Subjective Age and Cystatin C Among Older Adults

Longitudinal effects of subjective aging on health and longevity: An updated meta-analysis

This article updates and extends an earlier meta-analysis (Westerhof et al., 2014) on the longitudinal effects of subjective aging (SA) on health outcomes. A systematic search in different databases (APA PsycInfo, PubMed, Web of Science, and Scopus) resulted in 99 articles, reporting on 107 studies. Participants: Studies had a median sample size of 1,863 adults with a median age of 66 years. A randomized effect meta-analysis showed a significant, small effect (likelihood ratio = 1.347; 95% confidence interval [1.300, 1.396]; p < .001), similar in magnitude to the previous meta-analysis of 19 studies. Although the results showed high heterogeneity in the longitudinal link between SA and health outcomes, there were no differences in effects according to chronological age of participants, welfare state status (more or less developed social security system), length of follow-up, type of health-related outcome, or quality of the study. Effects were stronger for multiitem measures of self-perceptions of aging than for the frequently used single-item measures assessing subjective age, especially for indicators of physical health. Based on this meta-analysis, building on five times more studies than the 2014 review, we consider the associations of measures of SA with health and longevity across time as robust, albeit small in size. Future research should concentrate on the clarification of pathways mediating the relation between SA and health outcomes, as well as potential bidirectional effects. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The Mediating Role of Biomarkers in the Association Between Subjective Aging and Episodic Memory

OBJECTIVES

Subjective aging, indexed by subjective age and self-perceptions of aging (SPA), is consistently related to cognition in adulthood. The present study examined whether blood biomarkers mediate the longitudinal associations between subjective aging indices and memory.

METHODS

Data of 5,369 individuals aged 50-94 years (mean = 66.89 years, SD = 9.22; 60% women) were drawn from the Health and Retirement Study (HRS). Subjective age, SPA, and demographic factors were assessed in 2012/2014. Interleukin-6, C-reactive protein, albumin, cystatin C, N-terminal pro B-type natriuretic peptide (NT-proBNP), fasting glucose, Vitamin D, hemoglobin, red cells distribution width, and epigenetic aging were assessed as part of the HRS Venuous Blood Study in 2016. Memory was measured in 2018. The mediators (except for epigenetic aging, which was assessed in a subsample) were tested simultaneously in models that accounted for demographic covariates.

RESULTS

An older subjective age was related to worse memory partially through higher fasting glucose, higher cystatin C, higher NT-proBNP, and accelerated epigenetic aging. Negative SPA was related to worse memory through lower Vitamin D3, higher fasting glucose, higher cystatin C, higher NT-proBNP, and accelerated epigenetic aging. The biomarkers explained between 2% and 10% of subjective age and between 1% and 8% of SPA associations with memory. Additional analysis revealed that biomarkers continued to be significant mediators when physical inactivity and depressive symptoms were included as additional mediators.

CONCLUSION

The present study adds to existing research on the association between subjective aging and memory by providing new evidence on the biological mediators of this association.

Lower serum cystatin C level predicts poor functional outcome in patients with hypertensive intracerebral hemorrhage independent of renal function

We explored the association between the serum level of cystatin C (CysC) at admission and short-term functional outcome in patients with hypertensive intracerebral hemorrhage (HICH) without chronic kidney disease (CKD). A total of 555 patients with HICH were consecutively recruited after admission and were followed-up for 3 months after admission. The primary outcome was poor functional outcome (modified Rankin Scale [mRS] score ≥ 3). The median serum CysC level in our cohort was 1.03 mg/L (interquartile range, .89-1.20). Patients were categorized into four groups according to the serum CysC quartiles. Multivariate logistic regression analysis revealed a negative association between serum CysC and poor functional outcome at 3-month follow-up (quartile [Q]1 vs. Q4: adjusted odds ratio [OR] = .260, 95% confidence interval [CI] = .098, .691, p < .001). The negative association between serum CysC and poor functional outcome at 3 months was more pronounced in subgroups with smaller hematoma volume (≤ 30 mL), and absence of secondary intraventricular hemorrhage (IVH). Addition of serum CysC to a model containing conventional risk factors improved the model performance with net reclassification index (NRI) of .426% (p < .001) and integrated discrimination improvement (IDI) of .043% (p < .001) for poor functional outcome. Serum CysC was found to be a negative predictor of poor short-term functional outcome in HICH patients independent of renal function.

