Improving Diagnosis of Functional Cognitive Impairment in Younger Adults in Primary Care: Validation of Cognitive Screening Tools and the 4-Item Geriatric Depression Scale.

BACKGROUND: Cognitive decline is classically attributed to organic causes such as dementia; however, depression can play a role in cognitive decline. OBJECTIVE: To evaluate cognitive screening tools and the 4-item Geriatric Depression Scale (GDS-4) for use in primary care to distinguish cognitive decline secondary to depression. METHOD: Clinical data collected over 2.5 years for assessed patients in a secondary clinical service for younger adults. Cognitive screening tools (General Practitioner Assessment of Cognition, Addenbrooke's Cognitive Examination-III, Rowland Universal Dementia Assessment Scale, Salzburg Dementia Test Prediction) and GDS-4 were analyzed for their accuracy to differentiate patients with cognitive decline due to depression from those with subjective cognitive complaints. RESULTS: 180 young adults seen in a memory clinic setting (< 65 years) were included. These individuals either had a diagnosis of depression (n = 46) or no cognitive impairment on assessment (n = 134) despite having subjective cognitive complaints. All used cognitive tools had poor accuracy in differentiating cognitive decline secondary to depression from subjective cognitive complaints. The GDS-4 alone, however, was able to differentiate with high accuracy (AUC = 0.818) individuals who had cognitive problems secondary to depression. CONCLUSION: Cognitive screening tools used alone are ineffective in discriminating cognitive decline secondary to depression. Incorporating the GDS-4 into the screening process by primary practitioners could facilitate early identification and treatment of depression in younger people, avoiding unnecessary referrals memory services.

Suspected Dementia in Young Adults: Cognitive Screening Tools for Use in Primary Care.

BACKGROUND: Memory complaints are frequent among young adults presenting in general practice. Many of them will have reversable, functional cognitive impairment that can easily be mistaken for dementia. Its accurate and timely identification is warranted to prevent further escalation to overt dementia syndrome. OBJECTIVE: To evaluate the recommended primary care screening cognitive tools for dementia for use in younger people. METHODS: 2.5 years clinical data were collected during the course of ongoing patient care for all assessed face-to-face patients in a secondary care memory service for younger adults. Cognitive screening and assessment tests used in primary [General Practice Assessment of Cognition (GPCOG)] and secondary [Addenbrooke's Cognitive Examination-III (ACE-III), Rowland Universal Dementia Assessment Scale (RUDAS), Salzburg Dementia Test Prediction (SDTP)] care were analyzed for their accuracy to identify dementia and memory complaints. Area under the curve in receiver operating characteristic curves was used to measure predictive value of tests for a clinical diagnosis of dementia. RESULTS: 348 young adults were assessed for cognitive impairment. Following comprehensive Memory Clinic assessments, 241 (69.25%) were diagnosed with memory complaints in the absence of relevant neuropathology and 107 with dementia. GPCOG, especially the informant part, and RUDAS had low accuracy to identify dementia (AUC = 0.465 and AUC = 0.698, respectively). In contrast, ACE-III and SDTP demonstrated the highest accuracy (AUC = 0.799 and AUC = 0.809/0.817, respectively). CONCLUSION: Dementia screening in younger people will benefit from SDTP incorporated as part of the screening cognitive toolset. The national guidance on dementia screening tools, diagnostic pathways, and management should also refer to younger adults.