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Clinical Gerontologist 2022: To characterize the inclusion of cognition in definitions of successful aging (SA) according to empirical studies published in peer-reviewed journals.: A systematic...
: To characterize the inclusion of cognition in definitions of successful aging (SA) according to empirical studies published in peer-reviewed journals.: A systematic review across ISI Web of Knowledge.: Of the 74 included studies, there were 65 studies (87.8%) analyzing cognition as one component of multicomponent SA model (cognitive component studies), and 9 studies (12.2%) focusing solely on successful cognitive aging (SCA studies). Most of the studies operationalized cognition in SA by defining SA group and analyzing single SA indicators. A minority of the studies calculated the SA index. Finally, emergent techniques to operationalize SA as a latent variable and emergent field of cognition in SA in pathology were identified.: The results highlight that cognition is being included in SA using different levels of complexity. Even though research investigating SA in pathology is emerging, there is currently a lack of utilization of the concept in pathological and at-risk populations.: The current research of cognition in SA provides several valid options to evaluate if a person is aging successfully. The emerging research indicates that people from at-risk and pathological populations can age successfully.
Topics: Aging; Cognition; Cognitive Aging; Humans
PubMed: 32336218
DOI: 10.1080/07317115.2020.1752346 -
Psychoneuroendocrinology Mar 2014One of the most consistent findings in the biology of depression is an altered activity of the hypothalamic-pituitary-adrenal (HPA) axis. However, data concerning this... (Meta-Analysis)
Meta-Analysis Review
One of the most consistent findings in the biology of depression is an altered activity of the hypothalamic-pituitary-adrenal (HPA) axis. However, data concerning this issue have never been examined with a focus on the older population. Here we present a systematic review and meta-analysis, based on studies investigating levels of cortisol, adrenocorticotropic hormone (ACTH) and corticotropin-releasing hormone (CRH) in depressed participants older than 60 and compared with healthy controls. We found 20 studies, for a total of 43 comparisons on different indices of HPA axis functioning. Depression had a significant effect (Hedges' g) on basal cortisol levels measured in the morning (0.89), afternoon (0.83) and night (1.39), but a smaller effect on cortisol measured continuously (0.51). The effect of depression was even higher on post-dexamethasone cortisol levels (3.22), whereas it was non-significant on morning ACTH and CRH levels. Subgroup analyses indicated that various methodological and clinical factors can influence the study results. Overall, older participants suffering from depression show a high degree of dysregulation of HPA axis activity, with differences compared with younger adults. This might depend on several mechanisms, including physical illnesses, alterations in the CNS and immune-endocrinological alterations. Further studies are needed to clarify the implications of altered HPA axis activity in older patients suffering from depression. Novel pharmacological approaches might be effective in targeting this pathophysiological feature, thus improving the clinical outcomes.
Topics: Adrenocorticotropic Hormone; Aging; Corticotropin-Releasing Hormone; Depression; Dexamethasone; Humans; Hydrocortisone; Hypothalamo-Hypophyseal System; Pituitary-Adrenal Function Tests; Pituitary-Adrenal System
PubMed: 24495607
DOI: 10.1016/j.psyneuen.2013.12.004 -
Clinical Interventions in Aging 2021Contextual processing (or context processing; CP) is an integral component of cognition. CP allows people to manage their thoughts and actions by adjusting to...
Contextual processing (or context processing; CP) is an integral component of cognition. CP allows people to manage their thoughts and actions by adjusting to surroundings. CP involves the formation of an internal representation of context in relation to the environment, maintenance of this information over a period of time, and the updating of mental representations to reflect changes in the environment. Each of these functions can be affected by aging and associated conditions. Here, we introduced contextual processing research and summarized the literature studying the impact of normal aging and neurodegeneration-related cognitive decline on CP. Through searching the PubMed, PsycINFO, and Google Scholar databases, 23 studies were retrieved that focused on the impact of aging, mild cogniitve impairment (MCI), Alzheimer's disease (AD), and Parkinson's disease (PD) on CP. Results indicated that CP is particularly vulnerable to aging and neurodegeneration. Older adults had a delayed onset and reduced amplitude of electrophysiological response to information detection, comparison, and execution. MCI patients demonstrated clear signs of impaired CP compared to normal aging. The only study on AD suggested a decreased proactive control in AD participants in maintaining contextual information, but seemingly intact reactive control. Studies on PD restricted to non-demented older participants, who showed limited ability to use contextual information in cognitive and motor processes, exhibiting impaired reactive control but more or less intact proactive control. These data suggest that the decline in CP with age is further impacted by accelerated aging and neurodegeneration, providing insights for improving intervention strategies. This review highlights the need for increased attention to research this important but understudied field.
