Keywords
total knee arthroplasty - human immunodeficiency virus - acquired immunodeficiency
syndrome - postoperative complications - medical complications - surgical complications
With the average age of the United States population increasing, there is projected
to be a large increase in arthritis cases to 67 million cases by 2030.[1] The most common cause of arthritis is osteoarthritis (OA), which currently affects
27 million adults.[2] The knee joint is the most affected joint; consequently,[3] total knee arthroplasty (TKA) is one of the most frequently performed surgical procedures.
Patients diagnosed with human immunodeficiency virus (HIV) may be at additional risk
for developing postoperative complications following TKA.[4]
[5] In the United States, over 1.1 million people are living with HIV, including an
estimated 21% of whom are undiagnosed.[6] With the advent of highly active antiretroviral therapies (HAARTs), HIV-positive
patients are living much longer than they had historically. As the average age for
this patient population increases, the demand for TKA will increase due to age-associated
joint degeneration.[7] This necessitates an understanding of how HIV affects perioperative and postoperative
complications following TKA.
Multiple studies have attempted to analyze the postoperative complications of TKA
in patients with HIV[7]
[8]
[9]; however, the literature is variable. Although some studies indicate that HIV-positive
status alone is not a risk factor for increased complications following TKA,[7]
[10]
[11] other studies report that individuals with HIV may be at increased risk for perioperative
complications.[4]
[5] Because some prior studies included subjects with both hemophilia and HIV, the data
are subject to confounding.[12]
[13]
[14] Prior studies have also been limited by short-term follow-up and lack of subject
stratification into HIV and acquired immunodeficiency syndrome (AIDS) cohorts,[15] which is an important distinction relative to the patient's immune status.
This study aimed to analyze the 90-day complications and 2-year postoperative surgical
complications of patients with HIV who underwent TKA for OA. Our hypothesis was that
patients with HIV, particularly patients with AIDS, would have significantly increased
90-day complication rates and higher risk of revision, particularly for prosthetic
joint infection (PJI), at 2 years postoperatively.
Methods
Data Source and Collection
The PearlDiver Patient Records Database (www.pearldiverinc.com; Colorado Springs, CO) was used to perform a retrospective cohort analysis. Specifically,
the Mariner dataset was utilized, including all-payer claim information for over 121
million patients from 2010 to 2019. Patients who underwent primary TKA were identified
using International Classification of Diseases (ICD) procedure codes as well as Current
Procedural Terminology (CPT) codes. Only patients with 2 years of follow up and who
underwent primary TKA for knee OA were included in this study. The Mariner dataset
provides active longitudinal follow-up based upon unique patient identifier codes
that are not limited to changes in insurance status, minimizing loss to follow-up
in the system. Therefore, patients with 2 years of follow up data included any patient
with insurance continued coverage 2 years following TKA.
Exclusion and Inclusion Criteria
Patients with a diagnosis of HIV were identified using ICD 9/10 diagnosis codes. These
patients were further subcategorized as having AIDS (ICD-9-D-042 and ICD-10-D-V08)
or asymptomatic HIV (AHIV; ICD-9-D-B20 and ICD-10-D-Z21). The control group consisted
of patients who underwent TKA for OA with no known diagnosis of HIV. Patients who
were less than 18 years of age or had a staged or simultaneous bilateral TKA were
excluded. Staged/bilateral TKAs were excluded to confirm that revision outcomes were
from the primary TKA since CPT modifier codes are not present in the PearlDiver database.
The flow chart documenting which PearlDiver patients were included in the present
study is shown in [Fig. 1].
Fig. 1 Flow chart of PearlDiver patients included in the study.
Demographics/Comorbidities and Outcome Variables
Patient demographic and comorbidities observed included age, gender, and Elixhauser
Comorbidity Index comorbidities[16] (congestive heart failure, arrhythmias, valvular disease, pulmonary circulatory
disorders, peripheral vascular disease, hypertension, paralysis, other neuro disorders,
chronic obstructive pulmonary disease, diabetes, hypothyroidism, chronic kidney disease,
liver disease, peptic ulcer disease, lymphoma, metastatic cancer, nonmetastatic cancer,
rheumatoid arthritis and cardiovascular disease, coagulopathy, fluid and electrolyte
disorders, anemia due to blood loss, anemia due to deficiency, alcohol abuse, drug
abuse, psychoses, depression, obesity, and smoking status). These were identified
using ICD-9 and ICD-10 diagnosis codes. The primary outcomes of this study included
90-day postoperative complications: acute renal failure, surgical site infection (SSI),
anemia, arrhythmia with and without atrial fibrillation, blood transfusion, bleeding
complications, deep vein thrombosis (DVT), pulmonary thrombosis, stroke, heart failure,
respiratory complications, pneumonia, urinary tract infection, sepsis, and death.
