1.1. Introduction:

The objective was to conduct a systematic review of economic assessment of interventional strategies, in the prevention of frailty in elderly of 60 years and over living at home.

1.2. Methods:

The keywords were searched in databases such as PubMed, ScienceDirect, Google Scholar and Embase. Articles published in English and French between 31/10/2010 and 31/12/2021 were included. The CHEERS statement reading grid was used to assess the quality of the studies in terms of economic assessments.

1.3. Results:

The search had identified eleven relevant research studies, including nine randomised controlled trials and two quasi-experimental studies. Of these studies, we classified them into three programs: seven studies on frailty screening, three studies on falls prevention and one study on the analysis of drugs and treatments prescribed and delivered. According to the cost-effectiveness plan of these programs, four studies had no conclusion on economic results, three studies had a dominant strategy, less expensive and more effective and four studies had a dominated strategy, more expensive and not effective. Only 50% of the studies were of good quality.

1.4. Conclusion:

Only three studies had less expensive and more effective multidimensional and interdisciplinary intervention strategies. They improved the quality of life of vulnerable elderly. The economic results were more mixed for some studies. Many methodological weaknesses were present in these studies.

Frailty , Cost-effectiveness analysis, Cost-utility analysis ,Personalized care plan ,Elderly, Community-dwelling.

Kehoua G, Le Goff-Pronost M, Gayot C, Marie-Laure L, Druet-Cabanac M, et al. (2023) Economic Assessments of Intervention Strategies in the Prevention of Frailty for Elderly of 60 Years and over Living at Home: A Systematic Review. Ann Gerontol Geriatric Res 9(1): 1056

A demographic revolution is underway in the world. According to the World Health Organization (WHO), the absolute number of people aged 60 and over is expected to increase from 901 million in 2015, to 1.4 billion in 2030 and 2.1 billion in 2050, and could reach 3.2 billion in 2100 [1]. Today, a person aged 60 can expect to live, on average, 22 years longer, although there are considerable differences in longevity depending on the social and economic group to which the older people belong Worldwide, as in France, aging has a cost and today represents three quarters of social protection expenditure [2]. As people age, there is increasing prevalence of polypharmacy and geriatric syndromes, malnutrition, memory problems, depression, mental confusion, pressure sores, incontinence, repeated falls and frailty [3,4]. According to the French Society of Geriatrics and Gerontology, frailty is a clinical syndrome. It reflects a decrease in physiological reserve capacity which alters the mechanisms of adaptation to stress. Its clinical expression is modulated by comorbidities and psychological, social, economic and behavioural factors. The frailty syndrome is a risk marker for mortality and adverse events, including disabilities, falls, hospitalization and institutionalisation. Age is a major determinant of frailty but does not in itself explain this syndrome [5]. In the absence of a consensual definition, there are four types of conceptualizations of frailty can be distinguished: biomedical, bio-psychological, biopsycho-sociological and integrative models [6,7]. However, two main operational models, echoing the debate on the medical or geriatric syndrome, mark out the field of frailty measurement for older people [8]. It is measured mainly by two models: the Fried phenotype and the Rockwood index. Fried’s phenotype, considered a specific indicator of frailty, is a conceptual model or cycle of frailty, linking together its five dimensions and positioning frailty in relation to disease, functional deficits and external influences [9]. In contrast, the Rockwood model, considered as a global indicator of the health of the elderly, is the accumulation of deficits, and is based on the idea that frailty is measured by the number of age-related health problems, regardless of their nature and severity [10]. Considered as a major challenge of the 21st century, the interest of frailty is based on its roles as indicators of the risk of adverse events and possible loss of functional independence [11,12]. Addressing the determinants of frailty can reduce or delay its consequences. Thus, observed possibility of reversing frailty, in particular at an early stage, opens a real potential of preventive interventions, individual or collective, with the objectives of slowing down the poly-pathological progression that ultimately results in death. There are multi-domain frailty prevention programs: cognitive stimulation through games [13,14], the reduction of falls at home by the effectiveness of technology combined with a monitoring assistance center [15,16], management and optimization of medications using a connected device for dispensing medication [17] and the WHO program with the launch of the digital application, Integrated Care for Older People whose aim is healthy aging and the prevention of loss of autonomy [18]. Many of these programs evaluated as effective are in the developmental stages, and further research is needed to assess the cost-effectiveness and financial implications. The aim was to perform a systematic review of economic assessment of intervention strategies in the prevention of frailty in elderly of 60 years and over living at home.

