MTNR1B genotype and effects of carbohydrate quantity and dietary glycaemic index on glycaemic response to an oral glucose load: the OmniCarb trial.

AIMS/HYPOTHESIS: A type 2 diabetes-risk-increasing variant, MTNR1B (melatonin receptor 1B) rs10830963, regulates the circadian function and may influence the variability in metabolic responses to dietary carbohydrates. We investigated whether the effects of carbohydrate quantity and dietary glycaemic index (GI) on glycaemic response during OGTTs varied by the risk G allele of MTNR1B-rs10830963. METHODS: This study included participants (n=150) of a randomised crossover-controlled feeding trial of four diets with high/low GI levels and high/low carbohydrate content for 5 weeks. The MTNR1B-rs10830963 (C/G) variant was genotyped. Glucose response during 2 h OGTT was measured at baseline and the end of each diet intervention. RESULTS: Among the four study diets, carrying the risk G allele (CG/GG vs CC genotype) of MTNR1B-rs10830963 was associated with the largest AUC of glucose during 2 h OGTT after consuming a high-carbohydrate/high-GI diet (ß 134.32 [SE 45.69] mmol/l × min; p=0.004). The risk G-allele carriers showed greater increment of glucose during 0-60 min (ß 1.26 [0.47] mmol/l; p=0.008) or 0-90 min (ß 1.10 [0.50] mmol/l; p=0.028) after the high-carbohydrate/high-GI diet intervention, but not after consuming the other three diets. At high carbohydrate content, reducing GI levels decreased 60 min post-OGTT glucose (mean -0.67 [95% CI: -1.18, -0.17] mmol/l) and the increment of glucose during 0-60 min (mean -1.00 [95% CI: -1.67, -0.33] mmol/l) and 0-90 min, particularly in the risk G-allele carriers (pinteraction <0.05 for all). CONCLUSIONS/INTERPRETATION: Our study shows that carrying the risk G allele of MTNR1B-rs10830963 is associated with greater glycaemic responses after consuming a diet with high carbohydrates and high GI levels. Reducing GI in a high-carbohydrate diet may decrease post-OGTT glucose concentrations among the risk G-allele carriers.

Cardiovascular Health and Life Expectancy Among Adults in the United States.

BACKGROUND: Cardiovascular disease may be the main reason for stagnant growth in life expectancy in the United States since 2010. The American Heart Association recently released an updated algorithm for evaluating cardiovascular health (CVH)-Life's Essential 8 (LE8) score. We aimed to quantify the associations of CVH levels, estimated by the LE8 score, with life expectancy in a nationally representative sample of US adults. METHODS: We included 23 003 nonpregnant, noninstitutionalized participants aged 20 to 79 years who participated in the National Health and Nutrition Examination Survey from 2005 to 2018 and whose mortality was identified through linkage to the National Death Index through December 31, 2019. The overall CVH was evaluated by the LE8 score (range, 0-100), as well as the score for each component of diet, physical activity, tobacco/nicotine exposure, sleep duration, body mass index, non-high-density lipoprotein cholesterol, blood glucose, and blood pressure. Life table method was used to estimate life expectancy by levels of the CVH. RESULTS: During a median of 7.8 years of follow-up, 1359 total deaths occurred. The estimated life expectancy at age 50 years was 27.3 years (95% CI, 26.1-28.4), 32.9 years (95% CI, 32.3-33.4), and 36.2 years (95% CI, 34.2-38.2) in participants with low (LE8 score <50), moderate (50≤ LE8 score <80), and high (LE8 score ≥80) CVH, respectively. Equivalently, participants with high CVH had an average 8.9 (95% CI, 6.2-11.5) more years of life expectancy at age 50 years compared with those with low CVH. On average, 42.6% of the gained life expectancy at age 50 years from adhering to high CVH was attributable to reduced cardiovascular disease death. Similarly significant associations of CVH with life expectancy were observed in men and women, respectively. Similarly significant associations of CVH with life expectancy were observed in White participants and Black participants but not in Mexican participants. CONCLUSIONS: Adhering to a high CVH, defined as the LE8 score, is related to a considerably increased life expectancy in US adults, but more research needs to be done in other races and ethnicities (eg, Hispanic and Asian).

Degree of joint risk factor control and hazard of mortality in diabetes patients: a matched cohort study in UK Biobank.