The secondary outcome of this study was the 2-year complication rate, which included
manipulation under anesthesia (MUA), all-cause revision, revision for peri-PJI, and
revision for aseptic loosening.
Univariate/Multivariable Analysis
Patient data on demographics, comorbidities, and postoperative complications were
analyzed using univariate and multivariable analysis via R software (https://www.R-project.org/, R Foundation for Statistical Computing, Vienna, Austria) provided by PearlDiver.
Univariate analysis was conducted using Chi-squared and Student's t-tests where appropriate. Demographics and comorbidities with a p-value less than 0.2 on univariate analysis were included as independent variables
in multivariable regression for postoperative complications. Results from the multivariable
analysis were reported as odds ratios (ORs) and 95% confidence intervals (CIs). A
p-value of 0.05 was used as the threshold level for significance.
Results
Study Cohort
In total, 855,373 patients who underwent TKA for a primary diagnosis of OA were included
in this study. A total of 1,606 patients (0.19%) undergoing TKA for OA had a diagnosis
of HIV at the time of their procedure. Of those, 1,338 patients (83.3%) had a diagnosis
of AHIV at the time of TKA and 268 patients (16.68%) had a diagnosis of AIDS at the
time of TKA. Demographics and comorbidities are detailed in [Table 1].
Table 1
Demographics and comorbidities of patients undergoing total knee arthroplasty
|
HIV
|
AHIV
|
AIDS
|
Control
|
|
Number
|
Percent (%)
|
p-Value
|
Number
|
Percent (%)
|
p-Value
|
Number
|
Percent (%)
|
p-Value
|
Number
|
Percent (%)
|
Total
|
1,606
|
|
|
1,338
|
|
|
268
|
|
|
853,767
|
|
Age (y)
|
58.76
|
|
<0.001
|
59.04
|
|
<0.001
|
57.31
|
|
<0.001
|
65.75
|
|
Gender
|
|
|
<0.001
|
|
|
<0.001
|
|
|
<0.001
|
|
|
Male
|
767
|
47.76%
|
|
627
|
46.86%
|
|
140
|
52.24%
|
|
312,607
|
36.62%
|
Female
|
839
|
52.24%
|
|
711
|
53.14%
|
|
128
|
47.76%
|
|
541,160
|
63.38%
|
CHF
|
359
|
22.35%
|
<0.001
|
310
|
23.17%
|
<0.001
|
49
|
18.28%
|
0.326
|
135,780
|
15.90%
|
Arrhythmias
|
730
|
45.45%
|
<0.001
|
606
|
45.29%
|
<0.001
|
124
|
46.27%
|
0.008
|
325,760
|
38.16%
|
Valvular disease
|
415
|
25.84%
|
<0.001
|
365
|
27.28%
|
<0.001
|
50
|
18.66%
|
0.159
|
191,524
|
22.43%
|
Pulmonary disorders
|
172
|
10.71%
|
<0.001
|
148
|
11.06%
|
<0.001
|
24
|
8.96%
|
0.562
|
66,743
|
7.82%
|
PVD
|
532
|
33.13%
|
<0.001
|
460
|
34.38%
|
<0.001
|
72
|
26.87%
|
0.109
|
192,772
|
22.58%
|
HTN
|
1,227
|
76.40%
|
<0.001
|
1,040
|
77.73%
|
<0.001
|
187
|
69.78%
|
0.501
|
613,115
|
71.81%
|
Paralysis
|
60
|
3.74%
|
<0.001
|
49
|
3.66%
|
<0.001
|
11
|
4.10%
|
0.041
|
18,108
|
2.12%
|
Other neuro disorders
|
206
|
12.83%
|
<0.001
|
170
|
12.71%
|
<0.001
|
36
|
13.43%
|
<0.001
|
62,413
|
7.31%
|
CPD
|
845
|
52.62%
|
