Forum members thought that there are a number of deficiencies in this study that somewhat weaken its conclusions; especially important was the lack of ability to consider the pattern of drinking (regular, moderate versus binge drinking). Still, there is a strong consistency between the results of this study (indicating a “J-shaped” or “U-shaped” curve for alcohol intake and COPD) and results from extensive previous epidemiologic and experimental research.
Long-term dietary fiber intake and risk of chronic obstructive pulmonary disease: a prospective cohort study of women
- The results did not differ with a HR of 0.70 (95% CI 0.59–0.82) comparing women in the highest vs. the lowest total dietary fiber intake.
- Combined relative risks (RRs) and 95% confidence intervals (CIs) were calculated with the random effects model (REM).
- The possible beneficial and detrimental effects of alcohol consumption, as investigated in many studies, have been hotly debated 1, 2.
- The CKB study was approved by the Ethical Review Committee of the Chinese Center for Disease Control and Prevention and the Oxford Tropical Research Ethics Committee, University of Oxford.
Of the 1,082 subjects, 645 participants (59.6%) reported minimal to no alcohol intake, 363 (33.5%) reported light-to-moderate intake, and 74 (6.8%) reported heavy intake. Little is known about the effects of alcohol consumption on susceptibility to AECOPD. Using previously collected data from a large randomized controlled trial of patients with COPD, we performed a secondary analysis to evaluate the relationship between alcohol consumption and the risk of AECOPD.
Risk of COPD development based on smoking status
Finally, the NHIS Linked Mortality File identified causes of death information by linkage to the NDI, which is derived from death certificates. Although this methodology has been previously validated by many published reports, the possibility of cause-of-death misclassification cannot be ruled out. Participants contributed person-years in this analysis from enrollment into the baseline study to occurrence of the endpoint event of COPD, death, loss to follow-up or 31 December 2017, whichever occurred first. Cox proportional hazard regression models were used to estimate the association between SES and the risk of incidence of COPD by calculating hazard ratios (HR) and 95% confidence intervals (CI). Model 2 additionally included education, marital status, physical activity, BMI, alcohol consumption, frequency of red meat, frequency of fruits or vegetables, prevalent respiratory disease at baseline, and smoking status. Model 3 further adjusted passive smoking, cooking fuel pollution, and heating fuel pollution.
Study participants
Rate of AECOPD was determined by dividing the number of AECOPDs by person-years of follow-up, allowing use of data from patients with multiple exacerbations during follow-up. The relationship between alcohol consumption and rate of AECOPD was analyzed using zero-inflated negative binomial regression. Summary risk estimates of COPD for fruit and vegetable intake by study characteristics. This meta-analysis indicates that fruit and vegetable intake might be related to a lower risk of COPD. The potential mechanism may be that SES is related to the extent to which individuals are able to access health resources, including health knowledge, health behaviors, and healthcare services 23, 24.
Our data thus suggest that it is primarily the acute degree of drunkenness, measured by BAC, that mirrors the acute cardiac effects of alcohol consumption. The individual BAC level needs to be reached individually, and the amount of alcohol required to reach this BAC depends on many factors including sex and BMI. Other factors, unmeasured in our current study, may further include the level of physical fitness or individual blood pressure, liver function, and concomitant food intake 10,11,12 as well as how blood alcohol levels correlated to BAC levels.
4. Data Extraction
A likelihood ratio test was used to examine the interaction between long-term fiber intake and smoking status (ever vs. ex-smokers vs. current smokers) on COPD risk. The shape of the association between risk of COPD and long-term total dietary fiber intake was investigated using restricted cubic-splines with three knots (at the 10th, 50th, 90th percentile) 25. (SAS Institute Inc, Cary, NC, USA) and STATA v. 13 (StataCorp, College Station, TX, USA). All P values were two-sided and values ≤ 0.05 were considered statistically significant. Data about food consumption were collected by food frequency questionnaires (FFQs) based on 67 food items in 1987 and 96 food items in 1997. Participants were asked about their average food consumption during the past year based on eight predefined frequency categories, ranging from “never/seldom” to “4 times per day” in 1987, and from “0 times per month” to “3 + times per day” in 1997.
The opinions expressed in all articles published here are those of the specific author(s), and do not necessarily reflect the views of Dove Medical Press Ltd or any of its employees. Univariate analysis of continuous and categorical data utilized Student’s t-tests and chi-square tests, respectively. Each participating institution’s institutional review board approved the protocol.
