Total Joint Arthroplasty in Nonagenarians: What Are the Risks?

The Journal of Arthroplasty 30 (2015) 2102–2105.e1

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Total Joint Arthroplasty in Nonagenarians: What Are the Risks? Julio J. Jauregui, MD a, Matthew R. Boylan, ScB b,c, Bhaveen H. Kapadia, MD b, Qais Naziri, MD b, Aditya V. Maheshwari, MD b, Michael A. Mont, MD a a b c

Center for Joint Preservation and Reconstruction, Rubin Institute for Advanced Orthopedics, Sinai Hospital of Baltimore, Baltimore, Maryland Department of Orthopaedic Surgery, SUNY Downstate Medical Center, Brooklyn, New York Department of Epidemiology and Biostatistics, SUNY Downstate Medical Center, Brooklyn, New York

a r t i c l e

i n f o

Article history: Received 13 April 2015 Accepted 12 June 2015 Keywords: nonagenarian total joint arthroplasty outcomes complications elderly

a b s t r a c t With recent increases in life expectancy in the United States, the number of nonagenarians (age 90–99 years) presenting for lower extremity joint arthroplasty (TJA) will likely rise. Utilizing the National Surgical Quality Improvement Program database, we compared 30-day outcomes of TJA between nonagenarians and controls (age b90 years). Nonagenarians had lower mean BMI, no difference in mean number of comorbidities, and shorter mean operation time. Compared to controls, nonagenarians had longer mean length-of-stay, higher readmission rate, and higher risk of postoperative adverse events. Given these findings, orthopaedic surgeons should be aware of the increased risks of TJA in nonagenarians, and should discuss these risks with potential surgical candidates during a shared decision-making process. © 2015 Elsevier Inc. All rights reserved.

The elderly population in the United States continues to grow as the mean life expectancy increases secondary to advances in disease prevention and management. According to the National Center for Health Statistics, the nonagenarian population (age of 90–99 years) in the United States has nearly tripled over the past three decades, from 720,000 in 1980 to 1,900,000 in 2010 [1]. This demographic group is projected to continue growing for the foreseeable future, reaching an estimated 9,000,000 persons by the year 2050 [1]. With the dramatic increase in the size of this patient population, and their high risk of osteoarthritis [2], an increasing number of nonagenarians are expected to visit orthopaedic surgeons for lower extremity total joint arthroplasty (TJA) [2–4]. Prior studies of TJA in nonagenarians have shown good functional outcomes postoperatively [3,4]. However, despite the potential benefits, it is generally thought that these patients are at an increased risk of postoperative complications due to multiple medical comorbidities including chronic obstructive pulmonary disease, diabetes, and hypertension [2,5,6], which can delay preoperative optimization and increase the risk of complications postoperatively. Furthermore, elderly patients One or more of the authors of this paper have disclosed potential or pertinent conflicts of interest, which may include receipt of payment, either direct or indirect, institutional support, or association with an entity in the biomedical field which may be perceived to have potential conflict of interest with this work. For full disclosure statements refer to http://dx.doi.org/10.1016/j.arth.2015.06.028. Supplementary material available at www.arthroplastyjournal.org. Reprint requests: Michael A. Mont, MD, Center for Joint Preservation and Replacement, Rubin Institute for Advanced Orthopedics, Sinai Hospital of Baltimore, 2401 West Belvedere Avenue, Baltimore, MD 21215. http://dx.doi.org/10.1016/j.arth.2015.06.028 0883-5403/© 2015 Elsevier Inc. All rights reserved.

have limited physiological reserve to withstand surgical stress and have slower wound healing [7]. However, current studies of the nonagenarian population are limited by small sample sizes drawn from single-institutions [6,8–10]. Therefore, we attempted to address such limitations concerning this topic using a large, nationwide, multi-institution database from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP). We specifically assessed the following metrics for nonagenarians undergoing elective TJA compared to patients less than 90 years undergoing TJA: (1) demographics; (2) preoperative comorbidities; (3) operative related factors; (4) postoperative course, including readmission and length of stay; and (5) risk of postoperative adverse events within 30 days of surgery. The primary goal of our study was to assess the risk of postoperative complications among nonagenarians undergoing TJA. We hypothesized that nonagenarians would be at an increased risk of these postoperative complications.