<0.001
|
704
|
52.62%
|
<0.001
|
141
|
52.61%
|
<0.001
|
285,665
|
33.46%
|
Diabetes mellitus
|
791
|
49.25%
|
<0.001
|
690
|
51.57%
|
<0.001
|
101
|
37.69%
|
0.577
|
306,206
|
35.87%
|
Hypothyroidism
|
398
|
24.78%
|
0.019
|
345
|
25.78%
|
0.019
|
53
|
19.78%
|
0.002
|
245,347
|
28.74%
|
CKD
|
396
|
24.66%
|
<0.001
|
331
|
24.74%
|
<0.001
|
65
|
24.25%
|
0.012
|
154,788
|
18.13%
|
Liver disease
|
635
|
39.54%
|
<0.001
|
538
|
40.21%
|
<0.001
|
97
|
36.19%
|
<0.001
|
114,618
|
13.42%
|
PUD
|
58
|
3.61%
|
<0.001
|
49
|
3.66%
|
<0.001
|
9
|
3.36%
|
0.194
|
17,483
|
2.05%
|
Rheumatoid arthritis and CVD
|
365
|
22.73%
|
<0.001
|
317
|
23.69%
|
<0.001
|
48
|
17.91%
|
0.872
|
148,146
|
17.35%
|
Coagulopathy
|
243
|
15.13%
|
<0.001
|
198
|
14.80%
|
<0.001
|
45
|
16.79%
|
<0.001
|
63,431
|
7.43%
|
Fluid and electrolyte disorders
|
712
|
44.33%
|
<0.001
|
579
|
43.27%
|
<0.001
|
133
|
49.63%
|
<0.001
|
262,490
|
30.74%
|
Blood loss anemia
|
121
|
7.53%
|
<0.001
|
100
|
7.47%
|
<0.001
|
21
|
7.84%
|
0.065
|
43,999
|
5.15%
|
Deficiency anemia
|
442
|
27.52%
|
<0.001
|
382
|
28.55%
|
<0.001
|
60
|
22.39%
|
0.023
|
144,937
|
16.98%
|
Alcohol abuse
|
70
|
4.36%
|
<0.001
|
63
|
4.71%
|
<0.001
|
7
|
2.61%
|
0.011
|
8,000
|
0.94%
|
Drug abuse
|
484
|
30.14%
|
<0.001
|
396
|
29.60%
|
<0.001
|
88
|
32.84%
|
<0.001
|
50,616
|
5.93%
|
Psychoses
|
179
|
11.15%
|
<0.001
|
153
|
11.43%
|
<0.001
|
26
|
9.70%
|
<0.001
|
28,216
|
3.30%
|
Depression
|
886
|
55.17%
|
<0.001
|
717
|
53.59%
|
<0.001
|
169
|
63.06%
|
<0.001
|
285,586
|
33.45%
|
Obesity
|
678
|
42.22%
|
<0.001
|
563
|
42.08%
|
<0.001
|
115
|
42.91%
|
<0.001
|
252,169
|
29.54%
|
Smoking
|
629
|
39.17%
|
<0.001
|
509
|
38.04%
|
<0.001
|
120
|
44.78%
|
<0.001
|
108,159
|
12.67%
|
Abbreviations: BMI, body mass index; CHF, congestive heart failure; CKD, chronic kidney
disease; COPD, chronic obstructive pulmonary disorder; CVD, collagen vascular disease;
HTN, hypertension; PUD, peptic ulcer disease; PVD, peripheral vascular disease.
Note: All p-Value comparisons made between group of interest and control group; statistically
significant p-values (p < 0.05) are indicated in bold.
Two-Year Surgical Complications
A total of 2.9% of patients with HIV (46 patients), of whom 85% (39 patients) had
AHIV and 15% (7 patients) had AIDS, underwent revision TKA within 2 years of the initial
procedure. This was significant compared with 1.8% of patients in the non-HIV cohort
who required revision at this time point (p = 0.002). Patients with AHIV had a higher risk of PJI (p < 0.001), aseptic loosening (p = 0.011), and MUA (p < 0.001) than patients without HIV. Patients with AIDS were only at an increased
risk for PJI (p = 0.002) compared with the control group. The breakdown of patients who had surgical
complications is displayed in [Table 2].
