Cognitive assessment across normal aging and subjective cognitive decline using PGIMS and Stroop color-word test: A cross-sectional study

Background

Early detection of abnormal neurodegeneration amidst normal cognitive aging is crucial. Subjective cognitive decline (SCD) may indicate Alzheimer's disease (AD) onset. Thus, we assess cognitive domains across the aging spectrum using simple neuropsychological tools.

Methodology

In this cross-sectional study, we examined 44 SCD individuals, 40 older controls (OC), and 20 young controls (YC) aged 40–60 years. Participants underwent demographic assessments, history evaluations, and screening using the Geriatric Depression and Anxiety Scales and the Clinical Dementia Rating (CDR) scale. Cognitive assessments included the PGI Memory Scale (PGIMS) and Stroop test, measuring memory and executive function.

Results

Both SCD and OC scored notably lower than YC in verbal retention of dissimilar words (Coefficient: -0.34, 95 % CI: -0.64 to -0.04) and in the Stroop word test (SCD Co-efficient: -0.08, 95 % CI: -0.16 to 0.01 and OC Co-efficient: -0.07, 95 % CI: -0.14 to 0.01) and the Stroop Color test (SCD Coefficient: -0.19; 95 % CI: -0.31 to -0.07 and OC Co-efficient: -0.10, 95 % CI: -0.21 to 0.01). SCD individuals scored significantly lower in the Stroop color-word tests (SCWT), and delayed recall memory in PGIMS (Co-efficient: -0.11, 95 %CI: -0.21 to -0.02) and -0.62; 95 % CI: -1.19 to -0.04, respectively).

Conclusion

Cognitive aging affects auditory short-term memory and processing speed while preserving mental balance. SCD is marked by deficits in delayed recall and executive function, suggesting early cognitive decline. Identifying these impairments with simple neuropsychological tools aids early detection, but further research with larger samples, longitudinal data, and biomarkers is needed to refine diagnosis and track neurodegeneration.