Coffee consumption and the risk of overall and fatal prostate cancer in the NIH-AARP Diet and Health Study

Association between Coffee Consumption and Risk of Prostate Cancer in Japanese Men: A Population-Based Cohort Study in Japan

BACKGROUND

Although numerous epidemiological studies have examined whether coffee consumption is associated with prostate cancer risk, the results remain controversial. Moreover, there are few studies in Asian populations. Therefore, we investigated the association between coffee consumption and the risk of prostate cancer in a large-scale prospective population-based cohort study in Japan.

METHODS

Study subjects were 48,222 men (40-69 years) who completed a questionnaire that included questions about their coffee consumption in 1990 for Cohort I and 1993 for Cohort II and were followed up until December 31, 2015. Newly diagnosed cases were classified into localized and advanced using information on local staging, the Gleason score, and degree of differentiation. Hazard ratios (HR) and 95% confidential intervals (95% CI) were estimated using Cox regression analysis.

RESULTS

A total of 1,617 participants were newly diagnosed with prostate cancer during a mean follow-up period of 18.8 years. Of these, 1,099 and 461 patients had localized and advanced cancer, respectively. There was no association between coffee intake and prostate cancer risk. Comparison between the highest and lowest category of coffee consumption produced HRs of 1.08 (95% CI, 0.90-1.30), 1.08 (95% CI, 0.84-1.38), and 1.00 (95% CI, 0.67-1.47) for risk of total, localized, and advanced cancer, respectively. The same results were obtained even when we limited the analysis to patients with subjective symptoms.

CONCLUSIONS

Our findings suggest that coffee consumption has no impact on prostate cancer risk in Japanese men.

IMPACT

Coffee has no protective effects against prostate cancer among Japanese men.

Coffee consumption and risk of prostate cancer: a systematic review and meta-analysis

OBJECTIVES

To conduct a systematic review with meta-analysis of cohort studies to evaluate the association of coffee consumption with the risk of prostate cancer.

DATA SOURCES

PubMed, Web of Science and Embase were searched for eligible studies up to September 2020.

STUDY SELECTION

Cohort studies were included.

DATA EXTRACTION AND SYNTHESIS

Two researchers independently reviewed the studies and extracted the data. Data synthesis was performed via systematic review and meta-analysis of eligible cohort studies. Meta-analysis was performed with the "metan" and "glst" commands in Stata 14.0.

MAIN OUTCOMES AND MEASURES

Prostate cancer was the main outcome. It was classified as localised prostate cancer which included localised or non-aggressive cancers; advanced prostate cancer which included advanced or aggressive cancers; or fatal prostate cancer which included fatal/lethal cancers or prostate cancer-specific deaths.

RESULTS

Sixteen prospective cohort studies were finally included, with 57 732 cases of prostate cancer and 1 081 586 total cohort members. Higher coffee consumption was significantly associated with a lower risk of prostate cancer. Compared with the lowest category of coffee consumption, the pooled relative risk (RR) was 0.91 (95% CI 0.84 to 0.98), I²= 53.2%) for the highest category of coffee consumption. There was a significant linear trend for the association (p=0.006 for linear trend), with a pooled RR of 0.988 (95% CI 0.981 to 0.995) for each increment of one cup of coffee per day. For localised, advanced and fatal prostate cancer, the pooled RRs were 0.93 (95% CI 0.87 to 0.99), 0.88 (95% CI 0.71 to 1.09) and 0.84 (95% CI 0.66 to 1.08), respectively. No evidence of publication bias was indicated in this meta-analysis.

CONCLUSIONS

This study suggests that a higher intake of coffee may be associated with a lower risk of prostate cancer.

