Abstract
Purpose
The coronavirus disease 2019 (COVID-19) pandemic led to mandatory screening of hospitalized patients. This study aims to assess the impact of COVID-19 admission delays on clinical outcomes, specifically complications and mortality, in elderly patients following hip fracture surgery.
Materials and Methods
This study included 563 patients (aged ≥70 years) who underwent hip fracture surgery between February 2018 to January 2021 and were followed up for at least one year. The cohort was divided into two groups: a pre-COVID-19 pandemic group (control group) and a COVID-19 pandemic group (study group). The patients who tested positive for COVID-19 were excluded. The demographic data, the time from injury to surgery, admission to surgery, postoperative complications, and 1-year mortality were collected and compared between the two groups.
Results
The time from injury to surgery was significantly longer in the study group compared to the control group, primarily due to delays in the time from injury to hospital visit and from hospital visit to admission (4.6 days vs. 3.7 days, P=0.026). However, there was no significant difference between the groups from admission to operation. The incidence of postoperative medical complications and one-year mortality rate were significantly higher in the study group (P=0.025 and P=0.034).
Conclusion
Our findings suggest that delays in the time from injury to hospital visit and hospital visit to admission during the COVID-19 pandemic led to significant delays in hip fracture surgery for elderly patients. These delays were associated with increased postoperative medical complications and a higher one-year mortality rate.
Keywords: Elderly patients, Hip fracture, COVID-19 pandemic, Complication, Mortality
INTRODUCTION
Hip fractures are one of the common osteoporotic fractures with high morbidity and mortality1,2). One-year mortality following hip fracture surgery in the age group ranged from 27%-34%3,4). Several studies have reported the risk factors of mortality, including age, mental status, and medical comorbidities5-7). Additionally, surgical delays have also been identified as a significant risk factor for morbidity and mortality8-10). Therefore, underscoring the importance of early surgery in these patients minimizes morbidity and mortality11).
Since the first coronavirus disease 2019 (COVID-19) outbreak in early 2020, there have been significant disruptions to the healthcare systems12). Even amid the spread of COVID-19, patients requiring urgent treatment and surgery received care in tertiary hospitals. To ensure the normal functioning of tertiary hospitals, distinguishing and separating patients with COVID-19 from those without the infection was necessary. Therefore, COVID-19 screening measures were implemented to check for respiratory symptoms in hospitalized patients. There were delays in the time from hospital visits to admission until viral test results were confirmed.
These standard protocols inevitably delayed preoperative evaluation and time from injury to surgery for patients with hip fracture surgery. Despite these challenges, the incidence of hip fracture remained unaltered, but there was a significant impact on fracture care and surgical outcomes, especially among the elderly13,14). It was reported that hip fracture management during the COVID-19 pandemic in this age group was associated with higher morbidity and mortality15). However, the evidence is conflicting, and research analyzing the impact of the COVID-19 pandemic on hip fracture patient care remains lacking16). Only a few studies have compared surgical outcomes, including morbidity and 1-month and 1-year mortality rates, between pre-COVID-19 and COVID-19 pandemic groups in a large cohort.
This study aimed to assess the impact of the COVID-19 pandemic on clinical outcomes, including complications and mortality, after hip fracture surgery in elderly patients. We also seek to compare the outcomes with patients who underwent hip fracture surgery before the COVID-19 pandemic.
MATERIALS AND METHODS
This study was approved by the Institutional Review Board of Hallym University Sacred Heart Hospital (approval No. 2022-10-027). Due to its retrospective nature, the Institutional Review Board waived the requirement of informed consent. The study included elderly patients (age ≥70 years at the time of injury) who underwent hip fracture surgery between February 2018 and January 2021 at our hospital and were followed up for at least 1 year. In total, 570 patients were enrolled in this study. Among them, 292 patients underwent closed reduction and intramedullary nailing for pertrochanteric fractures, and 278 patients underwent cementless bipolar hemiarthroplasty for femoral neck fractures or unstable basicervical intertrochanteric fractures. The patients were divided into two groups: the control group (the patients treated before the COVID-19 pandemic from February 2018 to January 2020) and the study group (patients treated during the COVID-19 pandemic period from February 2020 to January 2021). Patients with confirmed COVID-19 infection were excluded from the study, as they were transferred to other hospitals due to our hospital policy. Additionally, patients diagnosed with COVID-19 infection during hospitalization or outpatient follow-up were excluded. Finally, the control group comprised 403 patients, while the study group included 160 patients (Fig. 1).
