Frailty syndrome, biomarkers and environmental factors - A pilot study

Effect of Continuous Positive Airway Pressure on Incident Frailty in Elderly Patients with Obstructive Sleep Apnea: A Study Based on Propensity Score Matching

Background

The concomitant rise in the prevalence of obstructive sleep apnea (OSA) and frailty among the elderly population has been linked to an increase in mortality rates. Despite continuous positive airway pressure (CPAP) being the gold standard treatment for OSA, its impact on incident frailty remains inadequately explored.

Methods

In this cohort study, we analyzed data from 1290 patients diagnosed with OSA, aged 60 years and older. A subset of 71 patients who demonstrated high adherence to CPAP therapy were categorized as the CPAP group. Propensity score matching (PSM) was employed at a 1:4 ratio, matching for variables such as age, gender, body mass index (BMI), and sleep apnea-hypopnea index (AHI), to establish a non-CPAP group for comparison. The FRAIL scale was utilized to evaluate the frailty status of participants. Logistic regression analysis examined the relationship between CPAP therapy and incident frailty, as well as its individual components, in elderly patients with OSA.

Results

During a median follow-up period of 52 months, incident frailty was observed in 70 patients (19.7%). Patients with OSA receiving CPAP therapy exhibited a lower incidence of frailty compared to those not receiving CPAP (11.26% vs 21.83%, P=0.045). In the multivariate model, CPAP therapy was significantly correlated with a reduced risk of incident frailty (OR = 0.36, 95% CI, 0.15-0.88; P = 0.025). Subcomponent analyses revealed that CPAP was associated with a lower risk of fatigue (OR=0.35, 95% CI, 0.19-0.63; P < 0.001), resistance (OR = 0.32, 95% CI, 0.14-0.74; P=0.008), and weight loss (OR = 0.38, 95% CI, 0.19-0.75; P = 0.007).

Conclusion

CPAP therapy was associated with a reduced risk of incident frailty among elderly patients with OSA.

Frailty, sex, and poverty are associated with DNA damage and repair in frail, middle-aged urban adults

Frailty is an age-related syndrome characterized by reduced recovery from stressors and increased risks of morbidity and mortality. Although frailty is usually studied in those over 65 years, our previous work showed that frailty is both present and a risk factor for premature mortality in midlife. We identified altered gene expression patterns and biological pathways associated with inflammation in frailty. Evidence suggests DNA oxidation damage related to inflammation accumulates with age, and that DNA repair capacity (DRC) declines with age and age-related conditions. We hypothesized that inter-individual differences in DNA oxidation damage and DRC are associated with frailty status and poverty level. Using the CometChip assay, we assessed baseline single-strand breaks and hydrogen peroxide (H2O2)-induced DNA oxidation damage and DRC in non-frail and frail middle-aged African American and White individuals with household incomes above and below poverty. Analysis of baseline single-strand breaks showed no associations with frailty, poverty, race, or sex. However, we identified an interaction between frailty and poverty in H2O2-induced DNA oxidation damage. We also identified interactions between sex and frailty as well as sex and poverty status with DRC. The social determinant of health, poverty, associates with DRC in men. Baseline DNA damage, H2O2-induced DNA damage as well as DRC were associated with serum cytokine levels. IL-10 levels were inversely associated with baseline DNA damage as well as H2O2-induced DNA damage, DRC was altered by IL-4 levels and sex, and by TNF-α levels in the context of sex and poverty status. This is the first evidence that DRC may be influenced by poverty status at midlife. Our data show that social determinants of health should be considered in examining biological pathways through which disparate age-related health outcomes become manifest.

Frailty biomarkers under the perspective of geroscience: A narrative review

Cellular and molecular aging biomarkers might contribute to identify at-risk individuals for frailty before overt clinical manifestations appear. Although studies on the associations of aging biomarkers and frailty exist, no investigation has gathered this information using a structured framework for identifying aging biomarkers; as a result, the evidence on frailty and aging biomarkers is diffuse and incomplete. Therefore, this narrative review aimed to gather information on the associations of the hallmarks of aging and frailty under the perspective of geroscience. The literature on human studies on this topic is sparse and mainly composed of cross-sectional investigations performed in small study samples. The main putative aging biomarkers associated to frailty were: mitochondrial DNA copy number (genomic instability and mitochondrial dysfunction), telomere length (telomere attrition), global DNA methylation (epigenetic alterations), Hsp70 and Hsp72 (loss of proteostasis), IGF-1 and SIRT1 (deregulated nutrient-sensing), GDF-15 (mitochondrial dysfunction, cellular senescence and altered intercellular communication), CD4 + and CD8 + cell percentages (cellular senescence), circulating osteogenic progenitor (COP) cells (stem cell exhaustion), and IL-6, CRP and TNF-alpha (altered intercellular communication). IGF-1, SIRT1, GDF-15, IL-6, CRP and TNF-alpha presented more evidence among these biomarkers, highlighting the importance of inflammation and nutrient sensing on frailty. Further longitudinal studies investigating biomarkers across the hallmarks of aging would provide valuable information on this topic.