Bioactive compounds, antioxidant activity and antiproliferative effects in prostate cancer cells of green and roasted coffee extracts obtained by microwave-assisted extraction (MAE)

Coffee consumption has been investigated as a protective factor against prostate cancer. Coffee may be related to prostate cancer risk reduction due to its phytochemical compounds, such as caffeine, chlorogenic acids, and trigonelline. The roasting process affects the content of the phytochemicals and undesired compounds can be formed. Microwave-assisted extraction is an alternative to conventional extraction techniques since it preserves more bioactive compounds. Therefore, this study aimed to evaluate the phytochemical composition and the putative preventive effects in prostate cancer development of coffee beans submitted to four different coffee-roasting degrees extracted using microwave-assisted extraction. Coffea arabica green beans (1) were roasted into light (2), medium (3) and dark (4) and these four coffee samples were submitted to microwave-assisted extraction. The antioxidant capacity of these samples was evaluated by five different methods. Caffeine, chlorogenic acid and caffeic acid were measured through HPLC. Samples were tested against PC-3 and DU-145 metastatic prostate cancer cell lines regarding their effects on cell viability, cell cycle progression and apoptotic cell death. We found that green and light roasted coffee extracts had the highest antioxidant activity. Caffeine content was not affected by roasting, chlorogenic acid was degraded due to the temperature, and caffeic acid increased in light roasted and decreased in medium and dark roasted. Green and light roasted coffee extracts promoted higher inhibition of cell viability, caused greater cell cycle arrest in S and G₂/M and induced apoptosis more compared to medium and dark roasted coffee extracts and the control samples. Coffee extracts were more effective against DU-145 than in PC-3 cells. Our data provide initial evidence that among the four tested samples, the consumption of green and light coffee extracts contributes to inhibit prostate cancer tumor progression features, potentially preventing aspects related to advanced prostate cancer subtypes.

Coffee and tea consumption and risk of prostate cancer in the European Prospective Investigation into Cancer and Nutrition

The epidemiological evidence regarding the association of coffee and tea consumption with prostate cancer risk is inconclusive, and few cohort studies have assessed these associations by disease stage and grade. We examined the associations of coffee (total, caffeinated and decaffeinated) and tea intake with prostate cancer risk in the European Prospective Investigation into Cancer and Nutrition. Among 142,196 men, 7,036 incident prostate cancer cases were diagnosed over 14 years of follow-up. Data on coffee and tea consumption were collected through validated country-specific food questionnaires at baseline. We used Cox proportional hazards regression models to compute hazard ratios (HRs) and 95% confidence intervals (CI). Models were stratified by center and age, and adjusted for anthropometric, lifestyle and dietary factors. Median coffee and tea intake were 375 and 106 mL/day, respectively, but large variations existed by country. Comparing the highest (median of 855 mL/day) versus lowest (median of 103 mL/day) consumers of coffee and tea (450 vs. 12 mL/day) the HRs were 1.02 (95% CI, 0.94-1.09) and 0.98 (95% CI, 0.90-1.07) for risk of total prostate cancer and 0.97 (95% CI, 0.79-1.21) and 0.89 (95% CI, 0.70-1.13) for risk of fatal disease, respectively. No evidence of association was seen for consumption of total, caffeinated or decaffeinated coffee or tea and risk of total prostate cancer or cancer by stage, grade or fatality in this large cohort. Further investigations are needed to clarify whether an association exists by different preparations or by concentrations and constituents of these beverages.

Coffee consumption and risk of hypertension: a dose-response meta-analysis of prospective studies

PURPOSE

Recently, a large prospective study provided additional information concerning the debated possible association between habitual coffee consumption and risk of hypertension (HPT). Therefore, we updated the state of knowledge on this issue by carrying out a comprehensive new systematic review of the literature and a meta-analysis of the available relevant studies.

METHODS

We performed a systematic search for prospective studies on general population, published without language restrictions (1966-August 2017). A random-effects dose-response meta-analysis was conducted to combine study specific relative risks (RRs) and 95% confidence intervals. Potential non-linear relation was investigated using restricted cubic splines.

RESULTS

Four studies (196,256 participants, 41,184 diagnosis of HPT) met the inclusion criteria. Coffee intake was assessed by dietary questionnaire. Dose-response meta-analysis showed a non-linear relationship between coffee consumption and risk of HPT (p for non-linearity < 0.001). Whereas the habitual drinking of one or two cups of coffee per day, compared with non-drinking, was not associated with risk of HPT, a significantly protective effect of coffee consumption was found starting from the consumption of three cups of coffee per day (RR = 0.97, 95% CI = 0.94 to 0.99), and was confirmed for greater consumption.

