Alcohol consumption and risk of unemployment, sickness absence and disability pension in Denmark: a prospective cohort study

AIMS

We investigated the association between weekly alcohol consumption and binge drinking and the risk of unemployment, sickness absence and disability pension.

DESIGN

Prospective register-based cohort study.

SETTING

Denmark.

PARTICIPANTS

A sample of 17 690 men and women, aged 18-60 years from the Danish Health and Morbidity Survey in 2000, 2005 and 2010 participated in the study. Participants worked the entire year prior to baseline.

MEASUREMENTS

Administrative registers were used to obtain information on unemployment, sickness absence and disability pension during a 5-year follow-up period. Data were analysed by multivariate Cox regression model with random effect (frailty) adjusted for cohabitation status, educational level, Charlson comorbidity index, smoking habits, calendar year and geographic region.

FINDINGS

Among males, adjusted hazards ratios (HR) of unemployment were 1.24 (95% CI 1.05-1.46, P = 0.01), 1.28 (95% CI 1.04-1.59, P =0.02) and 1.48 (95% CI 1.21-1.81, P = 0.00) respectively, for abstainers and those with alcohol consumption of 21-27 and ≥ 28 drinks per week when compared with individuals who had 1-13 drinks per week. Corresponding HRs for sickness absence were 1.16 (95% CI 1.02-1.33, P = 0.03), 1.02 (95% CI 0.85-1.23, P = 0.84), and 1.23 (95 % CI 1.04-1.46, P = 0.02). Male abstainers had increased HR for subsequently receiving disability pension. Female abstainers had increased HR of unemployment, sickness absence and disability pension compared to women with moderate alcohol consumption. Binge drinking was associated with higher HR of unemployment compared to non-binge drinking in women: HR of 1.21 (95 % CI 1.03-1.41, P = 0.02).

CONCLUSIONS

In Danish men aged 18-60, alcohol abstinence and heavy consumption is associated with increased subsequent risk of unemployment and sickness absence compared with low consumption. In Danish women abstainers have increased risk of unemployment, sickness absence and disability pension, while binge drinkers are more likely to become unemployed subsequently.

Alcohol Use and Breast Cancer: A Critical Review

The objective of this study was to outline the biological pathways of alcohol-attributable breast cancer, the epidemiological risk relationship between alcohol consumption and breast cancer, and the global burden of breast cancer incidence and mortality attributable to alcohol consumption, with a focus on light drinking. First, the literature regarding the biological mechanisms of how alcohol affects the risk of breast cancer was reviewed and summarized. Second, a search of meta-analyses that evaluated the risk relationship between alcohol consumption and breast cancer was conducted. Last, the burden of alcohol-attributable breast cancer incidence and mortality was estimated by means of a Population-Attributable Fraction methodology. Data on alcohol consumption were obtained from the Global Information System on Alcohol and Health, and data on cancer incidence and mortality were obtained from the GLOBOCAN database. Alcohol consumption affects breast cancer risk through the alteration in hormone levels and the associated biological pathways, the metabolism of ethanol resulting in carcinogens, and the inhibition of the one carbon metabolism pathway. The systematic review found 15 meta-analyses on the risk relationship between alcohol consumption (also light consumption) and the risk of breast cancer. All but 2 of these analyses showed a dose-response relationship between alcohol consumption and the risk of breast cancer. An estimated 144,000 (95% confidence interval [CI]: 88,000 to 200,000) breast cancer cases and 38,000 (95% CI: 2,400 to 53,000) breast cancer deaths globally in 2012 were attributable to alcohol, with 18.8% of these cases and 17.5% of these deaths affecting women who were light alcohol consumers. All levels of evidence showed a risk relationship between alcohol consumption and the risk of breast cancer, even at low levels of consumption. Due to this strong relationship, and to the amount of alcohol consumed globally, the incidence of and mortality from alcohol-attributable breast cancer is large.

Five year change in alcohol intake and risk of breast cancer and coronary heart disease among postmenopausal women: prospective cohort study

OBJECTIVE

To test the hypothesis that postmenopausal women who increase their alcohol intake over a five year period have a higher risk of breast cancer and a lower risk of coronary heart disease compared with stable alcohol intake.