Vitamin D as predictor Marker of kidney disease in males with type 2 diabetes mellitus

The current work was done to determine the correlation between vitamin D and cystatin C as a predictor of kidney disease in males with diabetes mellitus. A total of 60 males were taken from October to December 2018. They were divided into 30 patients with type 2 diabetes and 30 healthy volunteers' as a control group. Glycated hemoglobin HbA1c, plasma glucose level, creatinine and urea were measured for all subjects. Also, levels of 25(OH) D and cystatin-c were determined using the enzyme-linked immune sorbent assay method. In this current study, as expected, patients with diabetes mellitus had significantly higher (p< 0.001) fasting blood glucose (FBG), body mass index (BMI), and glycated hemoglobin (HbA1c) levels as compared to the age-matched controls group. In addition, a significantly higher increase in the average level of urea, creatinine, and cystatin-c while significant higher decreases in vitamin D concentration compared to the patients group with the control group were found. A significant negative correlation was found between 25(OH) D and urea levels. On the other hand, a significant positive correlation was observed between the 25(OH) D level and HbA1c, FBG, cystatin-c and creatinine. From the results of this work, vitamin D could be a valuable predictor of nephropathy in males with diabetes mellitus. Likewise, further work is required to suggest that vitamin D may be prone to nephropathy in all patients with diabetes mellitus by estimating cystatin C as a clinical risk for kidney function. Keywords: Nephropathy, cystatin C, vitamin D.

A Preliminary Study on the Relationship between Serum Heparan Sulfate and Cancer-Related Cognitive Impairment: The Moderating Role of Oxidative Stress in Patients with Colorectal Cancer

Cancer-related cognitive impairment (CRCI) has been frequently reported in colorectal cancer survivors. Heparan sulfate (HS) was gradually considered to be related to cognitive disorders. The effect and potential mechanism of HS on CRCI in colorectal cancer patients were unexplored. In this study, all participants were divided into a cognitive impaired group and a cognitive normal group. The concentrations of oxidative stress factors and HS in serum were detected. Associations among HS, oxidative stress factors and CRCI were evaluated. Participants with cognitive impairment exhibited increased levels of HS, GSH, SOD and MDA, compared to the patients with normal cognitive performance. The independent significant association was found between HS and CRCI after controlling for various covariates. The higher concentrations of HS were related to the decreased cognitive performance among survivors who reported higher levels of GSH (β = 0.080, p = 0.002). Moreover, the nonlinear association between the level of HS and cognitive scores was confirmed using the restricted cubic splines (p < 0.001). These results indicated that the increased concentrations of circulating HS had a nonlinear negative connection with cognitive performance in colorectal cancer survivors, which was moderated by GSH. HS might be a new biomolecule for the identification and management of patients with CRCI.

Psychological Predictors of Perceived Age and Chronic Pain Impact in Individuals With and Without Knee Osteoarthritis

OBJECTIVE

Chronological age is a risk factor in chronic pain; however, aging research supports the premise that physical and psychological health may better predict perceived age. Given the lack of evidence on perceived age in the context of chronic pain, the current study presents novel findings about the relationship between perceived age, chronic pain impact, and psychological function in adults with and without knee osteoarthritis.

METHODS

This secondary analysis was part of an ongoing multisite observational cohort study to understand the progression of knee pain and disability. Community-dwelling adults (N=227) ages 45+ completed measures of trait resilience, trait positive and negative affect, pain catastrophizing, subjective perceptions of age, and the Graded Chronic Pain Scale.

RESULTS

On average, participants reported feeling 10 years younger than their chronological age; however, this effect was attenuated in individuals reporting high-impact pain. Lower perceived age was associated with lower pain impact (low pain/low disability), while higher perceived age correlated with higher pain impact (high pain/high disability) and more adverse psychological effects. Using hierarchical linear regression, high-impact pain and positive affect emerged as statistically significant predictors of perceived age, whereas no differences were observed among trait resilience, negative affect, or pain catastrophizing.

DISCUSSION

These findings highlight the importance of a biopsychosocial approach in understanding the intersection between psychological and physical factors associated with chronic pain. Addressing negative self-perceptions of aging, while simultaneously augmenting positive affect, through psychological therapies may mitigate pain and disability.

