This subanalysis of the FADOI-NoTEVole study provides a detailed insight into the practice of Italian physicians regarding the use of pharmacological thromboprophylaxis in IMUs’ inpatients.
Pharmacological thromboprophylaxis was prescribed in about half of the 3017 patients admitted to 38 Italian IMUs without prior anticoagulation. According to the PPS, almost 50% of patients were considered at high risk of VTE and, according to the IBS, less than 8% were considered at high risk for bleeding. Although not specifically requested by the FADOI-NoTEVole study protocol, the adoption of pharmacological thromboprophylaxis during hospitalization was only partially influenced by the VTE and bleeding’s RAMs recommended by current guidelines. [5, 6] Indeed, only 66.8% of patients classified as high risk for VTE, according to the PPS, received thromboprophylaxis. Additionally, the assessment of bleeding risk using the IBS did not appear to impact physicians' decisions. Interestingly, several other features composing PPS, IBS, and other RAMs [7, 8] were associated with a different use of pharmacological prophylaxis. These included the presence of a CVC, a previous VTE event, the diagnosis of ischemic stroke, perceived reduced mobility, and a platelet count not lower than 70.000/mm3 at the time of admission. On the other hand, as expected, a recent former major bleeding event led to a lower prescription of pharmacological thromboprophylaxis.
In previous studies, the use of pharmacological thromboprophylaxis in hospitalized non-surgical patients was highly heterogeneous. In the Endorse study, a multinational cross-sectional study designed to assess the prevalence of VTE risk in the acute hospital care setting, the use of pharmacological thromboprophylaxis was generally low, although the risk of VTE was not negligible. [13] Conversely, in a large prospective Italian cohort study, pharmacological thromboprophylaxis was implemented in more than 80% of patients admitted to an IMU with a PPS equal to or above 4. [14]
Several randomized controlled trials and meta-analyses have clearly shown the efficacy of pharmacological thromboprophylaxis compared to placebo in reducing the risk of VTE in non-surgical patients admitted to the hospital. [4, 15, 16] However, this is associated with an increased risk of bleeding and, in general, it has no effect on reducing all-cause mortality, questioning the real importance of this treatment in medical settings. Thus, tools to assess individual risk of VTE and bleeding may be useful in this setting.
In the last few years, many RAMs evaluating these risks have been developed and validated. However, poor evidence is available assessing their real impact in improving the clinical outcomes of these patients. [10] In a small single-center, prospective, quasi-randomized study, the adoption of the Padua Prediction Score was associated with a 50% reduction in the incidence of VTE (i.e., symptomatic and asymptomatic, mainly distal VTE) compared with clinical judgment, with no differences in terms of bleeding and death from all-cause. [17] In a large RCT, employing a strategy including an electronic alert about the thrombotic risk (assessed through a risk score) versus no alert greatly reduced the occurrence of symptomatic VTE with no increase in the bleeding rate in hospitalized patients. [18]
Our study has some limitations. First, the retrospective design is per definition at risk of bias. Data are acquired from clinical records with the risk of suboptimal reporting. This may lead to possible bias in the post-hoc assessment of the RAMs, but the distribution of the thrombotic and bleeding risk appeared to be in line with the previous literature. Second, it is unclear the time when the thrombotic and hemorrhagic events occurred and if minor or clinically relevant bleedings led to an interruption of pharmacological prophylaxis. Third, the FADOI-NoTEVole study included only patients discharged alive and excluded patients with a life expectancy of less than 3 months who were transferred to the nursing home, or the palliative care service: this resulted in a lack of data regarding mortality rates. Finally, no information was available about the use of mechanical prophylaxis (i.e., intermittent pneumatic compression and elastic stockings) and early mobilization, and if it might have helped to reduce VTE rate in patients without pharmacological prophylaxis.
In conclusion, our analysis showed some factors that may influence physicians’ prescription of pharmacological thromboprophylaxis, underscoring the daily challenges in assessing the appropriateness of pharmacological thromboprophylaxis in IMU’s patients. Single risk factors for VTE and bleeding seem to modify clinicians’ behavior. Of note, PPS seems to be only a partial driver of the use of pharmacological prophylaxis, and IBS does not appear to modify clinicians’ approach at all.