Cross-Sectional and Longitudinal Associations between Peak Expiratory Flow and Frailty in Older Adults

Association of peak expiratory flow with motoric cognitive risk syndrome among older adults

Background

The association between lung function and motoric cognitive risk syndrome (MCR) is unclear. We aimed to explore the association of peak expiratory flow (PEF) with MCR using cross-sectional and longitudinal analyses.

Methods

Within the CHARLS, 5095 participants were included in the cross-sectional analysis, and 4340 MCR-free participants were included in the longitudinal analysis. The PEF was assessed with a lung peak flow meter. MCR was characterized by cognitive complaints and a slow walking speed with normal mobility and without dementia. Logistic regression, Cox regression, and Laplace regression models were employed for data analysis.

Results

In this cross-sectional study, logistic regression analyses revealed that continuous PEF was associated with MCR (odds ratio [OR], 0.998; 95% confidence interval [CI], 0.998, 0.999), and the ORs (95% CIs) of MCR prevalence were 0.857 (0.693, 1.061) for the middle tertile and 0.665 (0.524, 0.845) for the highest tertile compared to the lowest tertile. In a longitudinal cohort study, continuous PEF was dose-dependently associated with the risk of MCR. Compared with those in the lowest tertile of PEF, the hazard ratios (95% CIs) of incident MCR were 0.827 (0.661, 1,036) for the middle tertile and 0.576 (0.432, 0.767) for the highest tertile. Furthermore, compared with the lowest tertile, the highest tertile was associated with a delayed onset time of MCR of 0.484 (95% CI: 0.151, 0.817) years.

Conclusion

A higher PEF was related to a lower prevalence of MCR and a lower risk for MCR, and a higher PEF also prolonged the onset time of MCR.

Lung function in relation to brain aging and cognitive transitions in older adults: A population-based cohort study

BACKGROUND

We investigated the association of peak expiratory flow (PEF) with dementia; cognitive impairment, no dementia (CIND); and transition from CIND to dementia, and possible underlying neuropathological mechanisms.

METHODS

A population-based cohort of adults aged 60+ was followed over 15 years to detect dementia (Diagnostic and Statistical Manual of Mental Disorders, 4th edition criteria), CIND (assessed through a cognitive battery), and progression from CIND to dementia, in relation to baseline PEF observations. A subsample (n = 462) had 6-year follow-up data on brain magnetic resonance imaging markers of neurodegeneration and small vessel disease.

RESULTS

In fully adjusted models, poor PEF performance (< 10th vs. ≥ 80th percentile) was associated with increased hazards for dementia (hazard ratio [HR] = 1.89; 95% confidence interval [CI] = 1.23-2.92) and CIND (HR = 1.55; 95% CI = 1.01-2.38) and CIND progression to dementia, although not statistically significantly (HR = 2.44; 95% CI = 0.78-6.88). People with poor PEF also experienced the fastest ventricular enlargement (β coefficient = 0.67 mL/year; 95% CI = 0.13-1.21) and had the highest likelihood of developing lacunes (odds ratio = 5.05; 95% CI = 1.01-25.23).

DISCUSSION

Poor lung function contributes to cognitive deterioration possibly through accelerated brain atrophy and microvascular damage.

HIGHLIGHTS

Poor lung function increased the risk of dementia and mild cognitive impairment (MCI). Poor lung function accelerated the progression from MCI to dementia. Poor lung function was linked to brain microvascular damage and global brain atrophy.

Associations between peak expiratory flow and frailty in olderly individuals: findings from the China health and retirement longitudinal study

Purpose

Peak Expiratory Flow (PEF) is associated with a variety of adverse health outcomes in older adults; however, the relationship between PEF and frailty remains uncertain, and this study investigated the relationship between PEF and frailty within an olderly Asian demographic.

Methods

Data were sourced from the Chinese Health and Retirement Longitudinal Study (CHARLS). Individuals in the study, all 60 years or older, underwent baseline PEF assessments quantified as standardized residual (SR) percentile values. The evaluation of frailty was conducted based on the criteria established by Fried. Participants without frailty at the outset were tracked over a four-year period, during which the relationships between PEF and frailty were examined through logistic regression and discrete-time Cox regression analyses.