BACKGROUND: Diabetes patients are at higher risk for mortality than the general population; however, little is known about whether the excess mortality risk associated with diabetes could be mitigated or nullified via controlling for risk factors. METHODS: We included 18,535 diabetes patients and 91,745 matched individuals without diabetes without baseline cancer or cardiovascular disease (CVD), followed up from 2006 to 2021. The main exposure was the number of optimized risk factors including glycated hemoglobin < 53 mmol/mole, systolic blood pressure < 140 mmHg and diastolic blood pressure < 90 mmHg, no albuminuria, non-current smoking and low-density lipoprotein cholesterol (LDL-C) < 2.5 mmol/L. We used Cox proportional hazards models to explore the association of the degree of risk factor control with all-cause mortality, cancer mortality, CVD mortality and other mortality. RESULTS: Each additional risk factor control was associated with a 16, 10, 21 and 15% lower risk of all-cause mortality, cancer mortality, CVD mortality and other mortality, respectively. Optimal risk factors control (controlling 5 risk factors) was associated with a 50% (HR 0.50, 95% CI 0.41-0.62), 74% (HR 0.26, 95% CI 0.16-0.43) and 38% (HR 0.62, 95% CI 0.44-0.87) lower risk of all-cause mortality, CVD mortality and other mortality, respectively. Diabetes patients with 4, 3 and 5 or more controlled risk factors, respectively, showed no excess risk of all-cause mortality, cancer mortality and CVD mortality compared to matched non-diabetes patients. CONCLUSIONS: The results from this study indicate that optimal risk factor control may eliminate diabetes-related excess risk of all-cause mortality, CVD mortality and other mortality.

Smoking Timing, Healthy Diet, and Risk of Incident CKD Among Smokers: Findings From UK Biobank.

RATIONALE & OBJECTIVE: While smoking is a recognized risk factor for chronic kidney disease (CKD), the relationship between the time smoking is initiated after awakening each day and CKD remains largely unstudied. This study examined the association between this timing and the risk of CKD, and the potential interactions of smoking timing with other risk factors for the occurrence of CKD. STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: A total of 32,776 participants in the UK Biobank with complete data on the time from waking to the first cigarette and free of prevalent CKD were included. EXPOSURE: Time from waking to the first cigarette. OUTCOME: Incident CKD cases. ANALYTICAL APPROACH: Cox proportional hazards regression was used to investigate the associations between the time smoking is initiated each day and the risk of CKD. The potential interactions of smoking timing with risk factors in relationship to CKD risk were assessed on both multiplicative and additive scales. RESULTS: During a median follow-up of 12 years, 940 incident CKD cases occurred. Shorter durations of time from waking to the first cigarette were associated with a higher risk of incident CKD (P-trend=0.01). Compared to >120 minutes, the adjusted hazard ratio (HR) associated with smoking timing was 1.28 (95% CI: 0.92-1.80) for 61-120 minutes, 1.48 (95% CI: 1.11-1.96) for 30-60 minutes, 1.36 (95% CI: 1.01-1.88) for 5-15 minutes, and 1.70 (95% CI: 1.22-2.37) for <5 minutes, respectively. Furthermore, there was a significant additive interaction and multiplicative interactions between the timing of smoking and a healthy diet score (P for additive interaction=0.01, P for multiplicative interaction=0.004). LIMITATIONS: Generalizability; Possible residual confounding limiting causal inference. CONCLUSION: These findings reveal a significant association between the shorter time from waking to the first cigarette and a higher CKD risk. The magnitude of these associations were greater in the setting of an unhealthy diet.

Spontaneous miscarriage and social support in predicting risks of depression and anxiety: a cohort study in UK Biobank.

BACKGROUND: It is still unclear whether social support can moderate the high risk of depression and anxiety due to spontaneous miscarriage. OBJECTIVE: This study prospectively investigated the associations of spontaneous miscarriage with risks of depression and anxiety, and evaluated the interactions between spontaneous miscarriage and the degree of social support in relation to depression and anxiety risks. STUDY DESIGN: A total of 179,000 participants from the UK Biobank with pregnancy experience and without depression or anxiety at baseline were included. Spontaneous miscarriage was defined by self-report from participants at enrollment or by International Classification of Diseases codes. The degree of social support was defined as the number of social support factors including living with a spouse or partner, participation in social activities, and confiding. Cox proportional hazards models were used to evaluate the joint association of spontaneous miscarriage and social support with the risks of depression and anxiety. RESULTS: During a median follow-up of 12.3 years, 4939 depression incidents and 5742 anxiety incidents were documented. For participants with 1, 2, and ≥3 spontaneous miscarriages, hazard ratios (95% confidence intervals) for depression were 1.10 (1.02-1.19), 1.31 (1.14-1.50), and 1.40 (1.18-1.67), respectively (P trend <.001), compared with participants without a history of spontaneous miscarriage, after adjustment for covariates. For anxiety, the hazard ratios (95% confidence intervals) were 1.07 (1.00-1.15), 1.04 (0.90-1.19), and 1.21 (1.02-1.44), respectively (P trend=.01). Moreover, we found that the risk of depression associated with a combination of spontaneous miscarriage and low degree of social support in later life was greater than the sum of the risks associated with each individual factor, indicating significant interactions on an additive scale (P interaction=.03). CONCLUSION: Spontaneous miscarriage is associated with higher risks of depression and anxiety, and the risk of depression is further increased when there is also low degree of social support.

