Risk factors for cancer‐associated venous thromboembolism: The venous thromboembolism prevention in the ambulatory cancer clinic (VTE‐PACC) study

Abstract

Background The Khorana Score is a validated risk score for predicting 6‐month incidence of cancer‐associated venous thromboembolism (CAT) among patients starting chemotherapy. Venous thromboembolism (VTE) risk factors important in the general population, including age, sex, prior VTE, and hospitalization, are not included in this score, their association with VTE in cancer patients is unknown. Objective To examine risk factors for CAT and the impact of incorporating longitudinal hospitalization into risk assessment. Methods Risk factors were recorded among patients starting chemotherapy at a single institution from 2012‐14. Hospitalization and time‐periods after hospitalization were assessed as time‐varying covariates. Logistic regression was used to determine factors related to 6‐month CAT risk (the Khorana Score endpoint). Proportional hazard models were used for risk factor identification throughout the 3‐year observation period. Results Among 1,583 patients starting chemotherapy (mean age 60, 48% male), 187 developed CAT (11.8%) with 129 (69%) cases occurring within 6 months of starting chemotherapy. In the 6‐month analysis, no additional risk factors were associated with CAT. In the 3‐year analysis, male sex (HR 1.57, 95%CI 1.21, 2.07), prior VTE (HR 2.12, 95%CI 1.41, 3.18), and hospitalization (HR 2.69, 95%CI 1.92, 3.75) were associated with increased hazard of CAT, adjusting for risk factors in the Khorana score. Conclusions When time‐to‐event data were incorporated into CAT risk assessment, male sex, prior VTE, and hospitalization were important risk factors. These data highlight the need to consider dynamic methods for assessing VTE risk in cancer patients, with particular attention to the period around hospitalizations.

Risk factors for venous thromboembolism in metastatic colorectal cancer with contemporary treatment: A SEER‐Medicare analysis

“…Prior history of VTE is an established risk factor for future VTE in the general population, hospitalized patients, and patients undergoing cancer surgery, 41 , 42 with growing evidence supporting an association with VTE in ambulatory cancer patients on treatment beyond traditional risk models such as the Khorana score. 43 …”

Venous thrombosis risk during and after medical and surgical hospitalizations: The medical inpatient thrombosis and hemostasis (MITH) study

“…Unique among vascular diseases, VTE has effective pharmacologic prevention strategies (albeit at the cost of increased bleeding) and risk is often concentrated around identifiable and sometimes transient risk factors 5 . Provoked VTE are those events in which one or more clear temporally associated risk factors are identified, for example surgery, fracture, or hospitalization 6 …”

“…5 Provoked VTE are those events in which one or more clear temporally associated risk factors are identified, for example surgery, fracture, or hospitalization. 6 Thirty to seventy percent of all VTE events are associated with hospitalization and the time periods after hospitalization. 7,8 Efforts to prevent VTE in hospitalized patients include administration of low-dose anticoagulants, but the benefit of this strategy in the post-discharge period is less clear.…”

Development and validation of a prediction model of deep venous thrombosis for patients with acute poisoning following hemoperfusion: a retrospective analysis

“…5 At present, the most researched populations internationally primarily include patients with orthopedic major surgery, those with tumors, critical patients, and those who are pregnant or in childbirth. [6][7][8][9][10][11] Because these populations are different, the risk factors affecting them are varied. Among patients with acute poisoning, especially paraquat poisoning and other patients with poisoning without specific antidotes, receiving hemoperfusion as early as possible is the most timely and effective treatment available.…”