Geriatric Patients with Hip Fracture: Frailty and Other Risk Factors Affecting the Outcome.

BACKGROUND: Hip fracture is a devastating health-care problem in a geriatric patient, leading to high mortality and morbidity. Preoperative risk assessment in the geriatric patient is often inexact because of the difficulty in measuring their poor physiologic reserves. AIMS: The primary objective was to find the association of modified frailty index (MFI) with 90-day mortality in geriatric patients who received anesthesia for fractured hip. Secondary objectives were to assess the association of preoperative waiting time with the 90-day mortality and the correlation of preexisting medical conditions with poor functional outcome among the survivors. SETTINGS AND DESIGNS: This prospective, observational study was conducted at a tertiary care institution. SUBJECTS AND METHODS: In this prospective observational study, done over a period of 1 year, 60 geriatric patients aged ≥65 years who received anesthesia for fractured hip and fulfilled selection criteria were recruited. The association of MFI with 90-day mortality and the correlation of preexisting comorbidities with poor functional outcome among the survivors were assessed. STATISTICAL ANALYSIS USED: Independent sample t-test, Mann-Whitney test, and odds ratio were used as applicable.
RESULTS: Total 60 patients were available for analysis as two patients dropped off from final 62 on follow up, fifty three patients survived after 90 days. MFI and 90-day mortality showed a significant direct correlation with P < 0.0001. However, no association was found between the preoperative waiting time and 90-day mortality. Preexisting medical conditions showed a significant association of dementia with total dependence afterward with a P = 0.02.
CONCLUSION: There is significant statistical correlation of MFI with the 90-day mortality in the geriatric hip-fractured patients undergoing surgery.

INTRODUCTION

With increasing geriatric patient population worldwide, hip fracture exists as a major health-care issue with its high mortality, morbidity, and financial liability. Anesthetists play a very important role in the perioperative care of these patients. Proximal femoral fractures carry distinctive challenges for the anesthetists as geriatric patients might harbor significant comorbidities.[1]

Although individual organ evaluation cannot be ignored in the geriatric patient, recognition of preoperative markers depicting the unique vulnerability of the geriatric patient (e.g., frailty, disability, and comorbidity) may provide additional insight in predicting perioperative complications and poor outcomes,[2] thus aiding preoperative decision-making. Frailty index may estimate physiologic reserves although its use is not fully evaluated in Indians with fractured hip.

Aims of the study

The primary objective was to find the association of modified frailty index (MFI), one of the frailty assessment tools, with 90-day mortality in the geriatric patients who received anesthesia for fractured hip. Secondary objectives were to assess the association of preoperative waiting time with the 90-day mortality and the correlation of preexisting medical conditions with poor functional outcome among the survivors.

SUBJECTS AND METHODS

This prospective, observational study was conducted after obtaining the Institutional Ethical Committee Clearance and patients' or legal guardian's consent. Patients aged 65 years or more with isolated hip fracture who could undergo the recommended hip surgery and complete the recommended treatment were included in the study. Those with diagnosed end-stage malignancy with metastasis, multiple fractures, road traffic accidents causing polytrauma, those opting for alternative therapies, or those were unable to be contacted for 90-day outcome evaluation were excluded from the study.

Those meeting the inclusion criteria were considered in our study and were observed prospectively, and the data were collected. Seventy-eight patients underwent surgeries related to hip fracture during a period of 1 year from January 1, 2016, to December 31, 2016.

Once diagnosed with hip fracture, after optimization of the medical conditions by different specialties, the patient was scheduled for surgery and considered for the study. On the day before the surgery, all study patients were contacted in person in the ward. Details regarding the conduct of the study and anesthetic details were discussed with the patient and the family. The necessary information such as preoperative, intraoperative, and postoperative data collection, ethical concerns, and privacy protection was explained to the patient and the caregiver. Informed consent was obtained following which the necessary data were recorded.

Data recorded preoperatively included demography of the patient, comorbidities, mode of injury, type of fracture, number of days after fracture for admission, preoperative consultations, name, relationship, and phone number of the caregiver, detailed preanesthesia evaluation, MFI, and waiting time (time from sustaining the fracture to surgery).

MFI was based on 19 of the potential 70 clinical deficits of the Canadian Study of Health and Aging (CSHA), which was validated by a previous study [Appendix 1].[34] The clinical deficits were obtained from the patient, from the caregiver, and also from the medical records, to calculate MFI.

MFI calculator

Click here for additional data file.

