Proteomic aging clock (PAC) predicts age-related outcomes in middle-aged and older adults

Beyond mere prognostication, optimal biomarkers of aging provide insights into qualitative and quantitative features of biological aging and might, therefore, offer useful information for the testing and, ultimately, clinical use of gerotherapeutics. We aimed to develop a proteomic aging clock (PAC) for all-cause mortality risk as a proxy of biological age. Data were from the UK Biobank Pharma Proteomics Project, including 53,021 participants aged between 39 and 70 years and 2,923 plasma proteins assessed using the Olink Explore 3072 assay®. The Spearman correlation between PAC proteomic age and chronological age was 0.77. A total of 10.9% of the participants died during a mean follow-up of 13.3 years, with the mean age at death 70.1 years. We developed a proteomic aging clock (PAC) for all-cause mortality risk as a surrogate of BA using a combination of least absolute shrinkage and selection operator (LASSO) penalized Cox regression and Gompertz proportional hazards models. PAC showed robust age-adjusted associations and predictions for all-cause mortality and the onset of various diseases in general and disease-free participants. The proteins associated with PAC were enriched in several processes related to the hallmarks of biological aging. Our results expand previous findings by showing that age acceleration, based on PAC, strongly predicts all-cause mortality and several incident disease outcomes. Particularly, it facilitates the evaluation of risk for multiple conditions in a disease-free population, thereby, contributing to the prevention of initial diseases, which vary among individuals and may subsequently lead to additional comorbidities.

Iron and risk of dementia: Mendelian randomisation analysis in UK Biobank

BACKGROUND

Brain iron deposition is common in dementia, but whether serum iron is a causal risk factor is unknown. We aimed to determine whether genetic predisposition to higher serum iron status biomarkers increased risk of dementia and atrophy of grey matter.

METHODS

We analysed UK Biobank participants clustered into European (N=451284), African (N=7477) and South Asian (N=9570) groups by genetic similarity to the 1000 genomes project. Using Mendelian randomisation methods, we estimated the association between genetically predicted serum iron (transferrin saturation [TSAT] and ferritin), grey matter volume and genetic liability to clinically defined dementia (including Alzheimer's disease [AD], non-AD dementia, and vascular dementia) from hospital and primary care records. We also performed time-to-event (competing risks) analysis of the TSAT polygenic score on risk of clinically defined non-AD dementia.

RESULTS

In Europeans, higher genetically predicted TSAT increased genetic liability to dementia (Odds Ratio [OR]: 1.15, 95% Confidence Intervals [CI] 1.04 to 1.26, p=0.0051), non-AD dementia (OR: 1.27, 95% CI 1.12 to 1.45, p=0.00018) and vascular dementia (OR: 1.37, 95% CI 1.12 to 1.69, p=0.0023), but not AD (OR: 1.00, 95% CI 0.86 to 1.15, p=0.97). Higher TSAT was also associated with increased risk of non-AD dementia in participants of African, but not South Asian groups. In survival analysis using a TSAT polygenic score, the effect was independent of apolipoprotein-E ε4 genotype (with adjustment subdistribution Hazard Ratio: 1.74, 95% CI 1.33 to 2.28, p=0.00006). Genetically predicted TSAT was associated with lower grey matter volume in caudate, putamen and thalamus, and not in other areas of interest.

DISCUSSION

Genetic evidence supports a causal relationship between higher TSAT and risk of clinically defined non-AD and vascular dementia, in European and African groups. This association appears to be independent of apolipoprotein-E ε4.

Is Mitochondrial DNA Copy Number from Human Blood Associated with Iron Deposits in the Brain?

Iron overload is implicated in mitochondrial dysfunction. Some iron and mitochondria-related measures show sex differences. It is unclear whether mitochondrial DNA copy number (mtDNAcn) from blood associated with iron depositions in the brain or liver and whether the relationship differs by sex. In this population-based study, we find that among community-dwelling adults, lower mtDNAcn assessed in blood is associated with higher brain iron in basal ganglia and hippocampus and more liver fat, and not with brain volumes or liver iron. Interestingly, the association between mtDNAcn and brain iron in basal ganglia is prominent in men. Our observations lead to the hypothesis that mechanisms connecting mitochondrial dysfunction and iron overload may differ between brain and liver and differ by sex.

Sarcopenic Obesity and Cardiometabolic Health and Mortality in Older Adults: a Growing Health Concern in an Ageing Population

PURPOSE OF REVIEW

Sarcopenic obesity (SO) is a growing public health problem in older adults. Whether SO confers higher risk of cardiometabolic disease and mortality than obesity or sarcopenia alone is still a matter of debate. We focus on recent findings on SO and cardiometabolic health and mortality in older adults.

RECENT FINDINGS

SO is associated with increased mortality compared to non-sarcopenic obesity, but similar mortality risk compared to sarcopenia without obesity. SO is associated with a higher risk of cardiovascular disease (CVD), diabetes, and physical disability than obesity or sarcopenia alone. SO, in the presence of diabetes, is associated with the highest risk of CVD and chronic kidney disease. A definition and diagnostic criteria for SO has recently been proposed (ESPEN and EASO). SO is associated with more adverse outcomes overall than sarcopenia or obesity alone. Future research is required to assess the impact of the new SO definition on health outcomes.

Hemochromatosis Genetic Variants and Musculoskeletal Outcomes: 11.5-Year Follow-Up in the UK Biobank Cohort Study

The iron overload disorder hemochromatosis is primarily caused by the homozygous HFE p.C282Y variant, but the scale of excess related musculoskeletal morbidity is uncertain. We estimated hemochromatosis-genotype associations with clinically diagnosed musculoskeletal outcomes and joint replacement surgeries in the UK Biobank community cohort. A total of 451,143 European ancestry participants (40 to 70 years at baseline) were followed in hospital records (mean 11.5-years). Cox proportional hazards models estimated HFE p.C282Y and p.H63D associations with incident outcomes. Male p.C282Y homozygotes (n = 1294) had increased incidence of osteoarthritis (n = 52, hazard ratio [HR]: 2.12 [95% confidence interval, CI: 1.61 to 2.80]; p = 8.8 × 10-8), hip replacement (n = 88, HR: 1.84 [95% CI: 1.49 to 2.27]; p = 1.6 × 10-8), knee replacement (n = 61, HR: 1.54 [95% CI: 1.20 to 1.98]; p = 8.4 × 10-4), and ankle and shoulder replacement, compared to males with no HFE mutations. Cumulative incidence analysis, using Kaplan-Meier lifetable probabilities demonstrated 10.4% of male homozygotes were projected to develop osteoarthritis and 15.5% to have hip replacements by age 75, versus 5.0% and 8.7% respectively without mutations. Male p.C282Y homozygotes also had increased incidence of femoral fractures (n = 15, HR: 1.72 [95% CI: 1.03 to 2.87]; p = 0.04) and osteoporosis (n = 21, HR: 1.71 [95% CI: 1.11 to 2.64]; p = 0.02), although the latter association was limited to those with liver fibrosis/cirrhosis diagnoses. Female p.C282Y homozygotes had increased incidence of osteoarthritis only (n = 57, HR: 1.46, [95% CI: 1.12 to 1.89]; p = 0.01). Male p.C282Y/p.H63D compound heterozygotes experienced a modest increased risk of hip replacements (n = 234, HR: 1.17 [95% CI: 1.02 to 1.33], p = 0.02), but this did not pass multiple testing corrections. In this large community cohort, the p.C282Y homozygote genotype was associated with substantial excess musculoskeletal morbidity in males. Wider HFE genotype testing may be justified, including in orthopedic clinics serving higher HFE variant prevalence populations. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Genetic modifiers of penetrance to liver endpoints in HFE hemochromatosis: Associations in a large community cohort

BACKGROUND

The iron overload condition hereditary hemochromatosis (HH) can cause liver cirrhosis and cancer, diabetes, and arthritis. Males homozygous for the p.C282Y missense mutation in the Homeostatin Iron Regulator (HFE) gene have greatest risk; yet, only a minority develop these conditions. We aimed to determine whether common genetic variants influencing iron levels or liver disease risk in the general population also modify clinical penetrance in HFE p.C282Y and p.H63D carriers.