Results

Among 5,060 participants, cross-sectional analysis revealed that the prevalence of frailty was 2-3 times higher in the lower 10-49th and < 10th SR percentile groups compared to the 80-100th SR percentile group. The longitudinal study corroborated these results, showing an adjusted hazard ratio (HR) of 2.01 (95% CI, 1.15-3.51) for PEF SR percentiles below the 10th, in contrast to those between the 80th and 100th percentiles.

Conclusion

PEF independently predicts and determines frailty in older adults. Declines in PEF greater than expected are associated with the development of frailty. Subsequent studies are encouraged to delve deeper into the connection between respiratory function and frailty in diverse contexts.

Association between physical activity, peak expiratory flow, and cognitive function in aging: a cross-sectional analysis

BACKGROUND

The aging global population is experiencing escalating challenges related to cognitive deficits and dementia. This study explored the interplay between pulmonary function, physical activity, and cognitive function in older U.S. adults to identify modifiable risk factors for cognitive decline.

METHODS

Utilizing NHANES 2011-2012 data, we conducted a cross-sectional analysis of 729 participants aged ≥ 60 years. Cognitive function, peak expiratory flow (PEF), and physical activity were assessed. Weighted logistic regression and mediation analyses were employed to examine associations.

RESULTS

The sample size was 729 (weighted mean [SD] age, 67.1 [5.3] years; 53.6% female participants). Preliminary correlation analysis indicated a positive correlation between the global cognitive score and physical activity (β = 0.16; p < 0.001), recreational activity (β = 0.22; p < 0.001), and PEF in percent predicted (PEF%) (β = 0.18; p < 0.001). Compared to those with a PEF% >100%, the PEF% (80-100%) group (OR, 2.66; 95% CI, 1.34-5.29; p = 0.005) and PEF% <80% group (OR, 3.36; 95% CI, 1.67-6.76; p = 0.001) were significantly associated with higher cognitive deficits risk. Recreational activity meeting guidelines was linked to a lower risk of cognitive deficits (OR, 0.24; 95% CI, 0.10-0.57; p = 0.001). Mediation analysis demonstrated that PEF mediates the relationship between physical activity and cognitive function.

CONCLUSION

This study revealed significant associations between lower PEF, diminished physical activity, and increased cognitive deficits in elderly individuals. The results supported the hypothesis that pulmonary function may mediate the connection between activity and cognitive health, emphasizing the importance of respiratory health in cognitive aging. Recognizing these associations is crucial for clinical care and public health policy aiming to mitigate cognitive decline in aging populations. While these findings are intriguing, validation through longitudinal design studies is deemed necessary.

Lung function and the risk of frailty in the European population: a mendelian randomization study

BACKGROUND

Epidemiological evidence has suggested a relationship between lung function and frailty, but the precise nature of the causality remains unclear. In this study, we applied a two-sample Mendelian randomization (MR) analysis to determine the causal effects of lung function on frailty.

METHODS

Single nucleotide polymorphisms (SNPs) independently related (P ≤ 5E-08) to lung function, as identified by genome-wide association study (GWAS), were applied as instrumental variables (IV). The association with frailty index (FI) was investigated using summary-level data from the latest GWAS on FI (n = 175,226). Different statistical methods were employed to evaluate the causal estimates between lung function and FI. The pleiotropy, heterogeneity, and leave-one-out analysis were applied to confirm the stability of the MR estimates.

RESULTS

Using the random-effect inverse-variance weighted approach, genetically proxied forced expiratory volume in the first second (FEV1), ratio of FEV1 on forced vital capacity (FVC) [FEV1/FVC], and peak expiratory flow (PEF) were significantly and inversely associated with FI (FEV1, β = -0.08, P = 2.03E-05; FEV1/FVC, β = -0.06, P = 9.51E-06; PEF, β = -0.07, P = 4.09E-04) with good statistical power (99.7-100%). However, no significant association was observed between FVC and FI (β = -0.01, P = 0.681). Leave-one-out analysis showed that there was no single SNP driving the bias of the estimates. There was potential heterogeneity, but no obvious pleiotropy was founded in this MR study.