Fig. 1.
Flowchart demonstrating patient selection. THA: total hip arthroplasty, COVID-19: coronavirus disease 2019.
Since February 2020, strict COVID-19 screening protocols have been implemented to prevent the risk of infection spread. On visiting the emergency room, respiratory symptoms were first checked. If no symptoms were present, patients were placed in the main room of the emergency room. However, when respiratory symptoms were detected, the patient was moved into an isolation room. All emergency room treatment was initiated with the staff donning four types of protective equipment. X-ray imaging test was conducted in the emergency room’s exclusive X-ray room.
For patients diagnosed with hip fracture and requiring surgery, a real-time polymerase chain reaction test for COVID-19 infection was performed. The patient’s admission procedure could not proceed until the test result was obtained. Patients with positive test results were not hospitalized and were transferred to other hospitals dedicated to COVID-19 care. Only patients with negative COVID-19 test results proceeded with hospitalization, followed by preoperative evaluation and medical optimization.
Both groups underwent the same procedures after hospitalization. Mechanical thromboprophylaxis using an intermittent pneumatic compression device and graduated compression stockings was implemented in all patients and was continued until discharge. Patients underwent imaging studies, including three-dimensional (3D) CT, for a detailed assessment of the fracture pattern before surgery. Multidisciplinary consultations were performed for all patients to assess the surgical risk and optimize individual medical conditions.
All surgeries were performed by two experienced hip surgeons at a single center. Postoperatively, low-molecular-weight heparin was used as a prophylactic agent. Rehabilitation began 2 to 3 days postoperatively, with tolerable weight bearing and ambulation using a walker in accordance with institutional protocols. Routine follow-up visits were scheduled at 6 weeks and 3, 6, 9, and 12 months postoperatively, with annual follow-ups thereafter. Patients or their families were contacted via telephone if they missed scheduled visits.
The following data were collected from medical records: Demographic data, which included age, sex, body mass index, American Society of Anesthesiologists score, comorbidities, and bone mineral density. Preoperative parameters included the time from injury to operation, including the time from injury to hospital visit, time from hospital visit to admission, and time from admission to operation, and preoperative antiplatelet medication administered for comorbidities. We defined the admission as the patients presented in a general ward. During the COVID-19 pandemic, this admission meant the release from the mandatory quarantine and the initiation of preoperative evaluation and medical optimization because the patients could not move.
Perioperative data included operation time, anesthesia type, transfusion rate, length of intensive care unit (ICU) and hospital stays, and the incidence of ICU admission after surgery. Postoperative data included the rates of venous thromboembolism, delirium, readmission, and medical and surgical complications, and in-hospital, 1-month, and 1-year mortality rates.
Statistical analyses were conducted using IBM SPSS Statistics software (ver. 24.0; IBM Corp.). Independent t-tests were used to compare numerical data, expressed as mean±standard deviation. Chi-square and Fisher’s exact tests were used to compare categorical data. For all analyses, a P-value of <0.05 was considered statistically significant.
RESULTS
The time from injury to a hospital visit and the time from a hospital visit to admission were significantly delayed in the study group compared to the control group (2.8±4.9 days vs. 1.4±2.6 days, P=0.037; 416.2±224.4 minutes vs. 295.4±134.6 minutes, P=0.019). Subsequently, the time from injury to operation was also significantly longer in the study group than in the control group (4.6±6.1 days vs. 3.7±3.1 days, P=0.026). However, there was no significant difference between the groups from admission to surgery. Also, there were no significant intergroup differences in the demographic and the other preoperative data (Table 1). Also, no significant difference in comorbidities between the two groups was observed (Table 2).