DESIGN

Prospective cohort study.

SETTING

Denmark, 1993-2012.

PARTICIPANTS

21 523 postmenopausal women who participated in the Diet, Cancer, and Health Study in two consecutive examinations in 1993-98 and 1999-2003. Information on alcohol intake was obtained from questionnaires completed by participants.

MAIN OUTCOME MEASURES

Incidence of breast cancer, coronary heart disease, and all cause mortality during 11 years of follow-up. Information was obtained from the Danish Cancer Register, Danish Hospital Discharge Register, Danish Register of Causes of Death, and National Central Person Register. We estimated hazard ratios according to five year change in alcohol intake using Cox proportional hazards models.

RESULTS

During the study, 1054, 1750, and 2080 cases of breast cancer, coronary heart disease, and mortality occurred, respectively. Analyses modelling five year change in alcohol intake with cubic splines showed that women who increased their alcohol intake over the five year period had a higher risk of breast cancer and a lower risk of coronary heart disease than women with a stable alcohol intake. For instance, women who increased their alcohol intake by seven or 14 drinks per week (corresponding to one or two drinks more per day) had hazard ratios of breast cancer of 1.13 (95% confidence interval 1.03 to 1.23) and 1.29 (1.07 to 1.55), respectively, compared to women with stable intake, and adjusted for age, education, body mass index, smoking, Mediterranean diet score, parity, number of births, and hormone replacement therapy. For coronary heart disease, corresponding hazard ratios were 0.89 (0.81 to 0.97) and 0.78 (0.64 to 0.95), respectively, adjusted for age, education, body mass index, Mediterranean diet score, smoking, physical activity, hypertension, elevated cholesterol, and diabetes. Results among women who reduced their alcohol intake over the five year period were not significantly associated with risk of breast cancer or coronary heart disease. Analyses of all cause mortality showed that women who increased their alcohol intake from a high intake (≥14 drinks per week) to an even higher intake had a higher mortality risk that women with a stable high intake.

CONCLUSION

In this study of postmenopausal women over a five year period, results support the hypotheses that alcohol intake is associated with increased risk of breast cancer and decreased risk of coronary heart disease.

Female breast cancer and alcohol consumption: a review of the literature

CONTEXT

Consumption of alcoholic beverages is one of the single most important known and modifiable risk factor for human cancer. Among women, breast cancer is the most common cancer worldwide and the leading cause of cancer-related mortality. Consumption of alcoholic beverages is causally associated with female breast cancer and the association shows a linear dose-response relationship. The role of heavy drinking has been long recognized and even a moderate intake is associated with an increased risk for breast cancer. The present review is an update of the current evidence on the association between alcohol consumption and breast cancer risk. The aim is to gain further insight into this association and to improve our current understanding of the effects of the major modifying factors.

EVIDENCE ACQUISITION

Epidemiologic and experimental studies published since the most recent International Agency for Research on Cancer (IARC) Monograph on alcoholic beverages were identified in PubMed using a combination of keywords such as alcohol, breast cancer, polymorphisms, menopausal status.

EVIDENCE SYNTHESIS

Cumulative lifetime consumption, drinking frequency, drinking patterns and timing of exposure each modulate the association between alcohol consumption and breast cancer. Hormonal status, genetic polymorphisms, and nutritional factors may interact with ethanol metabolism and further influence breast cancer risk.

CONCLUSIONS

Better standardization among experimental and epidemiologic designs in assessing alcohol intake and timing of exposure may improve our understanding of the heterogeneity observed across studies, possibly allowing the quantification of the effects of occasional heavy drinking and the identification of a window of higher susceptibility to breast cancer development.