CONCLUSIONS

Our findings indicate that impaired pulmonary function is closely related to the risk of frailty. Enhancing lung function in the elderly population may contribute to the prevention of frailty to a certain extent.

Towards a consensus definition of allostatic load: a multi-cohort, multi-system, multi-biomarker individual participant data (IPD) meta-analysis

BACKGROUND

Allostatic load (AL) is a multi-system composite index for quantifying physiological dysregulation caused by life course stressors. For over 30 years, an extensive body of research has drawn on the AL framework but has been hampered by the lack of a consistent definition.

METHODS

This study analyses data for 67,126 individuals aged 40-111 years participating in 13 different cohort studies and 40 biomarkers across 12 physiological systems: hypothalamic-pituitary-adrenal (HPA) axis, sympathetic-adrenal-medullary (SAM) axis, parasympathetic nervous system functioning, oxidative stress, immunological/inflammatory, cardiovascular, respiratory, lipidemia, anthropometric, glucose metabolism, kidney, and liver. We use individual-participant-data meta-analysis and exploit natural heterogeneity in the number and type of biomarkers that have been used across studies, but a common set of health outcomes (grip strength, walking speed, and self-rated health), to determine the optimal configuration of parameters to define the concept.

RESULTS

There was at least one biomarker within 9/12 physiological systems that was reliably and consistently associated in the hypothesised direction with the three health outcomes in the meta-analysis of these cohorts: dehydroepiandrosterone sulfate (DHEAS), low frequency-heart rate variability (LF-HRV), C-reactive protein (CRP), resting heart rate (RHR), peak expiratory flow (PEF), high density lipoprotein cholesterol (HDL-C), waist-to-height ratio (WtHR), HbA1c, and cystatin C. An index based on five biomarkers (CRP, RHR, HDL-C, WtHR and HbA1c) available in every study was found to predict an independent outcome - mortality - as well or better than more elaborate sets of biomarkers.

DISCUSSION

This study has identified a brief 5-item measure of AL that arguably represents a universal and efficient set of biomarkers for capturing physiological 'wear and tear' and a further biomarker (PEF) that could usefully be included in future data collection.

Personality associations with lung function and dyspnea: Evidence from six studies

OBJECTIVE

The present study examined the association between Five Factor Model personality traits and lung function and dyspnea.

METHODS

Participants were middle aged and older adults aged 34-103 years old (N > 25,000) from the Midlife in the United States Study (MIDUS), the Health and Retirement Study (HRS), the English Longitudinal Study of Ageing (ELSA), the National Health and Aging Trends Survey (NHATS), and the Wisconsin Longitudinal Study graduate (WLSG) and sibling (WLSS) samples. Data on peak expiratory flow (PEF), dyspnea, personality traits, smoking, physical activity, body mass index (BMI), emotional/psychiatric problems, and demographic factors were obtained in each sample.

RESULTS

A meta-analysis indicated that higher neuroticism was related to lower PEF, higher risk of PEF less than 80% of predicted value, and higher risk of dyspnea. In contrast, higher extraversion and conscientiousness were associated with higher PEF, lower likelihood of PEF lower than 80% of the predicted value, and lower risk of dyspnea. Higher openness was related to higher PEF and lower risk of PEF less than 80%, whereas agreeableness was related to higher PEF and lower risk of dyspnea. Smoking, physical activity, BMI and emotional/psychiatric problems partially accounted for these associations. There was little evidence that lung disease moderated the association between personality and PEF and dyspnea.

CONCLUSIONS

Across cohorts, this study found replicable evidence that personality is associated with lung function and associated symptomatology.

Pulmonary Function as a Predictor of Frailty Syndrome in Community-Dwelling Older Adults

BACKGROUND AND PURPOSE

Diminished pulmonary function is associated with negative health outcomes and pulmonary impairment, and can be associated with frailty. The objectives of this study were to compare pulmonary function between frail, prefrail, and nonfrail older adults; to verify the association between pulmonary function and frailty syndrome; and to establish cut-off points for pulmonary function variables for predicting frailty.

