Aging Population Research Articles

Informal Employment and High Burden of Out-of-Pocket Healthcare Payments among Older Workers: Evidence from Longitudinal Ageing Study in India.

India's economy is among the fastest growing in the world. However, a large share of informal workforce is a common characteristic of country's economy, comprises a significant portion of most of its labour markets. This workforce often receives low wages and lacks benefits such as strong social security and health coverage for all. The majority of healthcare spending in India is private. As India's population ages and the informal sector expands, it is expected that many of these workers will continue to work beyond the retirement age to bear their own healthcare costs due to lack of savings, pensions and the precarious nature of their employment. In this context, this study estimates the burden of Out-of-Pocket (OOP) payments on India's informal older workers compared to their formal counterparts, using data from the first wave of the nationally representative Longitudinal Ageing Study in India. According to estimates from the Two-part regression model, informal older workers pay, on an average, INR 1113 (p<0.01) and INR 55 (p<0.05) less than their formal counterparts for inpatient and outpatient care, respectively. However, probit regression models revealed that the burden of combined (both inpatient and outpatient) OOP payments exceeding (by 40%, 20%, and 10%) of their income is significantly higher among informal older workers compared to formal older workers. The study underscores the need for strengthening of universal health insurance schemes to ensure everyone has access to medical services without experiencing financial hardship. It also advocates for policies specifically tailored towards informal workers, considering their unique challenges with regard to livelihoods and healthcare security. In particular, this encompasses bolstering the existing social security and healthcare system, and related policies for ensuring financial security against OOP payments, especially for informal workers and all the population in general.

Incidence and Prevalence of Concussion in Denmark from 1999-2018: A Nationwide Cohort Study.

Concussion is a common diagnosis in emergency rooms, yet contemporary incidence and prevalence estimates are sparse and rely on self-reported data. A nationwide cohort study was conducted to provide up-to-date information, covering the entire Danish population from 1999 to 2018. Hospital contacts with a concussion diagnosis, including emergency room visits, hospital admissions, and outpatient contacts, were retrieved from the Danish National Patient Registry (DNPR), and incidence rates were age-standardized and stratified. The 20-year prevalence was defined as the percentage of Danes alive in 2018 who had experienced a concussion since 1999. The diagnostic codes used were the ICD-10 code S06.0 and a local Danish code for 'observation for concussion' (DZ033D). Additional data on activities related to concussion injuries were obtained from the Accident Analysis Group at Odense University Hospital through DNPR. Findings from the study indicated that during the period 1999-2018, the total age-standardized concussion incidence rate increased by 10% to 308 per 100,000 person-years (95% confidence interval (CI): 304-313). Notable time trends included 1) a reduced sex difference from 40% to 6% (95% CI: 3%-9%), 2) a doubled incidence rate in children aged 0-1 and in seniors aged over 80, 3) an increased utilization of head imaging across all age groups, except children, 4) a decline in the proportion of traffic-related concussions, and 5) a prevalence of concussion of 4.9% (95% CI: 4.89% - 4.93%) in 2018. The increasing incidence of concussions among the elderly is concerning in light of an aging population, and warrants further investigation, as evidence-based preventive interventions for falls exist. Additionally, the increased utilization of head imaging across all age groups except children calls for attention toward avoidance of unnecessary radiation exposure. Despite a drop in traffic-related cases, concussions remain highly prevalent. In conclusion, these findings indicate that concussions are an important public health concern, necessitating ongoing surveillance, research, and targeted resource allocation to address concussion management and prevention effectively.

