Publications by Year: 2023

IMPORTANCE: The optimal pharmacologic thromboprophylaxis agent after total hip and total knee arthroplasty is uncertain and consensus is lacking. Quantifying the risk of postoperative venous thromboembolism (VTE) and bleeding and evaluating comparative effectiveness and safety of the thromboprophylaxis strategies can inform care.

OBJECTIVE: To quantify risk factors for postoperative VTE and bleeding and compare patient outcomes among pharmacological thromboprophylaxis agents used after total hip and knee arthroplasty.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study used data from a large health care claims database. Participants included patients in the United States with hip or knee arthroplasty and continuous insurance enrollment 3 months prior to and following their surgical procedure. Patients were excluded if they received anticoagulation before surgery, received no postsurgical pharmacological thromboprophylaxis, or had multiple postsurgery thromboprophylactic agents. In a propensity-matched analysis, patients receiving a direct oral anticoagulant (DOAC) were matched with those receiving aspirin.

EXPOSURES: Aspirin, apixaban, rivaroxaban, enoxaparin, or warfarin.

MAIN OUTCOMES AND MEASURES: The primary outcome was 30-day cumulative incidence of postdischarge VTE. Other outcomes included postdischarge bleeding.

RESULTS: Among 29 264 patients included in the final cohort, 17 040 (58.2%) were female, 27 897 (95.2%) had inpatient admissions with median (IQR) length of stay of 2 (1-2) days, 10 948 (37.4%) underwent total hip arthroplasty, 18 316 (62.6%) underwent total knee arthroplasty; and median (IQR) age was 59 (55-63) years. At 30 days, cumulative incidence of VTE was 1.19% (95% CI, 1.06%-1.32%) and cumulative incidence of bleeding was 3.43% (95% CI, 3.22%-3.64%). In the multivariate analysis, leading risk factors associated with increased VTE risk included prior VTE history (odds ratio [OR], 5.94 [95% CI, 4.29-8.24]), a hereditary hypercoagulable state (OR, 2.64 [95% CI, 1.32-5.28]), knee arthroplasty (OR, 1.65 [95% CI, 1.29-2.10]), and male sex (OR, 1.34 [95% CI, 1.08-1.67]). In a propensity-matched cohort of 7844 DOAC-aspirin pairs, there was no significant difference in the risk of VTE in the first 30 days after the surgical procedure (OR, 1.14 [95% CI, 0.82-1.59]), but postoperative bleeding was more frequent in patients receiving DOACs (OR, 1.36 [95% CI, 1.13-1.62]).

CONCLUSIONS AND RELEVANCE: In this cohort study of patients who underwent total hip or total knee arthroplasty, underlying patient risk factors, but not choice of aspirin or DOAC, were associated with postsurgical VTE. Postoperative bleeding rates were lower in patients prescribed aspirin. These results suggest that thromboprophylaxis strategies should be patient-centric and tailored to individual risk of thrombosis and bleeding.

BACKGROUND: Days at home (DAH) represents an important patient-oriented outcome that quantifies time spent at home after a medical event; however, this outcome has not been fully evaluated for low-surgical-risk patients undergoing transcatheter aortic valve replacement (TAVR). We sought to compare 1- and 2-year DAH (DAH365 and DAH730) among low-risk patients participating in a randomized trial of TAVR with a self-expanding bioprosthesis versus surgical aortic valve replacement (SAVR).

METHODS: Using Medicare-linked data from the Evolut Low Risk trial, we identified 619 patients: 606 (322 TAVR/284 SAVR) and 593 (312 TAVR/281 SAVR) were analyzed at 1 and 2 years, respectively. DAH was calculated as days alive and spent outside a hospital, inpatient rehabilitation, skilled nursing facility, long-term acute care hospital, emergency department, or observation stay. Mean DAH was compared using the t test.

