Age and ageing最新文献

Background: Delirium is common in hospitalised older people and is associated with a poor prognosis. It remains poorly characterised at a molecular level. We studied the metabolic signature of delirium using 1H-Magnetic Resonance Spectroscopy (MRS) in a prospective case-control study.

Methods: Medical inpatients aged ≥65 with and without delirium (DSM-5) were recruited and assessed for illness severity, frailty and prior cognitive decline. Metabolite concentrations in parietal white matter were obtained using MRS with diffusion MRI used to assess structural changes via the ADC.

Results: Out of 38 participants, 25 completed the MRS protocol (13 males and 12 females, mean age 80.5, SD = 6.47). Patients with delirium (n = 13) had greater pre-admission frailty than those without (n = 12) (median Clinical Frailty Scale 5 vs. 4.5; P = .049). There were no significant differences in age, sex, measures of MRS quality, atrophy and white matter disease. In a General Linear Model using the MRS voxel ADC to account for white matter lesion effects, glutamate was higher in delirium patients (P = 0.024). There were no other between-group differences in metabolite concentrations. For patients with and without delirium combined, glutamine increased with age and decreased with cortical atrophy, whilst Myo-inositol decreased with age and increased with median ADC.

Conclusions: Our results suggest that delirium is characterised by elevated brain glutamate concentration. This could cause excitotoxic brain injury and contribute to post-delirium cognitive decline and is a potentially modifiable process that merits further investigation.

Background: Sarcopenia is increasingly recognised as a systemic metabolic disorder involving lipid dysregulation, adipose tissue dysfunction, and adipokine imbalance. However, there is a lack of quantitative synthesis with sex-specific analyses.

Methods: Following PRISMA 2020 guidelines, we searched PubMed, Scopus, Web of Science, Cochrane Library, CNKI, WanFang, and VIP for studies published from January 2015 to December 2024 that compared lipid panels, adipokines, adiposity, muscle indices, and inflammatory markers in sarcopenic and non-sarcopenic adults. Random-effects meta-analyses and meta-regression were performed. Heterogeneity was assessed using I2 statistics, and publication bias was evaluated with funnel plots and Trim-and-Fill procedures.

Results: Fifty-two studies (N > 30 000) met the inclusion criteria. Sarcopenia was associated with a modest increase in LDL-C (SMD = 0.13; P = .0022), particularly in females (SMD = 0.46). HDL-C levels significantly increased in females (SMD = 6.71; P = .03). No significant changes were observed for triglycerides, total cholesterol, adiponectin, or leptin. Waist circumference increased significantly (SMD = 5.82 cm; P = .25), and muscle indices (SMI, ASMI, SMM) were lower in sarcopenia. Inflammatory markers (TNF-α, IL-6, IL-8) showed no significant associations. Subgroup analyses revealed significant effects by sex, measurement methods, and sarcopenia definitions, with meta-regression indicating these factors influenced lipid marker changes.

Conclusion: This meta-analysis integrates lipid fractions, adipokines, adiposity markers, and sex-specific differences in sarcopenia. Our findings highlight the significant rise in HDL-C in females and suggest the need for sex-targeted interventions. Further longitudinal studies are needed to clarify causality and refine clinical practice in sarcopenia management. The protocol was registered on PROSPERO (CRD42024626636).

Background: Primary care services play a key role in dementia care, yet activity may vary between subtypes.

Objective: To investigate longitudinal determinants of primary care contact across Alzheimer's disease (ad), vascular dementia (VD), dementia with Lewy bodies (DLB), and Parkinson's disease dementia (PDD) 5 years pre-and-post-diagnosis, encompassing clinical, cognitive, functional, and sociodemographic factors.

Design: Retrospective cohort study.

Methods: Data on 4384 individuals with first dementia diagnoses (2008-2023) were obtained from a South London catchment linking dementia services with primary care records. Linear mixed-effects models were run on 3-month interval counts (up to 40 intervals per individual, 20 pre-and-post-diagnosis). Separate pre-and-post-diagnosis models assessed longitudinal trends, adjusted for age, sex, and antidepressant use, with subgroup analyses by dementia subtype and cognitive status.

Result: Service utilisation increased over time, with VD showing a steeper pre-diagnosis rise and PDD moderate post-diagnosis increases compared to ad. Across both periods, worse cognitive impairment and antipsychotic receipt were associated with lower contacts, while older age and Black/British Black ethnicity were associated with higher contact. Pre-diagnosis, agitation, depressed mood, relationship and living conditions problems were linked to lower contact, whereas hallucinations were associated with higher use. Post-diagnosis, hypnotic/anxiolytic use predicted lower contact, while acetylcholinesterase inhibitor receipt, comorbidities, daily living difficulties, and mixed ethnicity were associated with increased utilisation.

Conclusion: Person-centred care pathways should anticipate subtype-specific and individual patterns, providing targeted support for those with reduced pre-diagnosis contact who may have unmet needs, while considering early intervention for groups anticipated to require increased service use after diagnosis.

Background: In younger individuals, fitness is mostly influenced by muscle mitochondrial oxidative phosphorylation (OxPhos) and cardiac output. However, compared with younger individuals, various impairments may also negatively affect fitness in older adults.

Objective: To investigate the relationship of OxPhos with cardiorespiratory fitness, the energetic cost of walking and aerobic resilience with respect to age.

Design: Cross-sectional.

Setting: Population.

Subjects: Six hundred and forty-nine Baltimore longitudinal study of ageing participants (mean age 64.5 years, 56.9% females).

Methods: Muscle mitochondrial OxPhos was measured as phosphocreatine recovery rate (kPCr) through 31P magnetic resonance spectroscopy. Based on age- and sex-specific kPCr z-scores, we classified individuals with low (≤ -0.5 standard deviations [SD]), average (-0.5 to 0.5SD) and high (>0.5SD) OxPhos. Cardiorespiratory fitness was measured as peak oxygen consumption (MVO2 peak) during a treadmill testing. The energetic cost of usual pace walking was expressed as the average oxygen consumption per 100 metres. Aerobic resilience was the ratio between MVO2 peak and average VO2 during usual pace walking.

Results: Participants with higher kPCr had 4.07 (95%CI: 2.88, 5.26) ml/kg/min higher MVO2 peak and 0.19 (95%CI: 0.06, 0.32) higher aerobic resilience than those with lower kPCr. The energetic cost of walking was greater by 0.84 (95% CI: 0.21, 1.47) ml/kg/100 m in those with high than low kPCr. A multiplicative interaction between age and kPCr was identified in the regressions predicting MVO2 peak and aerobic resilience (pinteraction = 0.01), with differences between OxPhos groups attenuating after age 70.

Conclusion: Muscle mitochondrial OxPhos contributes to interindividual variability in cardiorespiratory fitness, especially in young and middle adulthood.