Metabolic phenotyping for discovery of urinary biomarkers of diet, xenobiotics and blood pressure in the INTERMAP Study: an overview

The etiopathogenesis of cardiovascular diseases (CVDs) is multifactorial. Adverse blood pressure (BP) is a major independent risk factor for epidemic CVD affecting ~40% of the adult population worldwide and resulting in significant morbidity and mortality. Metabolic phenotyping of biological fluids has proven its application in characterizing low-molecular-weight metabolites providing novel insights into gene-environmental-gut microbiome interaction in relation to a disease state. In this review, we synthesize key results from the INTERnational study of MAcro/micronutrients and blood Pressure (INTERMAP) Study, a cross-sectional epidemiologic study of 4680 men and women aged 40-59 years from Japan, the People's Republic of China, the United Kingdom and the United States. We describe the advancements we have made regarding the following: (1) analytical techniques for high-throughput metabolic phenotyping; (2) statistical analyses for biomarker identification; (3) discovery of unique food-specific biomarkers; and (4) application of metabolome-wide association studies to gain a better understanding into the molecular mechanisms of cross-cultural and regional BP differences

Common variants in SOX-2 and congenital cataract genes contribute to age-related nuclear cataract

Nuclear cataract is the most common type of age-related cataract and a leading cause of blindness worldwide. Age-related nuclear cataract is heritable (h2 = 0.48), but little is known about specific genetic factors underlying this condition. Here we report findings from the largest to date multi-ethnic meta-analysis of genome-wide association studies (discovery cohort N = 14,151 and replication N = 5299) of the International Cataract Genetics Consortium. We confirmed the known genetic association of CRYAA (rs7278468, P = 2.8 × 10−16) with nuclear cataract and identified five new loci associated with this disease: SOX2-OT (rs9842371, P = 1.7 × 1

Divergent survival outcomes associated with elevated branched-chain amino acid levels among older adults with or without hypertension and aiabetes:a validated, prospective, longitudinal follow-up study

Abstract Branched-chain amino acids are critical metabolic intermediates that can indicate increased risk of cardiometabolic disease when levels are elevated or, alternatively, suggest sufficient mitochondrial energy metabolism and reserve in old age. The interpretation of BCAA levels can be context-dependent, and it remains unclear whether abnormal levels can inform prognosis. This prospective longitudinal study aimed to determine the interrelationship between mortality hazard and fasting serum BCAA levels among older men and women aged ≥65 years with or without hypertension and diabetes mellitus. At baseline (0Y), fasting serum BCAA concentration in 2997 community-living older men and women were measured. Approximately 14 years later (14Y), 860 study participants returned for repeat measurements. Deaths were analysed and classified into cardiovascular and non-cardiovascular causes using International Classification of Diseases codes. Survival analysis and multivariable Cox regression were performed. During a median follow-up of 17Y, 971 (78.6%) non-cardiovascular and 263 (21.4%) cardiovascular deaths occurred among 1235 (41.2%) deceased (median age, 85.8 years [IQR 81.7–89.7]). From 0Y to 14Y, BCAA levels declined in both sexes, whereas serum creatinine concentration increased (both p < 0.0001). In older adults without hypertension or diabetes mellitus, the relationship between mortality hazard and BCAA level was linear and above-median BCAA levels were associated with improved survival, whereas in the presence of cardiometabolic disease the relationship was U-shaped. Overall, adjusted Cox regression determined that each 10% increment in BCAA concentration was associated with a 7% (p = 0.0002) and 16% (p = 0.0057) reduction in mortality hazard estimated at 0Y and 14Y, respectively. Our findings suggested that abnormally high or low (dyshomeostatic) BCAA levels among older adults with hypertension and/or diabetes mellitus were associated with increased mortality, whereas in those with neither disease, increased BCAA levels was associated with improved survival, particularly in the oldest-old

Characterising frailty, metrics of continuous glucose monitoring, and mortality hazards in older adults with type 2 diabetes on insulin therapy (HARE):a prospective, observational cohort study