Table 1.
Demographic and Preoperative Data in Both Groups
| Control group (n=403) | Study group (n=160) | P-value | |
|---|---|---|---|
| Age (yr) | 83.2±6.2 | 84.6±5.7 | 0.064 |
| Sex, male:female | 91:312 | 34:126 | 0.732 |
| Body mass index (kg/m2) | 21.8±3.8 | 21.6±4.0 | 0.550 |
| Bone mineral density (T-score, femur neck) | –3.1±1.0 | –3.2±1.0 | 0.414 |
| Time from injury to hospital visit (day) | 1.4±2.6 | 2.8±4.9 | 0.037* |
| Time from hospital visit to admission (min) | 295.4±134.6 | 416.2±224.4 | 0.019* |
| Time from admission to operation (day) | 3.0±2.6 | 3.1±2.9 | 0.485 |
| Time from injury to operation (day) | 3.7±3.1 | 4.6±6.1 | 0.026* |
| ASA score | 0.111 | ||
| II | 16 (4.0) | 5 (3.1) | |
| III | 313 (77.7) | 116 (72.5) | |
| IV | 74 (18.4) | 39 (24.4) | |
| Preoperative antiplatelet medication | 170 (42.2) | 54 (33.8) | 0.065 |
| Preoperative levels | |||
| Hb (g/dL) | 11.2±1.7 | 11.4±1.9 | 0.347 |
| Hct (%) | 33.4±4.9 | 33.6±5.5 | 0.715 |
Values are presented as mean±standard deviation, number only, or number (%).
ASA: American Society of Anesthesiologists, Hb: hemoglobin, Hct: hematocrit.
*P<0.05.
Table 2.
Comorbid Medical Diseases between the Two Groups
| Control group (n=403) | Study group (n=160) | P-value | |
|---|---|---|---|
| Cardiovascular | 330 (81.9) | 123 (76.9) | 0.177 |
| Pulmonary | 90 (22.3) | 27 (16.9) | 0.151 |
| Endocrinologic | 29 (7.2) | 16 (10.0) | 0.269 |
| Neurologic | 104 (25.8) | 42 (26.3) | 0.914 |
| Psychiatric | 95 (23.6) | 47 (29.4) | 0.153 |
| Nephrologic | 70 (17.4) | 25 (15.6) | 0.619 |
| Gastrointestinal | 19 (4.7) | 10 (6.3) | 0.458 |
| Rheumatoid | 17 (4.2) | 2 (1.3) | 0.079 |
Values are presented as number (%).
In terms of perioperative data, there were no significant differences between the two groups in the operation time, anesthesia method, perioperative transfusion rate, rate of ICU admission, and lengths of ICU and hospital stay (Table 3).
Table 3.
Comparison of Perioperative Data between the Two Groups
| Control group (n=403) | Study group (n=160) | P-value | |
|---|---|---|---|
| Operation time (min) | 72.4±25.2 | 74.9±28.9 | 0.312 |
| Anesthesia, general:spinal | 369:34 | 148:12 | 0.715 |
| Immediate postoperative Hb (g/dL) | 10.5±1.4 | 10.6±1.3 | 0.859 |
| Immediate postoperative Hct (%) | 31.6±4.0 | 31.3±3.7 | 0.396 |
| Transfusion rate | 268 (66.5) | 96 (60.0) | 0.146 |
| Intraoperative transfusion rate | 205 (50.9) | 77 (48.1) | 0.558 |
| Postoperative transfusion rate | 148 (36.7) | 46 (28.8) | 0.073 |
| Transfusion rate in Hb >8 g/dL | 19 (4.7) | 3 (1.9) | 0.117 |
| ICU admission | 112 (27.8) | 54 (33.8) | 0.163 |
| ICU stay (day) | 2.8±4.0 | 1.9±1.1 | 0.082 |
| Hospital stay (day) | 18.1±12.0 | 16.8±6.7 | 0.175 |
Values are presented as mean±standard deviation, number only, or number (%).