RESULTS: The mean (SD) age and female sex were 74.7 (5.1) and 74.3 (4.9) years and 34.6% (115/332) and 30.3% (87/287) in TAVR and SAVR, respectively. Postprocedural discharge to rehabilitation occurred in ≤3.0% (≤10/332) in TAVR and 4.5% (13/287) in SAVR. The mean DAH365 was comparable in TAVR versus SAVR (352.2±45.4 versus 347.8±39.0; difference in days, 4.5 [95% CI, 2.3-11.2]; P=0.20). DAH730 was also comparable in TAVR versus SAVR (701.6±106.0 versus 699.6±94.5; difference in days, 2.0 [-14.1 to 18.2]; P=0.81). Secondary outcomes DAH30 and DAH90 were higher in TAVR (DAH30, 26.0±3.6 versus 20.7±6.4; difference in days, 5.3 [4.5-6.2]; P<0.001; DAH90, 85.1±8.3 versus 78.7±13.6; difference in days, 6.4 [4.6-8.2]; P<0.001).

CONCLUSIONS: In the Evolut Low Risk trial linked to Medicare, low-risk patients undergoing TAVR spend a similar number of days at home at 1 and 2 years compared with SAVR. Days spent at home at 30 and 90 days were higher in TAVR. In contrast to higher-risk patients studied in prior work, there is no clear advantage of TAVR versus SAVR for DAH in the first 2 years after AVR in low-surgical-risk patients.

Whether thrombocytopenia substantively increases the risk of hemorrhage associated with anticoagulation in patients with atrial fibrillation (AF) is not established. The purpose of this study was to compare rates of bleeding in patients with AF and thrombocytopenia (platelet count < 100 000/μL) to patients with AF and normal platelet counts (>150 000/μL). We performed a propensity score-matched, retrospective cohort study of adults (n = 1070) with a new diagnosis of AF who received a prescription for an oral anticoagulant between 2015 and 2020. The thrombocytopenia cohort was defined as having at least 2 platelet counts <100 000/μL on separate days in the period spanning the 12 weeks preceding the initiation of anticoagulation to 6 weeks after the initiation of anticoagulation. The primary end point was the 1-year cumulative incidence of major bleeding; secondary end points included clinically relevant bleeding, arterial and venous thrombotic events, and all-cause mortality. Patients with AF and thrombocytopenia experienced a higher 1-year cumulative incidence of major bleeding (13.3% vs 5.7%; P < .0001) and clinically relevant bleeding (24.5% vs 16.7%; P = .005) than the controls. Thrombocytopenia was identified as an independent risk factor for major bleeding (hazard ratio, 2.20; confidence interval, 1.36-3.58; P = .001), with increasing risk based on the severity of thrombocytopenia. The cumulative incidence of arterial thrombosis at 1 year was 3.6% in the group with thrombocytopenia and 1.5% in controls (Gray test, P = .08). These findings suggest that baseline platelet counts are an important biomarker for hemorrhagic outcomes in AF and that the degree of thrombocytopenia is an important factor in determining the level of risk.

BACKGROUND: Although cardiovascular mortality has increased among middle-aged U.S. adults since 2011, how the burden of cardiovascular risk factors has changed for this population by income level over the past 2 decades is unknown.

OBJECTIVE: To evaluate trends in the prevalence, treatment, and control of cardiovascular risk factors among low-income and higher-income middle-aged adults and how social determinants contribute to recent associations between income and cardiovascular health.

DESIGN: Serial cross-sectional study.

SETTING: NHANES (National Health and Nutrition Examination Survey), 1999 to March 2020.

PARTICIPANTS: Middle-aged adults (aged 40 to 64 years).

MEASUREMENTS: Age-standardized prevalence of hypertension, diabetes, hyperlipidemia, obesity, and cigarette use; treatment rates for hypertension, diabetes, and hyperlipidemia; and rates of blood pressure, glycemic, and cholesterol control.