CONCLUSIONS

The results of this analysis indicate that habitual moderate coffee intake is not associated with higher risk of HPT in the general population and that in fact a non-linear inverse dose-response relationship occurs between coffee consumption and risk of HPT.

Investigating the possible causal role of coffee consumption with prostate cancer risk and progression using Mendelian randomization analysis

Coffee consumption has been shown in some studies to be associated with lower risk of prostate cancer. However, it is unclear if this association is causal or due to confounding or reverse causality. We conducted a Mendelian randomisation analysis to investigate the causal effects of coffee consumption on prostate cancer risk and progression. We used two genetic variants robustly associated with caffeine intake (rs4410790 and rs2472297) as proxies for coffee consumption in a sample of 46,687 men of European ancestry from 25 studies in the PRACTICAL consortium. Associations between genetic variants and prostate cancer case status, stage and grade were assessed by logistic regression and with all-cause and prostate cancer-specific mortality using Cox proportional hazards regression. There was no clear evidence that a genetic risk score combining rs4410790 and rs2472297 was associated with prostate cancer risk (OR per additional coffee increasing allele: 1.01, 95% CI: 0.98,1.03) or having high-grade compared to low-grade disease (OR: 1.01, 95% CI: 0.97,1.04). There was some evidence that the genetic risk score was associated with higher odds of having nonlocalised compared to localised stage disease (OR: 1.03, 95% CI: 1.01, 1.06). Amongst men with prostate cancer, there was no clear association between the genetic risk score and all-cause mortality (HR: 1.00, 95% CI: 0.97,1.04) or prostate cancer-specific mortality (HR: 1.03, 95% CI: 0.98,1.08). These results, which should have less bias from confounding than observational estimates, are not consistent with a substantial effect of coffee consumption on reducing prostate cancer incidence or progression.

Coffee and cancer risk: A meta-analysis of prospective observational studies

Meta-analyses on coffee and cancer incidence mainly restricted to limited cancers. We carried out a more comprehensive meta-analysis of cohort studies to explore association between coffee and most cancer types. We conducted comprehensive search and summarized relative risk (RR) and 95% confidence intervals for the highest versus lowest coffee intake and cancer using STATA12. We conducted dose-analysis if result suggested significant association. The publication bias was evaluated with begg's and egger's test. Finally, 105 individual prospective studies were included. Inverse associations were observed on oral, pharyngeal, colon, liver, prostate, endometrial cancer and melanoma, with RR 0.69 (95% CI = 0.48-0.99, I² = 73.4%, P = 0.044), 0.87 (95% CI = 0.78-0.96, I² = 28.4%, P = 0.007), 0.46 (95% CI = 0.37-0.57, I² = 0%, P = 0), 0.89 (95% CI = 0.84-0.93, I² = 30.3%, P = 0.003), 0.73 (95% CI = 0.67-0.80, I²  = 0%, P = 0) and 0.89 (95% CI = 0.80-0.99, I²  = 0%, P = 0.031) respectively. However, the relative risk for lung cancer is 2.18 (95% CI = 1.26-3.75, I²  = 63.3%, P = 0.005). The summary relative risk for increment of 2 cups of coffee were RR = 0.73, 95% CI = 0.67-0.79 for liver cancer, RR = 0.97, 95% CI = 0.96-0.98 for prostate cancer and RR = 0.88, 95% CI = 0.85-0.92 for endometrial cancer. Accordingly, coffee intake was associated with reduced risk of oral, pharynx, liver, colon, prostate, endometrial cancer and melanoma and increased lung cancer risk.

Coffee and the Risk of Lymphoma: A Meta-analysis Article

BACKGROUND

Coffee is implicated in the susceptibility to several cancers. However, the association between coffee and lymphoma remains unclear. This meta-analysis aimed to assess quantitatively the association between coffee and the incidence of lymphoma.

METHODS

A literature search was performed for cohort and case-control studies published using PubMed, Cochrane, and EMBASE databases. Studies were included if they reported relative ratios (RR) and corresponding 95% confidence intervals (CIs) of lymphoma with respect to coffee consumption. Pooled relative risk (RR) and its 95% confidence interval (CI) were calculated. All P values are two tailed.

