ABSTRACT
BACKGROUND: Use of vitamin K antagonists (VKAs) for stroke prophylaxis in patients with non-valvular atrial fibrillation (NVAF) necessitates frequent monitoring of the international normalized ratio (INR) to avoid the increased risk of hemorrhage associated with excess anticoagulation, or ischemic stroke due to insufficient anticoagulation. We therefore developed a model to estimate the excess morbidity attributable to inadequate INR control in NVAF populations. METHODS: Equations expressing the risk of cerebrovascular events as a function of INR were generated using published data. Additional functions were developed to estimate the excess risk attributable to inferior INR control, using the clinical trial setting as the reference. RESULTS: The derived risk functions were applied to French NVAF patients receiving anticoagulation in routine medical practice. This population achieved a time in therapeutic range (INR 2.0-3.0) of 59%, compared with 68% time in therapeutic range (TTR) in the SPORTIF III and V clinical trials. However, there was considerable variation in the TTR among patients in routine care, of whom 36% were in range for less than 50% of the time. Among this latter group, the relative risk, compared with the clinical trial setting, was 1.47 for ischemic stroke and 2.68 for intracranial hemorrhage. Conversely, for patients achieving a TTR greater than 50%, the relative risks for ischemic stroke and intracranial hemorrhage were 0.99 and 1.16, respectively. CONCLUSIONS: This model permits estimation of the excess risk attributable to inferior INR control in NVAF populations receiving VKA anticoagulation, and has implications for public health planning and management.
Subject(s)
Anticoagulants/therapeutic use , Atrial Fibrillation/drug therapy , Atrial Fibrillation/epidemiology , International Normalized Ratio/statistics & numerical data , Stroke/epidemiology , Blood Coagulation/drug effects , Brain Ischemia/epidemiology , Brain Ischemia/prevention & control , Cerebral Hemorrhage/epidemiology , Cerebral Hemorrhage/prevention & control , France/epidemiology , Humans , Models, Statistical , Morbidity , Public Health , Quality of Health Care , Risk Factors , Stroke/prevention & control , Vitamin K/antagonists & inhibitorsABSTRACT
This study aimed at estimating the paediatric RotaVirus GastroEnteritis (RVGE) burden in children aged up to 5 years, and at evaluating health and economic benefits of a universal infant vaccination with a pentavalent rotavirus vaccine, in France. A decision analytic model was constructed considering a cohort of French children from birth to 5 years old. In the absence of a universal rotavirus immunisation programme, the model predicts that of every new French birth cohort, 336,738 children would present a RVGE case, which would result in 33,386 hospitalisations, 14 deaths and more than 279,000 work days lost for the parents. The management of these RVGE cases would cost 63 million euro to the National Healthcare Payer and would reach up to 117 million euro when all indirect costs were included. The introduction of a universal rotavirus vaccination would avoid 249,400 RVGE cases and consequently about 25,700 hospitalisations, 6000 nosocomial infections, 81,200 emergency visits, 39,900 general practitioner or paediatrician consultations, 11 deaths and 206,700 parental work days lost. RVGE total costs would be reduced by 47 million euro for the National Healthcare Payer and by 88 million euro from the Societal perspective. Therefore, a routine universal rotavirus vaccination programme represents an opportunity to significantly reduce the high paediatric RVGE burden in France.
