Abstract
Objective:
This study aimed to determine whether age affects thromboelastography (TEG) coagulation profiles among elderly patients with peripheral arterial disease (PAD). We hypothesized that TEG parameters would not significantly differ between age groups when controlled for anticoagulation regimen.
Methods:
This was a prospective, single-institution, observational study that included patients aged 65 years and older who underwent open or endovascular lower extremity revascularization for PAD from December 2020 through December 2023. 158 patients were grouped into categories: age 65-74 and age 75+ and anticoagulation regimen (single antiplatelet [50%], dual antiplatelet [15%], therapeutic anticoagulation [27%], none [8%]). Objective TEG coagulation profiles were collected preoperatively and were compared among patient groups. One-way ANOVA analysis was used to compare three or more groups of continuous data, and chi-squared analysis or Fisher’s exact test were used to compare categorical data.
Results:
Among 158 patients (36.4% female, median age 74.5±6.6 years), there were no significant differences in TEG parameters (reaction time, maximum amplitude, lysis at 30 minutes, angle, ADP% aggregation, ADP% inhibition) between age groups when stratified by anticoagulation regimen (all p>0.05). Thrombosis rates were similar between age groups (21.1% vs. 20.6%, p=0.936), but mortality was significantly higher in the 75+ group (20.6% vs. 5.6%, p=0.005).
Conclusions:
Objective coagulation parameters do not appear to vary significantly among age groups within the elderly population when controlled for antiplatelet/anticoagulant regimen. TEG profiles may be used to guide anticoagulation management among elderly patients. Further studies can help elucidate the full utility of TEG profiles for coagulation surveillance among elderly patients.
Keywords: Thromboelastography, Peripheral Arterial Disease, Anticoagulants, Thrombosis, Aged
Table of contents summary:
In this prospective study of 158 elderly patients with peripheral arterial disease, thromboelastography parameters showed no significant differences between age groups when controlled for blood-thinning medications. These findings suggest TEG results can be interpreted similarly across elderly age groups without age-specific adjustments.
Introduction
Peripheral arterial disease (PAD) affects millions worldwide, with prevalence increasing dramatically among the elderly population.1–5 The disease carries significant morbidity and mortality risks, with nearly 50% of patients requiring amputation dying within one year of the procedure.6–7 While both endovascular and open surgical revascularization options exist, optimal post-intervention management remains controversial.
Surveillance of PAD patients is therefore critical to avoid complications, including graft thrombosis or amputation, though no standardized method of surveillance has been agreed upon.2,4,7 Anticoagulant medications such as rivaroxaban and antiplatelet medications such as aspirin are often used among this patient population to decrease the risk of progression of PAD according to the standard of care8,9. However, there is no standardized method at this time for deciding which patients benefit from these medications. This gap is particularly concerning in elderly patients, who may have altered coagulation profiles and increased bleeding risks. Aging induces significant changes in hemostasis, generally shifting toward a more procoagulant state. A recent study showed progressive increases in multiple procoagulant factors with age, including elevated levels of fibrinogen (increasing approximately 0.1 g/L per decade), Factor VIII (reaching mean levels over 200 U/dL in the seventh decade), and other coagulation factors such as Factor V, VII, and IX. Additionally, they noted increased von Willebrand factor (VWF) levels and enhanced platelet activation with aging.10 These findings are further supported by thrombelastography (TEG) study which demonstrated that both aging and female gender were associated with increased coagulability.11 One aspect of surveillance among patients with PAD is monitoring their coagulation profiles, and one way to accomplish this is by using thromboelastography (TEG). TEG is a viscoelastic assay that provides a real-time coagulation profile for individual patients. It evaluates five parameters: Reactive time (R), K-time (K), alpha angle, maximum amplitude (MA) and percent lysis 30 minutes after MA (LY30). It has emerged as a promising tool for real-time coagulation monitoring, providing comprehensive assessment of clot formation, strength, and lysis. However, TEG is still a relatively new in the field of vascular surgery, and TEG values among elderly patients have not been fully described.1 12–14
Most studies examining the impact of antiplatelet and direct oral anticoagulant (DOAC) therapies on TEG have focused on cardiovascular disease, cerebrovascular disease, and trauma.15–17 Antiplatelet therapy primarily influences TEG parameters associated with platelet function, such as MA, often reducing clot strength depending on the specific agent used.16 In contrast, anticoagulants, particularly DOACs, prolong R-time by inhibiting thrombin generation.17 While TEG demonstrates broad clinical applicability, there is limited data on its use in elderly patients with PAD. Further research is needed to explore its potential in this population.