Smoking timing, genetic susceptibility and the risk of incident type 2 diabetes: A cohort study from the UK Biobank.

AIM: To prospectively assess the association of smoking timing with the risk of type 2 diabetes (T2D) and examine whether smoking amount or genetic susceptibility might modify the relationship. MATERIALS AND METHODS: A total of 294 815 participants without diabetes from the UK Biobank, including non-smokers and smokers with data on the time from waking to first cigarette, were included. Cox proportional hazards models were used to evaluate the association between smoking timing and the risk of incident T2D. RESULTS: During a median follow-up time of 12 years, a total of 9937 incident cases of T2D were documented. Compared with non-smokers, a shorter time from waking to first cigarette was significantly associated with a higher risk of incident T2D (P for trend < .001). In the fully adjusted model, the hazard ratios (HRs) (95% confidence interval) associated with smoking timing were 1.46 (1.17-1.81) for more than 2 hours, 1.51 (1.21-1.87) for 1-2 hours, 1.58 (1.34-1.85) for 30-60 minutes, 1.86 (1.57-2.21) for 5-15 minutes and 2.01 (1.60-2.54) for less than 5 minutes. We found that even among those who reported being light smokers, those with the shortest time from waking to first cigarette had a 105% higher risk of T2D with an HR of 2.05 (1.52-2.76), which was comparable with heavy smokers. The genetic risk score for T2D did not modify this association (P-interaction = .51). CONCLUSIONS: Our findings indicate that shorter time from waking to first cigarette is significantly associated with a higher risk of incident T2D.

Body composition, lifestyle, and depression: a prospective study in the UK biobank.

BACKGROUND: Obesity has been related to depression and adhering healthy lifestyle was beneficial to lower the risk of depression; however, little is known about the relationship between body composition and fat distribution with depression risk and the influence of body composition and fat distribution on the association of lifestyle and depression. Therefore, we aimed to investigate whether body composition and fat distribution were associated with the adverse events of depression and the relationship between lifestyle and depression. METHODS: We included 330,131 participants without depression at baseline in the UK Biobank (mean age, 56.9 years; 53.83% females). The assessment of depression was sourced from health outcomes across self-report, primary care, hospital inpatient data, and death data. Body composition was determined by bioelectrical impedance. Seven lifestyles (no current smoking, moderate alcohol consumption, regular physical activity, healthy diet, less sedentary behavior, healthy sleep pattern, and appropriate social connection) were used to generate a lifestyle score. RESULTS: During a median of 11.7 years of follow-up, 7576 incident depression occurred. All the body composition measures were positively associated with depression risk, with the Hazard ratios (HR) for the uppermost tertile (T3) versus the lowest tertile (T1) ranging from 1.26 (95% CI: 1.15-1.39) for trunk fat-free mass (TFFM) to 1.78 (1.62-1.97) for leg fat percentage (LFP). In addition, we found significant interactions between fat mass-related indices, especially leg fat mass (LFM) (p = 1.65 × 10-9), and lifestyle score on the risk of depression, for which the beneficial associations of a healthy lifestyle with the risk of depression were more evident among participants with low body fat measurement. CONCLUSIONS: High levels of body composition measures were associated with an increased depression risk. Adverse body composition measures may weaken the link between a healthy lifestyle and a reduced risk of depression.

Joint association of loneliness and traditional risk factor control and incident cardiovascular disease in diabetes patients.