METHODS

We studied 1294 male and 1596 female UK Biobank HFE p.C282Y homozygous participants of European ancestry with medical records up to 14 years after baseline assessment. Polygenic scores quantified genetic effects of blood iron biomarkers and relevant diseases (identified in the general population). Analyses were also performed in other HFE p.C282Y/p.H63D genotype groups.

RESULTS

In male p.C282Y homozygotes, a higher iron polygenic score increased the risk of liver fibrosis or cirrhosis diagnoses (odds ratio for the top 20% of iron polygenic score vs. the bottom 20% = 4.90: 95% confidence intervals, 1.63-14.73; p = 0.005), liver cancer, and osteoarthritis but not diabetes. A liver cirrhosis polygenic score was associated with liver cancer diagnoses. In female p.C282Y homozygotes, the osteoarthritis polygenic score was associated with increased osteoarthritis diagnoses and type-2 diabetes polygenic score with diabetes. However, the iron polygenic score was not robustly associated with diagnoses in p.C282Y female homozygotes or in other p.C282Y/p.H63D genotypes.

CONCLUSIONS

HFE p.C282Y homozygote penetrance to clinical disease in a large community cohort was partly explained by common genetic variants that influence iron and risks of related diagnoses in the general population, including polygenic scores in HH screening and diagnosis, may help in estimating prognosis and treatment planning.

Hereditary Hemochromatosis Variant Associations with Incident Nonliver Malignancies: 11-Year Follow-up in UK Biobank

BACKGROUND

In European ancestry populations, iron overload disorder hereditary hemochromatosis is predominantly caused by HFE p.C282Y and p.H63D mutations. Male p.C282Y homozygotes have markedly increased hepatic malignancy incidence, but risks for other cancers in male and female homozygotes are unclear.

METHODS

451,143 UK Biobank European ancestry participants (aged 40-70 years; 54.3% female) were followed (mean 11.6 years) via hospital admissions and national cancer registries. We estimated risks of any incident cancer (other than nonmelanoma and liver cancer) and common incident cancers [bladder, blood (with subanalyses of leukemia and lymphoma), bone, brain, breast, colorectal, kidney, lung, melanoma, esophageal, ovarian, pancreatic, prostate and stomach] in those with p.C282Y and p.H63D genotypes, compared with participants without HFE mutations.

RESULTS

Male p.C282Y homozygotes (n = 2,890, 12.1% with baseline diagnosed hereditary hemochromatosis) had increased incidence of prostate cancer [6.8% vs. 5.4% without mutations; HR = 1.32; 95% confidence interval (CI), 1.07-1.63; P = 0.01; Bonferroni adjusted P = 0.17] during follow-up. In life table estimates from ages 40 to 75 years, 14.4% of male p.C282Y homozygotes are projected to develop prostate cancer (versus 10.7% without mutations, excess 3.8%; 95% CI, 1.3-6.8). No increases in risks were found for other studied cancers in male or female p.C282Y homozygotes, or in any other p.C282Y/p.H63D genotype groups of either sex.

CONCLUSIONS

In a large community sample of male p.C282Y homozygotes, there is suggestive evidence of increased prostate cancer incidence, with no evidence of excess of other studied (nonliver) cancers.

IMPACT

Replication of results in other large community genotyped cohorts are needed to confirm if clinical monitoring for prostate cancer is necessary in p.C282Y homozygous males.

Analysis of CYP2C19 genetic variants with ischaemic events in UK patients prescribed clopidogrel in primary care: a retrospective cohort study

OBJECTIVE

To determine whether CYP2C19 loss-of-function (LoF) alleles increase risk of ischaemic stroke and myocardial infarction (MI) in UK primary care patients prescribed clopidogrel.

DESIGN

Retrospective cohort analysis.

SETTING

Primary care practices in the UK from January 1999 to September 2017.

PARTICIPANTS

7483 European-ancestry adults from the UK Biobank study with genetic and linked primary care data, aged 36-79 years at time of first clopidogrel prescription.

INTERVENTIONS

Clopidogrel prescription in primary care, mean duration 2.6 years (range 2 months to 18 years).

MAIN OUTCOME MEASURE

Hospital inpatient-diagnosed ischaemic stroke, MI or angina while treated with clopidogrel.

RESULTS

28.7% of participants carried at least one CYP2C19 LoF variant. LoF carriers had higher rates of incident ischaemic stroke while treated with clopidogrel compared with those without the variants (8 per 1000 person-years vs 5.2 per 1000 person-years; HR 1.53, 95% CIs 1.04 to 2.26, p=0.031). LoF carriers also had increased risk of MI (HR 1.14, 95% CI 1.04 to 1.26, p=0.008). In combined analysis LoF carriers had increased risk of any ischaemic event (stroke or MI) (HR 1.17, 95% CI 1.06 to 1.29, p=0.002). Adjustment for aspirin coprescription produced similar estimates. In lifetables using observed incidence rates, 22.5% (95% CI 14.4% to 34.0%) of CYP2C19 LoF carriers on clopidogrel were projected to develop an ischaemic stroke by age 79 (oldest age in the study), compared with 15.4% (95% CI 11.4% to 20.5%) in non-carriers, that is, 7.1% excess stroke incidence in LoF carriers by age 79.

CONCLUSIONS

A substantial proportion of the UK population carry genetic variants that reduce metabolism of clopidogrel to its active form. In family practice patients on clopidogrel, CYP2C19 LoF variants are associated with substantially higher incidence of ischaemic events. Genotype-guided selection of antiplatelet medications may improve outcomes in patients carrying CYP2C19 genetic variants.

Hemochromatosis Mutations, Brain Iron Imaging, and Dementia in the UK Biobank Cohort

Background:

Brain iron deposition occurs in dementia. In European ancestry populations, the HFE p.C282Y variant can cause iron overload and hemochromatosis, mostly in homozygous males.

Objective:

To estimate p.C282Y associations with brain MRI features plus incident dementia diagnoses during follow-up in a large community cohort.

Methods:

UK Biobank participants with follow-up hospitalization records (mean 10.5 years). MRI in 206 p.C282Y homozygotes versus 23,349 without variants, including T2^* measures (lower values indicating more iron).