Methods Study Population The NSQIP collects data on surgical encounters from more than 300 hospitals across the United States [11]. The database contains demographic and clinical variables for each patient, including Current Procedural Terminology (CPT) codes and 30-day postoperative outcomes. The data is devoid of personal identifiers and is freely available to researchers at participating institutions. Therefore, this study did not

J.J. Jauregui et al. / The Journal of Arthroplasty 30 (2015) 2102–2105.e1

meet human subject research criteria and was given exempt status after review by our institutional review board. Cases The study population consisted of 58,126 patients who underwent elective lower extremity total joint arthroplasty between January 2011 and December 2012. Of this cohort, 347 (0.60%) were nonagenarians, with the remaining 57,779 patients serving as the comparison group. There were 22,784 patients (200 nonagenarians) who underwent total hip arthroplasty (CPT 27130), and 35,342 patients (147 nonagenarians) who underwent total knee arthroplasty (CPT 27447) during this time-period. Demographics

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infection, deep surgical site infection, organ or space surgical site infection, urinary tract infection, pneumonia, transfusion, renal insufficiency, graft or prosthesis failure, peripheral nerve injury, or deep vein thrombosis. We defined “any adverse event” as having either a serious or a minor adverse event during the 30-day postoperative follow-up period. Statistical Analysis To compare differences in continuous variables between nonagenarians and other patients, we used means with independent sample t-tests. To compare differences of categorical variables, we used frequency tables with Fisher’s Exact tests for binary variables and chisquared tests for multi-level variables. To compare the risk of adverse events (any, serious, minor) between nonagenarians and other patients, we used logistic regression to calculate the odds ratio (OR) and 95% confidence interval (95% CI) of having an adverse event within 30 days of TJA. Sub-analyses separately assessed the risk of adverse events for THA and TKA. We also stratified our analyses by length of stay (b 7 days, ≥ 7 days) and operative time (b2 hours, ≥ 2 hours). Models were controlled for gender, race, categorical body mass index, and Charlson comorbidity score. All analyses were performed using SAS version 9.4 (SAS Institute Inc., Cary, North Carolina). All P values were twotailed, and P b 0.05 was interpreted as statistically significant.

Data were extracted on each patient’s age (in years), gender, race (Caucasian, African-American, other, unknown), and body mass index (BMI) in kg/m2. Age was categorized according to nonagenarian cutoffs (b90, ≥ 90 years). Body mass index was categorized according to standard ranges for normal weight (b25.0 kg/m 2), overweight (25.0–29.9 kg/m2), class I obesity (30.0–34.9 kg/m2), and class II/III obesity (≥35.0 kg/m 2). Comorbidities were assessed using an adaptation of the Charlson Comorbidity Index for the ACS NSQIP data, as has been done previously [12–14]. Comorbidities (with point value in parentheses) included history of myocardial infarction (1), history of congestive heart failure (1), peripheral vascular disease, intermittent claudication or lower extremity rest pain (1), transient ischemic attack or cerebrovascular accident (1), chronic obstructive pulmonary disease (1), diabetes mellitus (1), hemiplegia (2), end-stage renal disease (2), ascites or esophageal varices (3), and metastatic cancer (6). A patient’s Charlson score was determined as the sum of their comorbidity point values.

Results

Preoperative and Intraoperative Exposures

Preoperative and Intraoperative Exposures

We extracted data on each patient’s procedure type (THA, TKA), functional status prior to surgery (independent, partially, or totally dependent), smoking status (nonsmoker, smoker), American Society of Anesthesiologists (ASA) score, anesthesia type (general, spinal or epidural, regional or local), and the length of surgery. The ASA score was analyzed as a continuous and categorical (b3, ≥ 3) variable. Length of surgery was defined as the total operation time in minutes, from incision to closure. Among the 347 nonagenarians, there were 4 patients with an operative time of 0 minutes, 1 patient with a time of 27 minutes, and 1 patient with a time of 533 minutes. We only considered patients with operation times between 30 and 270 minutes to avoid the confounding effect of outlier values on these variables.