METHODS

A cross-sectional study was conducted with 379 community-dwelling older adults of both sexes. Spirometry was used to measure pulmonary function criteria (forced vital capacity, FVC; forced expiratory volume in 1 second, FEV 1 ; and FEV 1 /FVC ratio). The presence of frailty was evaluated with Fried's frailty phenotype. Statistical analysis included a multinomial logistic regression model. Pulmonary function cut-off points for discriminating frailty syndrome were established through analysis of the receiver operating characteristic curves.

RESULTS AND DISCUSSION

The study participants were a median of 69.0 (64.0-74.0) years old, and 12.4% presented frailty while 58% presented prefrailty. Frail and prefrail older adults presented significantly lower median FVC and FEV 1 values-FVC = 1.89 L (1.45-2.31) and FEV 1 = 1.60 L (1.24-1.91); FVC = 2.07 L (1.62-2.67) and FEV 1 = 1.66 L (1.32-2.09), respectively-than nonfrail participants-FVC = 2.53 L (1.96-3.16) and FEV 1 = 2.01 L (1.54-2.43). The adjusted analysis indicated that FEV 1 (odds ratio [OR] = 0.63; 95% confidence interval [CI], 0.39-0.99) and the FVC (OR = 0.68; 95% CI, 0.48-0.96) were inversely associated with prefrailty and that FVC (OR = 0.52; 95% CI, 0.29-0.94) was associated with frailty. Cut-off points for prefrailty (FVC ≤2.3 L and FEV 1 ≤1.86 L) and frailty (FVC ≤2.07 L and FEV 1 ≤1.76 L) were established.

CONCLUSIONS

Pulmonary function was lower in frail and prefrail older adults than in their nonfrail peers. Frailty and prefrailty were inversely associated with pulmonary function. Cut-off points for FEV 1 and FVC for discriminating frailty were established and may allow pulmonary function to serve as an indicator of frailty in older adults.

Association of Peak Expiratory Flow with Cognitive Function in the Chinese Middle-Aged and Elderly Population: A 7-Year Longitudinal Study

BACKGROUND

Previous studies have shown that impaired pulmonary function may be associated with cognitive decline, posing the question of whether peak expiratory flow (PEF) % pred could present a modifiable risk factor.

OBJECTIVE

To assess the association between PEF% pred and future cognitive function among Chinese participants aged 45 years and above.

METHODS

Data came from four waves fielded by the China Health and Retirement Longitudinal Study. Cognitive function was assessed by a global cognition score. Multivariate linear regression models and generalized estimating equation (GEE) were used to investigate associations between PEF% pred and later cognitive function.

RESULTS

A total of 2,950 participants were eligible for the final data analysis. After adjustment for baseline cognition and potential confounders, the association remained statistically significant (β = 0.0057, p = 0.027). Domains with increases were focused on episodic memory (β= 0.0028, p = 0.048) and figure drawing (β= 0.0040, p = 0.028). But these associations were not found in women (β= 0.0027, p = 0.379). However, GEE suggested that the rates of decline in global cognition decreased by 0.0096 (p < 0.001) units per year as baseline PEF% pred increased by 1% in middle-aged and elderly individuals, regardless of sex. And higher baseline PEF% pred correlated with declined rates of decrease of in episodic memory, figure drawing, and Telephone Interview of Cognitive Status (TICS).

CONCLUSION

Higher baseline PEF% pred was significantly associated with slower cognitive decline in global cognition, episodic memory, figure drawing, and TICS in middle aged and elderly Chinese adults.

Frailty and chronic respiratory disease: the need for a multidisciplinary care model

Background.

Frailty is a state of increased vulnerability to various health stressors but little information is summarized about frailty in patients with specific chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and asthma.

Objective.

We aimed to describe the burden of frailty on patients with chronic respiratory disorders and to discuss the need for multidisciplinary care services.

Methods.