Results:

European ancestry participants included 2,890 p.C282Y homozygotes. Male p.C282Y homozygotes had lower T2^* measures in areas including the putamen, thalamus, and hippocampus, compared to no HFE mutations. Incident dementia was more common in p.C282Y homozygous men (Hazard Ratio HR = 1.83; 95% CI 1.23 to 2.72, p = 0.003), as was delirium. There were no associations in homozygote women or in heterozygotes.

Conclusion:

Studies are needed of whether early iron reduction prevents or slows related brain pathologies in male HFE p.C282Y homozygotes.

A genome-wide association study of the frailty index highlights brain pathways in ageing

Frailty is a common geriatric syndrome and strongly associated with disability, mortality and hospitalization. Frailty is commonly measured using the frailty index (FI), based on the accumulation of a number of health deficits during the life course. The mechanisms underlying FI are multifactorial and not well understood, but a genetic basis has been suggested with heritability estimates between 30 and 45%. Understanding the genetic determinants and biological mechanisms underpinning FI may help to delay or even prevent frailty. We performed a genome-wide association study (GWAS) meta-analysis of a frailty index in European descent UK Biobank participants (n = 164,610, 60-70 years) and Swedish TwinGene participants (n = 10,616, 41-87 years). FI calculation was based on 49 or 44 self-reported items on symptoms, disabilities and diagnosed diseases for UK Biobank and TwinGene, respectively. 14 loci were associated with the FI (p < 5*10-8 ). Many FI-associated loci have established associations with traits such as body mass index, cardiovascular disease, smoking, HLA proteins, depression and neuroticism; however, one appears to be novel. The estimated single nucleotide polymorphism (SNP) heritability of the FI was 11% (0.11, SE 0.005). In enrichment analysis, genes expressed in the frontal cortex and hippocampus were significantly downregulated (adjusted p < 0.05). We also used Mendelian randomization to identify modifiable traits and exposures that may affect frailty risk, with a higher educational attainment genetic risk score being associated with a lower degree of frailty. Risk of frailty is influenced by many genetic factors, including well-known disease risk factors and mental health, with particular emphasis on pathways in the brain.

Biological Aging Predicts Vulnerability to COVID-19 Severity in UK Biobank Participants

Background

Age and disease prevalence are the 2 biggest risk factors for Coronavirus disease 2019 (COVID-19) symptom severity and death. We therefore hypothesized that increased biological age, beyond chronological age, may be driving disease-related trends in COVID-19 severity.

Methods

Using the UK Biobank England data, we tested whether a biological age estimate (PhenoAge) measured more than a decade prior to the COVID-19 pandemic was predictive of 2 COVID-19 severity outcomes (inpatient test positivity and COVID-19-related mortality with inpatient test-confirmed COVID-19). Logistic regression models were used with adjustment for age at the pandemic, sex, ethnicity, baseline assessment centers, and preexisting diseases/conditions.

Results

Six hundred and thirteen participants tested positive at inpatient settings between March 16 and April 27, 2020, 154 of whom succumbed to COVID-19. PhenoAge was associated with increased risks of inpatient test positivity and COVID-19-related mortality (OR_Mortality = 1.63 per 5 years, 95% CI: 1.43–1.86, p = 4.7 × 10⁻¹³) adjusting for demographics including age at the pandemic. Further adjustment for preexisting diseases/conditions at baseline (OR_M = 1.50, 95% CI: 1.30–1.73 per 5 years, p = 3.1 × 10⁻⁸) and at the early pandemic (OR_M = 1.21, 95% CI: 1.04–1.40 per 5 years, p = .011) decreased the association.

Conclusions

PhenoAge measured in 2006–2010 was associated with COVID-19 severity outcomes more than 10 years later. These associations were partly accounted for by prevalent chronic diseases proximate to COVID-19 infection. Overall, our results suggest that aging biomarkers, like PhenoAge may capture long-term vulnerability to diseases like COVID-19, even before the accumulation of age-related comorbid conditions.

Nutrition and Frailty: Opportunities for Prevention and Treatment

Frailty is a syndrome of growing importance given the global ageing population. While frailty is a multifactorial process, poor nutritional status is considered a key contributor to its pathophysiology. As nutrition is a modifiable risk factor for frailty, strategies to prevent and treat frailty should consider dietary change. Observational evidence linking nutrition with frailty appears most robust for dietary quality: for example, dietary patterns such as the Mediterranean diet appear to be protective. In addition, research on specific foods, such as a higher consumption of fruit and vegetables and lower consumption of ultra-processed foods are consistent, with healthier profiles linked to lower frailty risk. Few dietary intervention studies have been conducted to date, although a growing number of trials that combine supplementation with exercise training suggest a multi-domain approach may be more effective. This review is based on an interdisciplinary workshop, held in November 2020, and synthesises current understanding of dietary influences on frailty, focusing on opportunities for prevention and treatment. Longer term prospective studies and well-designed trials are needed to determine the causal effects of nutrition on frailty risk and progression and how dietary change can be used to prevent and/or treat frailty in the future.

Genetic associations for two biological age measures point to distinct aging phenotypes

Biological age measures outperform chronological age in predicting various aging outcomes, yet little is known regarding genetic predisposition. We performed genome-wide association scans of two age-adjusted biological age measures (PhenoAgeAcceleration and BioAgeAcceleration), estimated from clinical biochemistry markers (Levine et al., 2018; Levine, 2013) in European-descent participants from UK Biobank. The strongest signals were found in the APOE gene, tagged by the two major protein-coding SNPs, PhenoAgeAccel-rs429358 (APOE e4 determinant) (p = 1.50 × 10-72 ); BioAgeAccel-rs7412 (APOE e2 determinant) (p = 3.16 × 10-60 ). Interestingly, we observed inverse APOE e2 and e4 associations and unique pathway enrichments when comparing the two biological age measures. Genes associated with BioAgeAccel were enriched in lipid related pathways, while genes associated with PhenoAgeAccel showed enrichment for immune system, cell function, and carbohydrate homeostasis pathways, suggesting the two measures capture different aging domains. Our study reaffirms that aging patterns are heterogeneous across individuals, and the manner in which a person ages may be partly attributed to genetic predisposition.

Genome-wide meta-analysis of muscle weakness identifies 15 susceptibility loci in older men and women

Low muscle strength is an important heritable indicator of poor health linked to morbidity and mortality in older people. In a genome-wide association study meta-analysis of 256,523 Europeans aged 60 years and over from 22 cohorts we identify 15 loci associated with muscle weakness (European Working Group on Sarcopenia in Older People definition: n = 48,596 cases, 18.9% of total), including 12 loci not implicated in previous analyses of continuous measures of grip strength. Loci include genes reportedly involved in autoimmune disease (HLA-DQA1 p = 4 × 10-17), arthritis (GDF5 p = 4 × 10-13), cell cycle control and cancer protection, regulation of transcription, and others involved in the development and maintenance of the musculoskeletal system. Using Mendelian randomization we report possible overlapping causal pathways, including diabetes susceptibility, haematological parameters, and the immune system. We conclude that muscle weakness in older adults has distinct mechanisms from continuous strength, including several pathways considered to be hallmarks of ageing.