This study aimed to assess whether age impacts TEG coagulation profiles among elderly patients with PAD, with the goal of optimizing post-intervention anticoagulation management in this vulnerable population.
Methods
Study Design and Inclusion Criteria:
This study is a prospective, single-institution, observational review of patients undergoing open or endovascular lower extremity revascularization for peripheral arterial disease at a large tertiary care institute from December 2020 through December 2023. Institutional Review Board approval was obtained prior to beginning data collection (Protocol # 2022P001918). Only patients who were 65 years of age or older at the time of their surgery were included in the analysis. Daily operating room schedules were reviewed for planned open or endovascular lower extremity revascularization procedures including balloon angioplasty, drug eluting balloon, balloon expanding stent, self-expandable stent, endarterectomy, bypass or deep venous arterialization, in the setting of peripheral artery disease. Patients underwent revascularization following clinical assessment by a board-certified vascular surgeon. Patients with claudication underwent intervention if their symptoms were lifestyle-limiting and/or they failed a supervised walking program. Patients with chronic limb-threatening ischemia (CLTI) were treated if they exhibited evidence of line flow. Patients who met the study criteria were approached by research personnel and provided information about the research study. Patients who agreed to provide written consent were enrolled in the study. Patients who did not undergo a successful revascularization procedure, they were considered screen fails and were excluded from the study. Additionally, patients were excluded if they failed or declined to written informed consent, were under 60 years of age, weighed less than 50 kg in bodyweight, if age was unknown and had contraindications to anticoagulation and/or antiplatelet therapy.
TEG analysis
A blood sample was collected from each patient on the day of their index surgical procedure prior to being taken to the operating room (baseline) as well as at 1 to 5-day, 1 month, 3 month and 6 months postoperative For the purpose of this specific study, only baseline samples were analyzed. Approximately 8 mL of blood was collected per patient and placed into both citrated and heparinized vacutainer tubes. The blood was then run through a thromboelastography machine (TEG®6S Haemonstasis Analyzer [Haemonetics Corp., 149 Boston MA]), which processed the blood samples and then provided standard thromboelastography values. The analyzer tracks the harmonic motion of a blood drop during clotting, measuring changes in elasticity and resonant frequency.18 TEG measures multiple components of the dynamic pathway of clot formation within the sample of blood: it measures the duration of time it takes for a clot to begin to form (reaction time, R), the amount of time needed for the clot to form (K value), the rate at which fibrin crosslinking occurs (alpha angle), the strength of the clot that forms (maximum amplitude, MA), and the amount of clot that breaks down over a period of 30 minutes (lysis 30, LY30).14, 19, 20 (Figure 1) Additionally, % inhibition reflects the reduction in platelet contribution to overall clot strength, while % aggregation represents the proportion of platelets that remain uninhibited.18
Figure 1.
Thromboelastography (TEG) parameters are categorized into two phases: coagulation, which includes clot initiation and kinetics, and fibrinolysis, which encompasses clot stability and breakdown. Reaction time (R) indicates clot initiation (orange); K-time (K) and α-angle represent clot kinetics (blue); maximum amplitude (MA) measures the clot strength; and percent lysis at 30 minutes (Ly30) represents fibrinolysis activity (green).