Feeling Younger in Rural Burkina Faso: Exploring the Role of Subjective Age in the Light of Previous Research from High Income Countries

Objectives

Previous research on subjective age (SA), that is, how young or old a person feels relative to their chronological age, has shown that older adults tend to feel younger than they are (by about 15%–20%), but the extent of this effect depends, in part, on their health. However, as most of the studies have been conducted in Western countries, it is unclear how well these results generalize to culturally different samples. Objectives, therefore, were to examine SA in middle-aged and older adults from a very low-income setting in rural Burkina Faso, to examine associations between SA and health/quality of life-related measures, and to compare findings with Western studies.

Methods

Representative, cross-sectional sample of N = 3,028 adults (≥40 years, recruited in 2018) from north-western Burkina Faso. Data included questionnaires on depression (Patient Health Questionnaire-9) and quality of life (World Health Organization Quality of Life scale, including subjective health) as well as performance-based and objective health-related measures (Community Screening Instrument for Dementia as cognitive screening, walking speed).

Results

Respondents felt on average 3% younger (SD = 0.13) than their chronological age, with 48% (95% confidence interval: 0.46–0.50) feeling younger—27 percentage points lower than seen in representative Western studies. Lower depression, better walking speed, cognition, and quality of life were all associated with younger SA.

Discussion

Middle-aged and older adults in Nouna felt less young than similar age groups in Western studies. One of the reasons may be that youthfulness is less of a value outside Western cultures. As in Western studies, parts of the variation in SA can be explained by health parameters.

Aging in Context: Incorporating Everyday Experiences Into the Study of Subjective Age

The age that a person feels is a strong predictor of their well-being and long-term health, beyond chronological age, showing that people have a self-awareness that provides insight into their aging process. It appears this insight has broad implications for a person's everyday life and functioning. One's subjective age is shaped by metacognitive beliefs about aging, including both expectations about typical changes but most notably the awareness and interpretation of personal experiences. Subjective age has been described as multidimensional, aligning with life domains such as cognitive, social, and physical functioning. This perspective, coupled with laboratory studies that manipulate subjective age, suggests that situational context has an important role in determining the age a person feels. Here we review literature on subjective age with a focus on how research and theoretical perspectives should be adapted to integrate momentary experiences. We propose a contextual model that will help discriminate the links between situational influences and subjective age, as well as resulting behaviors that impact health and well-being. While most research has considered subjective age to be a relatively stable variable, we provide a novel account of how daily life offers a variety of situational contexts and experiences that directly impact the age a person feels at a given moment. We propose that studying moment-to-moment context is a critical next step in understanding the associations between subjective age, lifestyle choices, and health outcomes.

Does older subjective age predict poorer cognitive function and higher risk of dementia in middle-aged and older adults?

As a biopsychosocial marker of aging, subjective age (i.e., the age individuals feel regardless of their actual age) was related to many health issues in the elderly. The purpose of this study is to investigate whether subjective age is associated with subsequent cognition and dementia risk in middle-aged and older adults. Samples were drawn from the English Longitudinal Study of Ageing (ELSA). Participants reported their subjective ages at the baseline (2004/2005), and their cognitive functions were measured after 10 years (2014/2015). Newly diagnosed dementias were recorded between 2006/2007 to 2014/2015. Overall, 6,475 adults aged 50 years or older were included in the current analyses. The relationship between subjective age reported at baseline and cognition assessed ten years later was modeled using multiple linear regression models. Compared to participants who reported a younger subjective age, those who reported an older subjective age were more likely to have poorer cognition after ten years (β = -0.705, P = .002 for memory, β = -1.567, P = .001 for executive function). A Cox proportional hazard regression model suggested that older subjective age was an independent risk factor for incident dementia (HR = 1.737, 95% CI =1.060-2.848). Other than chronological age, subjective age could also be considered as an important predictor for the development of cognitive dysfunction.

Prognostic Value of Pretreatment Serum Cystatin C Level in Nasopharyngeal Carcinoma Patients in the Intensity-modulated Radiotherapy Era

Purpose

Serum cystatin C has been considered as a significant prognostic factor for various malignancies. This study aimed to evaluate the relationship between serum cystatin C level before antitumor treatment and the prognosis of nasopharyngeal carcinoma (NPC) patients treated with intensity-modulated radiotherapy (IMRT).

