Sex-specific association between coffee consumption and incident chronic kidney disease: a population-based analysis of 359,906 participants from the UK Biobank.

BACKGROUND: The risk for chronic kidney disease (CKD) is influenced by genetic predisposition, sex, and lifestyle. Previous research indicates that coffee is a potentially protective factor in CKD. The current study aims to investigate whether sex disparity exists in the coffee-CKD association, and whether genetic risk of CKD or genetic polymorphisms of caffeine metabolism affect this association. METHODS: A total of 359,906 participants from the UK Biobank who were enrolled between 2006 and 2010 were included in this prospective cohort study, which aimed to estimate the hazard ratios for coffee intake and incident CKD using a Cox proportional hazard model. Allele scores of CKD and caffeine metabolism were additionally adjusted for in a subsample with qualified genetic data ( n = 255,343). Analyses stratified by genetic predisposition, comorbidities, and sex hormones were performed. Tests based on Bayesian model averaging were conducted to ascertain the robustness of the results. RESULTS: Coffee was inversely associated with CKD in a dose-dependent manner. The effects of coffee did not differ across different strata of genetic risk for CKD, but were more evident among slower genetically predicted caffeine metabolizers. Significant sex disparity was observed ( P value for interaction = 0.013), in that coffee drinking was only associated with the risk reduction of CKD in females. Subgroup analysis revealed that testosterone and sex hormone-binding globulin (SHBG), but not estradiol, modified the coffee-CKD association. CONCLUSIONS: In addition to the overall inverse coffee-CKD association that was observed in the general population, we could also establish that a sex disparity existed, in that females were more likely to experience the benefit of the association. Testosterone and SHBG may partly account for the sex disparity.

Medical conditions associated with coffee consumption: Disease-trajectory and comorbidity network analyses of a prospective cohort study in UK Biobank.

BACKGROUND: Habitual coffee consumption has been associated with multiple health benefits. A comprehensive analysis of disease trajectory and comorbidity networks in relation to coffee consumption is, however, currently lacking. OBJECTIVES: We aimed to comprehensively examine the health outcomes associated with habitual coffee consumption, through clarifying its disease trajectory and comorbidity networks. METHODS: Based on the UK Biobank cohort, we included 395,539 individuals with available information on coffee intake collected at recruitment between 2006 and 2010. These individuals were categorized as having low (<1 cup per day), moderate (1-3 cups), and high (≥4 cups) levels of coffee intake, and were followed through 2020 to ascertain 496 medical conditions. Cox regression was used to assess the associations between high-level coffee intake and the risk of medical conditions with a prevalence ≥0.5% in the study population, after adjusting for multiple confounders, using low-level coffee intake as the reference. Disease-trajectory and comorbidity network analyses were then applied to visualize the temporal and nontemporal relationships between the medical conditions that had an inverse association with high-level coffee intake. RESULTS: During a median follow-up of 11.8 years, 31 medical conditions were found to be associated with high-level coffee intake, among which 30 showed an inverse association (HRs ranged from 0.61 to 0.94). The inverse associations were more pronounced for women, compared with men. Disease-trajectory and comorbidity network analyses of these 30 conditions identified 4 major clusters of medical conditions, mainly in the cardiometabolic and gastrointestinal systems, among both men and women; 1 cluster of medical conditions following alcohol-related disorders, primarily among men; as well as a cluster of estrogen-related conditions among women. CONCLUSIONS: Habitual coffee consumption was associated with lower risks of many medical conditions, especially those in the cardiometabolic and gastrointestinal systems and those related to alcohol use and estrogen regulation.

Type of tea consumption and depressive symptoms in Chinese older adults.

BACKGROUND: Existing research indicates that tea drinking may exert beneficiary effects on mental health. However, associations between different types of tea intake and mental health such as depression have not been fully examined. The purpose of this study was to examine the associations of green tea, fermented tea, and floral tea consumption with depressive symptoms. METHODS: We used data from the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey, a nationwide survey on older adults in mainland China. A total of 13,115 participants (mean age 83.7 years, 54.2% were women) with valid responses were included in the analysis. The type (green, fermented [black, Oolong, white, yellow, dark, and compressed teas], and floral) and the frequency of tea consumption were recorded, and depressive symptoms were assessed using 10-item of the Center for Epidemiologic Studies Depression Scale (CES-D-10). We examined the associations between the type and the frequency of tea intake and depression, controlling for a set of demographic, socioeconomic, psychosocial, behavioral, and health-related variables. RESULTS: Overall, intakes of green tea, fermented tea, and floral tea were all significantly associated with lower prevalence of depressive symptoms, independent of other risk factors. Compared with the group of no tea intake, the adjusted ORs of depressive symptoms for daily green tea, fermented tea, and floral tea intake were 0.85 (95% CI: 0.76-0.95), 0.87 (95% CI: 0.76-0.99), and 0.70 (95% CI: 0.59-0.82), respectively. Linear associations were observed between the frequencies of all three types of tea intake and depressive symptoms (P < 0.05 for trends for all three types). The associations of the type and the frequency of tea intake and depressive symptoms were robust in several sensitivity analyses. CONCLUSIONS: Among Chinese older adults, regularly consumed any type of tea (green, fermented, or floral) were less likely to show depressive symptoms, the associations seemed more pronounced among floral tea and green tea drinkers.

Activation of CO2-reducing methanogens in oil reservoir after addition of nutrient.

Nutrient addition as part of microbial enhanced oil recovery (MEOR) operations have important implications for more energy recovery from oil reservoirs, but very little is known about the in situ response of microorganisms after intervention. An analysis of two genes as biomarkers, mcrA encoding the key enzyme in methanogenesis and fthfs encoding the key enzyme in acetogenesis, was conducted during nutrient addition in oil reservoir. Clone library data showed that dominant mcrA sequences changed from acetoclastic (Methanosaetaceae) to CO2-reducing methanogens (Methanomicrobiales and Methanobacteriales), and the authentic acetogens affiliated to Firmicutes decreased after the intervention. Principal coordinates analysis (PCoA) and Jackknife environment clusters revealed evidence on the shift of the microbial community structure among the samples. Quantitative analysis of methanogens via qPCR showed that Methanobacteriales and Methanomicrobiales increased after nutrient addition, while acetoclastic methanogens (Methanosaetaceae) changed slightly. Nutrient treatment activated native CO2-reducing methanogens in oil reservoir. The high frequency of Methanobacteriales and Methanomicrobiales (CO2-reducers) after nutrient addition in this petroleum system suggested that CO2-reducing methanogenesis was involved in methane production. The nutrient addition could promote the methane production. The results will likely improve strategies of utilizing microorganisms in subsurface environments.