Patient data and grouping:
Demographic data was obtained using our institution’s electronic medical record. Demographic variables that were analyzed included age, sex, body mass index (BMI), past or current tobacco use, diabetes, hypertension, hyperlipidemia, coronary artery disease, history of myocardial infarction, history of venous thromboembolism, and Rutherford score for chronic limb ischemia at the time of presentation. Any antiplatelet and anticoagulant medications that the patients were taking at the time of presentation was also recorded. Significant bleeding was defined as bleeding requiring 2 or more units of blood transfusion, and/ or bleeding requiring surgical reintervention. Patients were grouped into two categories: age 65-74, and age 75+; they were then further grouped by antiplatelet/anticoagulant regimen to control for effects of these medications on the analysis (single antiplatelet [AP] therapy (aspirin or clopidogrel), dual AP therapy (aspirin + clopidogrel or aspirin + ticagrelor), and therapeutic anticoagulation [AC] (heparin, apixaban, rivaroxaban, warfarin, enoxaparin). Among patients not on antiplatelet or anticoagulation therapy (n=13), some were urgent/emergent revascularizations, had temporary medication discontinuation for medical reasons or were non-compliant with prescribed therapy. Objective TEG coagulation profiles were collected preoperatively and were compared among these patient groups. Patients who developed thrombosis were classified as having an acute event if it occurred within 30 days of the procedure and as a late event if it occurred after 30 days.
Statistical Analysis:
Statistical analysis was conducted to compare demographic variables between patient age groups and to compare thromboelastography values when stratified by patient age and anticoagulation/antiplatelet regimen. Descriptive statistics were calculated for all variables. Continuous variables were reported as means with standard deviations. Categorical variables were presented as frequencies and percentages. One-way ANOVA analysis was used to compare three or more groups of continuous data, and chi-squared analysis or Fisher’s exact test were used to compare categorical data. P-values of <0.05 were considered to be statistically significant.
Results:
A total of 302 patients were enrolled in the study, of whom 158 were included in the final analysis. Screen failures occurred in 64 (21.2%) patients due to unsuccessful revascularization, while 81 (26.8%) patients were excluded for being under 65 years of age. Among the overall cohort, 58 (36.4%) were female and the overall cohort median follow-up period was 2.62months (IQR 0.26 −5.84). Demographic data collected for all patients in the study showed a mean age of 74.5 years; 88 patients (55.6%) were diabetic, 143 patients (90.5%) had a history of hypertension, and 140 patients (88.6%) had a history of hyperlipidemia. A list of demographic data for the full study cohort is shown in Table I.
Table I.
Baseline Demographics for Study Cohort
| Study cohort(N=158) | |
|---|---|
|
| |
| Age (years), mean ± SD | 74.5 ± 6.6 |
|
| |
| Female sex, n (%) | 58 (36) |
|
| |
| BMI mean ± SD | 26.5 ± 4.8 |
|
| |
| Tobacco Use, n (%) | |
| Never Smoker | 32 (20) |
| Prior smoker, quit >10 years ago | 72 (46) |
| Prior smoker, quit 1-10 years ago | 29 (18) |
| Current smoker within past year | 25 (16) |
|
| |
| Diabetes, n (%) | |
| Nondiabetic | 70 (44) |
| Type 1 Diabetic | 2 (1) |
| Type 2 Diabetic | 86 (54) |
|
| |
| Hypertension, n (%) | 143 (91) |
|
| |
| Hyperlipidemia, n (%) | 140 (89) |
|
| |
| Coronary Artery Disease, n (%) | 87 (55) |
| Myocardial Infarction, n (%) | 44 (28) |
|
| |
| Venous Thromboembolism | 28 (18) |
|
| |
| Rutherford Score PAD, n (%) | |
| 1 | 4 (3) |
| 2 | 15 (11) |
| 3 | 34 (24) |
| 4 | 24 (17) |
| 5 | 47 (33) |
| 6 | 17 (12) |
|
| |
| AP/AC Regimen, n (%) | |
| No AP/AC | 13 (8) |
| Single AP | 79 (50) |
| Dual AP | 24 (15) |
| Therapeutic AC ± AP | 43 (27) |
|
| |
| Time to follow up (months), median (IQR) | 2.62 (0.26 −5.84) |
|
| |
| Time to thrombosis (months, median (IQR) | 2.86 (1.08 - 4.7) |
AP = antiplatelet (aspirin or clopidogrel)
AC = anticoagulant (heparin, apixaban, rivaroxaban, warfarin, enoxaparin)
PAD= peripheral artery disease
The patients’ antiplatelet and anticoagulant regimens were also documented: 79 patients (49.6%) were on a single antiplatelet medication without anticoagulation, 24 patients (15.0%) were on dual antiplatelet therapy without anticoagulation, 43 patients (27.0%) were on anticoagulation medication (with or without antiplatelet medication), and 13 patients (8.1%) were not taking any antiplatelet or anticoagulant medication (Table I).