Patients and Methods

A cohort of 2077 NPC patients were enrolled between April 2009 and September 2012. The Kaplan–Meier curves and log rank tests were used to determine the differences of overall survival (OS) and disease-free survival (DFS). Univariate and multivariate Cox regression analyses were used to determine independent prognostic factors.

Results

Overall, 362/2077 (17.4%) patients had high serum cystatin C level, and they were older and more male (both P<0.001), and they had higher TNM stage (all P<0.05). Kaplan–Meier analysis revealed that patients with high serum cystatin C had worse OS (P<0.001) and DFS (P<0.001). Univariate and multivariate Cox regression analysis showed that high serum cystatin C level was an independent prognostic predictor of OS (HR: 1.56, 95%CI: 1.25–1.95) and DFS (HR: 1.38, 95%CI: 1.13–1.68). Subgroup analysis based on TNM stage revealed that advanced-stage NPC patients with high serum cystatin C had poorer OS (P<0.001) and DFS (P<0.001).

Conclusion

Our results revealed that high serum cystatin C level before antitumor treatment can predict clinical outcomes of NPC patients treated with IMRT, and it can guide clinicians to formulate more personalized therapy for NPC patients.

PsychoAge and SubjAge: development of deep markers of psychological and subjective age using artificial intelligence

Aging clocks that accurately predict human age based on various biodata types are among the most important recent advances in biogerontology. Since 2016 multiple deep learning solutions have been created to interpret facial photos, omics data, and clinical blood parameters in the context of aging. Some of them have been patented to be used in commercial settings. However, psychological changes occurring throughout the human lifespan have been overlooked in the field of “deep aging clocks”.

In this paper, we present two deep learning predictors trained on social and behavioral data from Midlife in the United States (MIDUS) study: (a) PsychoAge, which predicts chronological age, and (b) SubjAge, which describes personal aging rate perception. Using 50 distinct features from the MIDUS dataset these models have achieved a mean absolute error of 6.7 years for chronological age and 7.3 years for subjective age. We also show that both PsychoAge and SubjAge are predictive of all-cause mortality risk, with SubjAge being a more significant risk factor.

Both clocks contain actionable features that can be modified using social and behavioral interventions, which enables a variety of aging-related psychology experiment designs. The features used in these clocks are interpretable by human experts and may prove to be useful in shifting personal perception of aging towards a mindset that promotes productive and healthy behaviors.

Views on aging: older adults' self-perceptions of age and of health

Perceptions of age and perceptions of health have each been found to predict future health and well-being, yet surprisingly, studies typically focused on one or the other. Studies on perceived age suggested that its effects on longevity may be mediated by perceived health. Within each of these lines of research, the constructs have not been consistently operationalized, making it difficult to generalize across studies. We aimed to investigate the associations of different measures of perceptions of age and of health with one another and with longevity. Data collected at baseline from the 851 participants of the Rutgers Aging and Health longitudinal study (mean age 73) included perceptions of age and health, each assessed with four different single-item measures, sociodemographic, and health measures. Mortality was followed-up for 10 years. All four health perceptions and two of the age perceptions (Age-group identity and nearness-to-death) were associated with survival time. Age and health perceptions had similar independent effects in models that included measures of both types, controlling for demographics and chronic conditions, though not after controlling for age. In contrast with our hypothesis, health perceptions did not mediate the association between age perceptions and mortality. Findings regarding health perceptions were generally consistent across measures, whereas age perception measures differed in their associations with various outcomes, indicating that they assess different subjective age constructs. The findings correspond with proposed explanations for the predictive effect of age and health perceptions and support the significant though weaker independent effects of age perceptions compared with health perceptions.

Physical activity and subjective age across adulthood in four samples

The present study examined the prospective association between physical activity and subjective age across adulthood and factors that mediate this association. Participants were adults aged from 20 to 90 years (N > 10,000) drawn from the Wisconsin Longitudinal Study graduates and siblings samples, the Health and Retirement Study and the Midlife in the United States Survey. In the four samples, physical activity was assessed at baseline and subjective age was measured 8 to 20 years later. Personality, self-rated health, disease burden, depressive symptoms, and cognition were assessed as potential mediators. In the four samples, higher physical activity at baseline was associated with a younger subjective age at follow-up. Logistic regression revealed that physical activity was related to a 30-50% higher likelihood of feeling younger 8 to 20 years later. Significant indirect effects were found through openness to experience and self-rated health in the four samples. This study provides new evidence on the link between a health-related behavior and subjective age. Physically active individuals may sustain health and an open psychological disposition that is associated with feeling younger.