Topics: Aging; Alzheimer Disease; Cognition; Cognitive Dysfunction; Humans; Parkinson Disease
PubMed: 33658771
DOI: 10.2147/CIA.S287619 -
BMC Geriatrics Aug 2022Healthy aging relies on mitochondrial functioning because this organelle provides energy and diminishes oxidative stress. Single nucleotide polymorphisms (SNPs) in...
INTRODUCTION
Healthy aging relies on mitochondrial functioning because this organelle provides energy and diminishes oxidative stress. Single nucleotide polymorphisms (SNPs) in TOMM40, a critical gene that produces the outer membrane protein TOM40 of mitochondria, have been associated with mitochondrial dysfunction and neurodegenerative processes. Yet it is not clear whether or how the mitochondria may impact human longevity. We conducted this review to ascertain which SNPs have been associated with markers of healthy aging.
METHODS
Using the PRISMA methodology, we conducted a systematic review on PubMed and Embase databases to identify associations between TOMM40 SNPs and measures of longevity and healthy aging.
RESULTS
Twenty-four articles were selected. The TOMM40 SNPs rs2075650 and rs10524523 were the two most commonly identified and studied SNPs associated with longevity. The outcomes associated with the TOMM40 SNPs were changes in BMI, brain integrity, cognitive functions, altered inflammatory network, vulnerability to vascular risk factors, and longevity.
DISCUSSIONS
Our systematic review identified multiple TOMM40 SNPs potentially associated with healthy aging. Additional research can help to understand mechanisms in aging, including resilience, prevention of disease, and adaptation to the environment.
Topics: Aging; Healthy Aging; Humans; Longevity; Membrane Transport Proteins; Mitochondrial Precursor Protein Import Complex Proteins; Polymorphism, Single Nucleotide
PubMed: 35964003
DOI: 10.1186/s12877-022-03337-4 -
The Gerontologist Jul 2019There is considerable heterogeneity in experiences of aging, with some experiencing greater well-being and adapting more successfully to the challenges of aging than... (Meta-Analysis)
Meta-Analysis
ABSTRACT BACKGROUND AND OBJECTIVES
There is considerable heterogeneity in experiences of aging, with some experiencing greater well-being and adapting more successfully to the challenges of aging than others. Self-compassion is a modifiable psychological skill that might help explain individual differences in well-being and adjustment in later life. The aim of this study was to systematically review the literature on self-compassion and well-being outcomes in studies of older adults aged 65 and older.
RESEARCH DESIGN AND METHODS
This systematic review was conducted according to PRISMA guidelines, using databases PsycINFO, Medline, and Embase. The search term self-compassion was paired with terms relating to well-being, psychological symptoms, and adjustment. Meta-analysis was used to synthesize results on the relationship between self-compassion and four outcomes including depression, anxiety, hedonic well-being, and eudaimonic well-being.
RESULTS
Eleven studies met inclusion criteria for this review. Meta-analysis revealed that self-compassion was associated with lower levels of depression (r = -.58, 95% CI [-.66, -.48]) and anxiety (r = -.36, 95% CI [-.60, -.07]), and higher levels of hedonic (r = .41, 95% CI [.15, .62]) and eudaimonic (r = .49, 95% CI [.41, .57]) well-being. Further, three studies found self-compassion weakened the impact of physical symptoms on well-being outcomes.
DISCUSSION AND IMPLICATIONS
We found preliminary evidence that self-compassion is associated with well-being outcomes in older adults, and that self-compassion may buffer the psychological sequelae of health symptoms in later life. Higher quality studies with uniform outcome measures are needed to replicate and extend these results.