AIMS: To investigate the prospective associations of the loneliness and social isolation scales with cardiovascular disease (CVD) risk in diabetes patients and compare the relative importance of loneliness and social isolation with traditional risk factors. Also, the interactions of loneliness or isolation with the degree of risk factor control in relation to CVD risk were evaluated. METHODS AND RESULTS: A total of 18 509 participants diagnosed with diabetes from the UK Biobank were included. A two-item scale and a three-item scale were used to assess loneliness and isolation levels, respectively. The degree of risk factor control was defined as numbers of glycated hemoglobin (HbA1c), blood pressure (BP), low-density lipoprotein cholesterol (LDL-C), smoking, and kidney condition controlled within the target range. During a mean follow-up of 10.7 years, 3247 total CVD incidents were documented, including 2771 coronary heart disease and 701 strokes. In the fully adjusted model, compared with participants with the lowest loneliness score (zero), hazard ratios (95% confidence interval) for CVD were 1.11 (1.02 and 1.20) and 1.26 (1.11 and 1.42) for participants with a loneliness scale of 1 and 2, respectively (P-trend < 0.001). No significant associations were observed for social isolation. Loneliness ranked higher in relative strength for predicting CVD than the lifestyle risk factors in diabetes patients. A significant additive interaction between loneliness and the degree of risk factor control on the risk of CVD was observed (P for additive interaction = 0.005). CONCLUSION: Among diabetes patients, loneliness, but not social isolation scale, is associated with a higher risk of CVD and shows an additive interaction with the degree of risk factor control.

Adding salt to foods and hazard of premature mortality.

AIMS: We analyzed whether the frequency of adding salt to foods was associated with the hazard of premature mortality and life expectancy. METHODS AND RESULTS: A total of 501 379 participants from UK biobank who completed the questionnaire on the frequency of adding salt to foods at baseline. The information on the frequency of adding salt to foods (do not include salt used in cooking) was collected through a touch-screen questionnaire at baseline. We found graded relationships between higher frequency of adding salt to foods and higher concentrations of spot urinary sodium or estimated 24-h sodium excretion. During a median of 9.0 years of follow-up, 18 474 premature deaths were documented. The multivariable hazard ratios [95% confidence interval (CI)] of all-cause premature mortality across the increasing frequency of adding salt to foods were 1.00 (reference), 1.02 (0.99, 1.06), 1.07 (1.02, 1.11), and 1.28 (1.20, 1.35) (P-trend < 0.001). We found that intakes of fruits and vegetables significantly modified the associations between the frequency of adding salt to foods and all-cause premature mortality, which were more pronounced in participants with low intakes than those with high intakes of these foods (P-interaction = 0.02). In addition, compared with the never/rarely group, always adding salt to foods was related to 1.50 (95% CI, 0.72-2.30) and 2.28 (95% CI, 1.66-2.90) years lower life expectancy at the age of 50 years in women and men, respectively. CONCLUSIONS: Our findings indicate that higher frequency of adding salt to foods is associated with a higher hazard of all-cause premature mortality and lower life expectancy.

Adherence to a healthy sleep pattern is associated with lower risks of all-cause, cardiovascular and cancer-specific mortality.

BACKGROUND: Individual unhealthy sleep behaviours have been associated with increased risks of all-cause mortality and deaths due to cardiovascular disease (CVD) or cancer. The evidence regarding the association of sleep patterns with these risks is limited. OBJECTIVE: To examine the associations of sleep patterns with all-cause, CVD and cancer mortality in a large prospective cohort. METHODS: This prospective cohort study included 283,443 adults from UK Biobank without CVD and cancer at baseline. We created a healthy sleep score and sleep patterns combining five individual sleep behaviours. RESULTS: During a mean (standard deviation) of 8.9 (1.1) years (2.5 million person-years) of follow up, a total of 7936 all-cause deaths, 762 CVD-caused deaths, and 4540 cancer-caused deaths occurred during follow up. One point increase of the healthy sleep score was associated with a 4-11% lower risk of all-cause mortality (Hazard Ratio [HR], 0.94; 95% CI, 0.92-0.96), CVD mortality (HR, 0.89; 95% CI, 0.83-0.95) and cancer mortality (HR, 0.96; 95% CI, 0.93-0.99), with adjustment for age, sex, assessment centres, smoking status, alcohol intake status, socioeconomic status and physical activity. Compared with participants with an unfavourable sleep pattern, those with a favourable sleep pattern had 24-42% lower risks of all-cause and CVD mortality. The association with all-cause mortality tended to be stronger among underweight participants and those with insufficient physical activity. CONCLUSIONS: A healthy sleep pattern was associated with lower risks of all-cause mortality and mortality from CVD and cancer. Our findings highlight the importance of improving overall sleep behaviours in lowering mortality.

Educational attainment and drinking behaviors: Mendelian randomization study in UK Biobank.