Nonagenarians were more likely to undergo THA (58% vs. 39%) than TKA (42% vs. 61%; P b 0.001) (Table 2). Compared to controls, their preoperative functional status was more likely to be partially or totally dependent (13% vs. 2%; P b 0.001), they were less likely to be current

Postoperative Course We extracted data on each patient’s hospital length of stay. Patients who had a postoperative length of stay greater than 30 days were not analyzed to avoid the confounding effect of outlier values. We also extracted data on each patient’s discharge destinations (home, nursing facility) and readmissions within 30 days (no, yes). Postoperative Adverse Events The ACS NSQIP follows patients for 30 days postoperatively and provides data on 23 unique outcomes. Consistent with prior studies [13,14], we defined a “serious adverse event” as death, coma, failure to wean off of a ventilator, unplanned intubation, cerebrovascular accident, pulmonary embolism, cardiac arrest, myocardial infarction, acute renal failure, sepsis, septic shock, or return to the operating room. We defined a “minor adverse event” as wound disruption, superficial surgical site

Demographics Nonagenarians were more likely to be female (65 vs. 60%; p = 0.042) with a lower mean body mass index (25.6 vs. 31.7 kg/m 2; P b 0.001), and a lower proportion of patients were African American (3% vs. 6%) (Table 1). There was no significant difference in mean Charlson Comorbidity Scores (0.11 vs. 0.10 points; P = 0.596) (Table 1).

Table 1 Patient Demographics for Nonagenarians Compared to Other Patients Undergoing Total Joint Arthroplasty. Age (years) b90 Gender, % Male Female Race, % White Black Other Unknown Body mass index (kg/m2), mean Body mass index (kg/m2), % b25.0 25.0–29.9 30.0–34.9 ≥35.0 Charlson Comorbidity Score, mean Charlson Comorbidity Score, % 0 1 2 ≥3 • Abbreviations: % = percent of patients. • Totals may not add to 100 due to rounding.

≥90

P

40 60

35 65

0.042

80 6 3 12 31.7

81 3 1 16 25.6

0.001

15 31 27 27 0.11

49 36 14 1 0.10

91 8 1 0

90 9 0 0

b0.001 b0.001

0.596 0.437

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Table 2 Preoperative and Surgical Exposures for Nonagenarians Compared to Other Patients Undergoing Total Joint Arthroplasty.

Postoperative Adverse Events

Age (years)

Procedure, % Total hip arthroplasty Total knee arthroplasty Preoperative functional status, % Independent Partially or totally dependent Smoking status, % Nonsmoker Smoker ASA Score, mean ASA Score, % b3 ≥3 Anesthesia type, % General Spinal or epidural Regional or local Operation time (minutes), mean Operating room time (minutes), mean

b90

≥90

P

39 61

58 42

b0.001

98 2

87 13

b0.001

85 15 2.4

94 6 2.7

b0.001

57 43

36 64

b0.001

55 39 6 94.8 139.5

53 40 6 85.2 132.3

b0.001

0.677

b0.001 0.055

• Abbreviations: % = percent of patients. • Totals may not add to 100 due to rounding.

smokers (6% vs. 15%; P b 0.001), they had a higher mean ASA score (2.7 vs. 2.4; P b 0.001), they were more likely to have an ASA score of 3 or more (64% vs. 43%; p b 0.001), they had no difference in type of anesthesia used during surgery (P = 0.677), and they had a shorter mean operation time (85 vs. 95 minutes; P b 0.001) (Table 2).