Association of Hemochromatosis HFE p.C282Y Homozygosity With Hepatic Malignancy

IMPORTANCE

Hereditary hemochromatosis is predominantly caused by the HFE p.C282Y homozygous pathogenic variant. Liver carcinoma and mortality risks are increased in individuals with clinically diagnosed hereditary hemochromatosis, but risks are unclear in mostly undiagnosed p.C282Y homozygotes identified in community genotyping.

OBJECTIVE

To estimate the incidence of primary hepatic carcinoma and death by HFE variant status.

DESIGN, SETTING, AND PARTICIPANTS

Cohort study of 451 186 UK Biobank participants of European ancestry (aged 40-70 years), followed up from baseline assessment (2006-2010) until January 2018.

EXPOSURES

Men and women with HFE p.C282Y and p.H63D genotypes compared with those with neither HFE variants.

MAIN OUTCOMES AND MEASURES

Two linked co-primary outcomes (incident primary liver carcinoma and death from any cause) were ascertained from follow-up via hospital inpatient records, national cancer registry, and death certificate records, and from primary care data among a subset of participants for whom data were available. Associations between genotype and outcomes were tested using Cox regression adjusted for age, assessment center, genotyping array, and population genetics substructure. Kaplan-Meier lifetable probabilities of incident diagnoses were estimated from age 40 to 75 years by HFE genotype and sex.

RESULTS

A total of 451 186 participants (mean [SD] age, 56.8 [8.0] years; 54.3% women) were followed up for a median (interquartile range) of 8.9 (8.3-9.5) years. Among the 1294 male p.C282Y homozygotes, there were 21 incident hepatic malignancies, 10 of which were in participants without a diagnosis of hemochromatosis at baseline. p.C282Y homozygous men had a higher risk of hepatic malignancies (hazard ratio [HR], 10.5 [95% CI, 6.6-16.7]; P < .001) and all-cause mortality (n = 88; HR, 1.2 [95% CI, 1.0-1.5]; P = .046) compared with men with neither HFE variant. In lifetables projections for male p.C282Y homozygotes to age 75 years, the risk of primary hepatic malignancy was 7.2% (95% CI, 3.9%-13.1%), compared with 0.6% (95% CI, 0.4%-0.7%) for men with neither variant, and the risk of death was 19.5% (95% CI, 15.8%-24.0%), compared with 15.1% (95% CI, 14.7%-15.5%) among men with neither variant. Among female p.C282Y homozygotes (n = 1596), there were 3 incident hepatic malignancies and 60 deaths, but the associations between homozygosity and hepatic malignancy (HR, 2.1 [95% CI, 0.7-6.5]; P = .22) and death (HR, 1.2 [95% CI, 0.9-1.5]; P = .20) were not statistically significant.

CONCLUSIONS AND RELEVANCE

Among men with HFE p.C282Y homozygosity, there was a significantly increased risk of incident primary hepatic malignancy and death compared with men without p.C282Y or p.H63D variants; there was not a significant association for women. Further research is needed to understand the effects of early diagnosis and treatment.

Preexisting Comorbidities Predicting COVID-19 and Mortality in the UK Biobank Community Cohort

BACKGROUND

Hospitalized COVID-19 patients tend to be older and frequently have hypertension, diabetes, or coronary heart disease, but whether these comorbidities are true risk factors (ie, more common than in the general older population) is unclear. We estimated associations between preexisting diagnoses and hospitalized COVID-19 alone or with mortality, in a large community cohort.

METHODS

UK Biobank (England) participants with baseline assessment 2006-2010, followed in hospital discharge records to 2017 and death records to 2020. Demographic and preexisting common diagnoses association tested with hospitalized laboratory-confirmed COVID-19 (March 16 to April 26, 2020), alone or with mortality, in logistic models.

RESULTS

Of 269 070 participants aged older than 65, 507 (0.2%) became COVID-19 hospital inpatients, of which 141 (27.8%) died. Common comorbidities in hospitalized inpatients were hypertension (59.6%), history of fall or fragility fractures (29.4%), coronary heart disease (21.5%), type 2 diabetes (type 2, 19. 9%), and asthma (17.6%). However, in models adjusted for comorbidities, age group, sex, ethnicity, and education, preexisting diagnoses of dementia, type 2 diabetes, chronic obstructive pulmonary disease, pneumonia, depression, atrial fibrillation, and hypertension emerged as independent risk factors for COVID-19 hospitalization, the first 5 remaining statistically significant for related mortality. Chronic kidney disease and asthma were risk factors for COVID-19 hospitalization in women but not men.

CONCLUSIONS

There are specific high-risk preexisting comorbidities for COVID-19 hospitalization and related deaths in community-based older men and women. These results do not support simple age-based targeting of the older population to prevent severe COVID-19 infections.

Low Vitamin D Levels and Risk of Incident Delirium in 351,000 Older UK Biobank Participants

BACKGROUND/OBJECTIVES

Delirium is common in older adults, especially following hospitalization. Because low vitamin D levels may be associated with increased delirium risk, we aimed to determine the prognostic value of blood vitamin D levels, extending our previous genetic analyses of this relationship.

DESIGN

Prospective cohort analysis.

SETTING

Community-based cohort study of adults from 22 cities across the United Kingdom (the UK Biobank).

PARTICIPANTS

Adults aged 60 and older by the end of follow-up in the linked hospital inpatient admissions data, up to 14 years after baseline (n = 351,320).

MEASUREMENTS

At baseline, serum vitamin D (25-OH-D) levels were measured. We used time-to-event models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between vitamin D deficiency and incident hospital-diagnosed delirium, adjusted for age, sex, assessment month, assessment center, and ethnicity. We performed Mendelian randomization genetic analysis in European participants to further investigate vitamin D and delirium risk.

RESULTS

A total of 3,634 (1.03%) participants had at least one incident hospital-diagnosed delirium episode. Vitamin D deficiency (<25 nmol/L) predicted a large incidence in delirium (HR = 2.49; 95% CI = 2.24-2.76; P = 3*10^-68 , compared with >50 nmol/L). Increased risk was not limited to the deficient group: insufficient levels (25-50 nmol/L) were also at increased risk (HR = 1.38; 95% CI = 1.28-1.49; P = 4*10^-18 ). The association was independent of calcium levels, hospital-diagnosed fractures, dementia, and other relevant cofactors. In genetic analysis, participants carrying more vitamin D-increasing variants had a reduced likelihood of incident delirium diagnosis (HR = .80 per standard deviation increase in genetically instrumented vitamin D: .73-.87; P = 2*10^-7 ).

CONCLUSION

Progressively lower vitamin D levels predicted increased risks of incident hospital-diagnosed delirium, and genetic evidence supports a shared causal pathway. Because low vitamin D levels are simple to detect and inexpensive and safe to correct, an intervention trial to confirm these results is urgently needed.