We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline for reporting : The PRISMA 2020 statement : an updated guideline for reporting systematic reviews [19], adapted to the systematic review of the literature on economic assessments and structured around three main steps.

Step 1: Patients/Population, Intervention, Comparaison and Outcome (PICO) [20]

We identified the population of interest as the elderly of 60 years and over living at home. Interventional strategies for the intervention group can be interdisciplinary in the prevention of frailty, by a personalized care plan or by adapted digital tools or mixed, compared to usual care for the comparator group. The different global geriatric assessments were used followed by comprehensive economic assessments.

Research strategies

We have used all the terms associated with the PICO elements. The research strategy was developed from a team composed of 2 colleagues with expertise in the research area of this systematic review, e-health, health and autonomy, 3 colleagues with expertise in conducting systematic reviews (methodology) and 1 colleague whit expertise in health economics and medicoeconomic assessment. The keywords were: « frailty » AND « qaly » OR « cost-effectiveness analysis » OR « cost-utility analysis » OR « personalized care plan » OR « e-health » OR « elderly » OR « community-dwelling » OR « intervention ». The research strategy was carried out from 31/10/2010 to 31/12/2021 on the databases: PubMed, ScienceDirect, Google Scholar and Embase. The 2010 lower bound was chosen in consultation with the authors based on research already conducted by our research laboratory. In 2012 and 2013, Professor Achille Tchalla conducted similar research on the effectiveness of technologies on the prevention of falls in the homes of frail older people, and older people with and moderate Alzheimer’s disease [15,16]. We manually searched the references of all identified systematic reviews, as well as the included studies to identify other potentially relevant articles.

nclusion criteria

The studies included should meet the following criteria: elderly of 60 years and over living at home, prevention of frailty, identification of an interventional strategy to optimise the use of adapted digital tools (remote measurement or transmission of parameters, organizational solution for data analysis for remote medical monitoring of the elderly as well as the organization and management of alerts and interactive system for personalized interactions between health professionals and the elderly), or support through a personalized or mixed care plan and complete economic assessments. Cost-effectiveness assessment methods for estimating efficiency, as well as analyses for estimating a cost differential and a health outcome differential between several compared interventions were included. Original articles published in French and English (the languages spoken and understood by the authors), and mainly randomized controlled trials (RCT), quasi-experimental studies, cohort studies and decision analytic models were included. These studies were chosen to avoid bias, based on their levels of scientific proof in the literature. A grade A recommendation was based on scientific proof established by studies with a high level of proof. In contrast, a grade B recommendation was based on a scientific presumption provided by studies of intermediate level of proof. Only grade C recommendation studies based on lower level of proof studies were excluded [21].

Non-inclusion criteria

Elderly under of 60 years and not living at home (accommodation establishments for the dependent elderly are nursing homes and these residents need help and care everyday) were excluded. Studies without clear and precise interventional strategies were excluded. Lack of complete economic assessments, economic assessments based on grade C recommendation studies and economic assessments based exclusively on cost studies without comparison were excluded. The use of adapted digital tools in health that were not in the domain of frailty prevention was excluded.