Association of blood lead exposure with frailty and its components among the Chinese oldest old

Lead (Pb) is a widespread environmental contaminant, associated with a higher risk of functional impairment that can lead to frailty in older adults. However, few studies focused on the association of Pb exposure with frailty among the oldest old (aged ≥ 80 years). In this study, we aimed to assess the associations of Pb with frailty and its components in the oldest old. The included individuals were the oldest old aged ≥ 80 years who participated in a 2017 cross-sectional survey of the Healthy Aging and Biomarkers Cohort Study. Frailty was ascertained by the frailty index, which was created based on health deficits. We used logistic regression models to estimate the association of blood Pb with frailty and its components. The geometric mean and median of blood Pb were 38.51 μg/L and 36.27 μg/L among the oldest old, respectively. Compared with the first quartile of blood Pb, participants in the fourth quartile had higher risk of frailty and its components, the ORs are 1.71 (1.22-2.41), 1.99 (1.35-2.94), 1.91 (1.25-2.93), 1.57 (1.13-2.17) and 1.43 (1.05-1.96), for frailty, ADL disability, IADL disability, functional limitations, and hearing loss in the oldest old, respectively. There was a significant interaction between blood Pb and frailty in different age groups. In conclusion, our findings provide preliminary evidence that higher blood Pb may increase the risk of frailty among the oldest old by increasing the risk of disability in four physical functions: disability in ADL, disability in IADL, functional limitations, and hearing loss.

DNA damage in circulating hematopoietic progenitor stem cells as promising biological sensor of frailty

Frailty is an age-related syndrome that exposes individuals to increased vulnerability. Although it is potentially reversible, in most cases it leads to negative outcomes, including mortality. The different methods proposed identify frailty after the onset of clinical manifestations. An early diagnosis might make it possible to manage the frailty progression better. The frailty pathophysiology is still unclear although mechanisms, in particular, those linked to inflammation and immunosenescence, have been investigated. A common feature of several clinical aspects involved in senescent organisms is the increase of oxidative stress, described as one of the major causes of deoxyribonucleic acid (DNA) damage accumulation in aged cells including the adult stem cell compartment. Likely, this accumulation is implicated in frailty status. The oxidative status of our frail, pre-frail, and non-frail population was characterized. In addition, the DNA damage in hematopoietic cells was evidenced by analyzing the peripheral blood mononuclear cell and their T lymphocyte, monocyte, circulating hematopoietic progenitor stem cell (cHPSC) subpopulations. The phosphorylation of C-terminal of histone H2AX at amino acid Ser 139 (γ-H2AX), which occurs at the DNA double-strand break focus, was evaluated. In our frail population, increased oxidative stress and a high level of DNA damage in cHPSC were found. This study may have potential implications because the increment of DNA damage in cHPSC could be suggestive of an organism impairment preceding the evident frailty. In addition, it may open the possibility for attenuation of frailty progression throughout specific drugs acting on preventing DNA damage or removing damaged cells

Secondhand smoke is positively associated with pre-frailty and frailty in non-smoking older adults

INTRODUCTION

Either exposure to secondhand smoke (SHS) or frailty has been linked to adverse health outcomes in nonsmoking adults. However, their relationship is rarely studied. The purpose of this study is to examine the association between serum cotinine level and frailty status among non-smoking older adults.

METHOD

The study population consisted of 2,703 older adults aged ≥60 from the National Health and Nutrition Examination Survey 2011-2014. Non-smokers were included based on (1) a serum cotinine level ≤ 10 ng/mL and 2) a response of "no" to the question, "Do you currently smoke?" Frailty status was measured based on the Fried Phenotype and had three groups- robust, pre-frailty, and frailty. Multinomial logistic regression models were constructed to examine the association between serum cotinine level quartile and frailty status, controlling for age, sex, race/ethnicity, education, depressive symptoms, alcohol use, and systolic blood pressure.