Hb: hemoglobin, Hct: hematocrit, ICU: intensive care unit.
In terms of postoperative complications and mortality, there were no significant intergroup differences in the incidences of deep vein thrombosis, pulmonary embolism, delirium, and readmission and in-hospital and 1-month mortality rates. However, the incidence of medical complications was higher in the study group than in the control group (51.9% vs. 41.4%, P=0.025) although there was no significant difference in the incidence of surgical complications (Table 4). One-year mortality rate was significantly higher in the study group than in the control group (27.5% vs. 19.4%, P=0.034).
Table 4.
Comparison of Postoperative Complications between the Two Groups
| Control group (n=403) | Study group (n=160) | P-value | |
|---|---|---|---|
| DVT | 7 (1.7) | 3 (1.9) | 0.414 |
| PE | 3 (0.7) | 2 (1.3) | 0.116 |
| Delirium | 144 (35.7) | 70 (43.8) | 0.077 |
| Readmission | 6 (1.5) | 2 (1.3) | 0.829 |
| Medical complications | 167 (41.4) | 83 (51.9) | 0.025* |
| Cardiovascular | 20 | 10 | |
| Pulmonary | 80 | 36 | |
| Cerebrovascular | 7 | 6 | |
| Nephrologic | 35 | 17 | |
| Urologic | 41 | 22 | |
| Gastrointestinal | 19 | 4 | |
| Surgical complications | 9 (2.2) | 3 (1.9) | 0.791 |
| Bipolar hemiarthroplasty | |||
| Dislocation | 3 | 1 | |
| Periprosthetic joint infection | 2 | 1 | |
| Cephalomedullary nailing | |||
| Wound infection | 4 | 1 | |
| In-hospital mortality | 12 (3.0) | 7 (4.4) | 0.409 |
| 1-Month mortality | 22 (5.5) | 9 (5.6) | 0.938 |
| 1-Year mortality | 78 (19.4) | 44 (27.5) | 0.034* |
Values are presented as number (%) or number only.
DVT: deep vein thrombosis, PE: pulmonary embolism.
*P<0.05.
DISCUSSION
During the COVID-19 pandemic, every aspect of social life and healthcare systems was affected. It prompted the governments to adopt a series of lockdown measures to limit the spread of the COVID-19 virus, including extensive testing, quarantine, and banning gatherings17). This pandemic posed significant challenges for tertiary hospitals, particularly regarding patient access, infectious complications, and the threat of iatrogenic transmission. Strict screening measures were implemented to prevent the transmission of infection within the hospital. All patients presenting at the emergency room were thoroughly checked for respiratory symptoms and quarantined accordingly. Physical examination and epidemiological investigations, such as movement line confirmation, were also carried out along with COVID-19 screening tests on all patients. Although the hospitalization process was delayed significantly, other medical processes were carried out as quickly as possible.
Delayed surgery in elderly patients with hip fractures is shown to increase morbidity and mortality8-10,18,19). Furthermore, the patients who undergo delayed surgery are exposed to inflammation and hypercoagulable states for a longer time than those whose surgery is not delayed20,21). For instance, Shen et al.22) stated that early surgery for hip fracture patients is of paramount importance because it can restore motor function and reduce bed rest-related complications.
The current study aims to determine whether the inevitable delay in hospitalization caused by the COVID-19 pandemic resulted in increased postoperative complications and mortality in hip fracture surgery patients. Only a few studies have published short-term follow-up results on surgical outcomes of patients who underwent hip fracture surgery during the COVID-19 pandemic. However, they were not large-cohort studies that compared the results with patients in the pre-pandemic period.