RESULTS

Seven studies met the inclusion criteria, which included three cohort and four case-control studies. Compared with did not or seldom drink coffee per day, being no significantly association between coffee and risk of lymphoma (pooled RR: 1.05, 95%CI: 0.89-1.23). In the subgroup analysis, no significant association between coffee and lymphoma risk was detected not only in different study types (cohort studies RR: 1.29; 95% CI, 0.92-1.80; case control studies RR: 0.99; 95% CI, 0.82-1.99) but also in different regions (Europe RR: 1.21; 95% CI: 0.99-1.47; USA RR: 0.85; 95% CI, 0.62-1.15; Asia RR: 1.08, 95% CI: 0.84-1.40) and coffee consumption status (≥4cups/d 1.03, 95% CI: 0.69-1.56; < 4cups/d RR: 1.06, 95% CI: 0.89-1.26). The funnel plot revealed no evidence for publication bias.

CONCLUSION

There was no sufficient evidence to support coffee consumption association with the risk of lymphoma. Further well-designed large-scaled cohort studies are needed to provide conclusions that are more definitive.

Coffee consumption and prostate cancer risk: a meta-analysis of cohort studies

This meta-analysis was conducted to assess the association between coffee consumption and prostate cancer risk. Thirteen cohort studies with 34,105 cases and 539,577 participants were included in the meta-analysis. The summary relative risks (RRs) with 95% confidence intervals (CIs) for different coffee intake levels were calculated. Dose-response relationship was assessed using generalized least square trend estimation. The pooled RR for the highest vs. lowest coffee intake was 0.90 (95% CI: 0.85-0.95), with no significant heterogeneity across studies (P = 0.267; I(2) = 17.5%). The dose-response analysis showed a lower cancer risk decreased by 2.5% (RR = 0.975; 95% CI: 0.957-0.995) for every 2 cups/day increment in coffee consumption. Stratifying by geographic region, there was a statistically significant protective influence of coffee on prostate cancer risk among European populations. In subgroup analysis of prostate cancer grade, the summary RRs were 0.89 (95% CI: 0.83-0.96) for nonadvanced, 0.82 (95% CI: 0.61-1.10) for advanced and 0.76 (95% CI: 0.55-1.06) for fatal diseases. Our findings suggest that coffee consumption may be associated with a reduced risk of prostate cancer and it also has an inverse association with nonadvanced prostate cancer. Because of the limited number of studies, more prospective studies with large sample size are needed to confirm this association.

Nutrition, dietary interventions and prostate cancer: the latest evidence

Prostate cancer (PCa) remains a leading cause of mortality in US men and the prevalence continues to rise world-wide especially in countries where men consume a 'Western-style' diet. Epidemiologic, preclinical and clinical studies suggest a potential role for dietary intake on the incidence and progression of PCa. 'This minireview provides an overview of recent published literature with regard to nutrients, dietary factors, dietary patterns and PCa incidence and progression. Low carbohydrates intake, soy protein, omega-3 (w-3) fat, green teas, tomatoes and tomato products and zyflamend showed promise in reducing PCa risk or progression. A higher saturated fat intake and a higher β-carotene status may increase risk. A 'U' shape relationship may exist between folate, vitamin C, vitamin D and calcium with PCa risk. Despite the inconsistent and inconclusive findings, the potential for a role of dietary intake for the prevention and treatment of PCa is promising. The combination of all the beneficial factors for PCa risk reduction in a healthy dietary pattern may be the best dietary advice. This pattern includes rich fruits and vegetables, reduced refined carbohydrates, total and saturated fats, and reduced cooked meats. Further carefully designed prospective trials are warranted.

Boiled coffee consumption and the risk of prostate cancer: follow-up of 224,234 Norwegian men 20-69 years

BACKGROUND

There is insufficient epidemiological evidence on the relationship between type of coffee and the risk of prostate cancer.

METHODS

The risk of prostate cancer by use of boiled vs not boiled coffee were assessed in a prospective study of 224,234 men 20-69 years. 5740 incident prostate cancers were identified.