Educational attainment has been associated with drinking behaviors in observation studies. We performed Mendelian randomization analysis to determine whether educational attainment causally affected drinking behaviors, including amount of alcohol intakes (in total and various types), drinking frequency, and drinking with or without meals among 334,507 white British participants from the UK Biobank cohort. We found that genetically instrumented higher education (1 additional year) was significantly related to higher total amount of alcohol intake (inverse-variance weighted method (IVW): beta = 0.44, 95% confidence interval (CI) 0.40-0.49, P = 1.57E-93). The causal relations with total amount and frequency of alcohol drinking were more evident among women. In analyses of different types of alcohol, higher educational attainment showed the strongest causal relation with more consumption of red wine (IVW beta = 0.34, 95% CI 0.32-0.36, P = 2.65E-247), followed by white wine/champagne, in a gender-specific manner. An inverse association was found for beer/cider and spirits. In addition, we found that 1 additional year of educational attainment was causally related to higher drinking frequency (IVW beta = 0.54, 95% CI 0.51-0.57, P = 4.87E-230) and a higher likelihood to take alcohol with meals (IVW: odds ratio (OR) = 3.10, 95% CI 2.93-3.29, P = 0.00E + 00). The results indicate causal relations of higher education with intake of more total alcohol especially red wine, and less beer/cider and spirits, more frequent drinking, and drinking with meals, suggesting the importance of improving drinking behaviors, especially among people with higher education.

Changes in bile acid subtypes and long-term successful weight-loss in response to weight-loss diets: The POUNDS lost trial.

BACKGROUND AND AIMS: Primary bile acids (BAs) are synthesized in the liver and secondary BAs result from intestinal microbial activity. Different subtypes of BAs may be involved in regulating adiposity and energy homeostasis. We examined how changes in circulating BA subtypes induced by weight-loss diets were associated with improvements in adiposity, regional fat deposition and energy metabolism among overweight and obese adults. METHODS: The study included 551 subjects who participated in a 2-year weight-loss diet intervention trial. Circulating 14 BA subtypes (primary and secondary unconjugated BAs and their taurine-/glycine-conjugates) were measured at baseline and 6 months. Associations of changes in BAs with changes in weight, waist circumference, resting energy expenditure (REE), body fat composition and fat distribution were evaluated. RESULTS: Greater decreases in primary BAs (cholate and chenodeoxycholate) and secondary BAs (deoxycholate and lithocholate) and their conjugates (except for glycolithocholate) were associated with more decreases in weight and waist circumference at 6 months (P-after-false-discovery-rate-correction [PFDR ] < .05). We found that changes in glycocholate and glycoursodeoxycholate were consistently associated with reductions of general and central adiposity, REE, whole-body fat and visceral adipose tissue (PFDR  < .05). Further, the initial (6-month) changes in BA subtypes were differently predictive of successful weight loss over 2 years. CONCLUSIONS: The decreases in primary and secondary BA subtypes after eating low-calorie weight-loss diets were significantly associated with improving adiposity, fat accumulation and energy metabolism, suggesting that specific BA subtypes would be predictive of long-term successful weight loss and individuals' response to the treatment of weight-loss diets.

Duration and Life-Stage of Antibiotic Use and Risks of All-Cause and Cause-Specific Mortality: Prospective Cohort Study.

Rationale: The overuse of antibiotics has been an important clinical issue, and antibiotic exposure is linked to alterations in gut microbiota, which has been related to risks of various chronic diseases such as cardiovascular disease and cancer. Also, duration of antibiotic exposure may be a risk factor of premature death. Objective: We investigated associations of life-stage and duration of antibiotic use during adulthood with risks of all-cause and cause-specific mortality. Methods and Results: This prospective cohort study included 37 516 women aged ≥60 years who were free of cardiovascular disease or cancer from the Nurses' Health Study. Participants reported a total amount of time they used antibiotics (none, <15 days, 15 days to <2 months, or ≥2 months) in the middle- (age, 40-59) and late adulthood (age, 60 or older). We estimated hazard ratios for all-cause mortality and deaths from cardiovascular disease or cancer over 10 years according to duration of antibiotic use. During 355 918 person-years of follow-up, we documented 4536 deaths from any cause (including 728 cardiovascular deaths and 1206 cancer deaths). As compared with women who did not use antibiotics, those who used them for ≥2 months in late adulthood had increased risks of all-cause mortality (hazard ratio, 1.16 [95% CI, 1.01-1.33]) and cardiovascular mortality (hazard ratio, 1.49 [95% CI, 1.04-2.13]), but not cancer mortality (hazard ratio, 0.85 [95% CI, 0.65-1.12]) after adjustment for chronic metabolic diseases, antibiotic use during middle adulthood, indication for use, demographic factors, and lifestyle/dietary factors. The association was more evident among women who also used antibiotics in middle-adulthood than among those who did not use during this life-stage. Conclusions: Long-term use of antibiotics in late adulthood may be a risk factor for all-cause and cardiovascular mortality. The unfavorable effect of antibiotic exposure for subsequent risks of deaths due to chronic diseases needs to be considered.

