Incident HF an ‘extreme high-risk’ condition
MedWire News: Patients have a markedly increased risk for stroke and death in the month following a new heart failure (HF) diagnosis, say researchers.
Their observational study, involving 51,553 participants of the Diet, Cancer, and Health study, also suggests that treatment with a vitamin K antagonist (VKA) may attenuate this elevated risk.
"While HF increases the risk of mortality, stroke and thromboembolism in general, the 'extreme high-risk' nature of incident HF is perhaps under-recognised in everyday clinical practice," Gregory Lip (University of Birmingham, UK) and colleagues write in BMJ Open.
None of the included study participants had a previous diagnosis of HF or atrial fibrillation (AF), although the researchers note that some may have had undiagnosed incident AF, which could have contributed to both HF and stroke risk.
During the first 30 days after diagnosis, the stroke and death rate was 60.74 per 100 person-years among 1239 participants with incident HF, compared with just 1.07 per 100 person-years among participants without.
The stroke and death rate among participants with HF fell to 14.41 per 100 person-years between 30 days and 6 months after diagnosis, and to 6.42 per 100 person-years at later time points, but the risk remained elevated relative to participants without HF.
The increased risk during the first 30 days after HF diagnosis relative to no diagnosis was evident for ischemic stroke (9.52 vs 0.33 per 100 person-years), hemorrhagic stroke (0.98 vs 0.24 per 100 person-years), and for death (50.90 vs 0.77 per 100 person-years).
However, there was a significant interaction with VKA treatment, such that the risk increase was smaller in patients taking a VKA than in those who were not. This effect persisted in multivariate analysis.
"These findings would have major implications for our approach to management of patients presenting with incident HF, given the high risk of this population for death and stroke, which may be ameliorated by VKA therapy," say the researchers.
The multivariate analysis also revealed the impact of previous stroke or transient ischemic attack, which raised death risk more than twofold and stroke risk more than sixfold.
"Our study shows that incident HF patients with prior stroke represent a very high-risk category of patients, who could be targeted for oral anticoagulation, given the potential reduction in mortality shown by the present analysis," say Lip et al.
"This hypothesis would need to be tested in a clinical trial of patients with HF who have prior stroke, who may benefit from aggressive thromboprophylaxis."
By Eleanor McDermid