Frailty is a critical issue in modern medical practice due to its association with adverse health events, poor patient outcomes and an increased burden on our healthcare system. Frailty is most commonly found in the elderly, and this population is increasing disproportionately worldwide. In New Zealand it is expected to double from 700,000 in 2016 to around 1.4 million by 2040.1 In 2012 in the US, despite only accounting for 12% of the total population, elderly patients accounted for 35% of all hospital admissions.2 This cohort also had a significantly longer average hospital stay and an increased average cost per stay.2
Frailty can be thought of as a state of increased vulnerability across multiple organ systems, resulting in poor physiologic reserve, and thus inability to respond to stressors.3 This concept is increasingly recognised as a separate entity from ageing and comorbidity;4 and when appropriately measured is an independent risk factor for adverse patient outcomes.3,5 Multiple large prospective cohort studies have shown frailty is associated with an increased risk of worsening disability, hospitalisation, discharge to a care facility, morbidity and mortality.6,7 Fried et al in the Cardiovascular Health Study showed severe frailty was associated with a significantly increased risk of falls (HR =1.23), worsening disability (HR =1.79), hospitalisation (HR =1.27) and death (HR =1.63) over seven years.7
Frailty is a dynamic process; however, without intervention frailty appears to be a progressive process with progression to greater degrees of frailty over time.8 The development of frailty often leads to a spiral of decline with increasing frailty, worsening disability, multiple hospital admissions and subsequent death.5 Multiple interventions to modify frailty have been examined, however, few have been shown to be associated with improved patient outcomes. Transitional care has the potential to attenuate or possibly reverse this process of frailty leading to improved patient outcomes, including a reduction in unplanned patient readmissions.
Readmission rate is one of the quality indicators of patient care utilised worldwide as it reflects both the impact of hospital care on a patient’s illness and the coordination of care in the transition period after index discharge. Unplanned readmissions are associated with poor patient outcomes such as mortality and are deemed preventable to a degree. As outlined above, readmission to hospital is often part of a precipitous decline in this population. The preventable nature of unplanned readmission makes this a potential target for improvement.
Heppenstall et al,9 in their cohort of elderly frail patients undergoing a transitional care intervention, show a high readmission rate of 42% at three months despite intervention. In addition, the majority of these readmissions were comprised of new acute medical or surgical problems and exacerbations of chronic medical conditions, thus highlighting the vulnerable nature of this frail population. Without a control group, it is unclear as to whether transitional care input has modified this readmission risk.
Nonetheless, this significant finding highlights two important considerations with regards to the use of readmission rate as a quality indicator of hospital care. Firstly, the ability to predict patients at high risk of unplanned readmission would facilitate the targeted use of individualised transition care interventions, and potentially improved patient outcomes if successful. The utility of current research in predictive model development is limited by significant heterogeneity in the literature.10 One of the sources of heterogeneity is the lack of standardisation in the definition of readmission itself. Readmission time intervals used in the literature range from two weeks to one year after discharge. This varying definition is a threat to the external validity to this quality indicator of inpatient care, and limits comparison between studies.11 Previous research has recommended the use of a 30-day time frame after index discharge as a satisfactory balance between capturing readmissions reflective of the index inpatient care and minimising unrelated readmissions, often due to underlying disease progression despite optimal care.12 In this study, it is difficult to delineate whether the readmissions from new acute medical problems were due to progression of longstanding illness or were related to circumstances of the index admission. They note a peak in readmissions at 30 days post-discharge. A comparison between 30-day readmissions and 90-day readmissions in the context of readmission diagnosis classification could clarify this further.
Secondly, the reasons for readmission in this cohort were in keeping with international research on readmissions in medical patients. While the proportion of surgical patients comprising the study sample is not specified, research has shown clear differences in readmission risk between medical and surgical patients. This is reflected by the lower readmission rates and reasons for unplanned readmission of the latter. Majority of unplanned surgical readmissions are due to postoperative complications rather than exacerbation of underlying comorbidity.13 This represents a fundamental difference between the two cohorts and should be considered further.
In conclusion, frailty is an important emerging concept in medical practice encompassing a group of vulnerable individuals with reduced physiological reserves who are at high risk of adverse clinical outcomes, including unplanned readmissions. This study by Heppenstall et al emphasises the ever-increasing impact of frailty on patients, their families and the healthcare system as shown by the high “unavoidable” readmission rate. Further research into methods to modify or attenuate frailty and into the aetiological factors of unplanned readmission in this cohort may help identify high-risk patients and allow targeted transitional care interventions.