RESULTS: The study population included 20 761 middle-aged adults. The prevalence of hypertension, diabetes, and cigarette use was consistently higher among low-income adults between 1999 and March 2020. Low-income adults had an increase in hypertension over the study period (37.2% [95% CI, 33.5% to 40.9%] to 44.7% [CI, 39.8% to 49.5%]) but no changes in diabetes or obesity. In contrast, higher-income adults did not have a change in hypertension but had increases in diabetes (7.8% [CI, 5.0% to 10.6%] to 14.9% [CI, 12.4% to 17.3%]) and obesity (33.0% [CI, 26.7% to 39.4%] to 44.0% [CI, 40.2% to 47.7%]). Cigarette use was high and stagnant among low-income adults (33.2% [CI, 28.4% to 38.0%] to 33.9% [CI, 29.6% to 38.3%]) but decreased among their higher-income counterparts (18.6% [CI, 13.5% to 23.7%] to 11.5% [CI, 8.7% to 14.3%]). Treatment and control rates for hypertension were unchanged in both groups (>80%), whereas diabetes treatment rates improved only among the higher-income group (58.4% [CI, 44.4% to 72.5%] to 77.4% [CI, 67.6% to 87.1%]). Income-based disparities in hypertension, diabetes, and cigarette use persisted in more recent years even after adjustment for insurance coverage, health care access, and food insecurity.

LIMITATION: Sample size limitations could preclude detection of small changes in treatment and control rates.

CONCLUSION: Over 2 decades in the United States, hypertension increased in low-income middle-aged adults, whereas diabetes and obesity increased in their higher-income counterparts. Income-based disparities in hypertension, diabetes, and smoking persisted even after adjustment for other social determinants of health.

PRIMARY FUNDING SOURCE: National Institutes of Health.

IMPORTANCE: The optimal pharmacologic thromboprophylaxis agent after total hip and total knee arthroplasty is uncertain and consensus is lacking. Quantifying the risk of postoperative venous thromboembolism (VTE) and bleeding and evaluating comparative effectiveness and safety of the thromboprophylaxis strategies can inform care.

OBJECTIVE: To quantify risk factors for postoperative VTE and bleeding and compare patient outcomes among pharmacological thromboprophylaxis agents used after total hip and knee arthroplasty.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study used data from a large health care claims database. Participants included patients in the United States with hip or knee arthroplasty and continuous insurance enrollment 3 months prior to and following their surgical procedure. Patients were excluded if they received anticoagulation before surgery, received no postsurgical pharmacological thromboprophylaxis, or had multiple postsurgery thromboprophylactic agents. In a propensity-matched analysis, patients receiving a direct oral anticoagulant (DOAC) were matched with those receiving aspirin.

EXPOSURES: Aspirin, apixaban, rivaroxaban, enoxaparin, or warfarin.

MAIN OUTCOMES AND MEASURES: The primary outcome was 30-day cumulative incidence of postdischarge VTE. Other outcomes included postdischarge bleeding.

RESULTS: Among 29 264 patients included in the final cohort, 17 040 (58.2%) were female, 27 897 (95.2%) had inpatient admissions with median (IQR) length of stay of 2 (1-2) days, 10 948 (37.4%) underwent total hip arthroplasty, 18 316 (62.6%) underwent total knee arthroplasty; and median (IQR) age was 59 (55-63) years. At 30 days, cumulative incidence of VTE was 1.19% (95% CI, 1.06%-1.32%) and cumulative incidence of bleeding was 3.43% (95% CI, 3.22%-3.64%). In the multivariate analysis, leading risk factors associated with increased VTE risk included prior VTE history (odds ratio [OR], 5.94 [95% CI, 4.29-8.24]), a hereditary hypercoagulable state (OR, 2.64 [95% CI, 1.32-5.28]), knee arthroplasty (OR, 1.65 [95% CI, 1.29-2.10]), and male sex (OR, 1.34 [95% CI, 1.08-1.67]). In a propensity-matched cohort of 7844 DOAC-aspirin pairs, there was no significant difference in the risk of VTE in the first 30 days after the surgical procedure (OR, 1.14 [95% CI, 0.82-1.59]), but postoperative bleeding was more frequent in patients receiving DOACs (OR, 1.36 [95% CI, 1.13-1.62]).

CONCLUSIONS AND RELEVANCE: In this cohort study of patients who underwent total hip or total knee arthroplasty, underlying patient risk factors, but not choice of aspirin or DOAC, were associated with postsurgical VTE. Postoperative bleeding rates were lower in patients prescribed aspirin. These results suggest that thromboprophylaxis strategies should be patient-centric and tailored to individual risk of thrombosis and bleeding.