The patients were then categorized into two age groups: age 65-74 (n=90) and age 75+ (n=68). When comparing demographic data between these two groups, there was a statistically significant difference in body mass index (BMI), which was higher in the younger age group compared to the older age group (27.2 ± 5.2 versus 25.6 ± 3.9 respectively, p=0.033). There were no other statistically significant differences found between groups when analyzing the other demographic variables, including the rate of hypertension, hyperlipidemia, coronary artery disease, or history of myocardial infarction. A list of demographic data that is subdivided by patient age category is shown in Table II.
Table II.
Baseline Demographics for Study Cohort, Subdivided by Age
| Age 65-74 (N=90) |
Age 75+ (N=68) |
p-value | |
|---|---|---|---|
|
| |||
| Female sex, n (%) | 28 (31) | 30 (44) | 0.099 |
|
| |||
| BMI, mean ± SD | 27.2 ± 5.2 | 25.6 ± 3.9 | 0.033 * |
|
| |||
| Tobacco Use, n (%) | 0.384 | ||
| Never Smoker | 17 (19) | 15 (22) | |
| Prior smoker, quit >10 years ago | 38 (42) | 34 (50) | |
| Prior smoker, quit 1-10 years ago | 17 (19) | 12 (18) | |
| Current smoker within past year | 18 (20) | 7 (10) | |
|
| |||
| Diabetic, n (%) | 56 (62) | 32 (47) | 0.075 |
|
| |||
| Hypertension, n (%) | 81 (90) | 62 (91) | 1.000 |
|
| |||
| Hyperlipidemia, n (%) | 82 (91) | 58 (85) | 0.314 |
|
| |||
| Coronary Artery Disease, n (%) | 49 (54) | 38 (56) | 0.873 |
| Myocardial Infarction, n (%) | 27 (30) | 17 (25) | 0.591 |
|
| |||
| Venous Thromboembolism, n (%) | 18 (20) | 12 (18) | 0.838 |
|
| |||
| Rutherford Score for chronic ischemia, n (%) | 0.993 | ||
| 1-2 | 11 (12) | 8 (12) | |
| 3-4 | 33 (37) | 25 (37) | |
| 5-6 | 37 (41) | 27 (40) | |
|
| |||
| AP/AC Regimen, n (%) | 0.784 | ||
| No AP/AC | 5 (6) | 4 (6) | |
| Single AP | 48 (54) | 31 (47) | |
| Dual AP | 14 (16) | 10 (15) | |
| Therapeutic AC ± AP | 22 (25) | 21 (32) | |
Denotes statistical significance
AP = antiplatelet (aspirin or clopidogrel)
AC = anticoagulant (heparin, apixaban, rivaroxaban, warfarin, enoxaparin)
Patients were then stratified by both age as well as antiplatelet/anticoagulant regimen (Table III). The medication categories that were used were single antiplatelet medication without anticoagulation (n=79), dual antiplatelet therapy without anticoagulation (n=24), and anticoagulation medication with or without antiplatelet medication (n=43). Patients who were not taking any antiplatelet or anticoagulant medication were not included in this portion of the analysis due to the low number of patients in this category (n=13). When stratified in this way, there were no statistically significant differences among objectively assessed TEG coagulation parameters, including the variables reaction time (R), maximum amplitude (MA), lysis at 30 minutes (LY30), angle, ADP % aggregation, and ADP % inhibition. These comparisons and their associated P-values are delineated in Table III.