Selection of studies

The first phase was to identify the articles to be included for a complete review. First, one of the authors (KG) removed all duplicates from the list. Then, five authors analyzed the titles and abstracts (CG, MLL, MLG, MDC and AT). Finally, each author indicated if an article should be included or excluded using the criteria defined above. In case of discrepancies, the authors worked together to reach a consensus on the list of articles. The second phase allowed the authors to read the articles in their entirety and independently to validate their inclusion. If, after complete reading, the article met any of the non-inclusion criteria, it was immediately excluded and deleted, and then the reason for this exclusion was noted. If it happened that several articles covered the same intervention, we selected the most relevant according to the study objectives, inclusion and non-inclusion criteria, and was generally the most recent. For systematic reviews and included articles, we manually went through the reference list.

Step 2: Assessment of the quality of the studies according to the recommendations: Consolidated Health Economic Evaluation Reporting Standards (CHEERS) Statement

The CHEERS reading grid was used to assess the quality of the studies in terms of economic assessments [22]. This grid is composed of 24 items and identifies four levels of quality, excellent quality level (score of 100%), good quality level (score from 76% to 99%), moderate quality level (score from 51% to 75%) and low-quality level (score ≤ 50%). Three authors (GK, MLG and AT) independently assessed each article. Disagreements on score levels were discussed and validated. Study quality scores were calculated for all published economic assessments according to the CHEERS statement. Studies of low methodological quality were excluded. The distribution of study quality assessments was presented in Table 1.

Step 3: Synthesis of the extraction of the results of the selected studies

Data extraction: One of the authors (KG) proposed to all authors (MLG, CG, MLL, MDC and AT) a list of categories containing variables extracted from the studies. For overall study characteristics, we extracted: first author, country, year of publication, country, study design, intervention group and comparator sample sizes, intervention group and the comparator descriptions, outcomes and measures. For the complete economic assessments data, we extracted: time horizon, perspective, cost assessment, incremental costeffectiveness ratios (ICER), economic methods, economic results and sensitivity analysis.

Quality control: The three steps described above have been independently double-checked by KG and MLG.

Definitions of cost-effectiveness analysis (CEA) and costutility analysis (CUA) [23]: CEA is a form of medico-economic assessment in which the consequences of strategies are assessed using a natural indicator expressed in physical units. This may be, for example, a number of years of life gained, a validated clinical outcome criteria that is closest to the benefit for the patient. In contrast, CUA is a form of medico-economic assessment in which the consequences of strategies are evaluated on the duration and quality of life. The most commonly used unit of measurement for this is the Quality-Adjusted Life-Years (QALY).

Figure 1 Figure A: Flow diagram for screening and selection processes, PRISMA 2020 (19).

No study met all 24 items of the CHEERS. Of the eleven studies included in our review [Figure 1], six studies (55%) were considered to be of good quality [24–29] and five studies (45%) considered to be of moderate quality [30–34] [Table 1].

Table 1: Study quality scores according to the CHEERS statement.

Overall characteristics of the studies

Of the eleven studies, nine studies were RCT and two quasi-experimental studies. Most studies were conducted in Europe, including three in the United Kingdom, one in Finland, five in the Netherlands and one in Spain. Only one study was conducted in Australia. Sample sizes ranged from a minimum of 191 participants to a maximum of 12,483 participants. Of these studies, seven mentioned having no conflict of interest, and four did not mention any. For four studies, their funding sources were public funding (public enterprises), three studies had publicprivate funding and one study was funded by the European Union. In contrast, three studies did not mention their funding. According to the publication dates of the studies, one study was published in 2020, three published in 2019, one published in 2018, two published in 2010, two published in 2015 and two published in 2010. The interventional strategies identified in each of the studies allowed us to classify them into three programs. Frailty screening included seven studies [24,27–29,31,32,34]. Frailty screening predicted the risk of loss of autonomy, falls, institutionalization, death and hospitalization of elderly of 60 years and over, within 1 to 3 years. The prevention of falls included three studies [25,30,33]. Accidental fall is defined as falling to the ground unexpectedly uncontrolled by will. Many extrinsic, behavioural or environmental factors are involved in the genesis of a fall and its possible traumatic consequences. Standard fall prevention measures must always be personalized, considering the dangers of the environment, the behaviour and the reaction capabilities of the person concerned. The analysis of drugs and treatments prescribed and dispensed included a study [26]. Prescription analysis is a structured and continuous expertise of the patient’s therapeutics, their modalities of use and the patient’s knowledge and practices. Its objective was to obtain an optimization of the efficacy and safety of therapeutics, as well as a costs minimization and optimal pharmacoadherence. All three programs were carried out with multidimensional and interdisciplinary approaches. The multidimensional approach aimed to assess all the physical, affective and social functions as well as the environment of the elderly. On the other hand, the interdisciplinary approach took advantage of the specific skills of the various health professionals, physiotherapists, occupational therapists, nurses (at home, in the general practitioner’s office and with geriatric expertise), social workers, general practitioners (GPs), geriatricians and pharmacists, implying close and coordinated collaboration with the aim of achieving the common objectives co-established with the elderly and her entourage. The overall characteristics of included studies are in Table 2.