PubMed and Cochrane Central databases were systematically reviewed for studies reporting outcomes associated with frailty in COPD, IPF, and asthma. Electronic databases were searched for relevant articles published in English from 2010 up to July 2020. Appraisal was carried out based on the Hierarchy of Evidence Rating System and the GRADE guidelines.

Results.

A total of 31 articles met all inclusion criteria with 24 of them at level IV, 1 at level V, and 6 at level VI. Frailty is likely to negatively affect quality of life and to increase the risk of mortality, especially in elderly with COPD, IPF and asthma. Each disease has a particular effect on the balance between health status, respiratory impairment and frailty. A greater understanding of frailty phenotype across different ages, as well as in a range of long-term conditions, is of great necessity in both clinical and research settings. Limited conformity was observed between different methodologies and nature of chronic diseases studied, leading to a further difficulty to extract homogeneous information.

Conclusion.

Literature shows that frailty is prevalent in COPD, IPF, and asthma, after adjusting for shared risk factors. Our findings suggest that frailty should be approached as an entity per se’, in order to assess real mortality risk, alongside respiratory disease severity and the presence of comorbidities. Health care professionals need knowledge, skills and multidisciplinary collaboration to buffer the impact of frailty on everyday practice.

Reference Values and Related Factors for Peak Expiratory Flow in Middle-Aged and Elderly Chinese

Background: Peak expiratory flow (PEF), as an essential index used for screening and monitoring asthma, chronic obstructive pulmonary disease, and respiratory mortality especially in the elderly, is recommended for low-resource settings in low- and middle-income countries. However, few studies have focused on the reference of PEF in China, especially in middle-aged and elderly people. Thus, this study aimed to determine age- and sex-specific reference values of PEF in the middle-aged and elderly Chinese population. Methods: There were 8,914 participants who were included for risk factor analysis and 5,498 participants included for reference value analysis. The PEF was measured using a peak flow meter in liters per minute. The distributions of standardized PEF terciles stratified by sex and age were reported. Multiple linear regression analysis was used to determine the associations between risk factors and PEF. Results: The PEF was higher in men than women across all age subgroups. The value of PEF decreased with age in both men and women. Height, weight, handgrip strength, and residence in rural were positively associated with PEF. Age and smoking status were negatively associated with PEF significantly in both men and women (P < 0.05). The mean PEF values were 367.10 and 253.00 L/min for men and women, respectively. Meanwhile, the prevalence of low PEF was 3.94 and 3.32% for men and women, respectively. Conclusions: Age- and sex-specific centiles of standardized PEF for the middle-aged and elderly Chinese population were estimated. The reference values for low PEF could provide reference standards for epidemiological studies and clinical practices in the future. Interventions to improve lung functions or to prevent respiratory disease should be paid more attention to factors associated with PEF.

Portals to frailty? Data-driven analyses detect early frailty profiles

BACKGROUND

Frailty is an aging condition that reflects multisystem decline and an increased risk for adverse outcomes, including differential cognitive decline and impairment. Two prominent approaches for measuring frailty are the frailty phenotype and the frailty index. We explored a complementary data-driven approach for frailty assessment that could detect early frailty profiles (or subtypes) in relatively healthy older adults. Specifically, we tested whether (1) modalities of early frailty profiles could be empirically determined, (2) the extracted profiles were differentially related to longitudinal cognitive decline, and (3) the profile and prediction patterns were robust for males and females.

METHODS

Participants (n = 649; M age = 70.61, range 53-95) were community-dwelling older adults from the Victoria Longitudinal Study who contributed data for baseline multi-morbidity assessment and longitudinal cognitive trajectory analyses. An exploratory factor analysis on 50 multi-morbidity items produced 7 separable health domains. The proportion of deficits in each domain was calculated and used as continuous indicators in a data-driven latent profile analysis (LPA). We subsequently examined how frailty profiles related to the level and rate of change in a latent neurocognitive speed variable.