The relationship of parental longevity with the aging brain-results from UK Biobank

A few studies report that parental longevity is associated with preserved cognition and physical function and lower risk of Alzheimer's disease. However, data on structural neuroimaging correlates of parental longevity and its spatial distribution are limited. This study aims to examine relationships of parental longevity with regional brain structure and to explore sex differences. We identified 12,970 UK Biobank participants (mean age = 64.4, 51.5%women) with data on parental longevity, regional gray matter volumes, and white matter microstructure. Participants were categorized based on whether at least one parent lived to age 85 or older or neither parent survived to age 85. Associations of parental longevity, maternal, and paternal longevity with each neuroimaging marker of interest were examined using linear regression, adjusted for demographics, APOE e4 status, lifestyle, and cardiometabolic conditions. Compared to participants whose both parents died before 85 (43%), those with at least one parent surviving to 85 (57%) had greater volumes in hippocampus, parahippocampal gyrus, middle temporal lobe, and primary sensorimotor cortex and had lower mean diffusivity in posterior thalamic radiation and uncinate fasciculus. Associations were prominent with maternal longevity. Adjustment for cardiometabolic conditions did not affect observed associations except mean diffusivity in posterior thalamic radiation. There were no structural differences in other areas. Parental longevity is associated with preserved brain structure localized in primary sensorimotor cortex and temporal areas including hippocampus. These relationships are prominent with maternal longevity. Longitudinal studies are needed to determine whether changes in these brain structures account for the association between parental longevity and dementia.

Genetic associations for two biological age measures point to distinct aging phenotypes

Biological age measures outperform chronological age in predicting various aging outcomes, yet little is known regarding genetic predisposition. We performed genome-wide association scans of two age-adjusted biological age measures (PhenoAgeAcceleration and BioAgeAcceleration), estimated from clinical biochemistry markers ^1,2 in European-descent participants from UK Biobank. The strongest signals were found in the APOE gene, tagged by the two major protein-coding SNPs, PhenoAgeAccel-rs429358 (APOE e4 determinant) (p=1.50 × 10 ^-72 ); BioAgeAccel-rs7412 (APOE e2 determinant) (p=3.16 × 10 ^-60 ). Interestingly, we observed inverse APOE e2 and e4 associations and unique pathway enrichments when comparing the two biological age measures. Genes associated with BioAgeAccel were enriched in lipid related pathways, while genes associated with PhenoAgeAccel showed enrichment for immune system, cell function, and carbohydrate homeostasis pathways, suggesting the two measures capture different aging domains. Our study reaffirms that aging patterns are heterogenous across individuals, and the manner in which a person ages may be partly attributed to genetic predisposition.

COVID-19 severity is predicted by earlier evidence of accelerated aging

With no known treatments or vaccine, COVID-19 presents a major threat, particularly to older adults, who account for the majority of severe illness and deaths. The age-related susceptibility is partly explained by increased comorbidities including dementia and type II diabetes [1]. While it is unclear why these diseases predispose risk, we hypothesize that increased biological age, rather than chronological age, may be driving disease-related trends in COVID-19 severity with age. To test this hypothesis, we applied our previously validated biological age measure (PhenoAge) [2] composed of chronological age and nine clinical chemistry biomarkers to data of 347,751 participants from a large community cohort in the United Kingdom (UK Biobank), recruited between 2006 and 2010. Other data included disease diagnoses (to 2017), mortality data (to 2020), and the UK national COVID-19 test results (to May 31, 2020) [3]. Accelerated aging 10-14 years prior to the start of the COVID-19 pandemic was associated with test positivity (OR=1.15 per 5-year acceleration, 95% CI: 1.08 to 1.21, p=3.2×10-6) and all-cause mortality with test-confirmed COVID-19 (OR=1.25, per 5-year acceleration, 95% CI: 1.09 to 1.44, p=0.002) after adjustment for demographics including current chronological age and pre-existing diseases or conditions. The corresponding areas under the curves were 0.669 and 0.803, respectively. Biological aging, as captured by PhenoAge, is a better predictor of COVID-19 severity than chronological age, and may inform risk stratification initiatives, while also elucidating possible underlying mechanisms, particularly those related to inflammaging.

ApoE e2 and aging-related outcomes in 379,000 UK Biobank participants

The Apolipoprotein E (APOE) e4 allele is associated with reduced longevity and increased Coronary Artery Disease (CAD) and Alzheimer’s disease, with e4e4 having markedly larger effect sizes than e3e4. The e2 longevity promoting variant is less studied. We conducted a phenome-wide association study of ApoE e2e3 and e2e2 with aging phenotypes, to assess their potential as targets for anti-aging interventions. Data were from 379,000 UK Biobank participants, aged 40 to 70 years. e2e3 (n=46,535) had mostly lower lipid-related biomarker levels including reduced total and LDL-cholesterol, and lower risks of CAD (Odds Ratio=0.87, 95% CI: 0.83 to 0.90, p=4.92×10^-14) and hypertension (OR=0.94, 95% CI: 0.92 to 0.97, p=7.28×10^-7) versus e3e3. However, lipid changes in e2e2 (n=2,398) were more extreme, including a marked increase in triglyceride levels (0.41 Standard Deviations, 95% CI: 0.37 to 0.45, p=5.42×10^-92), with no associated changes in CAD risks. There were no associations with biomarkers of kidney function. The effects of both e2e2 and e2e3 were minimal on falls, muscle mass, grip strength or frailty. In conclusion, e2e3 has protective effects on some health outcomes, but the effects of e2e2 are not similar, complicating the potential usefulness of e2 as a target for anti-aging intervention.

Impact of Low Cardiovascular Risk Profiles on Geriatric Outcomes: Evidence From 421,000 Participants in Two Cohorts

BACKGROUND

Individuals with low cardiovascular risk factor profiles experience lower rates of cardiovascular diseases, but associations with geriatric syndromes are unclear. We tested whether individuals with low cardiovascular disease risk, aged 60-69 years old at baseline in two large cohorts, were less likely to develop aging-related adverse health outcomes.

METHODS

Data were from population representative medical records (Clinical Practice Research Datalink [CPRD] England, n = 239,591) and healthy volunteers (UK Biobank [UKB], n = 181,820), followed for ≤10 years. A cardiovascular disease risk score (CRS) summarized smoking status, LDL-cholesterol, blood pressure, body mass index, fasting glucose and physical activity, grouping individuals as low (ie, all factors near ideal), moderate, or high CRS. Logistic regression, Cox models, and Fine and Grey risk models tested the associations between the CRS and health outcomes.

RESULTS

Low CRS individuals had less chronic pain (UKB: baseline odds ratio = 0.52, confidence interval [CI] = 0.50-0.54), lower incidence of incontinence (CPRD: subhazard ratio [sub-HR] = 0.75, 0.63-0.91), falls (sub-HR = 0.82, CI = 0.73-0.91), fragility fractures (sub-HR = 0.78, CI = 0.65-0.93), and dementia (vs. high risks; UKB: sub-HR = 0.67, CI = 0.50-0.89; CPRD: sub-HR = 0.79, CI = 0.56-1.12). Only 5.4% in CPRD with low CRS became frail (Rockwood index) versus 24.2% with high CRS. All-cause mortality was markedly lower in the low CRS group (vs. high CRS; HR = 0.40, 95% CI = 0.35-0.47). All associations showed dose-response relationships, and results were similar in both cohorts.

CONCLUSIONS

Persons aged 60-69 years with near-ideal cardiovascular risk factor profiles have substantially lower incidence of geriatric conditions and frailty. Optimizing cardiovascular disease risk factors may substantially reduce the burden of morbidity in later life.