Table III.
Thromboelastography values in elderly patients with peripheral arterial disease, stratified by age and antiplatelet/anticoagulation regimen.
| Single AP Therapy |
Age 65-74
(N=48) |
Age 75+
(N=31) |
p-value a | |
| R (mins), mean ± SD | 6.1 ± 2.2 | 6.2 ± 2.2 | 0.794 | |
| LY30 (%), mean ± SD | 0.9 ± 1.6 | 0.3 ± 0.4 | 0.091 | |
| ADP MA (mm), mean ± SD | 52.0 ± 16.4 | 51.3 ± 14.6 | 0.861 | |
| ADP % aggregation, mean ± SD | 82.7 ± 20.5 | 87.7 ± 17.4 | 0.393 | |
| ADP % inhibition, mean ± SD | 17.3 ± 20.5 | 12.3 ± 17.4 | 0.393 | |
| CK angle (degree), mean ± SD | 70.6 ± 10.9 | 71.1 ± 7.4 | 0.832 | |
| Dual AP Therapy |
Age 65-74
(n=14) |
Age 75+
(n=10) |
p-value | |
| R (mins), mean ± SD | 6.0 ± 1.6 | 6.6 ± 2.0 | 0.610 | |
| LY30 (%), mean ± SD | 0.2 ± 0.4 | 0.6 ± 1.4 | 0.268 | |
| ADP MA (mm), mean ± SD | 45.8 ± 17.9 | 41.2 ± 20.1 | 0.570 | |
| ADP % aggregation, mean ± SD | 69.1 ± 27.2 | 57.4. ± 34.3 | 0.459 | |
| ADP % inhibition, mean ± SD | 27.9 ± 28.7 | 42.6 ± 34.3 | 0.367 | |
| CK angle (degree), mean ± SD | 69.9 ± 10.4 | 65.7 ± 16.5 | 0.488 | |
| Therapeutic AC |
Age 65-74
(N=22) |
Age 75+
(N=21) |
p-value | |
| R (mins), mean ± SD | 7.4 ± 2.6 | 6.2 ± 2.6 | 0.142 | |
| LY30 (%), mean ± SD | 0.6 ± 1.2 | 0.6 ± 0.7 | 0.677 | |
| ADP MA (mm), mean ± SD | 45.5 ± 18.8 | 50.0 ± 14.0 | 0.396 | |
| ADP % aggregation, mean ± SD | 69.6 ± 31.5 | 83.2 ± 15.9 | 0.144 | |
| ADP % inhibition, mean ± SD | 30.4 ± 31.5 | 16.8 ± 15.9 | 0.144 | |
| CK angle (degree) , mean ± SD | 69.0 ± 10.7 | 71.5 ± 10.2 | 0.461 | |
Patients who were not on any AC/AP were not included in the above chart due to insufficient numbers.
AP = antiplatelet (aspirin or clopidogrel)
AC = anticoagulation (heparin, apixaban, rivaroxaban, warfarin, enoxaparin)
R = reaction time
LY30 = Lysis at 30 minutes
MA = maximum amplitude
CK = Citrated Kaolin
Statistics by Pearson’s Chi-squared
Patients on single antiplatelet therapy showed a similar clot strength (indicated by the maximum amplitude, MA) regardless of age category (MA of 52.0 ± 16.4 for age 65-74 versus 51.3 ± 14.6 for age 75+, p= 0.86). Patients on dual antiplatelet therapy likewise showed a similar clot strength regardless of age category (MA of 45.8 ± 17.9 for age 65-74 versus 41.2 ± 20.1 for age 75+, p= 0.57). Among patients on therapeutic anticoagulation, there again was no significant difference in clot strength between the different age categories (MA of 45.5 ± 18.8 for age 65-74 versus 50.0 ± 14.0 for age 75+, p= 0.39).