Dual association between polyphenol intake and breast cancer risk according to alcohol consumption level: a prospective cohort study

Studies of the association between polyphenols dietary intake and breast cancer risk have been limited due to the lack of detailed food composition tables. In addition, none has examined this association according to alcohol intake, despite the facts that alcohol is an established risk factor for breast cancer and that the contribution of alcoholic beverages to polyphenol intake varies according to the level of alcohol consumption. Our objectives were (1) to estimate the associations between breast cancer risk and a wide range of dietary polyphenols using the recently published Phenol-Explorer database; and (2) to evaluate if/how alcohol intake modulates these relationships. 4,141 women from the SU.VI.MAX prospective cohort were followed from 1994 to 2007 (median followup: 12.6 years); 152 developed a first incident invasive primary breast cancer. Dietary intakes were assessed by repeated 24-h records. The Phenol-Explorer database was used to estimate polyphenol intake. Multivariable Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95 % confidence intervals (CIs) for quartiles of polyphenol intake. Analyses were stratified by median alcohol intake (< vs. ≥ 6.5 g/d). In non-to-low alcohol drinkers, intakes of some classes of polyphenols were associated with decreased breast cancer risk: hydroxybenzoic acids (HR(Q4vsQ1) = 0.38, 95 % CI: 0.17-0.86, P (trend) = 0.005), flavonoids (0.35, 0.17-0.75, P (trend) = 0.02), flavonols (0.36, 0.18-0.74, P (trend) = 0.002), catechins (0.48, 0.22-1.05, P (trend) = 0.02), theaflavins (0.42, 0.19-0.93, P (trend) = 0.02), and proanthocyanidins (0.39, 0.18-0.84, P (trend) = 0.02). In contrast, in women with higher alcohol use, intakes of hydroxybenzoic acids (2.28, 1.16-4.49, P (trend) = 0.04), flavonoids (2.46, 1.23-4.92, P (trend) = 0.01), anthocyanins (2.94, 1.32-6.53, P (trend) = 0.01), catechins (2.28, 1.19-4.36, P (trend) = 0.02), and proanthocyanidins (2.98, 1.40-6.33, P (trend) = 0.006) were associated with increased breast cancer risk. In conclusion, this prospective study suggests that several classes of polyphenols could potentially contribute to breast cancer prevention among non-to-low alcohol drinkers, but some may increase breast cancer risk among women with higher alcohol intake.

Improving the power of chronic disease surveillance by incorporating residential history

We present a global test for disease clustering with power to identify disturbances from the null population distribution which accounts for the lag time between the date of exposure and the date of diagnosis. Location at diagnosis is often used as a surrogate for the location of exposure; however, the causative exposure could have occurred at a previous address in a case's residential history. We incorporate models for the incubation distribution of a disease to weight each address into the residential history by the corresponding probability of the exposure occurring at that address. We then introduce a test statistic which uses these incubation-weighted addresses to test for a difference between the spatial distribution of the cases and the spatial distribution of the controls, or the background population. We follow the construction of the M statistic to evaluate the significance of these new distance distributions. Our results show that gains in detection power when residential history is accounted for are of such a degree that it might make the qualitative difference between the presence of spatial clustering being detected or not, thus making a strong argument for the inclusion of residential history in the analysis of such data.

Alcohol and folate intake and breast cancer risk in the WHI Observational Study

BACKGROUND

Alcohol increases breast cancer risk. Epidemiological studies suggest folate may modify this relationship.

OBJECTIVE

To examine the relationship among breast cancer, alcohol and folate in the Women's Health Initiative-Observational Study (WHI-OS).

METHODS

88,530 postmenopausal women 50-79 years completed baseline questionnaires between October 1993 and December 1998, which addressed alcohol and folate intake and breast cancer risk factors. Cox proportional hazards analysis examined the relationship between self-reported baseline alcohol and folate intake and incident breast cancer.

RESULTS

1,783 breast cancer cases occurred over 5 years. Alcohol was associated with increased risk of breast cancer (RR = 1.005, 95%CI 1.001-1.009). Risk increased with consumption of alcohol (up to 5 g/d, adjusted HR = 1.10, 95%CI 0.96-1.32; >5-15 g/d HR = 1.14, 95%CI 0.99-1.31; and >15 g/d HR = 1.13 95%CI 0.96-1.32). We found no significant interaction between alcohol and folate in our adjusted model.

CONCLUSIONS

We found no evidence for folate attenuating alcohol's effect on breast cancer risk in postmenopausal women. Our results may be due to misclassification of folate intake or the relatively short follow-up period.