Average Time to Diagnosis Is 3.5 Years Across All Types of Dementia

FRIDAY, Aug. 1, 2025 (HealthDay News) — The mean time to diagnosis (TTD) for dementia is 3.5 years across all types of dementia, according to a review published online July 27 in the International Journal of Geriatric Psychiatry.

Olubunmi Kusoro, from University College London, and colleagues conducted a systematic review of quantitative studies on TTD in dementia and factors associated with its duration. TTD was defined as the interval between symptom onset and final diagnosis. Thirteen studies reporting data on 30,257 participants were included, with age at onset ranging from 54 to 93 years.

The researchers found that the average mean TTD across all types of dementia was 3.5 years in meta-analysis pooling of 10 studies. TTD in young-onset dementia was 4.1 years in analyses of six studies. Factors influencing TTD were inconsistent, but consistent associations were seen for younger age at onset and having frontotemporal dementia with a longer interval to diagnosis.

“To speed up dementia diagnosis, we need action on multiple fronts,” lead author Vasiliki Orgeta, Ph.D., also from University College London, said in a statement. “Public awareness campaigns can help improve understanding of early symptoms and reduce stigma, encouraging people to seek help sooner. Clinician training is critical to improve early recognition and referral, along with access to early intervention and individualized support so that people with dementia and their families can get the help they need.”

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