Among patients on anticoagulation, the reaction time R was not statistically significantly different by age group, though it did show a slightly longer time to clot in the younger age group (R of 7.4 ± 2.6 for age 65-74 versus 6.2 ± 2.6 for age 75+, p= 0.14).
Thrombosis of the area of initial intervention occurred in 19 patients (21.1%) in the 65-74 age group, compared to 14 patients (20.6%) in the 75+ age group (p=0.936). In both groups, the majority of patients experienced late thrombosis (73.7% in the 65–74 age group vs. 85.7% in the 75+ age group). Although the 75+ age group demonstrated a higher incidence of late thrombosis and the 65–74 age group showed a higher incidence of acute thrombosis, the difference was not statistically significant (p = 0.69). The overall cohort median time to thrombosis was 2.86 months (IQR 1.08 - 4.7). Significant bleeding events during follow-up occurred in 3 patients (3.3%) in the 65-74 age group, compared to 1 patient (1.5%) in the 75+ age group (p=0.634). Death occurred in 5 patients (5.6%) in the 65-74 age group, compared to 14 patients (20.6%) in the 75+ age group, which was statistically significant with p=0.005.
Discussion:
PAD impacts millions of people around the world, and is particularly prevalent among the elderly population.1–5 PAD is associated with certain modifiable risk factors such as diabetes, tobacco use, and obesity, but the risk also increases with age itself.1–5 It is well-established that patients with PAD should receive routine surveillance after undergoing lower extremity surgical revascularization. However, there is no standardized protocol for PAD surveillance at this time. One possible method that has been proposed for monitoring patients’ propensity for thrombosis is thromboelastography (TEG), which is a viscoelastic assay that allows for creation of real-time individualized coagulation profiles by running a small sample of blood through a thromboelastography machine (TEG®6S Haemonstasis Analyzer [Haemonetics Corp., 149 Boston MA]). If there is an abnormality, the changes in the TEG parameters can help to indicate what the abnormality might be, and if there could be a particular deficiency within the blood sample. TEG is therefore a very useful tool, and it is growing in popularity in the vascular surgical field. However, it still remains a relatively new tool, and there is room for further study of its intricacies and possible drawbacks.
In this study, our objective was to determine whether TEG profiles were impacted by age among elderly patients with peripheral arterial disease. To determine this, we compared TEG profiles of patients undergoing lower extremity revascularization and grouped patients according to their age at the time of their surgery. We then subcategorized patients based on their antiplatelet/anticoagulation regimen, to remove this as a possible confounding factor in our analysis. When patients were stratified by age and controlled for their antiplatelet/anticoagulant regimen, there were no statistically significant differences among objectively assessed TEG coagulation parameters, including the following variables: reaction time (R), maximum amplitude (MA), lysis at 30 minutes (LY30), angle, ADP % aggregation, and ADP % inhibition. This suggests that differences in age among the elderly population do not correspond with changes in common parameters within thromboelastography coagulation profiles. This is important to consider when using TEG profiles to guide anticoagulation management among elderly patients with peripheral arterial disease.
TEG is a promising tool for monitoring the clotting profile of individual patients, and the knowledge that TEG values should not need to be adjusted for age among the elderly population is useful when interpreting these values. With time, TEG may continue to become more prominent in the field of vascular surgery as a method of creating real-time individualized coagulation profiles, and the more that can be determined about the intricacies of TEG, the more confident physicians can be in using its values to help guide management of patients.
