Table 2.
Characteristics of the included studies
| References | Study design | Sample Mean age (SD) N (Gender) |
Cognitive self-report measures | Outcome(s) examined | Relevant resultsa Covariates |
|---|---|---|---|---|---|
| Reports of Decline | |||||
| Worry vs. No Worry in Global Cognitive Decline | |||||
| van Harten et al.34 | Prospective cohort Median follow-up time 3.9 (IQR 2.6–4.2) years |
Community-based (United States) Median age 79.0 (IQR 75.3–83.6) years N = 1,166 (50.2% women) |
ECog 12-item version (measures self-reported cognitive decline) Are you concerned you have a memory or thinking problem? |
MCI | ECog score indicating self-reported cognitive decline was associated with risk for MCI (HR 2.17 CI [1.51–3.13]). Worry related to the decline was also associated with risk for MCI (HR 1.79 CI [1.24–2.58]). Adjusted for depressive symptoms, anxiety, gender, objective memory performance, physical comorbidities, and ApoE4 carrier status. |
| Worry vs. No Worry in Memory Decline | |||||
| Heser et al.29 | Prospective cohort Nine follow-up waves a (every 1.5 years until follow-up 7, then every ten months) after baseline |
Community-based (Germany) 79.63 (3.5) years N = 2,422 (64.2% women) |
Do you feel like your memory is becoming worse? Yes, but this does not worry me. Yes, this worries me. |
Dementia AD |
SMD without worry was associated with dementia (HR 1.48 CI [1.15–1.91]) and AD (HR 1.63 CI [1.22–2.19]). SMD with worry was associated with dementia (HR 2.48 CI [1.87–3.29]) and AD (HR 2.44 CI [1.73–3.44]). Gender stratified analysis SMD without worry was associated with dementia (HR 1.49 CI [1.16–1.92]) and AD (HR 1.65 CI [1.23–2.21]) in women. SMD with worry was associated with dementia (HR 2.53 CI [1.90–3.36]) and AD (HR 2.43 CI [1.72–3.44]) in women. SMD without worry was not associated with dementia or AD in men. SMD with worry was not associated with dementia but was associated with AD (HR 1.89 CI [1.04–3.42]) in men. Adjusted for depressive symptoms, age, education, and MMSE score. |
| Jessen et al.20 | Prospective cohort Two follow-up waves after baseline (1.5 and 3 years). |
Community-based (Germany) 79.4 (3.4) years N = 2,415 (66.7% women) |
Do you feel like your memory is becoming worse? Yes, but this does not worry me. Yes, this worries me. |
Dementia AD |
SMD without worry was associated with dementia (HR 1.83 CI [1.12–2.99]) and AD (HR 3.04 CI [1.36–6.81]) risk. SMD with worry was also associated with dementia (HR 3.53 CI [2.07–6.03]) and AD (HR 6.54 CI [2.82–15.20]) risk. Adjusted for depressive symptoms, ApoE4 genotype, age, gender, education, and baseline SISCO score. |
| Jessen et al.45 | Prospective cohort Three follow-up waves (one every 18 months) after baseline. |
Community-based (Germany) Participants were age ≥ 75 years N = 1,526 (65.1% women) |
Do you feel like your memory is becoming worse? Yes, but this does not worry me. Yes, this worries me. |
AD | SMD without worry was associated with AD risk (HR 1.88 CI [1.05–3.35]). SMD with worry was associated with AD risk (HR 3.66 CI [2.00–6.70]). Adjusted for age, IADL score, verbal fluency score, delayed recall score, and MMSE score. |
| Koppara et al.46 | Prospective cohort Five follow-up waves (one every 18 months) after baseline. |
Community-based (Germany) 79.58 (3.50) years N = 2,330 (63.9% women) |
Do you feel like your memory is becoming worse? Yes, but this does not worry me. Yes, this worries me. |
Dementia AD |
SMD without worry was associated with dementia (HR 1.41 CI [1.07–1.85]) and AD (HR 1.64 CI [1.16–2.32]) risk. SMD without worry was also associated with dementia (HR 2.63 CI [1.95–3.55]) and AD (HR 2.89 CI [1.96–4.26]) risk. Adjusted for age, gender, education, and depressive symptoms. |
| Snitz et al.32 | Prospective cohort Mean follow-up time 3.09 (SD 2.95) years |
Community-based (United States) 77.27 (7.30) years N = 1,181 (61.2% women) |
16-item composite measure of self-reported memory decline Are you worried about these/this problem(s) with remembering? |
MCI | Self-reported memory decline was not associated with risk for MCI. Self-reported memory decline with worry was associated with risk for MCI (HR 1.66 CI [1.24–2.24]). Adjusted for age, gender, and education. |
| Wolfsgruber et al.22 | Prospective cohort Five follow-up waves (one every 18 months) after baseline. |