Changes in pedometer-measured physical activity are associated with weight loss and changes in body composition and fat distribution in response to reduced-energy diet interventions: The POUNDS Lost trial.

AIMS: To examine whether changes in objectively measured physical activity (PA) are associated with weight loss and changes in body composition and fat distribution in response to weight-loss diet interventions. METHODS: This study included 535 participants with overweight/ obesity, who were randomly assigned to four weight-loss diets varying in macronutrients. PA was measured objectively with pedometers, and body composition and fat distribution were measured using dual-energy X-ray absorptiometry and computed tomography scans at baseline, 6 months and 24 months. RESULTS: From baseline to 6 months, when the maximum weight loss was achieved, each 1000-steps/d increment in PA was associated with a greater reduction in body weight (ß[SE] = -0.48[0.11]) and waist circumference (ß[SE] = -0.49[0.12]). Similar inverse associations were found in changes in body composition and fat distribution (P < 0.05 and false discovery rate qvalue < 0.1 for all). The trajectory of the above adiposity measures across the 24-month intervention period differed between the patterns of PA change. Participants with the largest increase in PA maintained their weight loss from 6 months to 24 months, while those with a smaller increase in PA regained their weight. In addition, dietary fat or protein intake significantly modified the associations between changes in PA and changes in body weight and waist circumference over 24 months (P∆PA*diet < 0.05). CONCLUSIONS: Changes in objectively measured PA were inversely related to changes in body weight, body composition and fat distribution in response to weight-loss diets, and such associations were more evident in people on a high-fat or average-protein diet compared with a low-fat or high-protein diet.

Red meat consumption and all-cause and cardiovascular mortality: results from the UK Biobank study.

PURPOSE: To investigate the prospective associations between red meat consumption and all-cause and cardiovascular diseases (CVD) mortality, and to assess the modification effects of lifestyle and genetic risk factors. METHODS: 180,642 individuals free of CVD or cancer were enrolled from 2006 to 2010 and followed up to 2018 in the UK Biobank. Information on demographics, lifestyles, and medical history was collected through a baseline touchscreen questionnaire. The information on diet was collected through a single touchscreen food-frequency questionnaire. A total of ten single-nucleotide polymorphisms were used to calculate the genetic risk score (GRS) of trimethylamine N-oxide (TMAO), a gut microbiota metabolite from red meat. Adjusted Cox proportional hazard regression models were used to assess the association of red meat consumption with mortality. RESULTS: We documented 3596 deaths [655 CVD deaths, 285 coronary heart disease (CHD) deaths, and 149 stroke deaths] during median 8.6 years of follow-up. Compared with the lowest red meat intake (< 1.5 times/week), the highest red meat intake (≥ 3.0 times/week) was associated with a 20%, 53%, and 101% elevated risk for CVD, CHD, and stroke mortality (P for trend = 0.04, 0.007, and 0.02, respectively), but not all-cause mortality. We found that the associations between red meat intake and mortality were not modified by dietary and lifestyle factors, as well as TMAO GRS. In addition, substitution analyses showed that a decrease in red meat consumption and an increase in the consumption of poultry or cereal was significantly associated with 9%-16% lower CVD or CHD mortality risk. CONCLUSION: Our results indicated that red meat consumption was associated with higher risks of CVD, CHD, and stroke mortality, and the associations were not modified by lifestyle and genetic risk factors. Replacing red meat by poultry or cereal was related to lower risks of CVD and CHD mortality.

Ten-year changes in plasma L-carnitine levels and risk of coronary heart disease.

PURPOSE: L-Carnitine is abundant in animal source foods, particularly red meat, and circulating L-carnitine may be related to the incidence of coronary heart disease (CHD). We investigated whether long-term changes in plasma L-carnitine over 10 years were associated with the CHD incidence and also examined joint associations of carnitine-rich red meat consumption and L-carnitine changes on the subsequent risk of CHD. METHODS: This prospective nested case-control study included 772 healthy women at baseline (386 incident CHD cases and 386 healthy controls). Plasma L-carnitine levels were measured both at the first (1989-90) and second blood collections (2000-02). Incident cases of CHD were prospectively followed from the date of the second blood collection through 2016. RESULTS: Overall, a greater increase in L-carnitine from the first to the second time point was related to a higher risk of CHD, regardless of the initial L-carnitine levels (relative risk: 1.36 (95% CI 0.999, 1.84) per 1-SD increase). The 10-year changes in L-carnitine were positively associated with red meat consumption over time, and women with higher red meat intake (≥ 36 g/day) and with greater increases in L-carnitine had a 1.86 (95% CI 1.13, 3.09) times increased risk of CHD, as compared to those with lower red meat intake and lesser increases in L-carnitine. CONCLUSION: Long-term increases in L-carnitine levels were associated with the subsequent incidence of CHD, especially among women with higher intake of red meat. Our results suggest the importance of atherogenic L-carnitine changes and dietary intakes over time in the prevention of CHD.