RESULTS

LPA results distinguished three profiles: not-clinically-frail (NCF; characterized by limited impairment across indicators; 84%), mobility-type frailty (MTF; characterized by impaired mobility function; 9%), and respiratory-type frailty (RTF; characterized by impaired respiratory function; 7%). These profiles showed differential neurocognitive slowing, such that MTF was associated with the steepest decline, followed by RTF, and then NCF. The baseline frailty index scores were the highest for MTF and RTF and increased over time. All observations were robust across sex.

CONCLUSIONS

A data-driven approach to early frailty assessment detected differentiable profiles that may be characterized as morbidity-intensive portals into broader and chronic frailty. Early inventions targeting mobility or respiratory deficits may have positive downstream effects on frailty progression and cognitive decline.

Respiratory Sarcopenia and Sarcopenic Respiratory Disability: Concepts, Diagnosis, and Treatment

The condition of muscle fiber atrophy and weakness that occurs in respiratory muscles along with systemic skeletal muscle with age is known as respiratory sarcopenia. The Japanese Working Group of Respiratory Sarcopenia of the Japanese Association of Rehabilitation Nutrition narratively reviews these areas, and proposes the concept and diagnostic criteria. We have defined respiratory sarcopenia as "whole-body sarcopenia and low respiratory muscle mass followed by low respiratory muscle strength and/or low respiratory function." Respiratory sarcopenia can be caused by various factors such as aging, decreased activity, undernutrition, disease, cachexia, and iatrogenic causes. We have also created an algorithm for diagnosing respiratory sarcopenia. Respiratory function decreases with age in healthy older people, along with low respiratory muscle mass and strength. We have created a new term, "Presbypnea," meaning a decline in respiratory function with aging. Minor functional respiratory disability due to aging, such as that indicated by a modified Medical Research Council level 1 (troubled by shortness of breath when hurrying or walking straight up hill), is an indicator of presbypnea. We also define sarcopenic respiratory disability as "a disability with deteriorated respiratory function that results from respiratory sarcopenia." Sarcopenic respiratory disability is diagnosed if respiratory sarcopenia is present with functional disability. Cases of respiratory sarcopenia without functional disability are diagnosed as "at risk of sarcopenic respiratory disability." Functional disability is defined as a modified Medical Research Council grade of 2 or more. Rehabilitation nutrition, treatment that combines rehabilitation and nutritional management, may be adequate to prevent and treat respiratory sarcopenia and sarcopenic respiratory disability.

Peak expiratory flow, walking speed and survival in older adults: An 18-year longitudinal population-based study

BACKGROUND

Peak expiratory flow (PEF) and walking speed (WS) have been proposed as indicators of robustness and are independent predictors of health-related outcomes. We aimed to investigate how the co-occurrence of respiratory and physical impairments changes as a function of age, and to quantify the association of the combination of low PEF and slow WS on survival in older people.

METHODS

This prospective study analyzes data from 2656 community-dwelling participants (age ≥ 60 years) from the SNAC-K study. At baseline, we assessed: (1) sociodemographic, lifestyle and medical data; (2) respiratory function, estimated through PEF and expressed as standardized residual (SR) percentile; and (3) WS at usual pace, categorized as no (>1.2 m/s), mild (0.8-1.2 m/s) and moderate-to-severe (<0.8 m/s) walking impairment. Participants' vital status over an 18-year follow-up was derived from registers. The association of different combinations of PEF and WS on median survival time was estimated through Laplace regression adjusted for potential confounders.

RESULTS

Respiratory and walking impairments co-occurred more frequently with increasing age. Among individuals with PEF SR-percentiles < 10th, the percentage of moderate-to-severe walking impairment was 12.1% in sexagenarians, 35.7% in septuagenarians, and 75-80% in the oldest old. The greatest reduction in median survival time (-5.4 [95%CI: -6.4; -4.4] years, p < 0.001) was observed among people with combined respiratory and moderate-to-severe walking impairments, compared with those with no dysfunctions, who had a median survival time of 17.4 (95%CI: 17.0; 17.8) years.

CONCLUSIONS

Impaired PEF and WS co-occur more frequently with advancing age, and their co-occurrence is associated with shorter survival.