Community-based (Germany) 81.1 (3.41) years Baseline (36.9% men) to follow-up one N = 1,990 Follow-up one to follow-up two N = 1,754 Participants categorized by: Inconsistent SMD (report SMD only at baseline or only at follow-up one) Consistent SMD without/with inconsistent worries (SMD at baseline and follow-up one but no or inconsistent worries) Consistent SMD with worries (SMD with worries at baseline and follow-up one) |
Do you feel like your memory is becoming worse? Yes, but this does not worry me. Yes, this worries me. |
AD |
Baseline to follow-up one:
Inconsistent SMD was not associated with AD risk. Consistent SMD without/with inconsistent worries (HR 2.03 CI [1.30–3.15]) and consistent SMD with worries (HR 3.72 CI [2.13–6.50]) were both predictors of AD risk. Follow-up one to follow-up two: Inconsistent SMD was not a risk for AD. Consistent SMD without/with inconsistent worries (HR 2.95 CI [1.31–3.66]) and consistent SMD with worries (HR 3.22 CI [1.70–6.10]) were both predictors of AD. Adjusted for age, education, gender, ApoE4 genotype, and depressive symptoms. |
| Memory Decline vs. Global Cognitive Decline | |||||
| Brodaty et al.47 | Prospective cohort Followed over six years |
Community-based (Australia) 78.1 (4.6) years N = 618 (43.9% men) |
12-item composite measure of self-reported cognitive decline [participants were categorized as mild or severe self-reported cognitive decline based on cut-off score] MAC-Q (six-items; composite measure of self-reported memory decline) |
Dementia | Self-reported cognitive decline was associated with risk for dementia in the participants whose cut-off score put them in the severe category (OR 2.2 CI [0.9–5.0]). Self-reported memory decline was not associated with risk for dementia. Did not report adjusting for covariates |
| Jorm et al.35 | Prospective cohort 3.5-year follow-up (wave 1 to wave 2) |
Community-based (Australia) Age ≥ 70 years at baseline N = 507 (Gender not reported) |
Four-item composite measure of self-reported cognitive decline Four-item composite measure of self-reported memory decline |
Dementia Cognitive decline |
Self-reported cognitive decline and self-reported memory decline were not associated with risk for dementia or cognitive decline. Adjusted for depressive symptoms and anxiety. |
| Slavin et al.31 | Prospective cohort 4-year follow-up (baseline to wave 2) |
Community-based (Australia) 78.0 (4.6) years N = 620 (54.7% women) |
Nine-item composite measure of self-reported cognitive decline 15-item composite measure of self-reported memory decline |
MCI Dementia |
Neither self-reported cognitive decline nor self-reported memory decline predicted risk of MCI or dementia. Adjusted for age, gender, education, and the openness scale of the NEO-FFI. |
| Memory Decline vs. Executive Function Decline | |||||
| Sacuiu et al.48 | Prospective cohort Two follow-up waves after baseline (5 years, 9 years). Followed-up for dementia diagnosis until year 12. |
Community-based and residential care-based (Sweden) 73.8 (5.2) years (no subjective memory/cognitive decline) 74.9 (5.7) years (subjective memory/cognitive decline) N = 921 (75.7% women) |
CPRS – data grouped into memory decline and executive function decline domains. Executive function decline domain contained three subdomains: concentration; making decisions; taking initiative. | Dementia | Self-reported memory decline was associated with risk for dementia (HR 1.9 CI [1.3–2.7]). Executive function decline (with all subdomains) was associated with risk for dementia (HR 1.6 CI [1.2–2.3]). The concentration subdomain was associated with risk for dementia (HR 1.9 CI [1.2–3.1]). The making decisions and taking initiative subdomains were not associated with risk for dementia. Adjusted for age, gender, and depressive symptoms. |
| Daily Function Affected vs. Not Affected in Memory Decline | |||||
| Sargent-Cox et al.21 | Prospective cohort Two follow-up waves after baseline |
Community-based (Australia) 62.52 (1.51) years N = 2,082 (49.0% women) |
Participants were asked if they could remember things as well as they used to in their earlier life. If they answered yes or depends/sometimes then they were asked whether their memory problem interfered with their daily life. |
MCI CDR scale impairment MCD Cognitive decline |
Self-reported memory decline was associated with a decreased risk for impairment on the CDR scale [OR 0.22 CI (0.05 – 0.92)]. Self-reported memory decline that affected daily functioning was associated with an increased risk for MCI [OR 3.54 CI (1.19–10.48)] but no other outcomes. Adjusted for age, gender, education, diabetes, hypertension, smoking status, alcohol use, and depressive symptoms. |
