Harris DE, Thayer D, Wang T, Brooks C, Murley G, Gravenor M, Hill NR, Lister S, Halcox J.
European Heart Journal – Cardiovascular Pharmacotherapy (2019) doi.org/10.1093/ehjcvp/pvz071
In patients with non-valvular atrial fibrillation (NVAF) prescribed warfarin, the UK National Institute of Health and Care Excellence (NICE) defines poor anticoagulation as a TTR of < 65%, any 2 INRs within a 6 month period of ≤ 1.5 (“low”), 2 INRs ≥5 within 6months, or any INR ≥ 8 (“high”).
Our objectives were to (i) quantify the number of patients with poor INR control and (ii) describe the demographic and clinical characteristics associated with poor INR control.
Linked anonymised health record data for Wales (2006-2017) was used to evaluate patients prescribed warfarin who had at least 6 months of INR data.
32,380 patients were included. In total, 13,913 (43.0%) patients had at least one of the NICE markers of poor INR control. Importantly, in the 24,123 (74.6%) of the cohort with an acceptable TTR (≥65%), 5,676 (23.5%) had either low or high INR readings at some point in their history. In a multivariable regression female gender, age (≥75), excess alcohol, diabetes heart failure, ischaemic heart disease and respiratory disease were independently associated with all markers of poor INR control.
Acceptable INR control according to NICE standards is poor. Of those with an acceptable TTR (>65%) one quarter still had unacceptably low or high INR levels according to NICE criteria. Thus, only using TTR to assess effectiveness with warfarin has the potential to miss a large number of patients with non-therapeutic INRs who are likely to be at increased risk.
COVID-19 vaccine uptake, effectiveness, and waning in 82,959 health care workers: A national prospective cohort study in Wales
21 April 2022
Understanding the effectiveness and uptake of the COVID-19 vaccines in the population was a vitally important area of study as the rollout progressed. This was particularly the case for the most...
Educational and health outcomes of schoolchildren in local authority care in Scotland: A retrospective record linkage study
20 April 2022
The start that children experience in life can have a profound impact on their future prospects. Small studies have shown that children in care are more likely to be absent from school and have...
The National Neonatal Research Database: Making faster, safer and more efficient improvements to neonatal healthcare
8 April 2022
Neena Modi, Professor of Neonatal Medicine at Imperial College London, speaks to us about the NNRD - a longitudinal, whole-population dataset that brings real-time information across the UK to...