A randomized controlled trial of acupuncture and receptive music therapy for sleep disorders in the elderly—ELAMUS: study protocol

BackgroundGlobally, the demographic shift towards an aging population leads to significant challenges in healthcare systems, specifically due to an increasing incidence of multimorbidity resulting in polypharmacy among the elderly. Simultaneously, sleep disorders are a common complaint for elderly people. A treatment with pharmacological therapies often leads to side effects causing a high potential for dependency. Within this context, there is a high need to explore non-pharmacological therapeutic approaches. The purpose of this study is to evaluate the effectiveness of acupuncture and music therapy, both individually and combined as a multimodal therapy, in the treatment of sleep disorders in individuals aged 70 years and older.MethodsWe conduct a confirmatory randomized controlled trial using a two-factorial study design. A total of n = 100 elderly people receive evidence-based standard care information for age-related sleep disorders. Beyond that, patients are randomly assigned into four groups of n = 25 each to receive acupuncture, receptive music therapy with a monochord, multimodal therapy with both acupuncture and music therapy, or no further therapy. The study’s primary outcome measurement is the improvement in sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI) (global score), at the end of intervention. Additionally, depression scores (Geriatric Depression Scale), health-related quality of life (Short-Form-Health Survey-12), neurovegetative activity measured via heart rate variability, and safety data are collected as secondary outcomes. Using a mixed-methods approach, a qualitative process evaluation will be conducted to complement the quantitative data.DiscussionThe study is ongoing and the last patient in is expected to be enrolled in April 2024. The results can provide valuable insights into the effectiveness of non-pharmacological interventions for sleep disorders among the elderly, contributing to a more personalized and holistic approach in geriatric healthcare.Trial registrationGerman Clinical Trials Register (DRKS00031886).

Mineral supplementation in patients with frailty and sarcopenia-a systematic review.

Addressing sarcopenia and frailty in aging populations is crucial for enhancing quality of life and reducing healthcare dependence. While the importance of energy, protein, and amino acid supplementation is known, the role of minerals needs further exploration. This systematic review evaluates the effectiveness of these minerals in managing sarcopenia and frailty. We analyzed data from the Cochrane Central Register of Controlled Trials, MEDLINE, and Ichu-shi Web from January 2000 to March 2023. Studies were selected if they were interventional or observational, focused on individuals with frailty or sarcopenia who were aged 65 or older, and involved mineral supplementation. The risk of bias in these studies was assessed using the Cochrane Risk of Bias 2 tool. Of the 615 studies identified, seven met the inclusion criteria. These studies mainly focused on the effects of combined nutrient supplements, with few focusing on individual minerals. The findings were mixed, demonstrating some improvements in muscle strength, activity of daily living, and cognitive functions. Notably, minerals appeared to offer benefits as part of multi-nutrient interventions, especially for cognitive and immune health, but had limited impact on muscle mass or strength when used alone. The limited number and variable outcomes of studies precluded a feasible meta-analysis. The effect of mineral supplementation on sarcopenia and frailty remains uncertain, suggesting a need for tailored nutritional strategies. Future studies should aim for well-designed clinical trials in order to gain a better understanding of the roles of minerals in improving muscle health and functional outcomes, leading to clearer recommendations for clinical practice. Geriatr Gerontol Int 2024; ••: ••-••.

Delay and Pay? Healthcare Costs Associated with Late Oral Anti-coagulant Prescribing in People with Atrial Fibrillation.