RESULTS

About half of the participants (median age 70.0 years, range 64-78) were female (53.6%), non-Hispanic White (48.3%), and completed some college and above (50.1%). Multinomial logistic regression with a reference group being those in the 1^st quantile (the lowest) of serum cotinine level showed that participants in the 4^th quartile (the highest) of serum cotinine level had increased odds of pre-frailty vs. robust (OR 1.522, 95% confidence interval [CI] 1.060, 2.185, P = 0.023) as well as increased odds of frailty vs. robust (OR 2.349, 95% CI 1.081, 5.107, P = 0.031).

CONCLUSIONS

Higher serum cotinine level is associated with increased risk of pre-frailty and frailty versus robust in non-smoking older adults. Prevention and reduction of SHS in older adults may help protect them from developing pre-frailty or frailty.

Exploring Early Detection of Frailty Syndrome in Older Adults: Evaluation of Oxi-Immune Markers, Clinical Parameters and Modifiable Risk Factors

Ageing is accompanied with a decline in several physiological systems. Frailty is an age-related syndrome correlated to the loss of homeostasis and increased vulnerability to stressors, which is associated with increase in the risk of disability, comorbidity, hospitalisation, and death in older adults. The aim of this study was to understand the relationship between frailty syndrome, immune activation, and oxidative stress. Serum concentrations of vitamins A and E were also evaluated, as well as inflammatory biomarkers (CRP and IL-6) and oxidative DNA levels. A group of Portuguese older adults (≥65 years old) was engaged in this study and classified according to Fried’s frailty phenotype. Significant increases in the inflammatory mediators (CRP and IL-6), neopterin levels, kynurenine to tryptophan ratio (Kyn/Trp), and phenylalanine to tyrosine ratio (Phe/Tyr), and significant decreases in Trp and Tyr concentrations were observed in the presence of frailty. IL-6, neopterin, and Kyn/Trp showed potential as predictable biomarkers of frailty syndrome. Several clinical parameters such as nutrition, dependency scales, and polypharmacy were related to frailty and, consequently, may influence the associations observed. Results obtained show a progressive immune activation and production of pro-inflammatory molecules in the presence of frailty, agreeing with the inflammageing model. Future research should include different dimensions of frailty, including psychological, social, biological, and environmental factors.

Association between Phthalate Exposure and Frailty among Community-Dwelling Older Adults: A Repeated Panel Data Study

Only a few studies have examined the impacts of environmental exposure on frailty. This study investigated the association between phthalates and frailty among community-dwelling older adults. The Korean Elderly Environmental Panel II (KEEP II) study is a repeated panel data study of 800 community-dwelling older adults in South Korea. Frailty was measured with five items defined by Fried and colleagues. Environmental pollutants in the form of two types of metabolites for Di-ethylhexyl phthalate (DEHPs)-Mono (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and Mono (2-ethyl-5-oxohexyl) phthalate (MEOHP)-were obtained from urine specimens. Analyses were performed using repeated linear mixed models. The concentration levels of both MEOHP and MEHHP in urine were significantly higher in the pre-frail or frail group than its counterparts. While adjusting for covariates, MEOHP level was positively associated with the likelihood of being pre-frail or frail in both males and females; the concentration level of MEHHP also had a positive impact on the likelihood of being pre-frail or frail in females. The DEHP metabolite concentrations were significantly lower among adults with daily fruit consumption in both males and females. DEHPs, measured by metabolite concentrations, may increase the risk of frailty among older men and women; further studies are necessary. The preventive effects of nutrition on DEHP risk should also be further investigated.

Recent applications of the Comet Assay: A report from the International Comet Assay Workshop 2019

The International Comet Assay Workshops (ICAW) are a series of scientific conferences dealing with different aspects of the comet assay. The assay itself is a simple method for the detection of DNA strand breaks at the cellular level and can be applied to any cell type derived from different organs and tissues of eukaryotic organisms. Additionally, the comet assay is widely applied in human biomonitoring, ecotoxicology, genotoxicity testing of chemicals, but also in basic research studying the mechanisms of DNA damage and repair. The 2019 ICAW edition gathered about 80 participants with over 30 lecturers, 27 poster presentations and 2 open discussion sessions presenting the latest advances in technical developments as well as applications of the comet assay in genetic toxicology, and environmental and human biomonitoring. This report summarises the important issues that were raised and discussed during the sessions as well as a short synopsis of the papers selected for inclusion in this special issue. Based on the topics presented at the workshop, the assay with its new modifications and applications has a bright future and will for sure stay one of the most popular methods in genetic toxicology and beyond in the years to come.