Summary Background: To our knowledge, no previous study has examined the inter-relationship between frailty, dysglycaemia, and mortality in frail older adults with type 2 diabetes who are on insulin therapy. We used continuous glucose monitors (CGMs) to profile this patient population and determine the prognostic value of CGM metrics. We hypothesised that incremental frailty was associated with increased hypoglycaemia or time below range (TBR). Methods: HARE was a multicentre, prospective, observational cohort study with mortality hazard analysis carried out in four hospitals in Hong Kong. Eligible participants were community-living adults aged 70 years and older; had had type 2 diabetes for 5 years or more; were on insulin therapy; were frail; and were not hospitalised at the time of frailty assessment and CGM recording. Glucose control was characterised according to the Advanced Technologies and Treatments for Diabetes 2019 international consensus clinical targets. Frailty index was computed, and comprehensive frailty assessments and targeted serum metabolic profiling were performed. The Jonckheere-Terpstra test for trend was used to analyse frailty index tertiles and variables. Inter-relationships between CGM metrics and frailty, glycated haemoglobin A1c (HbA1c), and serum albumin were characterised using adjusted regression models. Survival analysis and Cox proportional hazard modelling were performed. Findings: Between July 25, 2018, and Sept 27, 2019, 225 participants were recruited, 222 of whom had CGMs fitted and 215 of whom had analysable CGM data (190 were frail, 25 were not frail). Incremental frailty was associated with older age, greater HbA1c, worse renal function, and history of stroke. Eight of 11 CGM metrics were significantly associated with frailty. Decreased time in range (TIR; glucose concentration 3·9–10·0 mmol/L) and increased time above range (TAR) metrics were strongly correlated with increased frailty and hyperglycaemia, whereas TBR metrics were marginally or not different between frailty levels. Glucose-lowering agents did not significantly affect regression estimates. In patients with HbA1c of 7·5% or more, reduced serum albumin was associated with level 2 TAR (glucose concentration >13·9 mmol/L) and dysglycaemia. During a median follow-up of 28·0 months (IQR 25·3–30·4), increased level 2 TAR was predictive of mortality explainable by frailty in the absence of detectable interaction. Each 1% increment of level 2 TAR was associated with 1·9% increase in mortality hazard. Interpretation: In older adults with type 2 diabetes who are on insulin therapy, incremental frailty was associated with increased dysglycaemia and hyperglycaemia rather than hypoglycaemia. Mortality hazard was increased with severe hyperglycaemia. Future clinical studies and trials targeting actionable CGM metrics highlighted in this study could translate into improved care and outcomes. Funding: Health and Medical Research Fund, Food and Health Bureau, The Government of the Hong Kong Special Administrative Region of China

Worldwide trends in blood pressure from 1975 to 2015:a pooled analysis of 1479 population-based measurement studies with 19.1 million participants

Abstract Background: Raised blood pressure is an important risk factor for cardiovascular diseases and chronic kidney disease. We estimated worldwide trends in mean systolic and mean diastolic blood pressure, and the prevalence of, and number of people with, raised blood pressure, defined as systolic blood pressure of 140 mm Hg or higher or diastolic blood pressure of 90 mm Hg or higher. Methods: For this analysis, we pooled national, subnational, or community population-based studies that had measured blood pressure in adults aged 18 years and older. We used a Bayesian hierarchical model to estimate trends from 1975 to 2015 in mean systolic and mean diastolic blood pressure, and the prevalence of raised blood pressure for 200 countries. We calculated the contributions of changes in prevalence versus population growth and ageing to the increase in the number of adults with raised blood pressure. Findings: We pooled 1479 studies that had measured the blood pressures of 19.1 million adults. Global age-standardised mean systolic blood pressure in 2015 was 127.0 mm Hg (95% credible interval 125.7–128.3) in men and 122.3 mm Hg (121.0–123.6) in women; age-standardised mean diastolic blood pressure was 78.7 mm Hg (77.9–79.5) for men and 76.7 mm Hg (75.9–77.6) for women. Global age-standardised prevalence of raised blood pressure was 24.1% (21.4–27.1) in men and 20.1% (17.8–22.5) in women in 2015. Mean systolic and mean diastolic blood pressure decreased substantially from 1975 to 2015 in high-income western and Asia Pacific countries, moving these countries from having some of the highest worldwide blood pressure in 1975 to the lowest in 2015. Mean blood pressure also decreased in women in central and eastern Europe, Latin America and the Caribbean, and, more recently, central Asia, Middle East, and north Africa, but the estimated trends in these super-regions had larger uncertainty than in high-income super-regions. By contrast, mean blood pressure might have increased in east and southeast Asia, south Asia, Oceania, and sub-Saharan Africa. In 2015, central and eastern Europe, sub-Saharan Africa, and south Asia had the highest blood pressure levels. Prevalence of raised blood pressure decreased in high-income and some middle-income countries; it remained unchanged elsewhere. The number of adults with raised blood pressure increased from 594 million in 1975 to 1.13 billion in 2015, with the increase largely in low-income and middle-income countries. The global increase in the number of adults with raised blood pressure is a net effect of increase due to population growth and ageing, and decrease due to declining age-specific prevalence. Interpretation: During the past four decades, the highest worldwide blood pressure levels have shifted from high-income countries to low-income countries in south Asia and sub-Saharan Africa due to opposite trends, while blood pressure has been persistently high in central and eastern Europe