In the current study, there was a significant difference in the time from injury to surgery between the two groups. However, there was no significant difference in the time from admission to operation. This difference is attributed to the delayed time from injury to the completion of admission, as shown in our results. As a result, all patients remained in bed due to severe pain and were vulnerable to bed rest-related complications. A previous study by Vidal et al.23) revealed that the mortality after hip fracture surgery was related to the time delay from injury to hospital admission and the time from injury to surgery. Pincus et al.24), have also reported that an increased wait time was associated with a greater risk of 1-month mortality and other complications, with a wait time of 24 hours as the threshold defining higher risk. These findings suggest that early hospitalization and management of hip fractures can significantly reduce postoperative complications and mortality. Similarly in our results, the delay from injury to hospital visit and from hospital visit to admission caused increased postoperative medical complications and 1-year mortality.
Our study revealed that the incidence of postoperative medical complications and 1-year mortality rate were significantly higher in the COVID-19 pandemic group than in the pre-COVID-19 pandemic group. Similar findings were reported by Shen et al.22), who observed that elderly patients with hip fractures who underwent total hip arthroplasty during the COVID-19 pandemic had higher postoperative medical complications and a 3-month mortality rate. Elderly patients over 70 years enrolled in this study are particularly vulnerable to postoperative medical complications such as pneumonia, urinary tract infection, and acute kidney injury. These complications eventually delay rehabilitation, prolong hospital stays, and contribute to increased mortality.
In the current study, although the study group showed a higher incidence of medical complications, these were detected early and promptly treated by the medical team, which prevented an increase in hospital stay, and in-hospital and 1-month mortality rates. Importantly, patients diagnosed with COVID-19 during hospital stays or outpatient follow-up visits were excluded from the study to rule out the direct effect of COVID-19 on postoperative medical complications and mortality. Therefore, we believe the increased incidence of postoperative medical complications and mortality in the COVID-19 pandemic group can likely be attributed to the delays in surgery, which had long-term effects on patient outcomes and were a major contributing factor to the significantly higher 1-year mortality rate in this group.
However, this study had a few limitations. First, this was a retrospective study conducted at a single center despite the prospectively compiled data. Second, we could not predict how long it would take to receive COVID-19 test results for each patient, which may have introduced variability. Third, the incidence of thromboembolism could not be assessed accurately, as only patients with clinical symptoms were subjected to diagnostic tests such as ultrasonography or 3D CT-angiography. Finally, we could not include patients diagnosed with COVID-19 as they were transferred to hospitals dedicated to COVID-19 treatment.
Nevertheless, to the best of our knowledge, this is the first single-center study to assess the impact of the COVID-19 pandemic on surgical outcomes, including complications and in-hospital, 1-month, and 1-year mortality rates among elderly patients (≥70 years of age) who underwent hip fracture surgery. It is also one of the few studies comparing outcomes with those during the pre-COVID-19 pandemic in a large cohort study. Moreover, there was no patient selection bias because the categorization depended only on the date of surgery. However, we could exclude the direct effect of COVID-19 infection on surgical outcomes in elderly patients undergoing hip fracture surgery because patients who tested positive in the COVID-19 test were transferred to hospitals dedicated to COVID-19 treatment.
CONCLUSION
The current study demonstrated that the delay in the time from injury to hospital visit and from hospital visit to admission during the COVID-19 pandemic led to significant delays in hip fracture surgery for elderly patients. This delay contributed to increased postoperative medical complications and higher 1-year mortality after surgery in these patients. In light of these findings, it is crucial that, in future outbreaks and public health emergencies, expediting the screening process for elderly patients with hip fractures is crucial to facilitate early surgery and subsequently minimize morbidity and mortality risk.
Funding Statement
Funding No funding to declare.
Footnotes
Conflict of Interest
Je-Hyun Yoo has been an Editorial Board member since January 2023, but had no role in the decision to publish this article. No other potential conflict of interest relevant to this article was reported.
References
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