Postoperative Course The mean postoperative length of stay for nonagenarians was longer than the comparison group (4.4 vs. 3.2 days; P b 0.001) (Fig. 1). This was true for both THA (4.4 vs. 3.1 days; P b 0.001) and TKA (4.4 vs. 3.3 days; P b 0.001). In addition, nonagenarians had higher readmission rate within 30 days (6.9% vs. 3.8%; P = 0.005) (Fig. 1). This was observed for both THA (7.0% vs. 3.6%; P = 0.019) and TKA (6.8% vs. 3.9%; P = 0.083), although the difference for TKA did not reach statistical significance. Nonagenarians were more likely to be discharged to a nursing facility (79% vs. 31%; P b 0.001), which was true for both THA (80% vs. 28%; P b 0.001) and TKA (77% vs. 33%; P b 0.001). Control patients who were discharged to a facility had readmission rate of 5.32%, compared to 3.07% among patients discharged home (P b 0.001). However, this

Control

association was not observed among nonagenarians (readmission rate of 6.64% for nursing facility vs. 6.94% for home; P = 0.927).

Serious postoperative adverse events that were significantly higher in nonagenarians compared to controls included death (0.9% vs. 0.2%; P = 0.024), unplanned intubation (1.2% vs. 0.2%; P = 0.004), cerebrovascular accident (0.6% vs. 0.1%; P = 0.039), and myocardial infarction (1.7% vs. 0.3%; P b 0.001). Significantly more frequent minor adverse events included urinary tract infection (2.9% vs. 1.1%; P = 0.006), pneumonia (1.2% vs. 0.3%; P = 0.031), and transfusion (41.2% vs. 17.4%; P b 0.001). A full listing of the frequency of specific adverse events for both nonagenarians and reference control patients within 30 days of surgery can be found in the Appendices A, B & C. In regression models adjusted for gender, race, body mass index, and Charlson comorbidity score, the risk of any adverse event was 163% higher for nonagenarians compared to other patients (OR = 2.63; 95% CI = 2.12–3.26; P b 0.001) (Fig. 2). This association was significant for nonagenarians undergoing both THA (P b 0.001) and TKA (P b 0.001). We noted that the magnitude of this risk was higher for nonagenarians undergoing THA (OR = 3.39; 95% CI = 2.55–4.51) than nonagenarians undergoing TKA (OR = 1.81; 95% CI = 1.29–2.55). When stratified by length of stay, the risk of any adverse event was similar for nonagenarians with a length of stay of less than 7 days (OR = 2.38; 95% CI = 1.88–3.00; P b 0.001) and 7 or more days (OR = 2.40; 95% CI, 1.23–4.71; P = 0.011). When stratified by operative time, the risk was also similar between nonagenarians with an operative time of less than 2 hours (OR = 2.62; 95% CI = 2.08–3.30; P b 0.001) and 2 or more hours (OR = 3.31; 95% CI = 1.80–6.06; P b 0.001). The risk of a serious adverse event was 160% higher for nonagenarians (OR = 2.60; 95% CI = 1.68–4.03; P b 0.001) (Fig. 2). This association, however, was specific for THA (OR = 3.84; 95% CI = 2.33–6.32; P b 0.001) and not for TKA (OR = 1.05; 95% CI = 0.39–2.86; P = 0.921). The risk of a minor adverse event was 158% higher for nonagenarians (OR = 2.58; 95% CI = 2.08–3.21; P b 0.001) (Fig. 2). The magnitude of this association was stronger for THA (OR = 3.16; 95% CI = 2.37–4.20; P b 0.001) than TKA (OR = 1.89; 95% CI = 1.34–2.67; P b 0.001). Discussion Recent advances in health care have dramatically increased the life expectancy in the United States and abroad, and the number of the nonagenarians undergoing lower extremity TJA in the coming years is expected to increase [6,15]. Our study’s primary goal was to assess the risk of postoperative complications of nonagenarians undergoing TJA, as there is

Nonagenarian

Any Adverse Event

8

Serious Adverse Event

Minor Adverse Event

6

7

5

Odds Ratio

6 5 4 3 2

4 3 2 1

1 0

0 Mean Length of Stay (Days)

Readmitted Within 30 Days (%)

Type of Surgery Fig. 1. Length of stay and readmission rates for nonagenarians compared to other patients undergoing total joint arthroplasty.

TJA

THA

TKA

Type of Surgery Fig. 2. Risk of adverse events for nonagenarians compared to other patients undergoing total joint arthroplasty.

