ASSOCIATION OF SUBJECTIVE COGNITIVE DECLINE WITH RISK OF COGNITIVE IMPAIRMENT AND DEMENTIA: A SYSTEMATIC REVIEW AND META-ANALYSIS OF PROSPECTIVE LONGITUDINAL STUDIES
X.-T. Wang, Z.-T. Wang, H.-Y. Hu, Y. Qu, M. Wang, X.-N. Shen, W. Xu, Q. Dong, L. Tan, J.-T. Yu
J Prev Alz Dis 2021;3(8):277-285
Background: Subjective cognitive decline (SCD) as an early pathological manifestation of brain aging has become more prevalent among older adults.
Objectives: We aimed to investigate the associations of subjective cognitive decline (SCD) with the combined risk of cognitive impairment and dementia.
Design: We performed a systematic review and meta-analysis via searching Embase, PubMed and Cochrane electronic databases from January 1 st 1970 to June 4th, 2020.
Setting: Prospective cohort studies
Participants: Healthy individuals were recruited from community, clinics and population.
Measurements: Healthy individuals with SCD were classified into exposure groups, while those without were considered as the reference group. Adjusted relative risks (RR) were estimated in a random-effects model. Both primary and subgroup analyses were conducted.
Results: Of 28,895 identified studies, 21 studies containing 22 cohorts were eligible for inclusion in the meta-analysis. SCD increased the risk of subsequent cognitive disorders (RR=2.12, 95% confidence intervals [CI] =1.75-2.58, I2=87%, P<0.01). To be specific, SCD conferred a 2.29-fold excess risk for cognitive impairment (RR=2.29, 95% CI=1.66-3.17, I2=83%, P<0.01) and a 2.16-fold excess risk for dementia (RR=2.16, 95% CI=1.63-2.86, I2=81%, P<0.01). In subgroup analyses, participants with SCD in the subgroup of 65-75 years old, long-education (>15 years) subgroup and subgroup of clinics showed a higher risk of developing objective cognitive disorders.
Conclusions: SCD is associated with an increased combined risk of cognitive impairment and incident dementia and should be considered a risk factor for objective cognitive disorders.
X.-T. Wang ; Z.-T. Wang ; H.-Y. Hu ; Y. Qu ; M. Wang ; X.-N. Shen ; W. Xu ; Q. Dong ; L. Tan ; J.-T. Yu (2021): Association of Subjective Cognitive Decline with Risk of Cognitive Impairment and Dementia: A Systematic Review and Meta-Analysis of Prospective Longitudinal Studies. The Journal of Prevention of Alzheimer’s Disease (JPAD). http://dx.doi.org/10.14283/jpad.2021.27