AFFINITY Trial: Fluoxetine After Stroke and Published Results
Stroke is one of the leading causes of long-term disability worldwide, and effective treatments that improve recovery after stroke remain an important area of clinical research. The AFFINITY Trial was established to investigate whether fluoxetine, an established antidepressant medicine, could improve recovery when started soon after a stroke.
The Assessment of Fluoxetine in Stroke Recovery (AFFINITY) Trial was a large, multi-centre clinical trial involving 1,280 participants across Australia, New Zealand and Vietnam. The study investigated whether fluoxetine, started within the first two weeks following stroke and continued for six months, could improve functional recovery compared with a placebo.
Published Results
The completed trial found no improvement in functional recovery with fluoxetine compared with placebo. Falls, fractures and seizures were more frequent in the fluoxetine group. Read the primary results published in The Lancet Neurology (2020) and the ANZCTR record ACTRN12611000774921 for the evidence.
What Was the AFFINITY Trial?
AFFINITY was an investigator-driven, randomised, double-blind, placebo-controlled clinical trial. It was designed to provide reliable evidence about the potential effects of routine fluoxetine treatment in people recovering from a recent stroke.
Participants were randomly assigned to receive either fluoxetine 20 mg once daily or a matching placebo for 180 days. Neither participants nor relevant study personnel knew which treatment had been assigned, helping to reduce potential bias when assessing outcomes.
Why Was the Study Needed?
Recovery following stroke can vary considerably between individuals, and persistent weakness, communication difficulties, cognitive problems and other neurological impairments can have a major effect on daily life. At the time the AFFINITY Trial was developed, there was a need for better evidence about treatments that might support functional recovery after stroke.
Earlier research had suggested that fluoxetine might have beneficial effects on recovery in some stroke patients, particularly those with motor impairment. The AFFINITY Trial was designed to investigate this question in a much larger population using a rigorous clinical trial methodology.
How Was the Study Conducted?
The trial recruited adults who had experienced a recent ischaemic or haemorrhagic stroke and had measurable neurological deficits. Eligible participants were randomly allocated to fluoxetine or placebo and followed for up to one year after randomisation. The study included several important stages:
- Recruitment of eligible adults following recent stroke
- Randomisation to fluoxetine or matching placebo
- Daily treatment for 180 days
- Assessment of functional recovery at 180 days
- Additional follow-up at 28, 90 and 365 days
- Monitoring of health outcomes and serious adverse events
- Assessment of healthcare costs and cost-effectiveness
What Did the Trial Measure?
The main outcome of the AFFINITY Trial was functional outcome at 180 days after randomisation. Functional status was assessed using the simplified modified Rankin Scale questionnaire (smRSq). The study also collected information about a broad range of other outcomes to provide a more complete picture of recovery and health following stroke. These included:
- Survival
- Mood and depressive symptoms
- Cognitive function
- Communication
- Motor function
- Overall health status
- Health-related quality of life
- Functional recovery at one year
- Fatigue
- Serious adverse events
- Healthcare costs
- Cost-effectiveness
Who Conducted the AFFINITY Trial?
The AFFINITY Trial was an Australasian investigator-driven study coordinated through the Stroke Research Group at the Harry Perkins Institute of Medical Research and Sir Charles Gairdner Hospital in Western Australia.
The trial was led by Associate Professor Maree Hackett of The George Institute for Global Health and The University of Sydney and Professor Graeme Hankey of The University of Western Australia and Sir Charles Gairdner Hospital.
The study was funded by the National Health and Medical Research Council (NHMRC) and involved participating stroke units in Australia, New Zealand and Vietnam.
Study Timeline
The AFFINITY Trial recruited participants from January 2013 to June 2019. Participants received their allocated treatment for six months and continued to be followed until 365 days after randomisation. The study protocol provided a structured framework for evaluating the potential benefits and risks of fluoxetine treatment following recent stroke, with functional recovery at six months serving as the primary outcome.
Explore the AFFINITY Trial
The AFFINITY website provides information about the study protocol, trial design, participant eligibility and other aspects of the research. Detailed pages explain how the study was structured, including its inclusion and exclusion criteria, treatment groups, outcome measures and follow-up schedule. Explore the study information to learn more about the research methodology and the objectives of the AFFINITY Trial.
Read the study design overview for a quick guide, the protocol and methods for technical details, and investigators and funding for information about the research team.
