Outcomes of stable and unstable patterns of subjective cognitive decline - results from the Leipzig Longitudinal Study of the Aged (LEILA75+).
BACKGROUND
Subjective cognitive decline (SCD), i.e., the self-perceived feeling of worsening cognitive function, may be the first notable syndrome of preclinical Alzheimer's disease and other dementias. However, not all individuals with SCD progress. Stability of SCD, i.e., repeated reports of SCD, could contribute to identify individuals at risk, as stable SCD may more likely reflect the continuous neurodegenerative process of Alzheimer's and other dementias.


METHODS
Cox regression analyses were used to assess the association between stability of SCD and progression to MCI and dementia in data derived from the population-based Leipzig Longitudinal Study of the Aged (LEILA75+).


RESULTS
Of 453 cognitively unimpaired individuals with a mean age of 80.5 years (SD = 4.2), 139 (30.7 %) reported SCD at baseline. Over the study period (M = 4.8 years, SD = 2.2), 84 (18.5 %) individuals had stable SCD, 195 (43.1 %) unstable SCD and 174 (38.4 %) never reported SCD. Stable SCD was associated with increased risk of progression to MCI and dementia (unadjusted HR = 1.8, 95 % CI = 1.2-2.6; p < .01), whereas unstable SCD yielded a decreased progression risk (unadjusted HR = 0.5, 95 % CI = 0.4-0.7; p < .001) compared to no SCD. When adjusted for baseline cognitive functioning, progression risk in individuals with stable SCD was significantly increased in comparison to individuals with unstable SCD, but not compared to individuals without SCD.


CONCLUSIONS
Our results, though preliminary, suggest that stable SCD, i.e., repeated reports of SCD, may yield an increased risk of progression to MCI and dementia compared to unstable SCD. Baseline cognitive scores, though within a normal range, seem to be a driver of progression in stable SCD. Future research is warranted to investigate whether stability could hold as a SCD research feature.
Institute of Social Medicine, Occupational Health and Public Health (ISAP), University of Leipzig, Leipzig, Germany. Susanne.Roehr@medizin.uni-leipzig.de.
Susanne
http://orcid.org/0000-0001-9385-0669
S
Roehr
Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.|University Hospital Leipzig, Day Clinic for Cognitive Neurology, Leipzig, Germany.
Arno
A
Villringer
Center for Public Mental Health, Gösing a. W., Austria.|Department of Public Health, Clinical and Molecular Medicine, University of Cagliari, Cagliari, Italy.
Matthias C
MC
Angermeyer
Institute of Social Medicine, Occupational Health and Public Health (ISAP), University of Leipzig, Leipzig, Germany.|LIFE - Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany.
Tobias
T
Luck
Institute of Social Medicine, Occupational Health and Public Health (ISAP), University of Leipzig, Leipzig, Germany.
Steffi G
SG
Riedel-Heller
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D058070:Asymptomatic Diseases / Q000523:psychology; D003071:Cognition; D060825:Cognitive Dysfunction / Q000175:diagnosis / Q000523:psychology; D059026:Diagnostic Self Evaluation; D018450:Disease Progression; D005260:Female; D015577:Geriatric Assessment / Q000379:methods; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods
Alzheimer’s disease; Cohort studies; Dementia; Mild cognitive impairment; Outcomes; Progression risk; Subjective cognitive decline