Diagnostic impact of [18F]flutemetamol PET in early-onset dementia.

Abstract

BACKGROUND:

Early-onset dementia patients often present with atypical clinical symptoms, hampering an accurate clinical diagnosis. The purpose of the present study was to assess the diagnostic impact of the amyloid-positron emission tomography (PET) imaging agent [18F]flutemetamol in early-onset dementia patients, in terms of change in (confidence in) diagnosis and patient management plan.

METHODS:

This prospective bi-center study included 211 patients suspected of early-onset dementia who visited a tertiary memory clinic. Patients were eligible with Mini Mental State Examination ≥ 18 and age at diagnosis ≤ 70 years and in whom the diagnostic confidence was <90% after routine diagnostic work-up. All patients underwent [18F]flutemetamol PET, which was interpreted as amyloid-negative or amyloid-positive based on visual rating. Before and after disclosing the PET results, we assessed the diagnostic confidence (using a visual analog scale of 0-100%) and clinical diagnosis. The impact of [18F]flutemetamol PET on the patient management plan was also evaluated.

RESULTS:

[18F]flutemetamol PET scans were positive in 133 out of 211 (63%) patients, of whom 110 out of 144 (76%) patients had a pre-PET Alzheimer's disease (AD) diagnosis and 23 out of 67 (34%) patients had a non-AD diagnosis. After disclosure of PET results, 41/211 (19%) diagnoses changed. Overall, diagnostic confidence increased from 69 ± 12% to 88 ± 15% after disclosing PET results (P < 0.001; in 87% of patients). In 79 (37%) patients, PET results led to a change in patient management and predominantly the initiation of AD medication when PET showed evidence for amyloid pathology.

CONCLUSIONS:

[18F]flutemetamol PET changed clinical diagnosis, increased overall diagnostic confidence, and altered the patient management plan. Our results suggest that amyloid PET may have added value over the standardized diagnostic work-up in early-onset dementia patients with uncertain clinical diagnosis. This study provides evidence for the recommendations put forward in the appropriate use criteria for amyloid PET in clinical practice.

TRIAL REGISTRATION:

Nederlands Trial Register NTR3743 . Registered 7 December 2012.

• Authors: Marissa D Zwan, Femke H Bouwman, Elles Konijnenberg, Wiesje M van der Flier, Adriaan A Lammertsma, Frans R J Verhey, Pauline Aalten, Bart N M van Berckel, Philip Scheltens
• Journal: Alzheimer's research & therapy (Alzheimers Res Ther) Vol. 9 Issue 1 Pg. 2 (Jan 17 2017) ISSN: 1758-9193 [Electronic] England
• PMID: 28093088 (Publication Type: Clinical Trial, Journal Article, Multicenter Study)

Chemical References

• Aniline Compounds
• Benzothiazoles
• Fluorine Radioisotopes
• Radiopharmaceuticals
• flutemetamol

Topics

• Age of Onset
• Aged
• Aniline Compounds
• Benzothiazoles
• Brain (diagnostic imaging)
• Dementia (diagnostic imaging)
• Female
• Fluorine Radioisotopes
• Humans
• Male
• Middle Aged
• Positron-Emission Tomography
• Prospective Studies
• Radiopharmaceuticals