Atrial fibrillation (AF) is associated with increased morbidity and mortality and exerts an increasingly significant burden on global healthcare resources, with its prevalence rising with an ageing population. Despite a substantial thromboembolic risk, particularly in the period immediately following diagnosis, oral anti-coagulation is frequently not initiated or is delayed. The aim of this study was to evaluate healthcare costs in people with AF, comparing those who were commenced on oral anti-coagulation in the immediate period following the index diagnosis date with those in whom initiation was late and those who never started anti-coagulation. This retrospective cost analysis used linked Scottish health data to identify adults newly diagnosed with AF between January 1st 2012 and April 30th 2019 with a baseline CHA2DS2-VASc score of ≥2. This AF population was sub-divided according to timing of the first prescription of oral anti-coagulant (OAC) during a 2-year follow-up period: never started (OAC never initiated), immediate OAC (OAC prescribed within 60 days of incident AF diagnosis), and delayed OAC (OAC prescribed more than 60 days after incident AF diagnosis). A two-part model was developed, adjusted for key covariates, including age, sex, and frailty, to estimate costs for inpatient admissions, outpatient care, prescriptions, and care home admissions, and overall costs. Of an overall AF population of 54,385, 26,805 (49.3%) never commenced OAC, 7654 (14.1%) initiated an OAC late, and 19,926 (36.6%) were prescribed anti-coagulation immediately. The mean adjusted cost for the overall AF population was £7807 per person per year (unadjusted: £8491). Delayed OAC initiation was associated with the greatest adjusted estimated mean annual cost (unadjusted: £13,983; adjusted: £9763), compared to those that never started (unadjusted: £10,433; adjusted: £7981) and those that received an immediate OAC prescription (unadjusted: £3976; adjusted: £6621). Increasing frailty, mortality, and female sex were associated with greater healthcare costs. AF is associated with significant healthcare resource utilisation and costs, particularly in the context of delayed or non-initiation of anti-coagulation. Indeed, there exists substantial opportunity to improve the utilisation and prompt initiation in people newly diagnosed with AF in Scotland. Interventions to mitigate against the growing economic burden of AF should focus on reducing admissions to hospitals and care homes, which are the principal drivers of costs; prescriptions and outpatient appointments account for a relatively small proportion of overall costs for AF.

An ageing population: what does this mean for spousal carers and the person with dementia?

An ageing population: what does this mean for spousal carers and the person with dementia?

Dysphagia: causes, diagnosis and treatment – an update for practice nurses

The number of people with dysphagia is rising in line with population ageing. It is now thought to affect around 5.2 million people in the UK, one adult in 8 ( Boaden et. al, 2019 ). It becomes more common as people age and is associated with neurological problems, frailty and poor outcomes ( Patel et. al, 2018 : Cohen et. al, 2021 ). This article aims to update practice nurses on the clinical features of dysphagia, how to identify it, when to refer and how it is managed. As many as one adults in eight in the UK are affected by dysphagia. Linda Nazarko looks at what nurses need to know when managing this condition.

Internal medicine in the 21st century: Back to the future

Healthcare systems face multiple challenges arising from demographic factors (population aging) and epidemiological factors (rise of chronic diseases and patients with multimorbidity) as well as threats to their financial sustainability when maintaining equitable access to medical and technological advances. Current healthcare models, based on specialized medical care, lead to fragmented care that can be harmful to the patient and is inefficient for the system due to the overuse of redundant, low-value medical acts. Internal medicine is the hospital-centered general medical specialty par excellence, providing a comprehensive and holistic vision that is centered on the patient and not on the disease. Internists should be the leading physicians in the hospital setting for complex patients with or those with an uncertain diagnosis. Internists must play a key role, as hospitalists do, in the continued care of acute patients hospitalized for medical or surgical diseases, establishing shared care models in multidisciplinary teams. Likewise, to guarantee continuity of care for chronic patients, internists must establish mechanisms for collaboration with primary care and nursing, participating in the development of new out-of-hospital care models that use the available technological resources. Internal medicine should play a leading role in graduate and postgraduate medical education to promote a holistic vision among medical students and residents in medical subspecialties.

Toxoplasma infection induces an aged neutrophil population in the CNS that is associated with neuronal protection