Table 2
Two-year surgical complications following total knee arthroplasty
|
HIV
|
AHIV
|
AIDS
|
Control
|
|
Number
|
Percent (%)
|
p-Value
|
Number
|
Percent (%)
|
p-Value
|
Number
|
Percent (%)
|
p-Value
|
Number
|
Percent (%)
|
Total
|
1,606
|
|
|
1,338
|
|
|
268
|
|
|
853,767
|
|
Revision
|
46
|
2.86%
|
0.002
|
39
|
2.91%
|
0.004
|
7[a]
|
2.61%
|
0.460
|
15,552
|
1.82%
|
PJI
|
25
|
1.56%
|
<0.001
|
19
|
1.42%
|
<0.001
|
6[a]
|
2.24%
|
0.002
|
5,038
|
0.59%
|
Loosening
|
10[a]
|
0.62%
|
0.050
|
10[a]
|
0.75%
|
0.011
|
0
|
0.00%
|
0.705
|
2,704
|
0.32%
|
MUA
|
103
|
6.41%
|
<0.001
|
86
|
6.43%
|
<0.001
|
17
|
6.34%
|
0.084
|
34,748
|
4.07%
|
Abbreviations: MUA, manipulation under anesthesia; PJI, prosthetic joint infection.
Note: Groups were analyzed with chi-squared analysis compared with the control group.
Statistically significant p-Values (p < 0.05) are indicated in bold.
a Per HIPAA requirements, <11 cohort sizes are not reportable.
However, on multivariable analysis, neither the AHIV nor the AIDS group was found
to be at greater or lesser odds of 2-year revision surgery, PJI, aseptic loosening,
or MUA compared with the control cohort. The ORs and CIs for all cohorts are shown
in [Table 3].
Table 3
Multivariable analysis of 2-year complications and 90-day complications following
total knee arthroplasty
|
HIV
|
AHIV
|
AIDS
|
|
Odds ratio
|
25%
|
75%
|
p-Value
|
Odds ratio
|
25%
|
75%
|
p-Value
|
Odds ratio
|
25%
|
75%
|
p-Value
|
2-year complications
|
Revision
|
0.842
|
0.618
|
1.119
|
0.257
|
0.872
|
0.622
|
1.186
|
0.405
|
–
|
–
|
–
|
–
|
PJI
|
1.237
|
0.807
|
1.805
|
0.298
|
1.139
|
0.695
|
1.748
|
0.578
|
1.639
|
0.643
|
3.397
|
0.236
|
Loosening
|
1.013
|
0.505
|
1.790
|
0.968
|
1.240
|
0.618
|
2.192
|
0.502
|
1.146
|
0.672
|
1.823
|
0.590
|
MUA
|
1.220
|
0.991
|
1.486
|
0.054
|
1.234
|
0.982
|
1.530
|
0.063
|
–
|
–
|
–
|
–
|
90-day complications
|
SSI
|
1.113
|
0.828
|
1.461
|
0.459
|
1.076
|
0.773
|
1.455
|
0.648
|
1.257
|
0.620
|
2.254
|
0.483
|
Renal failure
|
1.153
|
0.876
|
1.491
|
0.292
|
0.958
|
0.691
|
1.292
|
0.786
|
2.129
|
1.239
|
3.451
|
0.004
|
Anemia
|
–
|
–
|
–
|
–
|
0.697
|
0.587
|
0.821
|
<0.001
|
1.516
|
1.123
|
2.018
|
0.005
|
Arrhythmia w/ atrial fibrillation
|
0.814
|
0.668
|
0.984
|
0.037
|
0.813
|
0.655
|
1.000
|
0.055
|
–
|
–
|
–
|
–
|
Arrhythmia w/o atrial fibrillation
|
1.304
|
1.068
|
1.579
|
0.008
|
1.257
|
1.006
|
1.553
|
0.039
|
1.541
|
0.964
|
2.367
|
0.058
|
Bleeding complication
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
1.666
|
0.591
|
3.651
|
0.262
|
Blood transfusion
|
0.931
|
0.726
|
1.175
|
0.559
|
0.855
|
0.645
|
1.111
|
0.259
|
1.302
|
0.746
|
2.112
|
0.317
|
Pneumonia
|
1.318
|
0.946
|
1.783
|
0.087
|
1.094
|
0.736
|
1.559
|
0.638
|
2.473
|
1.299
|
4.265
|
0.003
|
Stroke
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
Death
|
1.179
|
0.466
|
2.415
|
0.689
|
1.151
|
0.410
|
2.500
|
0.755
|
–
|
–
|
–
|
–
|
DVT
|
1.085
|
0.813
|
1.416
|
0.563
|
1.054
|
0.765
|
1.413
|
0.736
|
1.210
|
0.596
|
2.176
|
0.561
|
Heart failure
|
0.912
|
0.689
|
1.188
|
0.505
|
0.885
|
0.652
|
1.178
|
0.416
|
–
|
–
|
–
|
–
|
Pulmonary embolism
|
1.232
|
0.832
|
1.757
|
0.273
|
1.173
|
0.756
|
1.737
|
0.450
|
–
|
–
|
–
|
–
|
Respiratory complication
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
Sepsis
|
1.294
|
0.843
|
1.891
|
0.209
|
1.301
|
0.813
|
1.962
|
0.239
|
1.206
|
0.370
|
2.863
|
0.713
|
UTI
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
–
|
Abbreviations: DVT, deep vein thrombosis; MUA, manipulation under anesthesia; PJI,
prosthetic joint infection; SSI, surgical site infection; UTI, urinary tract infection;
w/ atrial fibrillation, with atrial fibrillation; w/o atrial fibrillation, without
atrial fibrillation.