Topics: Aging; Anxiety; Depression; Empathy; Humans; Mental Health; Self Concept
PubMed: 30169673
DOI: 10.1093/geront/gny108 -
Mechanisms of Ageing and Development Apr 2022Nervous system maladaptation is linked to the loss of maximal strength and motor control with aging. Motor unit discharge rates are a critical determinant of force... (Meta-Analysis)
Meta-Analysis Review
Nervous system maladaptation is linked to the loss of maximal strength and motor control with aging. Motor unit discharge rates are a critical determinant of force production; thus, lower discharge rates could be a mechanism underpinning maximal strength and motor control losses during aging. This meta-analysis summarized the findings of studies comparing motor unit discharge rates between young and older adults, and examined the effects of the selected muscle and contraction intensity on the magnitude of discharge rate difference between these two groups. Estimates from 29 studies, across a range of muscles and contraction intensities, were combined in a multilevel meta-analysis, to investigate whether discharge rates differed between young and older adults. Motor unit discharge rates were higher in younger than older adults, with a pooled standardized mean difference (SMD) of 0.66 (95%CI= 0.29-1.04). Contraction intensity had a significant effect on the pooled SMD, with a 1% increase in intensity associated with a 0.009 (95%CI= 0.003-0.015) change in the pooled SMD. These findings suggest that reductions in motor unit discharge rates, especially at higher contraction intensities, may be an important mechanism underpinning age-related losses in maximal force production.
Topics: Aged; Aging; Humans; Isometric Contraction; Motor Neurons; Muscle Contraction; Muscle, Skeletal; Patient Discharge
PubMed: 35218849
DOI: 10.1016/j.mad.2022.111647 -
Experimental Gerontology Mar 2014It is widely believed that females have longer telomeres than males, although results from studies have been contradictory. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
It is widely believed that females have longer telomeres than males, although results from studies have been contradictory.
METHODS
We carried out a systematic review and meta-analyses to test the hypothesis that in humans, females have longer telomeres than males and that this association becomes stronger with increasing age. Searches were conducted in EMBASE and MEDLINE (by November 2009) and additional datasets were obtained from study investigators. Eligible observational studies measured telomeres for both females and males of any age, had a minimum sample size of 100 and included participants not part of a diseased group. We calculated summary estimates using random-effects meta-analyses. Heterogeneity between studies was investigated using sub-group analysis and meta-regression.
RESULTS
Meta-analyses from 36 cohorts (36,230 participants) showed that on average females had longer telomeres than males (standardised difference in telomere length between females and males 0.090, 95% CI 0.015, 0.166; age-adjusted). There was little evidence that these associations varied by age group (p=1.00) or cell type (p=0.29). However, the size of this difference did vary by measurement methods, with only Southern blot but neither real-time PCR nor Flow-FISH showing a significant difference. This difference was not associated with random measurement error.
CONCLUSIONS
Telomere length is longer in females than males, although this difference was not universally found in studies that did not use Southern blot methods. Further research on explanations for the methodological differences is required.
Topics: Adult; Aged; Aged, 80 and over; Aging; Female; Humans; Male; Middle Aged; Sex Factors; Telomere
PubMed: 24365661
DOI: 10.1016/j.exger.2013.12.004 -
Experimental Gerontology Apr 2020Nicotinamide adenine dinucleotide (NAD+) is an essential pyridine nucleotide that is present in all living cells. NAD+ acts as an important cofactor and substrate for a...
Nicotinamide adenine dinucleotide (NAD+) is an essential pyridine nucleotide that is present in all living cells. NAD+ acts as an important cofactor and substrate for a multitude of biological processes including energy production, DNA repair, gene expression, calcium-dependent secondary messenger signalling and immunoregulatory roles. The de novo synthesis of NAD+ is primarily dependent on the kynurenine pathway (KP), although NAD+ can also be recycled from nicotinic acid (NA), nicotinamide (NAM) and nicotinamide riboside (NR). NAD+ levels have been reported to decline during ageing and age-related diseases. Recent studies have shown that raising intracellular NAD+ levels represents a promising therapeutic strategy for age-associated degenerative diseases in general and to extend lifespan in small animal models. A systematic review of the literature available on Medline, Embase and Pubmed was undertaken to evaluate the potential health and/or longevity benefits due to increasing NAD+ levels. A total of 1545 articles were identified and 147 articles (113 preclinical and 34 clinical) met criteria for inclusion. Most studies indicated that the NAD+ precursors NAM, NR, nicotinamide mononucleotide (NMN), and to a lesser extent NAD+ and NADH had a favourable outcome on several age-related disorders associated with the accumulation of chronic oxidative stress, inflammation and impaired mitochondrial function. While these compounds presented with a limited acute toxicity profile, evidence is still quite limited and long-term human clinical trials are still nascent in the current literature. Potential risks in raising NAD+ levels in various clinical disorders using NAD+ precursors include the accumulation of putative toxic metabolites, tumorigenesis and promotion of cellular senescence. Therefore, NAD+ metabolism represents a promising target and further studies are needed to recapitulate the preclinical benefits in human clinical trials.
