Brain fog is a common complaint, but what is it really, and how can we manage it?

More and more perimenopausal women are seeking help for “brain fog”, possibly frightened about the risk of dementia and looking for fixes in hormone therapy and testosterone. But brain fog is a cloudy term, from its definition down to its treatment.

So what do we know?

“There was very little research on this topic a decade ago, and it’s starting to slowly trickle in now,” said Associate Professor Caroline Gurvich, a clinical neuropsychologist and deputy director of the HER Centre Australia at Monash University.

In contrast, the amount of content on social media about brain fog and menopause looks more like a flood.

Around two in three women experience brain fog in perimenopause, and interest in the issue is growing, Professor Gurvich said.

In April, she and her colleagues summed up the latest evidence in The Lancet Obstetrics & Gynaecology.

Studies have found memory-related symptoms were reported in between 26% and 95% of perimenopausal participants. Meanwhile, concentration difficulties have been recorded in between 52% and 90% of perimenopausal women.

Although, because the studies are cross-sectional, the trajectory of these symptoms from premenopause and perimenopause to postmenopause is still unknown, Professor Gurvich noted.

Another issue is that “brain fog” can mean different things to different people.

Patients may use it in conditions ranging from long covid and fibromyalgia to traumatic brain injury and postpartum baby brain.

Because the term doesn’t have an official definition in the context of menopause, Professor Gurvich and colleagues developed their own. They defined brain fog in perimenopause as an issue of subjective cognitive decline, but “generally not a significant objective cognitive change,” she said.

It can fluctuate, either daily or across a menstrual cycle. And, importantly, it causes mild to substantial distress and affects quality of life.

Dr Karen Magraith, past president of the Australasian Menopause Society and Tasmanian GP, said that she also uses the term “cognitive concerns.”

“I find it helpful to actually ask the patient what she means by brain fog, because it could mean something a little bit different to different people,” she said.

Women in studies experienced symptoms ranging from poor memory and difficulty concentrating to mental fatigue and problems with planning, organising and making decisions, ​Professor Gurvich and her colleagues found.

​​There was often​ a disconnect between participants’ subjective concerns and their objective performance on tests.

“That kind of mismatch between people’s subjective experience and objective cognition isn’t unique to menopause,” Professor Gurvich said.

​​Participants could perform well on tests in a structured environment, when getting assessed, by concentrating hard and finding workarounds, she said. ​​​

​​“But in day-to-day life, when we have lots of other competing demands, it stretches us, and then we feel those more subtle changes that might manifest as word retrieval difficulties, forgetfulness, or difficulty juggling tasks.”

Even if subjective, the symptoms can still be distressing, to the point where some women quit their jobs, Professor Gurvich said, emphasising the need to validate and reassure them.

“It’s something that’s very real for women…It really can make them feel inadequate. It can impact their self-esteem.”

​​What does this mean for dementia?​

One big source of anxiety for many women is whether brain fog is the first sign of dementia – and it’s important to reassure them that it’s not, Dr Magraith said.

“In fact, there’s no proven link between brain fog during perimenopause and the risk of dementia,” she said.

While it’s important to take complaints of brain fog seriously, women need to be reassured they aren’t on the downward track to dementia, she said.

Dr Magraith sometimes explains the change by saying that as hormones fluctuate during perimenopause, the brain is “trying to catch up.”

“Their brain is trying to get used to the fluctuations, and it can make things more difficult,” she said, noting that resonates with patients who can feel that fluctuation, and may notice that they have worse brain fog at different times of their menstrual cycle, for example.

Professor Gurvich said oestrogen plays a “really important role” in the brain.

“Dopaminergic, serotonergic systems, glutamatergic, GABAergic, all these neurotransmitter systems that are really crucial for helping us think are also interacted with and modulated by oestrogen,” she said.

“So when we have changes in oestrogen, it makes sense that it could impact our cognition and our experience of cognition.”

​​Ruling out other causes​

The first step is a comprehensive ​​assessment​ to look for physical or psychological factors that might be causing cognitive symptoms​.

“Before we attribute it all to hormones, I think we need to be thinking about whether there might be other medical things that might be contributing. For example, are they iron deficient? Do they have a thyroid disorder?” Dr Magraith said.