Each deficit, except mobility status, was dichotomized. “Zero” was assigned for the absence of a deficit and “one” for its presence. Mobility status was classified into three. Patients who were ambulatory without assistive devices were assigned “zero,” those who were ambulatory with walker or cane were assigned “one,” and nonambulatory or wheelchair/scooter-dependent patients were assigned “two.” There were thus a total of 19 clinical deficits with the potential for a maximum and minimum MFI of 20 and 0, respectively.[3] 90-day follow-up by phone call and assessment about activities of daily living (ADL) were made by the investigator if discharged.

The primary aim was to assess the association of MFI with 90-day mortality in patients aged 65 years or more who received anesthesia for hip fracture surgeries. Secondary objectives included the assessment of the correlation of the waiting time for surgery after sustaining the hip fracture and the 90-day mortality and also the influence of pre-existing medical condition on poor functional outcome of the survivors in the study population.

Minimum sample size was estimated as 55 patients based on the results of association of MFI on mortality in hip fracture patients in an earlier publication,[3] with 95% confidence, 80% power, and ratio of 1:10 for nonsurvivors to survivors. The ratio of 1:10 for nonsurvivors to survivors was taken based on assumed 30-day mortality rate of 8%–10% from reports of the National Institute for Health and Care Excellence.[5]

Data were compiled using MS Excel 2016 and analyzed using statistical SPSS 20.0 version (IBM Corp. Released 2011. IBM SPSS Statistics for Windows, Version 20.0. Armonk, NY: IBM Corp). Quantitative variables were expressed as descriptive statistics such as mean, standard deviation, and proportion. Independent samples t-test was used to find out the comparison of the mean of MFI. The influence of waiting time on the 90-day mortality was analyzed using Mann–Whitney test. Association between the preexisting comorbidities and functional outcome was calculated using odds ratio. P < 0.05 was considered statistically significant.

RESULTS

Seventy-eight patients were assessed for eligibility. Twelve among them were under the age of 65 years, four had terminal malignancies diagnosed before sustaining the fracture, and two patients could not be contacted. Sixty patients met the criteria for final analysis. Fifty-three patients were alive at the end of 90 days after surgery, and seven died at various points of time during this period. Two patients died in the first 1 week after surgery in the hospital itself, and five patients died after discharge, out of which two died in the 1st month and three within the following 2 months.

In this study population, there were 34 (56.7%) males and 26 (43.3%) females. The majority of the patients belonged to a higher American Society of Anesthesiology (ASA) Physical Status. Status. Number of patients belonging to ASA class I, II, III and IV were 0, 11, 35 and 14 respectively. Majority of patients (n = 42, 70%) received combined spinal–epidural anesthesia and nine patients (15%) received general anesthesia. Number of patients who received subarachnoid block and general anesthesia with epidural analgesia were 5 and 4, respectively.

Among the 60 patients analyzed, majority of the study population had MFI scores of 2–4 (20%, 16.7%, and 23.3%, respectively) [Figure 1]. Mean calculated MFI score was 3. When categorized as two groups, those with scores ≤3 and those >3 showed equal distribution [Table 1 and Figure 2]. All patients with MFI ≤3 were alive at 90 days after surgery while the mortality was 23.3% among those who had MFI >3. This association was statistically significant, with P < 0.0001.

Figure 1

Distribution of modified frailty index

Table 1

Association of modified frailty index with 90-day mortality

Figure 2

Association of MFI with 90 day mortality

When analyzing, we found that the median waiting time in the survived group was 6 days (1–60 days) and in the nonsurviving group was 9 days (4–12 days). Comparing these two sets of patients, it was found that there was no association of waiting time with 90-day mortality (P = 0.172) [Table 2].

Table 2

Association of waiting time in days with 90-day mortality

Of the 53 surviving patients, 39 patients were independent and able to return back to their previous function. However, five patients required assistance for ADL and nine patients were fully dependent and bedbound. On analyzing preexisting medical illness and functional outcome, those who had poor functional outcome (bedbound) had significant relationship with preexisting dementia with a P = 0.02 and odds ratio of 17.1 (2.9–99.4) [Table 3].