Topics: Aging; Animals; Humans; Inflammation; Mice; NAD; Neurodegenerative Diseases; Niacinamide; Nicotinamide Mononucleotide; Oxidative Stress; Pyridinium Compounds; Rats; Risk Assessment
PubMed: 31917996
DOI: 10.1016/j.exger.2020.110831 -
Ageing Research Reviews Mar 2014As for the whole human body, the kidney undergoes age-related changes which translate in an inexorable and progressive decline in renal function. Renal aging is a... (Review)
Review
As for the whole human body, the kidney undergoes age-related changes which translate in an inexorable and progressive decline in renal function. Renal aging is a multifactorial process where gender, race and genetic background and several key-mediators such as chronic inflammation, oxidative stress, the renin-angiotensin-aldosterone (RAAS) system, impairment in kidney repair capacities and background cardiovascular disease play a significant role. Features of the aging kidney include macroscopic and microscopic changes and important functional adaptations, none of which is pathognomonic of aging. The assessment of renal function in the framework of aging is problematic and the question whether renal aging should be considered as a physiological or pathological process remains a much debated issue. Although promising dietary and pharmacological approaches have been tested to retard aging processes or renal function decline in the elderly, proper lifestyle modifications, as those applicable to the general population, currently represent the most plausible approach to maintain kidney health.
Topics: Age Factors; Aging; Animals; Humans; Kidney; Kidney Function Tests; Renal Insufficiency
PubMed: 24548926
DOI: 10.1016/j.arr.2014.02.003 -
Schizophrenia Research Aug 2022Evidence suggests that schizophrenia (SZ) is associated with accelerated biological aging. DNA methylation can be used as an indicator of biological aging by means of... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Evidence suggests that schizophrenia (SZ) is associated with accelerated biological aging. DNA methylation can be used as an indicator of biological aging by means of epigenetic clock estimates.
OBJECTIVE
The aim of this systematic review and meta-analysis was to investigate the association between SZ and different epigenetic clocks.
METHODS
Search terms were applied in different databases: Embase, MEDLINE (EBSCO), Cochrane Central Register of Controlled Trials, PubMed, PsychINFO and Web of Science. To assess for risk of bias we utilized an adapted version of the Newcastle-Ottawa Scale. Meta-analyses were conducted using the random effects model and meta-regressions were used to assess factors associated with heterogeneity.
RESULTS
Eight studies were included (Controls, n = 3394; SZ subjects, n = 3096), which analyzed five different epigenetic clocks. Overall meta-analysis revealed no significant differences between SZ and controls on epigenetic aging (Standardized Mean Difference - SMD = -0.21; p = 0.13). However, epigenetic clock method was a significant moderator of heterogeneity (p = 0.004). Using Horvath's clock as reference, higher SMD's were found for PhenoAge and Intrinsic epigenetic age acceleration (IEAA) clocks. In a stratified meta-analysis restricted to the two clocks mentioned above, a significant accelerating effect was found in patients with SZ when compared to controls (SMD = 0.29; p = 0.003).
CONCLUSION
Our findings suggest that the method of epigenetic clocks is a critical factor associated with estimates of aging acceleration in SZ. However, more studies are needed to confirm these findings and in order to evaluate a possible minor effect in overall analysis.
Topics: Aging; DNA Methylation; Epigenesis, Genetic; Epigenomics; Humans; Schizophrenia
PubMed: 35780750
DOI: 10.1016/j.schres.2022.06.029