Prediction of docetaxel toxicity in older cancer patients: a Bayesian network approach.

Chemotherapy is an essential therapy in the fight against cancer. Polypathology and polymedication are often encountered in elderly patients, making this population especially at risk for adverse drug reactions, and particularly with cytotoxic drugs. The objective of this study was to build a model to predict high-grade toxicity in elderly patients treated with docetaxel. Data from the trial TAX-108 have been used to create the model. The variable to predict was the occurrence of grade 3 or 4 toxicity. The explanatory variables entered in the model were anthropometric and biological characteristics of patients at inclusion; fragility criteria (SMAF, CIRS-G, performance status); location of the primary tumor; chemotherapy history, radiotherapy or surgery; weekly dose of docetaxel, cumulative dose administered. A Bayesian network model was developed using a global search procedure and an Expectation-Maximization algorithm. A 10-fold cross-validation was performed. A toxicity of grade 3 or higher was observed in 54% of patients. The variables providing the most information were the primary site (19.4%), the dose per course (17.5%), and albuminemia (13.1%). The area under the curve of the model obtained after cross-validation was 74 ± 1.4%. The model built allows classifying correctly 71.21 ± 0.9% of patients in our sample in the cross-validation procedure. The sensitivity and specificity of the model were 75 and 67%, respectively, and the positive and negative predictive values were 73 and 69%. The encouraging results from this first study show that Bayesian networks could help assess the benefit-risk ratio of chemotherapy in elderly patients.

Time in Therapeutic Range of Oral Vitamin K Antagonists in Hospitalized Elderly Patients.

BACKGROUND: Oral vitamin K antagonists (VKAs) are commonly used in older adults. To ensure the efficiency and safety of these drugs, the international normalized ratio (INR) must be monitored. The time in therapeutic range (TTR) is an internationally recommended assessment of the anticoagulation quality. OBJECTIVE: Our study aimed to assess the TTR of VKAs in a hospitalized geriatric population and identify factors associated with low TTR. METHODS: This was a multicenter retrospective study of data from 1899 patients with a mean age of 87 years between 2013 and 2015 in the geriatric units of four French hospitals. The data collection consisted of 2450 VKA prescriptions. We excluded prescriptions with a duration of < 7 days, monitoring with fewer than two INR values and patients with prosthetic heart valves. TTR was assessed using the Rosendaal method. Factors associated with a low TTR (< 50%) were assessed using a non-parametric method. RESULTS: The mean TTR observed in this population was 42.6%. The TTR was < 50% for 62.5% of the patients included in this study. Significant associations were found between TTR < 50% and aspartate transaminase (AST), alkaline phosphatase (ALT), thyroid-stimulating hormone (TSH), prescription duration, fluconazole instauration, hemoglobin, and C-reactive protein (CRP). CONCLUSIONS: Both our results and those in the literature indicate that TTR in geriatric populations is lower than that in the general population. Most patients had an insufficient TTR, exposing them to an increased risk of thromboembolic and hemorrhagic events. These data provide a perspective on poor-quality anticoagulation and illustrates the difficulty of using VKAs in geriatric patients.