Table 2: Overall characteristics of included studies.

Economic assessments

The methodological choices of complete economic assessments have made it possible to compare the differentials in costs and health outcomes of one or more health intervention strategies. CEA was implemented in four studies [26,30,33,34]. CUA was implemented in three studies [25,28,31]. CEAs and CUAs were implemented in four studies [24,27,29,32]. Regarding the perspective of the assessment, it was mostly restricted to institutions in charge of funding the health system for five studies. The time horizon of the assessment implemented was approximately one year for eight studies, nine months for one study, 24 months for one study and 5 years for another study. For one study, the costs and health outcomes have been discounted (≥ 12 months). The cost-effectiveness plans of these three programs described above classified the studies as dominant strategies or dominated strategies. Four studies had no conclusion on economic results: screening for frailty in elderly women at increased risk of frailty fractures [31], analysis of drugs and treatments prescribed and dispensed [26], fall prevention with balance and strength training for vulnerable elderly with Parkinson’s disease [25], and fall prevention in vulnerable elderly at high risk of falling [30]. Three studies had a dominant strategy, less expensive and more effective: screening for frailty among elderly at risk of frailty using the routine electronic medical record [32] and fall prevention through balance and strength training physical exercises among vulnerable elderly [33] and multi-domain management of frailty [28]. Four studies had a dominated strategy, more expensive and not effective: screening for frailty in elderly with progressively declining functional capacity who are at risk of being institutionalized within two years [34], screening and follow-up for frail elderly [24], multi-domain frailty screening to treat geriatric problems (in the somatic, psychological, functional and social domains) [27] and frail, poly-pathological elderly with a loss of autonomy [29]. The economics results are in Table 3.

Table 3: Economic assessments characteristics.

Retained effectiveness criteria

Health outcomes were assessed on the basis of different specific criteria presented in Table 3. In CEA, the different criteria identified in the studies were the following, physical competences, used nine times, Groningen Activity Restriction Scale (GARS) [35], Falls Efficacy Scale-International (FES-I) [36], Short Physical Performance Battery (SPPB) [37], Groningen Frailty Indicator (GFI) [38], modified version of the Falls Risk Assessment (FRA) Tool [39], Functional Independence Measure (FIM TM) [40], modified Katz-Activities of Daily Living (ADL) index score [41], Spanish version Appraisal of Self-care Agency Scale-Revised (ASA-R) [42], Drug-Related Problems (DRPs) [43] and physical, psychological and social competences, used twice Tilburg Frailty Indicator (TFI) [44,45]. In CUA, health outcome criteria used was the QALY, which weights the length of life by the quality of life. Healthy-related quality of life was measured by a utility score, reflecting preferences for different health states. The EQ-5D measurement system was mainly used in the studies.