Physical frailty in older men: prospective associations with diet quality and patterns

BACKGROUND

increasing numbers of older adults are living with frailty and its adverse consequences. We investigated relationships between diet quality or patterns and incident physical frailty in older British men and whether any associations were influenced by inflammation.

METHODS

prospective study of 945 men from the British Regional Heart Study aged 70-92 years with no prevalent frailty. Incident frailty was assessed by questionnaire after 3 years of follow-up. Frailty was defined as having at least three of: low grip strength, low physical activity, slow walking speed, unintentional weight loss and feeling of low energy, all based on self-report. The Healthy Diet Indicator (HDI) based on WHO dietary guidelines and the Elderly Dietary Index (EDI) based on a Mediterranean-style dietary intake were computed from questionnaire data and three dietary patterns were identified using principal components analysis: prudent, high fat/low fibre and high sugar.

RESULTS

men in the highest EDI category and those who followed a prudent diet were less likely to become frail [top vs bottom category odds ratio (OR) (95% CI) 0.49 (0.30, 0.82) and 0.53 (0.30, 0.92) respectively] after adjustment for potential confounders including BMI and prevalent cardiovascular disease. No significant association was seen for the HDI. By contrast those who had a high fat low fibre diet pattern were more likely to become frail [OR (95% CI) 2.54 (1.46, 4.40)]. These associations were not mediated by C-reactive protein (marker of inflammation).

CONCLUSIONS

the findings suggest adherence to a Mediterranean-style diet is associated with reduced risk of developing frailty in older people.

Hereditary Hemochromatosis Associations with Frailty, Sarcopenia and Chronic Pain: Evidence from 200,975 Older UK Biobank Participants

BACKGROUND

Iron is essential for life but contributes to oxidative damage. In Northern-European ancestry populations, HFE gene C282Y mutations are relatively common (0.3%-0.6% rare homozygote prevalence) and associated with excessive iron absorption, fatigue, diabetes, arthritis, and liver disease, especially in men. Iron excess can be prevented or treated but diagnosis is often delayed or missed. Data on sarcopenia, pain, and frailty are scarce.

METHODS

Using 200,975 UK Biobank volunteers aged 60-70 years, we tested associations between C282Y homozygosity with Fried frailty, sarcopenia, and chronic pain using logistic regression adjusted for age and technical genetic covariates. As iron overload is progressive (with menstruation protective), we included specific analyses of older (65-70 years) females and males.

RESULTS

One thousand three hundred and twelve (0.65%) participants were C282Y homozygotes; 593 were men (0.62%) and 719 were women (0.68%). C282Y homozygote men had increased likelihoods of reporting chronic pain (odds ratio [OR] 1.23: 95% confidence interval [CI] 1.05-1.45, p = .01) and diagnoses of polymyalgia rheumatica, compared to common "wild-type" genotype. They were also more likely to have sarcopenia (OR 2.38: 1.80-3.13, p = 9.70 × 10-10) and frailty (OR 2.01: 1.45-2.80, p = 3.41 × 10-05). C282Y homozygote women (n = 312, 0.7%) aged 65-70 were more likely to be frail (OR 1.73: 1.05-2.84, p = .032) and have chronic knee, hip, and back pain. Overall, 1.50% of frail men and 1.51% of frail women in the 65-70 age group were C282Y homozygous.

CONCLUSIONS

HFE C282Y homozygosity is associated with substantial excess sarcopenia, frailty, and chronic pain at older ages. Given the availability of treatment, hereditary hemochromatosis is a strong candidate for precision medicine approaches to improve outcomes in late life.

Healthier diet quality and dietary patterns are associated with lower risk of mobility limitation in older men

Purpose

To investigate associations between diet quality, dietary patterns and mobility limitation 15 years later in a population-based sample of older British men.

Methods

We used longitudinal data from 1234 men from the British Regional Heart Study, mean age 66 years at baseline. Mobility limitation was defined as difficulty going up- or downstairs or walking 400 yards as a result of a long-term health problem. Dietary intake was measured using a food frequency questionnaire data from which the Healthy Diet Indicator (HDI), the Elderly Dietary Index (EDI), and three a posteriori dietary patterns were derived. The a posteriori dietary patterns were identified using principal components analysis: (1) high fat/low fibre, (2) prudent and (3) high sugar.

Results

Men with greater adherence to the EDI or HDI were less likely to have mobility limitation at follow-up, top vs bottom category odds ratio for the EDI OR 0.50, 95% CI 0.34, 0.75, and for the HDI OR 0.55, 95% CI 0.35, 0.85, after adjusting for age, social class, region of residence, smoking, alcohol consumption and energy intake. Men with a higher score for the high-fat/low-fibre pattern at baseline were more likely to have mobility limitation at follow-up, top vs bottom quartile odds ratio OR 3.28 95% CI 2.05, 5.24. These associations were little changed by adjusting for BMI and physical activity.

Conclusion

Our study provides evidence that healthier eating patterns could contribute to prevention or delay of mobility limitation in older British men.

Electronic supplementary material

The online version of this article (10.1007/s00394-018-1786-y) contains supplementary material, which is available to authorized users.

Red blood cell distribution width: Genetic evidence for aging pathways in 116,666 volunteers

INTRODUCTION

Variability in red blood cell volumes (distribution width, RDW) increases with age and is strongly predictive of mortality, incident coronary heart disease and cancer. We investigated inherited genetic variation associated with RDW in 116,666 UK Biobank human volunteers.

RESULTS

A large proportion RDW is explained by genetic variants (29%), especially in the older group (60+ year olds, 33.8%, <50 year olds, 28.4%). RDW was associated with 194 independent genetic signals; 71 are known for conditions including autoimmune disease, certain cancers, BMI, Alzheimer's disease, longevity, age at menopause, bone density, myositis, Parkinson's disease, and age-related macular degeneration. Exclusion of anemic participants did not affect the overall findings. Pathways analysis showed enrichment for telomere maintenance, ribosomal RNA, and apoptosis. The majority of RDW-associated signals were intronic (119 of 194), including SNP rs6602909 located in an intron of oncogene GAS6, an eQTL in whole blood.

CONCLUSIONS

Although increased RDW is predictive of cardiovascular outcomes, this was not explained by known CVD or related lipid genetic risks, and a RDW genetic score was not predictive of incident disease. The predictive value of RDW for a range of negative health outcomes may in part be due to variants influencing fundamental pathways of aging.