Table 3

Association of comorbidity and poor functional outcome

DISCUSSION

Hip fractures occur more commonly in the geriatric population. They are likely to develop several adverse events, decrement of functional ability, institutionalization, and mortality after surgery more frequently than their younger counterparts because of their distinctive physiologic vulnerability.[5]

Frailty is defined as a process of progressive multisystem decline which leads onto diminished physiological reserve and poor capacity to respond to physiological stress.[4] Frailty with its high prognostic value renders significance in the primary care practice as it can be incorporated as a diagnostic tool for many clinical decisions and discussions.[6] However, there are limited data in quantifying frailty and its association with postoperative complications, which may contribute to the high morbidity and mortality observed in the Indian population.

This study was done prospectively on a homogenous group of geriatric patients receiving anesthesia for hip fracture surgery from a single tertiary care center. Male predominance was observed in this small group unlike several other studies as that of Tanner et al.,[7] where female predominance was reported for proximal hip fracture.

Strong association was found in our study between the MFI and the 90-day mortality after proximal femoral fractures, suggesting its potential use in prognostication and predicting the mortality. Patients with an MFI of ≥3 had significantly higher association for mortality (P < 0.001). Our results support the association of mortality and frailty demonstrated by other studies in multiple settings.[348910]

Frailty is not merely an expression of aging; it depicts a multidimensional syndrome with physiological changes accumulated over the years on a person. Canadian Society of Health and Aging (CSHA) frailty scale, one of the many different tools to measure frailty is popular among geriatricians.[4] MFI we used is a validated scoring tool used by Patel et al. in the hip fracture patients; the deficits are derived from the CSHA Clinical Fraility Scale.[3] Nottingham Hip Fracture Score is another well-validated scoring tool by Wiles et al. in hip fracture patients in the UK,[8] which has mini-mental status and institutional living as its components, was found to be not practically feasible in our set of patients.

Chance for quality treatment in Indian population in average settings gets hindered by factors such as distance from home, poor management of ailments, associated comorbidities, and ensuing complications. This in turn deprives them off the best and timely treatment that can be offered, again emphasizing the impact of an early presentation and operative management on prognosis and functional outcomes in hip fractures.

In this study population, no statistically significant difference was found (P = 0.172) in the waiting time to surgery between the survivors and nonsurvivors on the mortality rate. Some other studies have also made similar observations, showing lack of significant effect of waiting period on postoperative morbidity and mortality.[1112] However, delaying surgery beyond 48 h from admission is reported to be associated with prolonged hospital stay, increased morbidity (pressure sores, pneumonia, thromboembolic complications), and increased mortality on prolonged delay.[13] It is recommended to triage these patients to fast-tracking pathway to have an accelerated optimization to allow early surgery.[131415] Early surgery is the best mode of analgesia.

Majority (73.6%) of the patients in this study got back to independent function after 90 days of surgery. We observed that nine patients continued to be fully dependent and bedridden at home even after 90 days postoperatively. Preexisting medical conditions in our study population found significant association of dementia with total dependence (odds ratio [95% CI]: 17.1 [2.9–99.4]) [Table 3]. Elsewhere, neurological and kidney-related diseases were found to have the highest impact on functional outcomes and mortality rates.[1617]

This was the observation made over a period of 1 year from a single center where mostly middle-class or lower-middle-class population is catered. Most of these patients had spent valuable initial days after fall either at home or at local primary care before approaching our center for surgery. The observed 1-month mortality is 6.7% (4/60) in this small sample which is much lower than other reports. In this region, either a family member or a hired caregiver nursed the patient all the time which may not be the scenario everywhere in this country or rest of the world of published literature. Two patients who died while in the hospital had postoperative complication Grade IV on Clavien–Dindo classification. One of them was a nonagenarian with cardio-renal syndrome needing dialysis, and the other had advanced scleroderma with right heart failure (MFI 8 and 5, respectively). The other two patients who died after discharge had MFI 11 and 8 and had developed gastrointestinal bleed later complicated by anticoagulation and dual antiplatelet drugs.

Recommendations are available for the implementation of multidisciplinary hip fracture management group including orthogeriatrician and standard care pattern or pathway for this special group of vulnerable patients.[518192021] Standardization has shown to reduce care variability and improve patient outcome, including the management of hip fractures.[22] An introduction of national standards in anesthesia care for hip fracture in India can coherently be expected to have similar benefits. ASA score alone cannot predict the postoperative outcome in elderly frail patients.[2123] There is a need to develop and improve available tools for frailty screening in the preoperative assessment.

CONCLUSION

MFI and 90-day mortality of geriatric patients undergoing anesthesia for fractured hip surgeries are significantly correlated. Preoperative evaluation should include frailty assessment for prognostication and in tailoring the individual patient care plans for improved outcomes.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.