DOAC benefits maintained in oldest AF, stroke patients

The favourable profile of direct oral anticoagulants (DOAC) over vitamin K antagonists (VKA) was maintained in the oldest patients with atrial fibrillation (AF) and recent stroke, a large observational study has confirmed.

The international research, published in the Annals of Neurology, looked at pooled individual patient data from seven prospective cohorts to investigate real-world performance of DOAC versus VKA in patients aged over 85 years with recent AF and stroke.

During 6,874 patient-years follow-up, the impact of DOAC versus VKA on the hazard for the composite outcome of recurrent stroke, intracranial haemorrhage (ICH) and all-cause death did not differ between patients aged more or less than 85 years (HR 0.65 versus 0.79, respectively).

Analyses on recurrent stroke, ICH and death separately were all consistent with findings of the primary analysis, as were sensitivity analyses using a higher age limit of 90 years as a continuous variable, the researchers said.

DOAC had “a similar net clinical benefit” (a balance of stroke reduction versus ICH risk) in patients aged 85 or over (+1.73 to +2.66) compared to those aged under 85 years (+1.90 to +3.36 events/100 patient-years for ICH-weights 1.5 to 3.1).

“The favourable profile of DOAC was maintained in the oldest old, whether defined as aged 85 or 90 years or older. This observation is highly relevant for clinical practice as it contradicts the assumptions of many clinicians who are reluctant to use DOAC in this age group, particularly in multimorbid patients,” the researchers noted.

“In this context, it is clinically important that the beneficial effect of DOAC over VKA persisted after taking into account the high-risk profile of the oldest old. Reassuringly, simple, adjusted, as well as weighted models which controlled for the non-randomised treatment assignment, all yielded consistent results.”

They also stressed that there was “no signal of a safety concern” regarding ICH risk among the oldest DOAC-treated patients with recent ischaemic stroke.

Jury still out on infection risk with IV iron

Concern about infectious complications of intravenous iron have not been resolved despite a major meta-analysis reviewing data from 40 000 patients in 162 clinical trials. The study found a significant increase in the risk of infections (relative risk, 1.17; 95% CI, 1.04-1.31) with IV iron. However, the authors said that much of the data on which they based their analysis were potentially bias, and infections were often poorly documented because the trials were focused on efficacy.

While there were biologically plausible mechanisms to suggest a link between iron and immune responses and infection risk, more conclusive evidence is required from randomised placebo controlled trials, a commentary in JAMA Network Open suggested

“For the present, clinicians should be cautious and defer IV iron therapy during acute infections,” it concluded.

Early Covid boosters for cancer patients

People with cancer have been reminded of the importance of having a booster dose of Covid vaccine, which may be given as early as two months after completing the primary course of two vaccinations.

At a media briefing on 14 November, Kirsten Pilatti, CEO of the Breast Cancer Network of Australia (BCNA) said it was crucial that people with cancer who were immunocompromised because of treatment received an additional dose of vaccine to provide minimum protection against the virus.,

“Today I want to send a very direct message to anyone, whether you’ve been diagnosed with breast cancer or any other cancers … any other immuno-suppressed. We need you to see the third dose as a very important part of your treatment, not as a booster, but as part of your protection,” she said

“And if someone in your life has been diagnosed with a chronic disease or is in treatment, it is just as essential that you play the role of getting the third dose or the second dose, or the first, to help not only protect yourself, but to protect those people in your life that you love,” she added

Ms Pilatti pointed to ATAGI advice, which recommends that a third dose of COVID-19 vaccine be administered to eligible immunocompromised individuals two to six months after the second dose.

And in exceptional circumstances where more rapid protection is required (e.g. an outbreak setting or a significant increase in immunosuppression such as a patient on chronic immunosuppressive therapy requiring the urgent addition of an additional immunosuppressive agent), ATAGI considers a minimum interval of four weeks between the 2nd and 3rd dose to be acceptable.

ATAGI said it recognised that a longer interval between second and third doses may have confer greater vaccine efficacy. “However, this improved vaccine response needs to be weighed against the possibility that protection against COVID-19 from two doses could remain suboptimal until a third dose is administered,” it advised.