BACKGROUND: Days at home (DAH) represents an important patient-oriented outcome that quantifies time spent at home after a medical event; however, this outcome has not been fully evaluated for low-surgical-risk patients undergoing transcatheter aortic valve replacement (TAVR). We sought to compare 1- and 2-year DAH (DAH365 and DAH730) among low-risk patients participating in a randomized trial of TAVR with a self-expanding bioprosthesis versus surgical aortic valve replacement (SAVR).

METHODS: Using Medicare-linked data from the Evolut Low Risk trial, we identified 619 patients: 606 (322 TAVR/284 SAVR) and 593 (312 TAVR/281 SAVR) were analyzed at 1 and 2 years, respectively. DAH was calculated as days alive and spent outside a hospital, inpatient rehabilitation, skilled nursing facility, long-term acute care hospital, emergency department, or observation stay. Mean DAH was compared using the t test.

RESULTS: The mean (SD) age and female sex were 74.7 (5.1) and 74.3 (4.9) years and 34.6% (115/332) and 30.3% (87/287) in TAVR and SAVR, respectively. Postprocedural discharge to rehabilitation occurred in ≤3.0% (≤10/332) in TAVR and 4.5% (13/287) in SAVR. The mean DAH365 was comparable in TAVR versus SAVR (352.2±45.4 versus 347.8±39.0; difference in days, 4.5 [95% CI, 2.3-11.2]; P=0.20). DAH730 was also comparable in TAVR versus SAVR (701.6±106.0 versus 699.6±94.5; difference in days, 2.0 [-14.1 to 18.2]; P=0.81). Secondary outcomes DAH30 and DAH90 were higher in TAVR (DAH30, 26.0±3.6 versus 20.7±6.4; difference in days, 5.3 [4.5-6.2]; P<0.001; DAH90, 85.1±8.3 versus 78.7±13.6; difference in days, 6.4 [4.6-8.2]; P<0.001).

CONCLUSIONS: In the Evolut Low Risk trial linked to Medicare, low-risk patients undergoing TAVR spend a similar number of days at home at 1 and 2 years compared with SAVR. Days spent at home at 30 and 90 days were higher in TAVR. In contrast to higher-risk patients studied in prior work, there is no clear advantage of TAVR versus SAVR for DAH in the first 2 years after AVR in low-surgical-risk patients.

Whether thrombocytopenia substantively increases the risk of hemorrhage associated with anticoagulation in patients with atrial fibrillation (AF) is not established. The purpose of this study was to compare rates of bleeding in patients with AF and thrombocytopenia (platelet count < 100 000/μL) to patients with AF and normal platelet counts (>150 000/μL). We performed a propensity score-matched, retrospective cohort study of adults (n = 1070) with a new diagnosis of AF who received a prescription for an oral anticoagulant between 2015 and 2020. The thrombocytopenia cohort was defined as having at least 2 platelet counts <100 000/μL on separate days in the period spanning the 12 weeks preceding the initiation of anticoagulation to 6 weeks after the initiation of anticoagulation. The primary end point was the 1-year cumulative incidence of major bleeding; secondary end points included clinically relevant bleeding, arterial and venous thrombotic events, and all-cause mortality. Patients with AF and thrombocytopenia experienced a higher 1-year cumulative incidence of major bleeding (13.3% vs 5.7%; P < .0001) and clinically relevant bleeding (24.5% vs 16.7%; P = .005) than the controls. Thrombocytopenia was identified as an independent risk factor for major bleeding (hazard ratio, 2.20; confidence interval, 1.36-3.58; P = .001), with increasing risk based on the severity of thrombocytopenia. The cumulative incidence of arterial thrombosis at 1 year was 3.6% in the group with thrombocytopenia and 1.5% in controls (Gray test, P = .08). These findings suggest that baseline platelet counts are an important biomarker for hemorrhagic outcomes in AF and that the degree of thrombocytopenia is an important factor in determining the level of risk.