Young-onset dementia

Meet the patient

A 56-year-old primary-school principal is referred to psychiatry by her GP as "burnout, won't engage with CBT". For eighteen months she has made impulsive, out-of-character purchases, told crude jokes in front of parents, and put on a stone eating biscuits by the packet. Her husband says the woman he married "went somewhere" two years ago.^[1][11]

She scores 29 out of 30 on a cognitive screen. The GP took that as reassurance. She is still driving, still doing the school banking, and last week left the gas on.^[1][7]

Two exam questions are now live. Why is 29 out of 30 not reassurance here? And why is the behavioural change the finding, not the score? Everything below answers both at consultant depth.^[1][7][11]

History nugget, and it scores marks: the old word was presenile dementia, a label that did real harm by implying these were just younger cases of "ordinary" senile decline. Rossor's 2010 framing replaced it — under-65 onset is a different mix, not the same disease at a younger age.^[1]

References16ShowHide

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2. [2]Hendriks S, Peetoom K, Bakker C, et al. Global Prevalence of Young-Onset Dementia: A Systematic Review and Meta-analysis JAMA Neurol, 2021.PMID 34279544
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