Associations of frailty with health care costs – results of the ESTHER cohort study

Bock et al. BMC Health Services Research (2016) 16:128 DOI 10.1186/s12913-016-1360-3 RESEARCH ARTICLE Open Access Associations of frailty with health care costs – results of the ESTHER cohort study Jens-Oliver Bock1*, Hans-Helmut König1, Hermann Brenner2,3, Walter E. Haefeli4, Renate Quinzler4, Herbert Matschinger1,5, Kai-Uwe Saum2, Ben Schöttker2 and Dirk Heider1 Abstract Background: The concept of frailty is rapidly gaining attention as an independent syndrome with high prevalence in older adults. Thereby, frailty is often related to certain adverse outcomes like mortality or disability. Another adverse outcome discussed is increased health care utilization. However, only few studies examined the impact of frailty on health care utilization and corresponding costs. The aim of this study was therefore to investigate comprehensively the relationship between frailty, health care utilization and costs. Methods: Cross sectional data from 2598 older participants (57–84 years) recruited in the Saarland, Germany, between 2008 and 2010 was used. Participants passed geriatric assessments that included Fried’s five frailty criteria: weakness, slowness, exhaustion, unintentional weight loss, and physical inactivity. Health care utilization was recorded in the sectors of inpatient treatment, outpatient treatment, pharmaceuticals, and nursing care. Results: Prevalence of frailty (≥3 symptoms) was 8.0 %. Mean total 3-month costs of frail participants were €3659 (4 or 5 symptoms) and €1616 (3 symptoms) as compared to €642 of nonfrail participants (no symptom). Controlling for comorbidity and general socio-demographic characteristics in multiple regression models, the difference in total costs between frail and non-frail participants still amounted to €1917; p < .05 (4 or 5 symptoms) and €680; p < .05 (3 symptoms). Among the 5 symptoms of frailty, weight loss and exhaustion were significantly associated with total costs after controlling for comorbidity. Conclusions: The study provides evidence that frailty is associated with increased health care costs. The analyses furthermore indicate that frailty is an important factor for health care costs independent from pure age and comorbidity. Costs were rather attributable to frailty (and comorbidity) than to age. This stresses that the overlapping concepts of multimorbidity and frailty are both necessary to explain health care use and corresponding costs among older adults. Keywords: Economic, Utilization of services, Frailty, Costs, Old age Background Life expectancy increases substantially in virtually all developed countries [1], leading to a larger number of older people living in these countries. Old age is accompanied by many geriatric phenomena that include, for example, multiple chronic conditions, also referred to as ‘multimorbidity’ [2, 3]. As the number of people in old age increases, many studies investigated the impact of multimorbidity on health care costs [4]. These studies find in general a positive association of multimorbidity and health care * Correspondence: 1 Department of Health Economics and Health Services Research, Hamburg Center for Health Economics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, Hamburg 20246, Germany Full list of author information is available at the end of the article costs, stressing the importance of this phenomenon for the health care system. Another medical phenomenon associated with age is people’s vulnerability to negative health outcomes and the general loss of resources. This phenomenon of frailty has increasingly received attention during the past decades. Thus, it has been shown that frailty is frequent in old age [5], and the number of frail people is expected to rise rapidly due to demographic change, stressing its importance for health care systems. Despite the great attention in the gerontological field, there is no generally accepted definition of frailty [6–8]. © 2016 Bock et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Bock et al. BMC Health Services Research (2016) 16:128 Fried et al. proposed a definition of frailty that characterizes it as an independent phenotype differing from comorbidity and disability [9]. According to their definition, frailty is a clinical syndrome constituted by the cooccurrence of at least three of the following five criteria: unintentional weight loss, exhaustion, weakness, slow walking speed, and low physical activity. Fried et al. [9] as well as other studies [10] related frailty to certain ‘adverse outcomes’, for which the predictive validity of frailty has been investigated. For example, frailty has been found to be highly predictive for mortality [11–14]. Another adverse outcome potentially associated with frailty is increased health care utilization. Some studies examined the relationship between frailty and health care utilization, finding in particular an increased hospitalization rate among frail older adults [9, 15–21]. In order to extend these studies and provide evidence from a representative large population-based sample, we aimed at examining comprehensively the effect of frailty on health care utilization and corresponding costs in all important health care sectors, including inpatient services, outpatient services, pharmaceuticals, and nursing care. Thus, it was our goal to present cost estimates for frailty. In particular, the aims of this study were i) to investigate the relationship between frailty and health care costs in a large sample of older adults and ii) to determine the respective associations of the different frailty criteria and health care costs. Methods Sample The cross-sectional analyses presented in this manuscript are based on the 8-year follow-up wave of the “Epidemiological investigations on chances of preventing, recognizing early and optimally treating chronic diseases in an elderly population”, the ESTHER-Study. ESTHER is a large prospective observational cohort study of older Germans. For this study, 9949 patients, aged 50–75 years, were recruited via their GPs in the Saarland, Germany between July 2000 and December 2002. Participants’ socio-demographic and lifestyle factors were collected by standardized questionnaires and clinical data by their general practitioners (GPs) and study physicians. Follow-up questionnaires were sent to the participants and their GPs 2, 5 and 8 years after recruitment. From baseline-recruitment to the 8-year foll (...truncated)