BackgroundInfection with the protozoan parasite Toxoplasma gondii leads to the formation of lifelong cysts in neurons that can have devastating consequences in the immunocompromised. In the immunocompetent individual, anti-parasitic effector mechanisms and a balanced immune response characterized by pro- and anti-inflammatory cytokine production establishes an asymptomatic infection that rarely leads to neurological symptoms. Several mechanisms are known to play a role in this successful immune response in the brain including T cell production of IFNγ and IL-10 and the involvement of CNS resident cells. This limitation of clinical neuropathology during chronic infection suggests a balance between immune response and neuroprotective mechanisms that collectively prevent clinical manifestations of disease. However, how these two vital mechanisms of protection interact during chronic Toxoplasma infection remains poorly understood.Main textThis study demonstrates a previously undescribed connection between innate neutrophils found chronically in the brain, termed “chronic brain neutrophils” (CBNeuts), and neuroprotective mechanisms during Toxoplasma infection. Lack of CBNeuts during chronic infection, accomplished via systemic neutrophil depletion, led to enhanced infection and deleterious effects on neuronal regeneration and repair mechanisms in the brain. Phenotypic and transcriptomic analysis of CBNeuts identified them as distinct from peripheral neutrophils and revealed two main subsets of CBNeuts that display heterogeneity towards both classical effector and neuroprotective functions in an age-dependent manner. Further phenotypic profiling defined expression of the neuroprotective molecules NRG-1 andErbB4 by these cells, and the importance of this signaling pathway during chronic infection was demonstrated via NRG-1 treatment studies.ConclusionsIn conclusion, this work identifies CBNeuts as a heterogenous population geared towards both classical immune responses and neuroprotection during chronic Toxoplasma infection and provides the foundation for future mechanistic studies of these cells.

Machine learning in diagnostic support in medical emergency departments

Diagnosing patients in the medical emergency department is complex and this is expected to increase in many countries due to an ageing population. In this study we investigate the feasibility of training machine learning algorithms to assist physicians handling the complex situation in the medical emergency departments. This is expected to reduce diagnostic errors and improve patient logistics and outcome. We included a total of 9,190 consecutive patient admissions diagnosed and treated in two hospitals in this cohort study. Patients had a biochemical workup including blood and urine analyses on clinical decision totaling 260 analyses. After adding nurse-registered data we trained 19 machine learning algorithms on a random 80% sample of the patients and validated the results on the remaining 20%. We trained algorithms for 19 different patient outcomes including the main outcomes death in 7 (Area under the Curve (AUC) 91.4%) and 30 days (AUC 91.3%) and safe-discharge(AUC 87.3%). The various algorithms obtained areas under the Receiver Operating Characteristics -curves in the range of 71.8–96.3% in the holdout cohort (68.3–98.2% in the training cohort). Performing this list of biochemical analyses at admission also reduced the number of subsequent venipunctures within 24 h from patient admittance by 22%. We have shown that it is possible to develop a list of machine-learning algorithms with high AUC for use in medical emergency departments. Moreover, the study showed that it is possible to reduce the number of venipunctures in this cohort.

Decomposing the Drivers of Population Aging: A Research Note.

Population aging is an important and increasingly relevant area of study for demographers. A growing body of research seeks to determine how long-term changes in births, mortality, and migration-the three drivers of any demographic process-have shaped the present aging situation. Using variable-r decomposition and cohort data, this research note presents a formula for the change in the old-age dependency ratio to determine the extent to which relative changes in births, as well as in mortality and migration rates, contribute to aging. This perspective provides a careful and in-depth picture of aging and contributes to the debate concerning whether changes in births or mortality have had the strongest effect on population aging. When applied to Australia, the United States, and several European populations, the decomposition of the old-age dependency ratio shows that aging occurred in all populations and that changes in both births and mortality contributed to this aging. Analysis of these populations demonstrates that although they differed regarding which of these factors contributed more, changes in births prevailed as the more significant factor. In nearly all populations, migration decreased the rate of population aging.

Development and Validation of the Dementia Caregiver Burden Scale: A Tool for Community-Dwelling Dementia Caregiver.