Note: Groups were analyzed with chi-squared analysis compared with control group.
Statistically significant p-Values (p < 0.05) are indicated in bold.
Ninety-Day Medical Complications
On univariate analysis, patients with AHIV were found to be at an increased risk of
several minor 90-day complications such as SSIs (p < 0.001), arrhythmia without atrial fibrillation (p = 0.002), and pneumonia (p = 0.004) as well as major 90-day complications such as renal failure (p = 0.024) and sepsis (p < 0.001). Patients with AIDS were also at an increased risk of several 90-day complications
including SSI (p = 0.007), anemia (p < 0.001), arrhythmia without atrial fibrillation (p < 0.001), bleeding complications (p = 0.024), DVT (p = 0.111), and pneumonia (p < 0.001). This cohort of patients was also at an increased risk of renal failure
(p < 0.001) and sepsis (p = 0.187) within 90 days following TKA ([Table 4]).
Table 4
90-Day complications following total knee arthroplasty
|
HIV
|
AHIV
|
AIDS
|
Control
|
|
Number
|
Percent (%)
|
p-Value
|
Number
|
Percent (%)
|
p-Value
|
Number
|
Percent (%)
|
p-Value
|
Number
|
Percent (%)
|
Total
|
1,606
|
|
|
1,338
|
|
|
268
|
|
|
853,767
|
|
SSI
|
51
|
3.18%
|
<0.001
|
41
|
3.06%
|
<0.001
|
10
|
3.73%
|
0.007
|
13,056
|
1.53%
|
Renal failure
|
62
|
3.86%
|
<0.001
|
44
|
3.29%
|
0.024
|
18
|
6.72%
|
<0.001
|
19,808
|
2.32%
|
Anemia
|
222
|
13.82%
|
0.886
|
161
|
12.03%
|
0.089
|
61
|
22.76%
|
<0.001
|
116,699
|
13.67%
|
Arrhythmia with atrial fibrillation
|
130
|
8.09%
|
0.029
|
109
|
8.15%
|
0.055
|
21
|
7.84%
|
0.343
|
83,173
|
9.74%
|
Arrhythmia without atrial fibrillation
|
123
|
7.66%
|
<0.001
|
99
|
7.40%
|
0.002
|
24
|
8.96%
|
0.016
|
46,304
|
5.42%
|
Bleeding complication
|
14
|
0.87%
|
0.227
|
9[a]
|
0.67%
|
0.891
|
5[a]
|
1.87%
|
0.024
|
5,174
|
0.61%
|
Blood transfusion
|
73
|
4.55%
|
0.070
|
57
|
4.26%
|
0.277
|
16
|
5.97%
|
0.065
|
31,279
|
3.66%
|
Pneumonia
|
41
|
2.55%
|
<0.001
|
29
|
2.17%
|
0.004
|
12
|
4.48%
|
<0.001
|
10,749
|
1.26%
|
Stroke
|
18
|
1.12%
|
0.247
|
14
|
1.05%
|
0.464
|
4[a]
|
1.49%
|
0.387
|
7,064
|
0.83%
|
Death
|
6[a]
|
0.37%
|
0.088
|
5[a]
|
0.37%
|
0.133
|
1[a]
|
0.37%
|
0.941
|
1,434
|
0.17%
|
DVT
|
54
|
3.36%
|
0.001
|
44
|
3.29%
|
0.005
|
10[a]
|
3.73%
|
0.111
|
18,248
|
2.14%
|
Heart failure
|
64
|
3.99%
|
0.086
|
54
|
4.04%
|
0.097
|
10[a]
|
3.73%
|
0.748
|
27,316
|
3.20%
|
Pulmonary embolism
|
31
|
1.93%
|
0.014
|
25
|
1.87%
|
0.044
|
6[a]
|
2.24%
|
0.218
|
10,457
|
1.22%
|
Respiratory complication
|
10[a]
|
0.62%
|
0.930
|
9[a]
|
0.67%
|
1.000
|
1[a]
|
0.37%
|
0.822
|
5,736
|
0.67%
|
Sepsis
|
25
|
1.56%
|
<0.001
|
21
|
1.57%
|
<0.001
|
4[a]
|
1.49%
|
0.187
|
5,594
|
0.66%
|
UTI
|
100
|
6.23%
|
0.515
|
87
|
6.50%
|
0.310
|
13
|
4.85%
|
0.587
|
49,642
|
5.81%
|
Readmission
|
152
|
9.46%
|
<0.001
|
123
|
9.19%
|
<0.001
|
29
|
10.82%
|
<0.001
|
48,961
|
5.73%
|
LOS
|
2.80
|
|
<0.001
|
2.77
|
|
<0.001
|
4.60
|
|
<0.001
|
2.39
|
|
Abbreviations: DVT, deep vein thrombosis; LOS, length of stay; SSI, surgical site
infection; UTI, urinary tract infection.
Note: Groups were analyzed with chi-squared analysis compared with control group.
Statistically significant p-Values (p < 0.05) are indicated in bold.
a Per HIPAA requirements, <11 cohort sizes are not reportable.
On multivariable analysis, AHIV patients were found to have lower odds of anemia (OR:
0.697; 95% CI: 0.587–0.821; p < 0.001) compared with the control cohort while AIDS patients were found to have
greater odds of anemia (OR: 1.516; 95% CI: 1.123–2.018; p = 0.005) relative to the control group. Additionally, AIDS patients were found to