Central adiposity and the overweight risk paradox in aging: follow-up of 130,473 UK Biobank participants

Background: For older groups, being overweight [body mass index (BMI; in kg/m²): 25 to <30] is reportedly associated with a lower or similar risk of mortality than being normal weight (BMI: 18.5 to <25). However, this "risk paradox" is partly explained by smoking and disease-associated weight loss. This paradox may also arise from BMI failing to measure fat redistribution to a centralized position in later life.Objective: This study aimed to estimate associations between combined measurements of BMI and waist-to-hip ratio (WHR) with mortality and incident coronary artery disease (CAD).Design: This study followed 130,473 UK Biobank participants aged 60-69 y (baseline 2006-2010) for ≤8.3 y (n = 2974 deaths). Current smokers and individuals with recent or disease-associated (e.g., from dementia, heart failure, or cancer) weight loss were excluded, yielding a "healthier agers" group. Survival models were adjusted for age, sex, alcohol intake, smoking history, and educational attainment. Population and sex-specific lower and higher WHR tertiles were <0.91 and ≥0.96 for men and <0.79 and ≥0.85 for women, respectively.Results: Ignoring WHR, the risk of mortality for overweight subjects was similar to that for normal-weight subjects (HR: 1.09; 95% CI: 0.99, 1.19; P = 0.066). However, among normal-weight subjects, mortality increased for those with a higher WHR (HR: 1.33; 95% CI: 1.08, 1.65) compared with a lower WHR. Being overweight with a higher WHR was associated with substantial excess mortality (HR: 1.41; 95% CI: 1.25, 1.61) and greatly increased CAD incidence (sub-HR: 1.64; 95% CI: 1.39, 1.93) compared with being normal weight with a lower WHR. There was no interaction between physical activity and BMI plus WHR groups with respect to mortality.Conclusions: For healthier agers (i.e., nonsmokers without disease-associated weight loss), having central adiposity and a BMI corresponding to normal weight or overweight is associated with substantial excess mortality. The claimed BMI-defined overweight risk paradox may result in part from failing to account for central adiposity, rather than reflecting a protective physiologic effect of higher body-fat content in later life.

Dietary patterns and the risk of CVD and all-cause mortality in older British men

Dietary patterns are a major risk factor for cardiovascular morbidity and mortality; however, few studies have examined this relationship in older adults. We examined prospective associations between dietary patterns and the risk of CVD and all-cause mortality in 3226 older British men, aged 60-79 years and free from CVD at baseline, from the British Regional Heart Study. Baseline FFQ data were used to generate thirty-four food groups. Principal component analysis identified dietary patterns that were categorised into quartiles, with higher quartiles representing higher adherence to the dietary pattern. Cox proportional hazards examined associations between dietary patterns and risk of all-cause mortality and cardiovascular outcomes. We identified three interpretable dietary patterns: 'high fat/low fibre' (high in red meat, meat products, white bread, fried potato, eggs), 'prudent' (high in poultry, fish, fruits, vegetables, legumes, pasta, rice, wholemeal bread, eggs, olive oil) and 'high sugar' (high in biscuits, puddings, chocolates, sweets, sweet spreads, breakfast cereals). During 11 years of follow-up, 899 deaths, 316 CVD-related deaths, 569 CVD events and 301 CHD events occurred. The 'high-fat/low-fibre' dietary pattern was associated with an increased risk of all-cause mortality only, after adjustment for confounders (highest v. lowest quartile; hazard ratio 1·44; 95 % CI 1·13, 1·84). Adherence to a 'high-sugar' diet was associated with a borderline significant trend for an increased risk of CVD and CHD events. The 'prudent' diet did not show a significant trend with cardiovascular outcomes or mortality. Avoiding 'high-fat/low-fibre' and 'high-sugar' dietary components may reduce the risk of cardiovascular events and all-cause mortality in older adults.

Human longevity is influenced by many genetic variants: evidence from 75,000 UK Biobank participants

Variation in human lifespan is 20 to 30% heritable in twins but few genetic variants have been identified. We undertook a Genome Wide Association Study (GWAS) using age at death of parents of middle-aged UK Biobank participants of European decent (n=75,244 with father's and/or mother's data, excluding early deaths). Genetic risk scores for 19 phenotypes (n=777 proven variants) were also tested. In GWAS, a nicotine receptor locus(CHRNA3, previously associated with increased smoking and lung cancer) was associated with fathers' survival. Less common variants requiring further confirmation were also identified. Offspring of longer lived parents had more protective alleles for coronary artery disease, systolic blood pressure, body mass index, cholesterol and triglyceride levels, type-1 diabetes, inflammatory bowel disease and Alzheimer's disease. In candidate analyses, variants in the TOMM40/APOE locus were associated with longevity, but FOXO variants were not. Associations between extreme longevity (mother >=98 years, fathers >=95 years, n=1,339) and disease alleles were similar, with an additional association with HDL cholesterol (p=5.7x10-3). These results support a multiple protective factors model influencing lifespan and longevity (top 1% survival) in humans, with prominent roles for cardiovascular-related pathways. Several of these genetically influenced risks, including blood pressure and tobacco exposure, are potentially modifiable.

Diet quality in older age: the influence of childhood and adult socio-economic circumstances

Socio-economic gradients in diet quality are well established. However, the influence of material socio-economic conditions particularly in childhood, and the use of multiple disaggregated socio-economic measures on diet quality have been little studied in the elderly. In the present study, we examined childhood and adult socio-economic measures, and social relationships, as determinants of diet quality cross-sectionally in 4252 older British men (aged 60-79 years). A FFQ provided data on daily fruit and vegetable consumption and the Elderly Dietary Index (EDI), with higher scores indicating better diet quality. Adult and childhood socio-economic measures included occupation/father's occupation, education and household amenities, which combined to create composite scores. Social relationships included social contact, living arrangements and marital status. Both childhood and adult socio-economic factors were independently associated with diet quality. Compared with non-manual social class, men of childhood manual social class were less likely to consume fruit and vegetables daily (OR 0.80, 95% CI 0.66, 0.97), as were men of adult manual social class (OR 0.65, 95% CI 0.54, 0.79), and less likely to be in the top EDI quartile (OR 0.73, 95% CI 0.61, 0.88), similar to men of adult manual social class (OR 0.66, 95 % CI 0.55, 0.79). Diet quality decreased with increasing adverse adult socio-economic scores; however, the association with adverse childhood socio-economic scores diminished with adult social class adjustment. A combined adverse childhood and adulthood socio-economic score was associated with poor diet quality. Diet quality was most favourable in married men and those not living alone, but was not associated with social contact. Diet quality in older men is influenced by childhood and adulthood socio-economic factors, marital status and living arrangements.

High diet quality is associated with a lower risk of cardiovascular disease and all-cause mortality in older men

Although diet quality is implicated in cardiovascular disease (CVD) risk, few studies have investigated the relation between diet quality and the risks of CVD and mortality in older adults. This study examined the prospective associations between dietary scores and risk of CVD and all-cause mortality in older British men. A total of 3328 men (aged 60-79 y) from the British Regional Heart Study, free from CVD at baseline, were followed up for 11.3 y for CVD and mortality. Baseline food-frequency questionnaire data were used to generate 2 dietary scores: the Healthy Diet Indicator (HDI), based on WHO dietary guidelines, and the Elderly Dietary Index (EDI), based on a Mediterranean-style dietary intake, with higher scores indicating greater compliance with dietary recommendations. Cox proportional hazards regression analyses assessed associations between quartiles of HDI and EDI and risk of all-cause mortality, CVD mortality, CVD events, and coronary heart disease (CHD) events. During follow-up, 933 deaths, 327 CVD deaths, 582 CVD events, and 307 CHD events occurred. Men in the highest compared with the lowest EDI quartile had significantly lower risks of all-cause mortality (HR: 0.75; 95% CI: 0.60, 0.94; P-trend = 0.03), CVD mortality (HR: 0.63; 95% CI: 0.42, 0.94; P-trend = 0.03), and CHD events (HR: 0.66; 95% CI: 0.45, 0.97; P-trend = 0.05) but not CVD events (HR: 0.79; 95% CI: 0.60, 1.05; P-trend = 0.16) after adjustment for sociodemographic, behavioral, and cardiovascular risk factors. The HDI was not significantly associated with any of the outcomes. The EDI appears to be more useful than the HDI for assessing diet quality in relation to CVD and morality risk in older men. Encouraging older adults to adhere to the guidelines inherent in the EDI criteria may have public health benefits.

