factors and chronic kidney disease, or previous carcinoma treated with systemic chemotherapy. Out of the 14 patients who were thought to have AD but had non-supportive investigations, seven cases had normal or isolated raised tau on CSF, four had consecutive CSF examinations which were conflicting, two had positive CSF biomarkers but normal imaging and one had generalised atrophy on MRI with disproportionately enlarged ventricles. Eleven patients presented with a progressive non-fluent aphasia (figure 1, supplementary appendix S2). All had word-finding difficulty with variable grammar and inability to repeat sentences. Eight of the 56 patients with atypical clinical features were classified in more than one atypical subcategory. Table 1 Patient characteristics, source of referral and API indication General Characteristics Result No. female 41 Median presenting age in years (range) [n100] 66.7 (44.5-88.0) Median years of education (range) [n49] 14 (10-21) Median duration of cognitive impairment in 24 (0.5-120) months (range) [n96] Median duration pre-API at IMC (months) [n94] 7.1 (0-84) Median duration post-API at IMC (months) [n94] 8.5 (0.4-22.6)* Source of Referred Patients [n100] Primary care physician 48 Secondary care referral from neurologist / 52 psychiatrist API Indication [n100] SCI†/MCI 33 YOD 42 Atypical clinical features± 56 * The difference between pre and post follow up duration is not significant. Two patients had SCI. † ±25 patients were >65 years without MCI/YOD. API, amyloid-PET imaging; IMC, Imperial Memory Centre; SCI, subjective cognitive impairment; MCI, Mild Cognitive Impairment; YOD, Young Onset Dementia
factors and chronic kidney disease, or previous carcinoma treated with systemic chemotherapy. Out of the 14 patients who were thought to have AD but had non-supportive investigations, seven cases had normal or isolated raised tau on CSF, four had consecutive CSF examinations which were conflicting, two had positive CSF biomarkers but normal imaging and one had generalised atrophy on MRI with disproportionately enlarged ventricles. Eleven patients presented with a progressive non-fluent aphasia (figure 1, supplementary appendix S2). All had word-finding difficulty with variable grammar and inability to repeat sentences. Eight of the 56 patients with atypical clinical features were classified in more than one atypical subcategory. Table 1 Patient characteristics, source of referral and API indication General Characteristics Result No. female 41 Median presenting age in years (range) [n100] 66.7 (44.5-88.0) Median years of education (range) [n49] 14 (10-21) Median duration of cognitive impairment in months (range) [n96] 24 (0.5-120) Median duration pre-API at IMC (months) [n94] 7.1 (0-84) Median duration post-API at IMC (months) [n94] 8.5 (0.4-22.6)* Source of Referred Patients [n100] Primary care physician 48 Secondary care referral from neurologist / psychiatrist 52 API Indication [n100] SCI†/MCI 33 YOD 42 Atypical clinical features± 56 * The difference between pre and post follow up duration is not significant. † Two patients had SCI. ±25 patients were >65 years without MCI/YOD. API, amyloid-PET imaging; IMC, Imperial Memory Centre; SCI, subjective cognitive impairment; MCI, Mild Cognitive Impairment; YOD, Young Onset Dementia
Carswell_et_al_Final_paper_16.08.2017_no_Markup_no_figs_or_supplements.docx