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limited existing data on this topic. We hypothesized that nonagenarians would be at an increased risk of postoperative complications, and found that these patients had a longer mean length-of-stay, a higher readmission rate, and a 163% higher risk of a postoperative adverse event. Our finding of nonagenarians having a longer mean length of stay than other patients undergoing TJA is consistent with prior studies. In smaller studies of nonagenarians undergoing TJA, the mean lengths of stay were 11.0 days [2] and 7.5 days [16] for TKA, and 7.0 days for THA [16]. In a pair of database studies, Miric et al. [17,18] found that nonagenarians had a mean length of stay of 3.3 days for TKA and 3.4 days for THA, which was significantly longer than the 3.0 days in TKA controls and 2.8 days in THA controls. In addition, Bradley et al. [19] found that the length of stay increased by 13 % with each 10-year increase in age. Nonagenarians had an increased risk of adverse events within 30 days of surgery, including death, unplanned intubation, cerebrovascular accident, myocardial infarction, urinary tract infection, pneumonia, and transfusion. In a prior study of octogenarians undergoing TKA, Kennedy et al. [4] found a significantly higher complication rate among octogenarians compared to controls. Individual complications that were more frequent included myocardial infarction, periprosthetic fracture, and tibiofemoral dislocation. Furthermore, Miric et al. [17,18] found that nonagenarians had an increased risk of readmission within 30 and 90 days as well as death within 30, 90, and 365 days. Regarding nonagenarians increased risk of transfusion, a prior study of THA found that the risk of transfusion increased by a factor for 10 for each 10-year increase in patient age [19]. This may be explained by the findings that elderly patients have a higher prevalence of anemia compared to younger patients [20], and preoperative anemia is associated with an increased risk of transfusion during admission [21]. For nonagenarians, comorbidities have been previously associated with an increased risk of complications. Among nonagenarians undergoing TJA, Joshi et al. [15] found that cardiac risk factors were associated with increased postoperative morbidity and mortality, while Alfonso et al. [22] reported a 36% postoperative cardiac complication rate. In a long-term follow-up of 15 nonagenarians undergoing TKA, Belmar et al. [3] reported that the majority of postoperative complications were a result of preoperative medical conditions. However, despite these findings, we observed no significant difference in the mean Charlson Comorbidity score for nonagenarians compared to controls. This may be secondary to a selection bias for nonagenarians undergoing TJA, as they may be generally healthier than age-matched peers. In a prior study, functional limitations, rather than chronic conditions, were the strongest predictors of mortality among elderly patients [23], potentially explaining the increased risks of TJA among nonagenarians despite no difference in comorbidities. We found that nonagenarians had a mean operative time that was 10 minutes shorter compared to controls. Although we cannot prove cause and effect, this difference in operative time may be associated with the mean BMI that was 6-units lower in nonagenarians compared to controls. Gandinsky et al. [24] found that increased TKA surgical time was associated with increased BMI, while Bradley et al. [25] found that TKA operative time increased by 7 minutes for each 5-point increase in patient BMI. This study has several limitations that should be noted. The NSQIP dataset does not contain data on postoperative complications beyond 30 days, short- or long-term functional outcomes, or TJA-specific complications including prosthesis loosening, revision surgery, joint dislocation, and periprosthetic fracture. The database also has limited data on the patient’s short-term management, including prophylaxis against venous thromboembolism and infection, surgical approach, implant type, and postoperative rehabilitation. Furthermore, we were unable to determine the causes for patients with a prolonged length of surgery or length of stay, and we were unable to identify patients who received bilateral or additional joint replacements during the 30-day postoperative period. We were also limited by a relatively small sample size of