Joint exposure to various ambient air pollutants and incident heart failure: a prospective analysis in UK Biobank.

AIMS: Little is known about the relation between the long-term joint exposure to various ambient air pollutants and the incidence of heart failure (HF). We aimed to assess the joint association of various air pollutants with HF risk and examine the modification effect of the genetic susceptibility. METHODS AND RESULTS: This study included 432 530 participants free of HF, atrial fibrillation, or coronary heart disease in the UK Biobank study. All participants were enrolled from 2006 to 2010 and followed up to 2018. The information on particulate matter (PM) with diameters ≤2.5 µm (PM2.5), ≤10 µm (PM10), and between 2.5 and 10 µm (PM2.5-10) as well as nitrogen oxides (NO2 and NOx) was collected. We newly proposed an air pollution score to assess the joint exposure to the five air pollutants through summing each pollutant concentration weighted by the regression coefficients with HF from single-pollutant models. We also calculated the weighted genetic risk score of HF. During a median of 10.1 years (4 346 642 person-years) of follow-up, we documented 4201 incident HF. The hazard ratios (HRs) [95% confidence interval (CI)] of HF for a 10 µg/m3 increase in PM2.5, PM10, PM2.5-10, NO2, and NOx were 1.85 (1.34-2.55), 1.61 (1.30-2.00), 1.13 (0.80-1.59), 1.10 (1.04-1.15), and 1.04 (1.02-1.06), respectively. We found that the air pollution score was associated with an increased risk of incident HF in a dose-response fashion. The HRs (95% CI) of HF were 1.16 (1.05-1.28), 1.19 (1.08-1.32), 1.21 (1.09-1.35), and 1.31 (1.17-1.48) in higher quintile groups compared with the lowest quintile of the air pollution score (P trend <0.001). In addition, we observed that the elevated risk of HF associated with a higher air pollution score was strengthened by the genetic susceptibility to HF. CONCLUSION: Our results indicate that the long-term joint exposure to various air pollutants including PM2.5, PM10, PM2.5-10, NO2, and NOx is associated with an elevated risk of incident HF in an additive manner. Our findings highlight the importance to comprehensively assess various air pollutants in relation to the HF risk.

Changes in gut-microbiota-related metabolites and long-term improvements in lipoprotein subspecies in overweight and obese adults: the POUNDS lost trial.

BACKGROUND/OBJECTIVES: Alterations in gut microbiota have been linked to obesity and impaired lipid metabolism. Lipoproteins are heterogeneous, and lipoprotein subspecies containing apolipoprotein C-III (apoCIII) have adverse associations with obesity and related cardiometabolic abnormalities. We investigated associations of weight-loss diet-induced decreases in atherogenic gut-microbial metabolites, trimethylamine N-oxide (TMAO) and L-carnitine, with improvements in atherogenic lipoproteins containing apoCIII among patients with obesity. SUBJECTS/METHODS: This study included overweight and obese adults who participated in a 2-year weight-loss dietary intervention, the POUNDS Lost trial. Blood levels of TMAO and L-carnitine were measured at baseline and 6 months after the intervention; 6-month changes in the metabolites were calculated. We evaluated 2-year changes in lipid profiles (n = 395) and cholesterol [Chol] in lipoprotein (very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL)) subfractions defined by the presence or absence of apoCIII (n = 277). RESULTS: The initial (6-month) decrease in L-carnitine was significantly associated with long-term (2-year) reductions in non-HDL-Chol and LDL-Chol (p < 0.05). Also, the decrease in L-carnitine was significantly related to decreases in Chol in LDL with apoCIII (p = 0.034) and Chol in [LDL + VLDL] with apoCIII (p = 0.018). We found significant interactions between dietary fat and TMAO on changes in LDL-Chol (Pinteraction = 0.013) and Chol in [LDL + VLDL] with apoCIII (Pinteraction = 0.0048); a greater increase in TMAO was related to lesser improvements in the lipoprotein outcomes if participants consumed a high-fat compared to a low-fat diet. CONCLUSIONS: Changes in TMAO and L-carnitine induced by weight-loss diets were associated with long-term improvements in atherogenic lipoproteins containing apoCIII, implicating that these metabolic changes might be predictive of an individual's response to the dietary treatment to modify the unfavorable lipid profiles in obese patients. Dietary fat intake might modify associations of TMAO changes with long-term improvements of atherogenic cholesterol metabolism in overweight and obese adults. CLINICALTRIALS. GOV IDENTIFIER: NCT00072995.

