Six-month follow-up of patients with in-hospital thrombocytopenia during heparin-based anticoagulation (from the Complications After Thrombocytopenia Caused by Heparin [CATCH] registry)

Heparin-Induced Thrombocytopenia After Cardiac Surgery-A Statewide Review of Health Care Utilization

BACKGROUND

Despite its severe consequences, clinical and economic impacts of heparin-induced thrombocytopenia (HIT) after cardiac operations have not been well characterized. This study assessed statewide incidence, outcomes, and resource consumption associated with HIT after cardiac operations.

METHODS

This was a retrospective investigation of cardiac surgery patients using the Maryland Health Services Cost Review Commission's database from 2012 to 2020. Health care costs, utilization, and outcomes for those who experienced postoperative HIT were compared with propensity score-matched controls.

RESULTS

Of 33 583 cardiac surgery patients, 184 (0.55%) were diagnosed with postoperative HIT. Compared with non-HIT patients, HIT patients were significantly more likely to be in the oldest age group (>80 years; P < .001) and to have greater severity of illness at admission (P < .001). HIT was associated with a longer hospitalization (21 vs 7 days; P < .001), greater mortality (13.6% vs 2.3%; P < .001), and greater hospital charges ($123 160 vs $45 303; P < .001), even after propensity score matching. Readmission rates were not significantly different, however, and readmission hospital charges did not significantly differ between HIT and non-HIT patients.

CONCLUSIONS

In addition to worse outcomes, HIT was associated with higher costs during index admissions but not during readmissions of cardiac surgery patients. Strategies to minimize HIT could yield better outcomes and reduced costs, particularly relevant for health care systems seeking improved value-based care while reducing unnecessary hospitalizations.

A preliminary randomised controlled study of short-term Antrodia cinnamomea treatment combined with chemotherapy for patients with advanced cancer

Background

Antrodia cinnamomea (AC) is a popular medicinal mushroom in Taiwan that has been widely used for treatment of various cancers. Few clinical studies have reported its application and efficiency in therapeutic chemotherapy strategies. We performed a double-blind, randomized clinical study to investigate whether AC given for 30 days had acceptable safety and efficacy in advanced cancer patients receiving chemotherapy.

Methods

Patients with advanced and/or metastatic adenocarcinoma, performance status (PS) 0–2, and adequate organ function who had previously been treated with standard chemotherapy were randomly assigned to receive routine chemotherapy regimens with AC (20 ml twice daily) orally for 30 days or placebo. The primary endpoint was 6-month overall survival (OS); the secondary endpoints were disease control rate (DCR), quality of life (QoL), adverse event (AE), and biochemical features within 30 days of treatment.

Results

From August 2010 to July 2012, 37 subjects with gastric, lung, liver, breast, and colorectal cancer (17 in the AC group, 20 in the placebo group) were enrolled in the study. Disease progression was the primary cause of death in 4 (33.3 %) AC and 8 (66.7 %) placebo recipients. Mean OSs were 5.4 months for the AC group and 5.0 months for the placebo group (p = 0.340), and the DCRs were 41.2 and 55 %, respectively (p = 0.33). Most hematologic, liver, or kidney functions did not differ significantly between the two groups, but platelet counts were lower in the AC group than in the placebo group (p = 0.02). QoL assessments were similar in the two groups, except that the AC group showed significant improvements in quality of sleep (p = 0.04).

Conclusions

Although we found a lower mortality rate and longer mean OS in the AC group than in the control group, A. cinnamomea combined with chemotherapy was not shown to improve the outcome of advanced cancer patients, possibly due to the small sample size. In fact, the combination may present a potential risk of lowered platelet counts. Adequately powered clinical trials will be necessary to address this question.

Trial registration

ClinicalTrials.gov NCT01287286.

Pitfalls in the diagnosis of heparin-Induced thrombocytopenia: A 6-year experience from a reference laboratory

Heparin-induced thrombocytopenia (HIT) is caused by platelet-activating antibodies against complexes of platelet factor 4 (PF4) and heparin. The diagnosis of HIT is contingent on accurate and timely laboratory testing. Recently, alternative anticoagulants for the treatment of HIT have been introduced along with algorithms for better HIT diagnosis. However, the increased reliance on immunoassays for the diagnosis of HIT may have harmful consequences due to the high rate of false positive results. To compare trends and implications of current HIT testing approaches, we analyzed results over a six-year period from the McMaster University Platelet Immunology Reference Laboratory. From 2008 to 2013, 8,546 samples were investigated for HIT using both an in-house IgG-specific anti-PF4/heparin enzyme immunoassay (EIA) and the serotonin-release assay (SRA). Of 8,546 samples tested, 13.4% were true-positives (positive in both assays); 65.6% were true-negatives (negative in both assays); 20.9% were presumed false positive for HIT (EIA-positive/SRA-negative); and 0.2% were EIA-negative/SRA-positive. The frequency of EIA-positive/SRA-negative results increased over time (from 12.9% in 2008 to 22.9% in 2013). We found that the number of SRA-negative samples was reduced from referring centers that used an immunoassay as an initial screen; however, 41% of those samples tested negative in the immunoassay and in the SRA at the reference laboratory. The suspicion of HIT continues at a high rate and the agreement between the EIA and SRA test results remains problematic.

Antithrombotic therapy in heparin-induced thrombocytopenia: guidelines translated for the clinician

Heparin-induced thrombocytopenia (HIT) is a clinicopathologic syndrome initiated by heparin exposure and characterized by thrombocytopenia and paradoxical thrombophilia. HIT is mediated by the formation of antibodies against the platelet factor 4/heparin complex, which leads to platelet activation, thrombin generation, and potentially fatal thrombotic sequelae. The clinical presentation of HIT is variable and can be easily overlooked. Although a number of functional and antigen-based immunoassays have been developed to detect the presence of HIT antibodies, initial diagnosis is often based on recognition of thrombocytopenia in the appropriate clinical context and later confirmed with immunologic testing. Given the serious clinical consequences of HIT, immediate cessation of heparin products and administration of non-heparin anticoagulants are crucial components of treatment. We provide a review of the clinical syndrome and practical summary of treatment recommendations from the most recent 2012 American College of Chest Physicians evidence-based guidelines for the treatment and prevention of HIT.