have greater odds of renal failure (OR: 2.129; 95% CI: 1.239–3.451; p = 0.004) within 90 days of TKA compared with the control group.
Discussion
It is imperative to understand the relationship between HIV/AIDS and postoperative
complications following TKA given the increased life expectancy and rising incidence
of TKA in this population. This study aimed to determine the 90-day complication rates
and 2-year postoperative surgical complications in patients with a diagnosis of HIV
who underwent TKA for OA. To our knowledge, no prior study has utilized a large administrative
database to study the outcomes of HIV-positive patients who underwent OA-indicated
TKA.
Patients with a diagnosis of HIV, both symptomatic and asymptomatic, had significantly
increased odds of certain complications, including arrhythmia without atrial fibrillation
and decreased odds of other complications, such as anemia, following TKA. However,
patients with a diagnosis of AIDS had significantly increased odds of several 90-day
postoperative complications including renal failure, anemia, and pneumonia (p = 0.004, p = 0.005, and p = 0.003, respectively). We were surprised to find that there were no significant
differences in 2-year postoperative surgical complications between HIV-positive and
HIV-negative TKA patients after multivariable regression analysis was performed ([Table 3]).
With the advent of HAARTs, HIV-positive patients are making significant improvements
in survivorship,[17] which is expected to result in increased demand for total joint arthroplasties (TJAs)
among HIV-positive patients.[18] There is currently no consensus in the literature regarding perioperative complications
in HIV-positive patients undergoing TKA. Some studies report that HIV-positive patients
are not at a significantly increased risk compared with the general population.[7]
[10]
[11] Other studies report that HIV-positive patients may be at a significantly increased
risk for postoperative complications compared with their HIV-negative cohort.[4]
[5] O'Neill et al conducted a systematic review of 19 studies with a subgroup analysis
of 4 studies.[9] The authors found that HIV-positive patients were at a significantly increased risk
of infection and revision (risk ratio of 3.31 and 2.25, respectively). However, the
authors caution that the quality of evidence was low and that there was heterogeneity
between the studies. Parvizi et al report a significantly increased rate of early
procedural failures among a cohort of HIV-positive patients undergoing TJA (13 knee
procedures and 8 hip procedures).[4] Of the 21 total procedures, 12 were not successful due to loosening (average time
of 9.5 years) and early repeat surgeries due to a decreased range of motion, hematoma
of the knee, and other reasons. Six of the 12 procedural failures were due to infections,
which had an average time to revision of 3.5 years. This study was limited due to
its retrospective nature and small sample size. Olson et al conducted a multicenter
retrospective cohort analysis of 110 HIV-positive patients and 240 control patients
who underwent TJAs (85 total hip arthroplasties [THAs] and 25 TKAs).[19] The authors found a statistically significantly increased risk for venous thromboembolism
in the HIV-positive TKA group compared with the control group (8.0 vs. 1.7% ; p = 0.046). Accordingly, they recommended that stronger prophylactic anticoagulation
and a longer duration of prophylaxis be considered for HIV-positive patients undergoing
TKA.