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nonagenarians undergoing TJA, as we were unable to assess specific risk factors for adverse events among these patients. Nevertheless, our present study represents one of the largest and most comprehensive analyses to date of nonagenarians undergoing TJA. In conclusion, with rises in life expectancy, nonagenarians are a rapidly growing demographic that will likely have a growing demand for lower extremity TJA in the coming years. While TJA can improve quality of life for nonagenarians, orthopaedic surgeons should be aware of the risks of performing surgery on these patients. Using a large, nationwide database, we found that the risks of postoperative adverse events following elective TJA, particularly THA, were significantly higher for nonagenarians compared to a control group. These associations remained significant after controlling for potential confounders including gender, race, body mass index, and comorbidities. Surgeons should discuss these risks with potential nonagenarian TJA candidates as part of a shared decision making process about surgery. References 1. He Wan, Muenchrath Mark N. ACS-17, 90+ in the United States: 2006–2008; 2011. 2. Karuppiah SV, Banaszkiewicz PA, Ledingham WM. The mortality, morbidity and cost benefits of elective total knee arthroplasty in the nonagenarian population. Int Orthop 2008;32:339. 3. Belmar CJ, Barth P, Lonner JH, et al. Total knee arthroplasty in patients 90 years of age and older. J Arthroplasty 1999;14:911. 4. Kennedy JW, Johnston L, Cochrane L, et al. Total knee arthroplasty in the elderly: does age affect pain, function or complications? Clin Orthop Relat Res 2013;471:1964. 5. Hernandez-Vaquero D, Fernandez-Carreira JM, Perez-Hernandez D, et al. Total knee arthroplasty in the elderly. Is there an age limit? J Arthroplasty 2006;21:358. 6. Nanjayan SK, Swamy GN, Yellu S, et al. In-hospital complications following primary total hip and knee arthroplasty in octogenarian and nonagenarian patients. J Orthop Traumatol 2014;15:29. 7. Gerstein AD, Phillips TJ, Rogers GS, et al. Wound healing and aging. Dermatol Clin 1993;11:749. 8. Rade MC, Yadeau JT, Ford C, et al. Postoperative delirium in elderly patients after elective hip or knee arthroplasty performed under regional anesthesia. HSS J 2011;7:151. 9. Peersman G, Laskin R, Davis J, et al. Prolonged operative time correlates with increased infection rate after total knee arthroplasty. HSS J 2006;2:70. 10. D'Apuzzo MR, Pao AW, Novicoff WM, et al. Age as an independent risk factor for postoperative morbidity and mortality after total joint arthroplasty in patients 90 years of age or older. J Arthroplasty 2014;29:477. 11. American College of Surgeons National Surgical Quality Improvement Program. ACS NSQIP. American College of Surgeons; 2015[http://www.acsnsqip.org/]. 12. Charlson ME, Pompei P, Ales KL, et al. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis 1987;40:373. 13. Ehlert BA, Nelson JT, Goettler CE, et al. Examining the myth of the "July Phenomenon" in surgical patients. Surgery 2011;150:332. 14. Bohl DD, Basques BA, Golinvaux NS, et al. Extramedullary compared with intramedullary implants for intertrochanteric hip fractures: thirty-day outcomes of 4432 procedures from the ACS NSQIP database. J Bone Joint Surg Am 2014;96:1871. 15. Joshi AB, Gill G. Total knee arthroplasty in nonagenarians. J Arthroplasty 2002;17:681. 16. Berend ME, Thong AE, Faris GW, et al. Total joint arthroplasty in the extremely elderly: hip and knee arthroplasty after entering the 89th year of life. J Arthroplasty 2003;18:817. 17. Miric A, Inacio MC, Kelly MP, et al. Can total knee arthroplasty be safely performed among nonagenarians? An evaluation of morbidity and mortality within a total joint replacement registry. J Arthroplasty 2014;29:1635. 18. Miric A, Inacio MC, Kelly MP, et al. Are nonagenarians too old for total hip arthroplasty? An evaluation of morbidity and mortality within a total joint replacement registry. J Arthroplasty 2015. http://dx.doi.org/10.1016/j.arth.2015.03.008. 19. Hart A, Khalil JA, Carli A, et al. Blood transfusion in primary total hip and knee arthroplasty. Incidence, risk factors, and thirty-day complication rates. J Bone Joint Surg Am 2014;96:1945. 20. Bach V, Schruckmayer G, Sam I, et al. Prevalence and possible causes of anemia in the elderly: a cross-sectional analysis of a large European university hospital cohort. Clin Interv Aging 2014;9:1187. 21. Jans O, Jorgensen C, Kehlet H, et al. Role of preoperative anemia for risk of transfusion and postoperative morbidity in fast-track hip and knee arthroplasty. Transfusion 2014;54:717. 22. Alfonso DT, Howell RD, Strauss EJ, et al. Total hip and knee arthroplasty in nonagenarians. J Arthroplasty 2007;22:807. 23. Lee SJ, Go AS, Lindquist K, et al. Chronic conditions and mortality among the oldest old. Am J Public Health 2008;98:1209. 24. Gadinsky NE, Manuel JB, Lyman S, et al. Increased operating room time in patients with obesity during primary total knee arthroplasty: conflicts for scheduling. J Arthroplasty 2012;27:1171. 25. Bradley BM, Griffiths SN, Stewart KJ, et al. The effect of obesity and increasing age on operative time and length of stay in primary hip and knee arthroplasty. J Arthroplasty 1906;29.