The number of patients with dementia increases rapidly in aging populations. Dementia is an irreversible disease that causes a patient to be dependent on others' care and also causes family caregivers to experience difficulties in multiple domains. In this study, a dementia caregiver's burden scale that addresses family caregivers' characteristics and caring environments was developed and validated. In-depth interviews with nine caregivers were conducted to identify the attributes of perceived burden and establish preliminary questions. Content validity was confirmed by seven experts using the item content validity index and scale content validity index/average. Construct validity, criterion-related validity, and reliability were verified using data from 205 primary caregivers of patients with dementia. Exploratory factor analysis revealed that five factors, including physical health deterioration, responsibility and role of caregiver, emotional distress, medical expense concerns, and family conflict, and 24 items explained 68.6% of the total variance. The calculated Cronbach's α for the overall scale was .96. The scale developed in this study may be used to measure the burden perceived by family caregivers of patients with dementia in the physical, emotional, social, financial, and situational domains. Also, the scale may be used to guide the development of tailored interventions that take into consideration different family caregiver and caring situation-related characteristics.

State of the Art of Brain Function Detection Technologies in Robot-Assisted Lower Limb Rehabilitation.

Background: With an aging population, the prevalence of neurological disorders is increasing, leading to a rise in lower limb movement disorders and, in turn, a growing need for rehabilitation training. Previous neuroimaging studies have shown a growing scientific interest in the study of brain mechanisms in robot-assisted lower limb rehabilitation (RALLR). Objective: This review aimed to determine differences in neural activity patterns during different RALLR tasks and the impact on neurofunctional plasticity. Methods: Sixty-five articles in the field of RALLR were selected and tested using three brain function detection technologies. Results: Most studies have focused on changes in activity in various regions of the cerebral cortex during different lower limb rehabilitation tasks but have also increasingly focused on functional changes in other cortical and deep subcortical structures. Our analysis also revealed a neglect of certain task types. Conclusion: We identify and discuss future research directions that may contribute to a clear understanding of neural functional plasticity under different RALLR tasks.

Improving Health for Our Aging Population.

Improving Health for Our Aging Population.

Evaluate a comprehensive geriatric assessment service framework targeting frail older people who had high risk of requiring long-term care services in Japan: a community-based pilot study

BackgroundFrailty has become a key concern in an aging population. A comprehensive geriatric assessment (CGA) service framework was developed and evaluated aiming to target and connect frail older adults who are at high risk of requiring long-term care services.MethodsA community-based pilot study was conducted in fiscal year 2016 and 2017 in Kure city, Hiroshima, Japan. Participants aged 65 and over living in Kure city, and 393 persons were extracted from the Kihon Check List (KCL) responses. Among the eligible individuals, 101 consented to participate and received CGA and referred to services based on individual health needs. The efficacy was evaluated by referral rate of services, continuity of the service usage, evaluation of participant’s health condition and the quality of life (QoL) after the 6-month follow-up.ResultsNinety-nine (98.0%) participants needed support for the instrumental activity of daily living, 97 (96.0%) were categorized as locomotive syndrome, and 64 (63.4%) had a depressive tendency. Afterward, 60 participants (59.4%) subsequently accepted the referral services, however, 34 (33.7%) used the services and the remaining 26 (25.7%) did not use the services. The health condition improvements in the service-uses group were statistically significant (p < 0.001), however, QoL score did not change between the baseline and 6th -month.ConclusionKCL extracted high-risks older people, and CGA revealed related diseases and health conditions. However, the high refusal rate of referral services indicates a necessity to modify the service framework such as by collaborating with community general support centers, which could increase the efficacy of service framework.

Impact of PM2.5 exposure in old age and its interactive effect with smoking on incidence of diabetes