Sleep disturbances – often from vasomotor symptoms – mental health issues, lifestyle factors and life stressors can all also contribute to mental fogginess.

Women are especially at risk of mood disorders in perimenopause. Depression risk is increased even in women who haven’t had depression before – and depression is associated with cognitive symptoms, although it’s unclear if treating depression in menopause will help with those issues, Professor Gurvich and colleagues noted.

“If the patient says they’re experiencing brain fog, then we need to listen to them and validate that,” Dr Magraith said. “We don’t have to necessarily do a formal cognitive assessment unless we are worried about something more serious.”

Dementia vs cognitive symptoms related to ​menopause​

To help determine whether the issue at hand is due to ​menopause​ or dementia, there are some key warning signs to watch out for.

Menopausal​ cognitive symptoms​ generally occur at a younger age than the average age of dementia onset, so in their 40s or 50s compared with 65 or later.

“So age is a differential factor, but not diagnostic,” Professor Gurvich said.

Patients with dementia typically have less insight into their condition too.

With dementia, the patient’s partner is often the one raising concerns, whereas with brain fog, women tend to be more critical of their own abilities than anyone else in their lives is, she said.

Another sign to look out for is whether the cognitive issues are consistent.

“Cognitive symptoms in ​​menopause seem to fluctuate,” Professor Gurvich said. “People have trouble with word finding, and then they’re okay again. And it might fluctuate across a day or two days or a menstrual cycle – if they still have a menstrual cycle.”

“Whereas, if it is the early stages of dementia, it’s progressive, it’s getting worse, it’s neurodegenerative,” said Professor Gurvich.

Dementia also usually shows up on objective measures in ways that ​brain fog in ​menopause does not.

“If someone does have young, early-onset dementia. It’s generally accompanied by some mood changes or personality changes or behavioural changes,” she added.

Does MHT help with brain fog?

There is no clear evidence that MHT helps with cognitive function, but ​many​​ women say it helps, Professor Gurvich and Dr Magraith said.

“We don’t have strong evidence that MHT improves subjective symptoms of brain fog, or objective measures of cognition during perimenopause. However, very little specific research has been done addressing these questions,” Dr Magraith said.

​​”Anecdotally many women report benefit, and it’s logical that if MHT is helping vasomotor symptoms and sleep, it may also help brain fog.”​

​​​“​Even though MHT is not specifically recommended in guidelines for treatment of brain fog, we can consider a trial if women would like to after a discussion about the evidence base, risks and benefits of MHT​,​”​ Dr Magraith said. ​ 

Hormonal contraceptives may also be helpful.

“If women are having cyclic or fluctuating symptoms during perimenopause some of them may benefit from cycle control, for example with a contraceptive pill formulation. Another option is MHT comprising systemic estrogen and cyclic progestogen, or a progestogen IUD,” Dr Magraith said.

Testosterone is not recommended for cognitive symptoms, and its only evidence-based use is for low libido in postmenopausal women, she added.

What other strategies are there?

​​​Dr Marita Long, head of the Jean Hailes Women’s Brain Care Clinic and a GP, said reassurance can go a long way. ​​

​​​​​“Women can be very alarmed by the cognitive changes they experience in the menopausal transition and it is our job to reassure them that their brains are still very healthy and functional,” Dr Long said. ​​
​​​
​“Offering women some support to ‘self care,’ delegate tasks out if they can, try to focus on one task at a time, perform cognitively demanding work at the time of day that works best for them, use reminders/lists and for some women CBT may be helpful to manage some of the anxiety that can accompany these symptoms.​​”​​

Improving cognitive health more broadly

“Exercise is a good intervention to recommend for its general cognitive benefits, both for symptoms in the short term and to reduce risk of dementia in the longer term,” Dr Magraith said.

​​​Dr Long adds that while brain fog is transitional, it is an optimal time to explore and address any modifiable risk factors for dementia, particularly vascular risk factors.​​

​​​​​​“Encouraging women to eat a varied diet, sleep well, exercise regularly and limit alcohol is always a good place to start,” she said​​.​​