Sarcopenic obesity and risk of cardiovascular disease and mortality: a population-based cohort study of older men

Objectives

To examine associations between sarcopenia, obesity, and sarcopenic obesity and risk of cardiovascular disease (CVD) and all-cause mortality in older men.

Design

Prospective cohort study.

Setting

British Regional Heart Study.

Participants

Men aged 60–79 years (n = 4,252).

Measurements

Baseline waist circumference (WC) and midarm muscle circumference (MAMC) measurements were used to classify participants into four groups: sarcopenic, obese, sarcopenic obese, or optimal WC and MAMC. The cohort was followed for a mean of 11.3 years for CVD and all-cause mortality. Cox regression analyses assessed associations between sarcopenic obesity groups and all-cause mortality, CVD mortality, CVD events, and coronary heart disease (CHD) events.

Results

There were 1,314 deaths, 518 CVD deaths, 852 CVD events, and 458 CHD events during follow-up. All-cause mortality risk was significantly greater in sarcopenic (HR = 1.41, 95% CI = 1.22–1.63) and obese (HR = 1.21, 95% CI = 1.03–1.42) men than in the optimal reference group, with the highest risk in sarcopenic obese (HR = 1.72, 95% CI = 1.35–2.18), after adjustment for lifestyle characteristics. Risk of CVD mortality was significantly greater in sarcopenic and obese but not sarcopenic obese men. No association was seen between sarcopenic obesity groups and CHD or CVD events.

Conclusion

Sarcopenia and central adiposity were associated with greater cardiovascular mortality and all-cause mortality. Sarcopenic obese men had the highest risk of all-cause mortality but not CVD mortality. Efforts to promote healthy aging should focus on preventing obesity and maintaining muscle mass.

Low muscle mass in older men: the role of lifestyle, diet and cardiovascular risk factors

OBJECTIVE

To explore associations between low muscle mass and a wide range of lifestyle, dietary and cardiovascular risk factors in older men including metabolic risk factors, markers of inflammation, endothelial dysfunction and coagulation.

DESIGN

Cross-sectional study.

SETTING

British Regional Heart Study.

PARTICIPANTS

4252 men aged 60-79 years.

MEASUREMENTS

PARTICIPANTS attended a physical examination in 1998-2000, and completed a general questionnaire and a food frequency questionnaire. Low muscle mass was assessed by two measures: midarm muscle circumference (MAMC) and fat-free mass index (FFMI). Associations between risk factors and low muscle mass were analysed using logistic regression.

RESULTS

Physical inactivity, insulin resistance, C-reactive protein, von Willebrand factor and fibrinogen were associated with significantly increased odds of low MAMC and FFMI after adjustment for body mass index, lifestyle characteristics and morbidity. Those with higher percent energy intake from carbohydrates showed decreased odds of low MAMC (OR: 0.73, 95% CI: 0.55-0.96) and FFMI (OR: 0.76, 95% CI: 0.58-0.99). Other dietary variables, smoking, alcohol intake, D-dimer, interleukin 6 and homocysteine showed no important associations with MAMC and FFMI.

CONCLUSION

Increasing physical activity, consuming a diet with a high proportion of energy from carbohydrates, and taking steps to prevent insulin resistance and reduce inflammation and endothelial dysfunction may help to reduce the risk of low muscle mass in older men.

Pro-inflammatory alterations and status of blood plasma iron in a model of blast-induced lung trauma

Impact of blast shock waves (SW) with the body wall produces blast lung injuries characterized by bilateral traumatic hemorrhages. Such injuries often have no external signs, are difficult to diagnose, and therefore, are frequently underestimated. Predictive assessment of acute respiratory distress syndrome outcome in SW-related accidents should be based on experimental data from appropriate animal models. Blood plasma transferrin is a major carrier of blood iron essential for proliferative "emergency" response of hematopoietic and immune systems as well as injured tissue in major trauma. Iron-transferrin complexes (Fe3+ TRF) can be quantitatively analyzed in blood and tissue samples with low-temperature EPR techniques. We hypothesized that use of EPR techniques in combination with assays for pro-inflammatory cytokines and granulocytes in the peripheral blood and BAL would reveal a pattern of systemic sequestration of (Fe3+)TRF that could be useful for development of biomarkers of the systemic inflammatory response to lung injury. With this goal we (i) analyzed time-dependent dynamics of (Fe3+)TRF in the peripheral blood of rats after impacts of SW generated in a laboratory shock-tube and (ii) assayed the fluctuation of granulocyte (PMN) counts and expression of CD11b adhesion molecules on the surface of PMNs during the first 24 h after SW induced injury. Sham-treated animals were used as control. Exposure to SW led to a significant decrease in the amount of blood (Fe3+)TRF that correlated with the extent of lung injury and developed gradually during the first 24 h. Thus, sequestration of (Fe3+)TRF occurred as early as 3 h post-exposure. At that time, the steady state concentration of (Fe3+)TRF in blood samples decreased from 19.7+/-0.6 microM in controls to 7.5+/-1.3 microM in exposed animals. The levels of (Fe3+)TRF remained decreased throughout the entire study period. PMN counts increased 5-fold and 3.5-fold over controls respectively, at 3 and 6 h postexposure. These effects were accompanied by an increase in expression of CD11b on the surface membrane of PMNs. Extensive release of cytokines IL-1, IL-6, MCP-1, and MIP-2 was observed in BAL fluid and blood plasma during 24 h postexposure. We conclude that EPR monitoring of blood (Fe3+)TRF can be a useful approach for assessment of systemic pro-inflammatory alterations due to SW-induced lung injury.

The use of linezolid in the treatment of vancomycin-resistant enterococcal septicaemia in two patients with burn injuries

Vancomycin-resistant enterococci (VRE) are multi-resistant micro-organisms that have emerged as important nosocomial pathogens during the last decade. Emergence of this organism has been blamed mainly on the increased and inappropriate use of antibiotics, in particular, the cephalosporins and the glycopeptide, vancomycin. Burns patients are highly vulnerable to acquiring VRE infections, being both debilitated and immunocompromised, and often receiving antibiotics that further diminish their intrinsic microbial flora. We report on two patients with large burn injuries who acquired vancomycin-resistant enterococcal septicaemia during their in-patient stay. Both patients were successfully treated using the antibiotic, linezolid. Linezolid is the first in a new class of antibiotics known as the oxazolidinones whose mode of action inhibits early bacterial protein synthesis. Linezolid has a spectrum of activity against Gram-positive micro-organisms including methicillin-resistant Staphylococcus aureus (MRSA) and VRE, and can provide a useful treatment alternative to the glycopeptides.