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Appendix A. Preoperative and Surgical Exposures for Nonagenarians Compared to Other Patients Undergoing Total Joint Arthroplasty

Appendix C. Risk of Adverse Events Within 30 Days of Total Joint Arthroplasty for Nonagenarians Compared to Other Patients

Age (years)

Postoperative length of stay (days), mean THA TKA Discharged to nursing facility†, % THA TKA Readmitted within 30 days, % THA TKA

b90

≥90

P

3.2 3.1 3.3 31 28 33 3.8 3.6 3.9

4.4 4.4 4.4 79 80 77 6.9 7.0 6.8

b0.001 b0.001 b0.001 b0.001 b0.001 b0.001 0.005 0.019 0.083

• Abbreviations: % = percent of patients. • Totals may not add to 100 due to rounding. † Patient were discharged either to home or a nursing facility.

Appendix B. Frequency of Specific Adverse Events Within 30 Days of Total Joint Arthroplasty for Nonagenarians and Other Patients Age (years) b90 (N = 57,779) N Serious adverse events Death Coma Failure to wean off ventilator Unplanned intubation Cerebrovascular accident Pulmonary embolism Cardiac arrest Myocardial infarction Acute renal failure Sepsis Septic shock Return to the operating room

100 1 41 103 50 284 58 156 46 159 30 861

Minor adverse events Wound disruption Superficial surgical site infection Deep surgical site infection Organ/space surgical site infection Urinary tract infection Pneumonia Transfusion Renal insufficiency Graft or prosthesis Failure Peripheral nerve injury Deep vein thrombosis

89 411 111 100 631 193 10,031 70 6 16 413

≥90 (N = 347)

% 0.2 0.0 0.1 0.2 0.1 0.5 0.1 0.3 0.1 0.3 0.1 1.5

0.2 0.7 0.2 0.2 1.1 0.3 17.4 0.1 0.0 0.0 0.7

N 3 0 0 4 2 4 1 6 0 3 1 5

0 2 1 1 10 4 143 1 0 0 5

%

P

0.9 0.0 0.0 1.2 0.6 1.2 0.3 1.7 0.0 0.9 0.3 1.4

0.024 N/A N/A 0.004 0.039 0.095 0.298 b0.001 N/A 0.074 0.169 0.999

0.0 0.6 0.3 0.3 2.9 1.2 41.2 0.3 0.0 0.0 1.4

N/A 0.999 0.489 0.454 0.006 0.031 b0.001 0.347 N/A N/A 0.107

Abbreviations: N = number of patients, % = percent of patients, N/A = cannot calculate.

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Any THA TKA Serious THA TKA Minor THA TKA

Risk†

P

2.63 (2.12–3.26) 3.39 (2.55–4.51) 1.81 (1.29–2.55) 2.60 (1.68–4.03) 3.84 (2.33–6.32) 1.05 (0.39–2.86) 2.58 (2.08–3.21) 3.16 (2.37–4.20) 1.89 (1.34–2.67)

b0.001 b0.001 b0.001 b0.001 b0.001 0.921 b0.001 b0.001 b0.001

• Abbreviations: THA = total hip arthroplasty; TKA = total knee arthroplasty. † Patient were discharged either to home or a nursing facility.