Boylan et al conducted a nationwide retrospective review and found that HIV-positive
individuals undergoing TKA did not have significantly higher surgical complications
overall compared with controls, but they were found to be at a significantly higher
risk for developing infections.[20] Falakassa et al conducted a retrospective cohort analysis of 24 HIV-positive patients
(31 THAs and one TKA).[7] In this study, there was one instance of aseptic loosening but no PJIs. The authors
concluded that HIV-positive status did not place patients at an increased risk for
postoperative PJIs and that patients with CD4 counts >200 on HAART therapy were at
a similar risk to HIV-negative individuals.[7] Capogna et al reported no significant differences in infection, survivorship, or
revision after TJA comparing 69 HIV-positive patients to 138 controls.[21]
Lin et al analyzed the Nationwide Inpatient Sample and identified 5,681,024 patients
who were admitted for THAs and TKAs (0.14% were HIV-positive).[10] The authors found no significant increase in total complications between the HIV-positive
and control group for TKA patients. While there were some increased complications
(acute renal failure, wound infection, and increased indication for postoperative
debridement and irrigation) identified in THA patients, it could not be concluded
that HIV-positive status alone was a risk factor for increased complications after
TJA. Roof et al conducted a multicenter retrospective study that analyzed discrepancies
between 25 HIV-negative and 25 HIV-positive patients who underwent TKA.[8] The authors found that HIV-positive patients had an acceptable complication risk
compared with HIV-negative patients (not statistically significant); however, HIV-positive
patients who underwent TKA had significantly increased length of stay (3.8 vs. 2.28
days, p = 0.004).
While some 90-day complications were more prevalent in our HIV-positive cohort, there
were no significant increases in 2-year postoperative surgical complications on multivariable
linear regression analysis. Similar findings were seen in the study by Issa et al
where no significant postoperative complications were seen with HIV-positive individuals
who underwent TKA.[11] Knee implant survivorship between the HIV-positive and control groups was also comparable
with no significant differences.
The significant heterogeneity in the literature indicates that HIV-positive status
should not necessarily prevent patients from receiving TKAs. If proper preoperative
and perioperative precautions are taken (use of antibiotics, anticoagulants, etc.),
then HIV-positive patients may be successful TKA candidates. However, it is imperative
that surgeons carefully weigh the risks and benefits of operating since some studies
do report increased complications and infection risks for HIV-positive patients. Surgeons
must assess each patient's individual risk factors, including comorbidities and past
medical/surgical history, before deciding to move forward with TKA.
There are numerous strengths to this study. This study is unique in that it analyzes
the 2-year postoperative surgical complications of patients with and without a diagnosis
of HIV who underwent TKA for OA of the knee. The additional analysis comparing AHIV
and AIDS is also novel. Study power was facilitated by using a large nationwide database,
allowing the results to be more generalizable due to its inclusion of patient data
from numerous institutions. However, the authors also recognize the limitations of
this study. As with any retrospective database study, coding errors might have affected
the results. Furthermore, we did not have access to the CD4 count or antiretroviral
regimen each patient was taking, which may have influenced how the cohorts were identified.
Further, revisions or other complications outside the 2-year study window were not
captured. As such, it is likely that our study underestimates revision rates, and
longer term studies are needed to better define the longitudinal risks of TKA in HIV-positive
patients to guide patient counseling and shared decision-making.
Conclusion
After multivariable analysis, we found that patients with a diagnosis of HIV or AIDS
are not at increased risk for developing surgical complications within 2 years of
undergoing TKA. We recommend patient optimization focusing on the overall comorbidities
rather than the patient's HIV status when considering TKA in HIV-positive patients.