In this systematic review of the literature, we included eleven studies. The objective of this review was to identify effective interventional strategies for the prevention of frailty in elderly of 60 years and over living at home. By grouping the interventional strategies from these studies, we identified three frailty prevention programs. These were the programs frailty screening, falls prevention and analysis of drugs and treatments prescribed and delivered. Several research works have been the subject of economic assessments in terms of cost-effectiveness on geriatric syndromes such as frailty and falls. In the aging population, falls are frequent, thus a significant frailty or vulnerability. At least one-third of elderly over 65 fall at least once a year. As a geriatric syndrome, like frailty, falls can be intrinsically and extrinsically multifactorial [15,46,47]. Elderly who have fallen have an impact on their quality of life, leading to increased morbidity, health care utilization, with direct consequences on the quite significant increase of health care costs [48–50]. The identification of precipitating factors and the performance of complete geriatric assessments, by an interdisciplinary team with geriatric expertise, have made it possible to detect at an early stage geriatric syndrome, then treated them. The combined cost-effectiveness and cost-utility analysis with retained effectiveness criteria were carried out from an institutional and societal perspective, which implies that all costs and outcomes were considered as far as possible. We find similar results in the literature of less expensive and more effective strategies [28,32,33,51]. Thus, frailty would be both a state of weakness and a reversible process of frailization on which it would be possible to act in a preventive perspective. It is presented as a state of unstable equilibrium between two bounds qualified in a variable way [8]. The choice to include frail elderly, or those at increased risk of functional decline, or having required formal and regular home help or home care or informal home assistance from the outset of a study would already be a major risk factor for frequent decompensation in poly-pathological cascades. The reversibility of the change in phenotypic profile from frail to pre-frail or even robust would require significant medical, paramedical and rehabilitation resources as well as requests to hospital services for their care without any guarantee of recuperation. Evidence of cost-effectiveness is limited [29,34,52,53]. Several reasons may explain this limitation: it is possible that the 12-month follow-up was too short to see preventive effects appear and the modified versions of some efficacy outcomes and QALYs measurements would not be sensitive enough to detect clinically relevant change. Polypharmacy is defined as the presence of 5 or more drugs, with an increased risk of adverse effects, hospitalization and cognitive impairment. Several studies have documented that taking 4 or more drugs was positively correlated with the occurrence of adverse drug events [17]. The regular analysis of the prescription has a positive impact on daily life and would improve the quality of life of frail and poly-pathological elderly [54]. The strengths of the studies included in this review were: an appreciation and acceptability of the study by the elderly, effectiveness of the interventional strategies demonstrated with savings made in terms of costs, reduction in the number of falls, reduction direct medical costs, reduction direct non-medical costs and improving the quality of life of elderly. The weak points of the studies were: lack of characterization of heterogeneity and uncertainty, lack of description of all the methods of statistical analysis (management of missing data, grouping of data, extrapolation of data), weakness of discussion, lack of information on the type of study funding and conflict of interest for some studies. No studies on adapted digital tools were included in the review over the chosen inclusion period, due to the lack of complete economic assessments. There are no perfect studies. Only three studies had less expensive and more effective multidimensional and interdisciplinary intervention strategies. They improved the quality of life of vulnerable elderly. This systematic review of the literature, carried out in four databases and over a period of 11 years, had the objective to identify effective interventional strategies, combined with an economic assessment, in the prevention of frailty in elderly of 60 years and over living at home. The economic results were more mixed for some studies. Many methodological weaknesses were present in these studies. The limitations of this systematic review are: included only two languages (English and French) and four databases (PubMed, ScienceDirecte, Google Scholar and Embase), did not include two other costs (cost minimization analysis and cost benefit analysis), inclusion period too short and possible selection and over-interpretation bias. Regarding implications and future research, we are currently conducting in France a first quasi-experimental study of the medico-economic assessment of a frailty prevention tool, using new technologies (digital tablet, domotics…). The main objective would be to evaluate the impact of the tool on the quality of life people aged 60 and over living at home.

We would like to thank all those who contributed to this study, from far and near.

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