Type 2 Diabetes and Hypertension.

RATIONALE: In observational studies, type 2 diabetes mellitus (T2D) has been associated with an increased risk of hypertension, and vice versa; however, the causality between these conditions remains to be determined. OBJECTIVES: This population-based prospective cohort study sought to investigate the bidirectional causal relations of T2D with hypertension, systolic and diastolic blood pressure (BP) using Mendelian randomization (MR) analysis. METHODS AND RESULTS: After exclusion of participants free of a history of heart failure, cardiovascular disease, cardiac procedures, and non-T2D diabetes mellitus, a total of 318 664 unrelated individuals with qualified genotyping data of European descent aged 37 to 73 from UK Biobank were included. The genetically instrumented T2D and hypertension were constructed using 134 and 233 single nucleotide polymorphisms, respectively. Seven complementary MR methods were applied, including inverse-variance weighted method, 2 median-based methods (simple and weighted), MR-Egger, MR-robust adjusted profile scores, MR-Pleiotropy Residual Sum and Outlier, and multivariate MR. The genetically instrumented T2D was associated with risk of hypertension (odds ratio, 1.07 [95% CI, 1.04-1.10], P=3.4×10-7), whereas the genetically determined hypertension showed no relationship with T2D (odds ratio, 0.96 [0.88-1.04], P=0.34). Our MR estimates from T2D to BP showed that the genetically instrumented T2D was associated with a 0.67 mm Hg higher systolic BP (95% CI, 0.41-0.93, P=5.75×10-7) but not with a higher diastolic BP. There was no clear evidence showing a causal effect of elevated systolic BP or diastolic BP on T2D risk. Positive pleiotropic bias was indicated in the hypertension→T2D relation (odds ratio, of MR-Egger intercept 1.010 [1.004-1.016], P=0.001) but not from T2D to hypertension (1.001 [0.998-1.004], P=0.556). CONCLUSIONS: T2D may causally affect hypertension, whereas the relationship from hypertension to T2D is unlikely to be causal. These findings suggest the importance of keeping an optimal glycemic profile in general populations, and BP screening and monitoring, especially systolic BP, in patients with T2D.

Distinct genetic subtypes of adiposity and glycemic changes in response to weight-loss diet intervention: the POUNDS Lost trial.

PURPOSE: Obesity is a heterogeneous condition and distinct adiposity subtypes may differentially affect type 2 diabetes risk. We assessed relations between genetically determined subtypes of adiposity and changes in glycemic traits in a dietary intervention trial. METHODS: The four genetic subtypes of adiposity including waist-hip ratio-increase only (WHRonly+), body mass index-increase only (BMIonly+), WHR-increase and BMI-increase (BMI+WHR+), and WHR-decrease and BMI-increase (BMI+WHR-) were assessed by polygenetic scores (PGSs), calculated based on 159 single nucleotide polymorphisms related to BMI and/or WHR. We examined the associations between the four PGSs and changes in fasting glucose, insulin, ß-cell function (HOMA-B) and insulin resistance (HOMA-IR) in 692 overweight participants (84% white Americans) who were randomly assigned to one of four weight-loss diets in a 2-year intervention trial. RESULTS: Higher BMI+WHR-PGS was associated with a greater decrease in 2-year changes in waist circumference in white participants (P = 0.002). We also found significant interactions between WHRonly+PGS and dietary protein in 2-year changes in fasting glucose and HOMA-B (P = 0.0007 and < 0.0001, respectively). When consuming an average-protein diet, participants with higher WHRonly+PGS showed less increased fasting glucose (ß = - 0.46, P = 0.006) and less reduction in HOMA-B (ß = 0.02, P = 0.005) compared with lower WHRonly+PGS. Conversely, eating high-protein diet was associated with less decreased HOMA-B among individuals with lower than higher WHRonly+PGS (ß = - 0.02, P = 0.006). CONCLUSIONS: Distinct genetically determined adiposity subtypes may differentially modify the effects of weight-loss diets on improving glucose metabolism in white Americans. This trial was registered at clinicaltrials.gov as NCT00072995.