PurposeTo determine the impact of PM2.5 exposure in old age and its interactive effect with smoking on incident diabetes. MethodsA total of 2766 participants aged ≥60 years in China were interviewed at baseline for disease risk factors in 2001–03 and were then followed up for 10 years to document incident diabetes. They were assessed for daily PM2.5 exposure in 2005. Multivariate Cox regression models were used to examine the association of PM2.5 exposure with incident diabetes and interactive effect between PM2.5 and smoking on incident diabetes. ResultsDuring the cohort follow-up, 176 participants developed diabetes. The incidence of diabetes increased with PM2.5 exposure; the multiple-adjusted hazard ratio (HR) of diabetes was 2.27 (95 % CI 1.36–3.77) in participants with PM2.5 at ≥62.0 μg/m3 compared to those with <62.0 μg/m3. There was a significant interaction effect of PM2.5 with smoking on increased risk of diabetes. The adjusted HR for participants exposed to PM2.5 levels ≥62.0 μg/m3 who smoked was 4.39 (95 % CI 1.72–11.21), while for non-smokers it was 1.65 (95 % CI 0.88–3.09), compared to those with <62.0 μg/m3. ConclusionsExposure to PM2.5 in old age was associated with an increased incidence of diabetes and smoking enhanced the impact of PM2.5 on diabetic risk. These findings underscore the urgent need for air quality improvement measures and smoking cessation programs to mitigate the risk of diabetes in aging populations.

Calcium Pyrophosphate Crystal Formation and Deposition: Where Do we Stand and What Does the Future hold?

Although calcium pyrophosphate deposition (CPPD) has been known since the 1960s, our understanding of its pathogenesis remains rudimentary. This review aims to illustrate the known mechanisms underlying calcium pyrophosphate (CPP) crystal formation and deposition and explore future directions in research. By examining various perspectives, from basic research to clinical and imaging assessments, as well as new emerging methodologies, we can establish a starting point for a deeper understanding of CPPD pathogenesis. Recent years have seen significant advances in CPPD research, particularly in the clinical field with the development of the 2023 ACR/EULAR classification criteria for CPPD disease, and in imaging with the introduction of the OMERACT ultrasonographic definitions and scoring system. However, progress in basic research has been slower. New laboratory approaches, such as Raman spectroscopy and omics sciences, offer promising insights that may help piece together the puzzle of CPPD. CPPD is a common yet understudied condition. As the population ages and CPPD becomes more prevalent, there is an urgent need to better understand the disease and the mechanisms involved in crystal formation and deposition, in order to improve diagnosis and therapeutic approaches.

Longitudinal decline in peak V̇o2 with aging in a healthy population is associated with a reduction in peripheral oxygen utilization but not in cardiac output.

Aging is associated with a significant decline in aerobic capacity assessed by maximal exercise oxygen consumption (V̇o2max). The relative contributions of the specific V̇o2 components driving this decline, namely cardiac output (CO) and arteriovenous oxygen difference (A - V)O2, remain unclear. We examined this issue by analyzing data from 99 community-dwelling participants (baseline age: 21-96 yr old; average follow-up: 12.6 yr old) from the Baltimore Longitudinal Study of Aging, free of clinical cardiovascular disease. V̇o2peak, a surrogate of V̇o2max, was used to assess aerobic capacity during upright cycle ergometry. Peak exercise left ventricular volumes, heart rate, and CO were estimated using repeated gated cardiac blood pool scans. The Fick equation was used to calculate (A - V)O2diff,peak from COpeak and V̇o2peak. In unadjusted models, V̇o2peak, (A - V)O2diff,peak, and COpeak declined longitudinally over time at steady rates with advancing age. In multiple linear regression models adjusting for baseline values and peak workload, however, steeper declines in V̇o2peak and (A - V)O2diff,peak were observed with advanced entry age but not in COpeak. The association between the declines in V̇o2peak and (A - V)O2diff,peak was stronger among those ≥50 yr old compared with their younger counterparts, but the difference between the two age groups did not reach statistical significance. These findings suggest that age-associated impairment of peripheral oxygen utilization during maximal exercise poses a stronger limitation on peak V̇o2 than that of CO. Future studies examining interventions targeting the structure and function of peripheral muscles and their vasculature to mitigate age-associated declines in (A - V)O2diff are warranted.NEW & NOTEWORTHY The age-associated decline in aerobic exercise performance over an average of 13 yr in community-dwelling healthy individuals is more closely associated with decreased peripheral oxygen utilization rather than decreased cardiac output. This association was more evident in older than younger individuals. These findings suggest that future studies with larger samples examine whether these associations vary across the age range and whether the decline in cardiac output plays a greater role earlier in life. In addition, studies focused on determinants of peripheral oxygen uptake by exercising muscle may guide the selection of preventive strategies designed to maintain physical fitness with advancing age.