Psychological aging, depression, and well-being

Aging is a multifactorial process, which affects the human body on every level and results in both biological and psychological changes. Multiple studies have demonstrated that a lower subjective age is associated with better mental and physical health, cognitive functions, well-being and satisfaction with life. In this work we propose a list of non-modifiable and modifiable factors that may possibly be influenced by subjective age and its changes across an individual's lifespan. These factors can be used for a future development of individual psychological aging clocks, which may be utilized as a sensitive measure for health status and overall life satisfaction. Furthermore, recent progress in artificial intelligence and biomarkers of biological aging have enabled scientists to discover and evaluate the efficacy of potential aging- and disease-modifying drugs and interventions. We propose that biomarkers of psychological age, which are just as important as those for biological age, may likewise be used for these purposes. Indeed, these two types of markers complement one another. We foresee the development of a broad range of parametric and deep psychological and biopsychological aging clocks, which may have implications for drug development and therapeutic interventions, and thus healthcare and other industries.

Concurrent and enduring associations between married partners' shared beliefs and markers of aging

Beliefs about aging are grounded in social experience. This study considered the extent to which married older adults' shared beliefs about aging and markers of aging maintain a concurrent and enduring association with their partners' beliefs about and markers of aging. Data from the 2010/2012 and 2014/2016 waves of the Health and Retirement Study provided measures of husbands' and wives' (3,779 couples) positive and negative beliefs about aging and internal (Cystatin C) and external (grip strength) markers of aging at 2 time points. Latent dyadic models parsed beliefs and markers into partners' individual and shared variances, which were connected both cross-sectionally and longitudinally. Longitudinal analysis showed that the cross-sectional associations between shared beliefs and markers of aging were stable over 4 years. Partners' shared beliefs and markers of aging were found to have enduring associations with each other over time. The enduring association between grip strength and future negative beliefs remained significant after accounting for partner selection and similarity in health. Model comparisons across marriage duration and emotional closeness showed partners' beliefs to be more similar in marriages that were either long established or emotionally close. In all groups, shared beliefs and markers of aging were associated with each other over time. The association between positive beliefs and future grip strength was stronger in long-established than in recent marriages. In summary, this study provides evidence that, within older couples, beliefs about aging are shaped in part through experiences of aging together. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Cystatin C promotes cognitive dysfunction in rats with cerebral microbleeds by inhibiting the ERK/synapsin Ia/Ib pathway

Although higher serum level of cystatin C (CysC) was observed in patients with cerebral microbleeds, its associated role in the disease has not been elucidated. In this work, a rat model of cerebral microbleeds was created with the aim of investigating effects of CysC on cognitive function in rats with cerebral microbleeds and the underlying mechanism. Serum samples of patients with cerebral microbleeds and healthy people of the same age were collected. Levels of cystatin C expression in these samples were measured using CysC kits. Moreover, 48 spontaneously hypertensive rats (SHRs) bred under specific pathogen-free (SPF) conditions were randomly divided into 4 groups: sham surgery control group (sham), model group (CMB), model + empty vector control group (CMB + vehicle), and model + cystatin C overexpression group (CMB + CysC). Expression levels of CysC in hippocampus of rats in each group were measured by western blot analysis. The Y-maze was used to evaluate cognitive function of rats. Hippocampal long-term potentiation (LTP) in rats was assessed by the electrophysiological assay. Alterations in levels of p-ERK1/2 and p-synapsin Ia/b proteins associated with cognitive function were identified by western blot analysis. The serum levels of CysC in patients with cerebral microbleeds were significantly upregulated (P<0.001). After injection of CysC, its expression levels in rat hippocampus were significantly increased (P<0.001), which enhanced the decline in learning and memory function, as well as the decrease of LTP in the rat model of cerebral microbleeds (P<0.001). Western blot results showed that injection of CysC further reduced the levels of p-ERK1/2 and p-synapsin Ia/b in the rat model of microbleeds (P<0.001). CysC was up regulated in serum of patients with cerebral microbleeds. It promoted cognitive dysfunction in rats with microbleeds by inhibiting ERK/synapsin Ia/Ib pathway.