Several recent studies have analyzed the use of thromboelastography within the field of vascular surgery. Majumdar et al demonstrated that a cut point of >70.8% platelet aggregation and <29.2% platelet inhibition were associated with increased risk of thrombotic events.13 These variables of platelet aggregation and inhibition were included in our study as well, as represented by ADP aggregation and ADP inhibition in the above discussion. When assessing the entire patient cohort in this study, the average ADP % aggregation was 78.7 and the average ADP % inhibition was 21.0. Both these values are past the cut points given in Majumdar et al, indicating an increased risk of thrombosis. This same pattern is also seen when dividing our study cohort into their age categories: the 65-74 age group had an average ADP % aggregation of 77.4 and average ADP % inhibition of 22.2. The 75+ age group had an average ADP % aggregation of 80.4 and average ADP % inhibition of 19.6%. These values are past the cut points listed in the study by Majumdar et al, indicating increased risk of thrombosis. Given these findings, it could be postulated that the patients in our cohort may not have been on adequate antiplatelet medication at the time of initial revascularization. The abnormal TEG values observed in patients not on anticoagulation likely reflect the underlying prothrombotic state associated with peripheral arterial disease, as TEG can detect alterations in clot formation, strength, and breakdown even in the absence of anticoagulant medications. Further studies are currently underway to determine if these baseline thromboelastography values can be improved through tailored individualized antiplatelet therapy. Given the significantly higher mortality rate in our 75+ age group and the known risks of anticoagulation in elderly patients, more frequent TEG-based monitoring may be warranted in this population. This could allow for dynamic medication adjustments to balance thrombosis prevention with bleeding risk.
A primary limitation of this study was the relatively small sample size, given that not every patient who underwent lower extremity revascularization at our institution could be captured. This was particularly true in certain situations where research consent could not be obtained prior to the procedure, such as a case that was booked urgently or emergently, or if a case was occurring on a weekend or holiday when adequate research personnel were not available. This could therefore contribute to a skewed enrollment as patients who required urgent or emergent interventions often could not be included in the study. While TEG with platelet mapping provided information about platelet function, we did not perform P2Y12 testing, which could have offered additional insights about clopidogrel response. Another key limitation is that we only collected TEG measurements preoperatively, without longitudinal follow-up data. We are currently conducting a follow-up study visits examining serial TEG measurements at 1-5 day, 1-, 3-, and 6-months post-intervention to address these important questions and evaluate the utility of TEG-guided medication adjustment. The low number of bleeding events in our cohort limited our ability to identify specific risk factors for bleeding complications. Future studies with larger sample sizes are needed to better characterize bleeding risk factors in this population, to analyze the intricacies of thromboelastography and guide its use in the field of vascular surgery.
Conclusions:
Our study shows that age does not independently affect TEG coagulation parameters among elderly PAD patients when controlling for anticoagulation regimen. These findings suggest TEG can be used consistently across elderly age groups for anticoagulation monitoring, though higher mortality in older patients warrants careful clinical surveillance. Further studies can help elucidate the full utility of TEG profiles for coagulation surveillance among elderly patients, as well as among patients of all ages.
Article highlights:
Type of Research:
Single-center prospective cohort study
Key Findings:
In 158 elderly patients (≥65 years) with peripheral arterial disease undergoing lower extremity revascularization, thromboelastography (TEG) coagulation parameters showed no significant differences between age groups (65-74 vs 75+ years) when controlled for antiplatelet/anticoagulation regimen. Death occurred in 5.6% of age 65-74 group versus 20.6% in age 75+ group (p=0.005).
Take Home Message:
Thromboelastography (TEG) blood clotting test results are similar across different elderly age groups, making it a reliable tool for monitoring blood thinning medications in elderly patients with peripheral arterial disease.
Funding:
This work was supported by the National Institute of Health [R21 Federal Grant R21 AG077310]
Footnotes
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Declaration of conflicts of interest: The authors declare that there is no conflict of interest.
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