Association of dietary and lifestyle inflammatory indices with type 2 diabetes risk in Iranian adults

BackgroundType 2 diabetes mellitus (T2DM) is often linked to chronic inflammation, which can be influenced by both lifestyle and dietary choices. However, the relationship between the inflammatory potential of diet and lifestyle factors and the risk of developing T2DM remains unclear. The present study aimed to investigate the associations of the empirical dietary inflammatory index (EDII), dietary inflammatory score (DIS), and lifestyle inflammatory score (LIS) with the risk of T2DM among Iranian adults.MethodsThe current study was conducted on 5714 individuals from Yazd Health Study (YaHS) who were followed up for a mean period of six years. YaHS is a prospective cohort study which has been conducted since 2014. Dietary intakes were collected at baseline using the food frequency questionnaire. The relative risk (RR) of T2DM was calculated by Cox regression analysis across tertiles of EDII, DIS, and LIS, adjusted for potential confounders.ResultsThe mean ± SD for the age and body mass index of the study population were 47.0 ± 9.2 years and 26.7 ± 5.1 Kg.m2, respectively. A significant association between LIS and the risk of T2DM was observed (RR: 4.05, 95% CI: 2.61–6.27 P-trend < 0.001). Individuals in the highest compared to the lowest tertile of EDII-LIS (RR: 3.07, 95%CI: 2.01–4.68; P for trend < 0.001) and DIS-LIS (RR: 2.42, 95%CI: 1.69–3.49; P for trend < 0.001) had a higher risk of T2DM. However, no significant association was found between EDII and DIS scores and the risk of T2DM.ConclusionGreater adherence to LIS, EDII-LIS, and DIS-LIS scores was associated with a higher risk of T2DM, while no significant association was found between EDII and DIS with T2DM risk.

AGN populations in the local Universe: Their alignment with the main sequence, stellar population characteristics, accretion efficiency, and the impact of AGN feedback

In this study, we used a sample of 338 galaxies – within the redshift range of 0.02 &lt; z &lt; 0.1 drawn from the Sloan Digital Sky Survey (SDSS) – for which there are available classifications based on their emission line ratios. We identified and selected Compton-thick (CT) AGN through the use of X-ray and infrared luminosities at 12 μm. We constructed the spectral energy distributions (SEDs) for all sources and fit them using the CIGALE code to derive properties related to both the AGN and host galaxies. Employing stringent criteria to ensure the reliability of SED measurements, our final sample comprises 14 CT AGN, 118 Seyfert 2 (Sy2), 82 composite, and 124 low-ionization nuclear emission-line regions (LINER) galaxies. Our analysis reveals that, irrespective of their classification, the majority of the sources lie below the star-forming main sequence (MS). Additionally, a lower level of AGN activity is associated with a closer positioning to the MS. Using the Dn4000 spectral index as a proxy for the age of stellar populations, we observe that, compared to other AGN classes, LINERs exhibit the oldest stellar populations. Conversely, CT sources are situated in galaxies with the youngest stellar populations. Furthermore, LINER and composite galaxies tend to show the lowest accretion efficiency, while CT AGN, on average, display the most efficient accretion among the four AGN populations. Our findings are consistent with a scenario in which the different AGN populations might not originate from the same AGN activity burst. Early triggers in gas-rich environments can create high-accretion-rate supermassive black holes (SMBHs), leading to a progression from CT to Sy2, while later triggers in gas-poor stages result in low-accretion-rate SMBHs like those found in LINERs.