How Does Subjective Age Get "Under the Skin"? The Association Between Biomarkers and Feeling Older or Younger Than One's Age: The Health and Retirement Study

Background and Objectives

Though subjective age is a well-recognized risk factor for several chronic diseases, the biological basis for these associations remains poorly understood.

Research Design and Methods

We used new comprehensive biomarker data from the 2016 wave of the nationally representative Health and Retirement Study (HRS) to evaluate the association between biomarker levels and self-reported subjective age in a subset of 3,740 HRS participants who provided a blood sample. We measured biomarkers in seven biological domains associated with aging: inflammation, glycemia, lipids, liver function, endocrine function, renal function, and cardiac function. The primary outcome was the age discrepancy score (subjective age − chronological age) categorized as those who felt younger, older, or the same as their chronological age (reference group). Analyses adjusted for comprehensive psychosocial factors (chronic stress index, depression score), demographic factors (race, sex, body mass index, marital status, physical activity), and prevalence of chronic health conditions (comorbidity index).

Results

The prevalence of clinically relevant reduced levels of albumin concentrations was lower in those who felt younger (8.8% vs. 16.0%; p = .006) and higher in those who felt older (20.4% vs. 16.0%; p = .03) when compared with the reference category. The prevalence of clinically significant elevation in liver enzymes such as alanine aminotransferase was also significantly lower among those who felt younger (7.1% vs. 8.6%; p = .04) when compared with the reference category. Prevalence of clinically elevated levels in cystatin C was also lower among those who felt younger when compared with the reference category (50.0% vs. 59.1%; p = .04). There was no association between lipids, glucose, or C-reactive protein (inflammatory marker) and subjective age categories.

Discussion and Implications

These results suggest that people who feel younger may have favorable biomarker profiles and as a result may have lower prevalence of age-related diseases when compared with those who feel older or those who feel the same as their chronological age.

Subjective Age as a Moderator in the Reciprocal Effects Between Posttraumatic Stress Disorder Symptoms and Self-Rated Physical Functioning

It is now widely acknowledged that physical decline may increase among middle-aged and older adults who suffer from posttraumatic stress disorder (PTSD). Much less is known about the temporal sequencing of PTSD and physical decline relationship over time. While PTSD can lead to physical decline, physical decline may preserve or augment existing PTSD symptoms. Both problems can also mutually affect each other forming a vicious cycle. Additionally, it is important to address variables that can mitigate these longitudinal effects. Following the recovery capital framework, we consider how the existence or lack of capital in the form of young age identity may affect the recovery process. Therefore, the current study aimed to examine the reciprocal effects of PTSD symptoms and self-rated physical functioning and further test whether one's subjective age moderates these effects. Using in-region random digit dialing, we collected a stratified sample of community dwelling older adult residing in south Israel. Of that sample (N at T1 = 339), 132 older adults (age range = 51-88, mean age = 66.90, SD = 9.14) were interviewed 4 months after the 2014 Israel-Gaza conflict (T2) and 1 year later (T3). Participants responded to PTSD symptoms scale, and reported their physical functioning and subjective age. PTSD symptoms and self-rated physical functioning were tested as both predictors and outcomes in a cross-lagged model. The moderating effect of subjective age was assessed by examining whether T2 variables interacted with subjective age in predicting T3 outcomes. Results showed that higher PTSD symptoms at T2 were associated with subsequent lower self-rated physical functioning at T3, yet self-rated physical functioning at T2 did not predict PTSD symptoms at T3, thereby highlighting the PTSD self-rated physical function direction. Moreover, subjective age moderated this latter association, so that this relationship was significant only for those who felt relatively older. In addition to clarifying the temporal sequencing of the PTSD self-rated physical functioning association, the study further suggests that an older subjective age (i.e., lack of recovery capital) could render middle-aged and older adults more susceptible to physical decline following PTSD symptoms. We therefore propose to develop interventions aimed at coping with an older age identity and facilitating a younger age identity among traumatized older individuals.