A Large Cohort Study of Body Mass Index and Pancreatic Cancer by Smoking Status

Plant-based diets and the risk of pancreatic cancer: a large prospective multicenter study

BACKGROUND

Plant-based diets have been recommended for improving health outcomes, including cancer. However, previous studies on plant-based diets and the risk of pancreatic cancer are scarce and fail to consider plant food quality.

OBJECTIVES

We sought to examine the potential associations of 3 plant-based diet indices (PDIs) with the risk of pancreatic cancer in a US population.

METHODS

A population-based cohort of 101,748 US adults was identified from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. The overall PDI, healthful PDI (hPDI), and unhealthful PDI (uPDI) were constructed to qualify adherence to overall, healthy, and less healthy plant-based diets, respectively, with higher scores indicating better adherence. Multivariable Cox regression was used to compute hazard ratios (HRs) for pancreatic cancer incidence. Subgroup analysis was conducted to identify the potential effect modifiers.

RESULTS

Over a mean follow-up of 8.86 years, 421 pancreatic cancer cases occurred. Participants in the highest compared with the lowest quartiles of overall PDI had a lower risk of pancreatic cancer [HR_{quartile 4 versus 1}: 0.74; 95% confidence interval (CI): 0.57, 0.96; P_trend = 0.023]. A stronger inverse association was observed for hPDI (HR_{quartile 4 versus 1}: 0.56; 95% CI: 0.42, 0.75; P_trend < 0.001). Conversely, uPDI was positively associated with the risk of pancreatic cancer (HR_{quartile 4 versus 1}: 1.38; 95% CI: 1.02, 1.85; P_trend = 0.012). Subgroup analyses revealed a stronger positive association for uPDI in participants with BMI <25 (HR_{quartile 4 versus 1}: 3.22; 95% CI: 1.56, 6.65) than in those with BMI ≥25 (HR_{quartile 4 versus 1}: 1.08; 95% CI: 0.78, 1.51) (P_interaction = 0.001).

CONCLUSIONS

In this US population, adherence to a healthy plant-based diet confers a lower risk of pancreatic cancer, whereas adherence to a less healthy plant-based diet confers a higher risk. These findings highlight the importance of considering plant food quality in preventing pancreatic cancer.

Alcohol consumption and incidence of pancreatic cancer

Purpose

The association between alcohol consumption and pancreatic cancer is unsettled.

Methods

Altogether 243,169 men and women 20-79 years, without cancer at baseline, were followed with respect to pancreatic cancer by linkage to the Cancer Registry of Norway and the Norwegian Cause of Death Registry. They participated in a cardiovascular survey where information on alcohol consumption, smoking habits, anthropometric measures, and some biological variables were recorded. During 20 years of follow-up, 991 incident pancreatic cancers were registered. We estimated the hazard ratios with the Cox proportional hazards model, and graphed spline curves between glass-units/d of alcohol and hazard ratio of incident pancreatic cancer.

Results

The multivariable adjusted hazard per 1 glass-unit/d was 1.08 (95% confidence interval 1.02-1.15) for men and 1.04 (0.97-1.13) for women. The association between alcohol consumption and incident pancreatic cancer was present in ex- and current smokers, but the association could be ascribed to smoking habits. The multivariable adjusted spline curves increased with increasing glass-units/d and with confidence bands not encompassing 1.0 above one glass-unit/day.

Conclusion

Our findings of an association between higher level of alcohol consumption and incident pancreatic cancer, could be attributed to confounding by smoking habits.

Coffee consumption and breast cancer risk: a narrative review in the general population and in different subtypes of breast cancer

PURPOSE

Most of the existing literature reports no association or a slight negative association between coffee consumption and the risk of developing breast cancer. However, the level of risk differs when considering various subgroups, such as menopausal status, hormonal status of the tumor or genetic mutations. The present review based on a literature search sets the point on the potential influence of a common daily drink, coffee, on the risk of developing breast cancer in the general population, in different subgroups of women and the consequences of drinking coffee after breast cancer has been diagnosed and treated.

RESULTS

This review confirms that in the general population, there is no association between coffee intake and breast cancer risk or a slight protective effect, even at high dosages. Coffee is inversely associated with breast cancer risk in postmenopausal women and in women carrying a BRCA1 mutation. Possible risk differences exist between slow and fast caffeine metabolizers and with weight. Coffee consumption after breast cancer diagnosis and surgery, associated with tamoxifen and/or radiotherapy, reduced the occurrence of early events. The effects of coffee intake are less clear in other subgroups, mainly premenopausal women, women carrying a BRCA2 mutation and tumors with variable hormonal status (positive or negative for ER/PR) and would need additional studies.