'Where Did I Put My Keys?' – When Forgetfulness Signals Perimenopause, Not Dementia
Ever found yourself frantically searching for your keys, only to realize they’ve been in your hand the whole time? For many women in perimenopause, this isn’t just a one-off moment of absent-mindedness—it’s a recurring theme. But here’s where it gets controversial: while these memory lapses can feel alarming, they’re often a normal part of the hormonal rollercoaster, not a sign of something more sinister like dementia. Marla Shapiro, CM, CCFP, MHSc, a leading expert in family and community medicine at the University of Toronto, sheds light on this misunderstood phenomenon during her interview at The Menopause Society 2025 Annual Meeting.
Shapiro’s relatable analogy—'If you don’t know where your keys are, that’s fine, but if you find them and don’t know what they’re for, that’s a problem'—perfectly captures the difference between perimenopausal brain fog and genuine cognitive decline. This simple yet powerful distinction is a game-changer for women grappling with the anxiety that often accompanies these symptoms.
The Science Behind the Fog
Perimenopausal brain fog isn’t just 'in your head'—it’s rooted in biology. Fluctuating estrogen levels disrupt neurotransmission and sleep patterns, both of which are critical for memory and concentration. Estrogen receptors are densely packed in brain regions like the hippocampus and prefrontal cortex, which govern memory and cognitive function. When estrogen levels swing wildly, so does your ability to focus and recall information. And this is the part most people miss: poor sleep, often exacerbated during perimenopause, compounds these cognitive challenges, creating a vicious cycle of forgetfulness and fatigue.
Research backs this up. The Study of Women’s Health Across the Nation found that 44% of women in early perimenopause reported forgetfulness, compared to just 31% of premenopausal women. Yet, Shapiro reassures us that these symptoms are usually transient, improving once hormone levels stabilize post-menopause. But here’s the catch: if the fog persists, worsens, or interferes with daily life, it’s time to dig deeper. Persistent symptoms could signal underlying issues like depression, thyroid disorders, or even neurocognitive disorders.
When to Worry (and When Not To)
So, how do you know when to brush off the brain fog and when to seek help? Shapiro offers clear red flags: persistent, progressive, or functionally debilitating symptoms warrant further investigation. For instance, if you’re not just misplacing your keys but also struggling to remember how to drive, it’s time to consult a doctor. Differential diagnoses might include primary depression, neurocognitive disorders, or other medical conditions that mimic perimenopausal symptoms.
A Compassionate Approach
Shapiro emphasizes the importance of addressing the fear first. Many women worry that brain fog is the first sign of dementia or Alzheimer’s. By acknowledging these fears and offering reassurance, clinicians can significantly reduce anxiety. Her 'keys' analogy isn’t just memorable—it’s a practical tool for patients to self-monitor and differentiate between benign forgetfulness and concerning changes.
Food for Thought
Here’s a thought-provoking question: Could society’s tendency to dismiss women’s health concerns as 'just hormones' be preventing us from recognizing when these symptoms are something more serious? Shapiro’s work challenges us to take perimenopausal brain fog seriously while avoiding unnecessary alarm. What’s your take? Do you think we’re striking the right balance, or is there room for improvement in how we approach these symptoms?
Take-Homes At-A-Glance
- Red Flags for Further Investigation: Persistent, progressive, or functionally debilitating symptoms.
- Differential Diagnosis Considerations: Primary depression, neurocognitive disorders, thyroid disorders, and other medical conditions.
- Clinical Pearl: Address fear directly and use relatable analogies to reassure patients.
References
1. Weber MT, Maki PM, McDermott MP. Climacteric. 2022.
2. Karlamangla AS, et al. PLoS One. 2017.
3. Weber MT, et al. Menopause. 2013.
4. Haufe A, Leeners B. J Endocr Soc. 2023.
5. Beccuti G, Ghizzoni L. J Clin Med. 2025.
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