RESULTS

With no coffee as reference group the hazard ratios of <1-4, 5-8 and 9+ cups per day of boiled coffee only were 0.84 (0.73-0.96), 0.80 (0.70-0.92) and 0.66 (0.55-0.80), P-trend=0.00. The corresponding figures for not boiled coffee were 0.89 (0.80-0.99), 0.91 (0.81-1.02) and 0.86 (0.74-1.00), P-trend=0.22.

CONCLUSION

An inverse relationship between number of cups per day and the risk of prostate cancer was present only for the boiled coffee type.

What should we tell prostate cancer patients about (secondary) prevention?

PURPOSE OF REVIEW

To briefly summarize the epidemiologic findings of selected lifestyle factors for prostate cancer progression, metastasis, or death, with a focus on behaviors after diagnosis where possible. We conclude by providing guidance on the lifestyle practices that physicians may wish to prioritize for discussion with their patients.

RECENT FINDINGS

Growing, but still limited, evidence suggests that lifestyle factors after prostate cancer diagnosis may impact prostate-cancer-specific and overall morality. In particular, smoking and obesity may increase the risk of disease progression and mortality, whereas engaging in vigorous physical activity or brisk walking and consuming a diet rich in vegetables (particularly tomato sauce and cruciferous) and vegetable fats may lower the risk.

SUMMARY

Patients should be counseled not to use tobacco products; to engage in daily physical activity; to minimize sedentary behavior; to consume plenty of healthy fats (i.e. fish, nuts, vegetable oils, soybeans, avocados, and flaxseed) and vegetables; to focus on getting nutrients from foods rather than supplements; and to limit refined grains, sugars, processed meat, and high-fat dairy.

Coffee consumption and urologic cancer risk: a meta-analysis of cohort studies

OBJECTIVES

Controversial results were reported among several epidemiologic studies on the relationship between coffee consumption and urologic cancer risk. We, therefore, conducted this meta-analysis to clarify these associations.

METHODS

Electronic databases including Pubmed, Embase and Cochrane library were searched between January 1966 and August 2013 for eligible studies. Pooled relative risk (RR) and its 95 % confidence interval (CI) were calculated. All P values are two tailed.

RESULTS

Thirteen cohorts were eligible for inclusion. As to prostate cancer (PCa), significant reverse association was found among highest versus none/lowest analysis with acceptable heterogeneity (RR 0.86, 95 % CI 0.79-0.95; I(2) 25 %, P value for heterogeneity: 0.221). A pooled RR which assessed advanced PCa was 0.73 (with 95 % CI 0.50-1.07), and a slight stronger reverse association was found in fatal PCa. However, a slight insignificant reverse association, basing on 8 studies with 9 outcomes, was found in dose-response analysis (RR 0.98, 95 % CI 0.93-1.03). For kidney and bladder cancer, insignificant associations were found in both highest versus none/lowest analyses and dose-response analyses.

CONCLUSIONS

Our findings suggest that coffee consumption may reduce the risk of PCa. No associations were found with both bladder and kidney cancer. Further well-designed large-scaled cohort studies are warranted to provide more definitive conclusions.

Coffee consumption and prostate cancer risk: an updated meta-analysis

PURPOSE

Many epidemiological studies have been conducted to explore the association between coffee consumption and prostate cancer. However, the results remain inconsistent. We performed a large meta-analysis of relevant studies to derive a more precise estimation of this relationship.

METHODS

Systematic searches of PubMed and several other databases up to June 2013 were retrieved. All epidemiologic studies regarding coffee consumption and prostate cancer risk were included, and odds ratios (ORs) with 95 % confidence intervals (CIs) were calculated to estimate the strength of the association.

RESULTS

Twelve case-control studies involving 7,909 prostate cancer cases and 9,461 controls and nine cohort studies involving 455,123 subjects were included in our analysis. Compared with the lowest category, the unstratified highest category of coffee consumption showed a significance reduction in prostate cancer risk of a fixed-effects model (OR 0.91, CI 0.86-0.97). A borderline significant influence was also found when the stratified highest category (US ≥ 4, Europe ≥ 5) of coffee consumption was compared with the reference category (OR 0.96, CI 0.92-1.00), but no relationships were observed for the other two categories. In another analysis conducted by coffee consumption and prostate cancer stage and Gleason grade, our results showed a significant inverse association in all categories of prostate cancer except Gleason <7 grade in a fixed-effects model; the results remained the same, except for advanced prostate cancer, in a random-effects model.

CONCLUSIONS

Our meta-analysis suggests that high (e.g., highest ≥ 4 or 5 cups/day) coffee consumption may not only be associated with a reduced risk of overall prostate cancer, but also inversely associated with fatal and high-grade prostate cancer.

Coffee consumption and risk of nonaggressive, aggressive and fatal prostate cancer--a dose-response meta-analysis

BACKGROUND

Existing epidemiological evidence is controversial regarding the possible associations between coffee consumption and risk of prostate cancer (PCa) by aggressiveness of the disease.

MATERIALS AND METHODS

We conducted a random-effects dose-response meta-analysis to assess the relationships between coffee consumption and nonaggressive, aggressive and fatal PCa risk. Studies were identified by a search of Medline and Embase databases to 15 July 2013. We carried out separate analyses by grade (Gleason score: low-grade, high-grade) and stage (TNM staging system: localized, advanced) of the tumors. Nonaggressive tumors were defined as low-grade or localized, while aggressive tumors were defined as high-grade or advanced.

RESULTS

Eight studies (three case-control and five cohort) were included in this meta-analysis. Gleason 7 tumors were classified as high-grade in one study, while in another study, Gleason 7(4 + 3) tumors were classified as high-grade and Gleason 7(3 + 4) as low-grade. In the remaining four studies, Gleason 7 tumors were excluded from the analyses or analyzed separately. The pooled relative risk (RR) for a consumption increment of 3 cups/day was 0.97 [95% confidence interval (CI) 0.92-1.03] for low-grade PCa (n = 6), 0.97 (95% CI 0.94-0.99) for localized PCa (n = 6), 0.89 (95% CI 0.78-1.00) for high-grade PCa (n = 6), 0.95 (95% CI 0.85-1.06) for advanced PCa (n = 6) and 0.89 (95% CI 0.82-0.97) for fatal PCa (n = 4). No evidence of publication bias was observed. Heterogeneity was absent or marginal (I(2) range = 0-26%), with the only exception of the analysis on advanced PCa, where moderate heterogeneity was observed (I(2) = 60%). When restricting the analyses only to those studies that defined high-grade tumors as Gleason 8-10, the inverse association became slightly stronger [RR: 0.84 (95% CI 0.72-0.98); n = 4].

CONCLUSIONS

Results from this dose-response meta-analysis suggest that coffee consumption may be inversely associated with the risk of fatal PCa. No clear evidence of an association with PCa incidence was observed.

Coffee consumption and risk of prostate cancer: an up-to-date meta-analysis

BACKGROUND/OBJECTIVES

Epidemiologic findings concerning the association between coffee consumption and prostate cancer risk yielded mixed results. We aimed to investigate the association by performing a meta-analysis of all available studies.

SUBJECTS/METHODS

We searched PubMed, Web of Science and EMBASE for studies published up to July 2013. We calculated the summary relative risk (RR) and 95% confidence intervals (CIs) for ever, moderate and highest consumption of coffee vs non/lowest consumption. The dose-response relationship was assessed by restricted cubic spline model and multivariate random-effect meta-regression.

RESULTS

A total of 12 case-control studies and 12 cohort studies with 42,179 cases were selected for final meta-analysis. No significant associations were found among overall analysis. A borderline positive association was found for highest drinkers in five small hospital-based case-control (HCC) studies involving 2278 cases. However, compared with non/lowest drinkers, the summary RRs were 0.92 (95% CI=0.85-0.99) for ever drinkers, 0.92 (95% CI=0.85-1.00) for moderate drinkers and 0.83 (95% CI=0.72-0.96) for highest drinkers from 12 cohort studies, comprising a total of 34,424 cases. An increase in coffee intake of two cups/day was associated with a 7% decreased risk of prostate cancer according to cohort studies. A significant inverse relationship was also found for fatal prostate cancers and high-grade prostate cancers.

CONCLUSIONS

Case-control studies especially HCC ones might be prone to selection bias and recall bias that might have contributed to the conflicting results. Therefore, the present meta-analysis suggests a borderline significant inverse association between coffee consumption and prostate cancer risk based on cohort studies.