| Reports of Current Cognitive Performance | |||||
| Memory vs. Global Cognition | |||||
| Sohrabi et al.33 | Prospective cohort Two follow-up waves (at least 12 months apart) after baseline over a period of three years |
Community-based (Australia) 64.59 (7.83) years N = 209 (67.9% women) |
MFQ (composite measure of self-reported cognitive problems) Do you have any difficulty with your memory? |
Cognitive decline | Neither self-reported cognitive problems nor self-reported memory decline were associated with risk for cognitive decline. Adjusted for depressive symptoms. |
| Memory vs. Peer Comparisons | |||||
| Abner et al.49 | RCT that transitioned to a prospective cohort study Mean follow-up time 5.7 (SD 2.8) years |
Community-based (Canada, United States [includes Puerto Rico]) 67.5 (5.3) years N = 7,547 men |
Have you noticed any changes in your memory? Do you feel that you have more problems with your memory than most people? |
Dementia | Self-reported memory decline (HR 1.87 CI [1.47–2.38]) and peer comparison of self-reported memory decline (HR 6.01 CI [3.68–9.74]) were both predictive of dementia risk. Adjusted for age, education, race, ApoE4 genotype, history of head injury, diabetes, hypertension, and sleep apnea. Subanalysis with Black participants Self-reported memory decline at baseline: Self-reported memory decline (HR 2.46 CI [1.15–5.27]) and peer comparison of self-reported memory decline (HR 35.7 CI [12.99–100]) were associated with risk for dementia. No self-reported memory decline at baseline: Self-reported memory decline (HR 1.81 CI [1.41–2.33]) and peer comparison of self-reported memory decline (HR 4.5 CI [2.55–7.94]) were associated with risk for dementia. |
| Memory vs. Peer Perceptions | |||||
| Ronnlund et al.36 | Prospective cohort Followed for 10–12 years after baseline |
Community-based (Sweden) 71.5 (8.8) years N = 1,547 (unable to determine gender distribution of reported sample) Used a full sample and five+ years to dementia diagnosis sample (participants had a 5+ year survival time to dementia diagnosis) |
PRMQ (composite measure of self-reported memory problems) Does anyone close to you (family, friends) think that you have a poor memory? (grouped into never, rarely, sometimes and often for analysis) |
Dementia AD |
Full sample PRMQ was associated with risk for dementia (HR 1.18 CI [1.04–1.34]) and AD (HR 1.22 CI [1.04–1.43]) but not when peer perceptions of memory was added to the model. Self-reported memory problems by others predicted both dementia (Rarely HR 1.65 CI [1.11–2.45]; Sometimes HR 2.04 CI [1.38–3.00]; Often HR 2.98 CI [1.60–5.54]) and AD (Rarely HR 1.78 CI [1.07–2.97]; Sometimes HR 2.06 CI [1.24–3.42]; Often HR 3.86 CI [1.79–8.35]). Five+ years to dementia diagnosis sample PRMQ was associated with risk for dementia only (HR1.23 CI [1.02–1.49]) but not AD. When peer perceptions of memory problems was added to the model, PRMQ was no longer predictive of dementia. Self-reported memory problems by others predicted both dementia (Rarely NS; Sometimes HR 1.76 CI [1.01–3.05]; Often HR 2.93 CI [1.15–7.47]) and AD (Rarely NS; Sometimes HR 2.24 CI [1.02–4.94]; Often HR 4.89 CI [1.36–17.60]). Adjusted for age, gender, marital status, education, and depressive symptoms. |
| Global Cognition vs. Peer Perceptions | |||||
| Tomata et al.50 | Prospective cohort Follow-up period over 5.7 years |
Community-based (Japan) 73.8 (5.9) years N = 13,974 (55.1% women) |
Do you find yourself no knowing today’s date? Do you make a call by looking up phone numbers? Do your family and friends point out your memory loss? |
Dementia | Not knowing the current date (HR 2.11 CI [1.88–2.37]), having to look up phone numbers (HR 2.15 CI [1.84–2.51]), and peer perceptions of memory problems (HR 2.32 CI [2.06–2.60]) were all associated with risk for dementia. Endorsing one (HR 1.89 CI [1.65–2.15]), two (HR 3.01 CI [2.59–3.50]), or all three (HR 6.20 CI [4.87–7.90]) of the self-reported items was associated with increased risk for dementia. Adjusted for age and gender. |
| Daily Function Affected vs. Not Affected in Current Memory Performance | |||||
| Chary et al.30 | Prospective cohort study Twenty-year timeline (for this paper, analyzed in three- or ten-year windows) |
Community-based (France) 74.7 (6.4) years N = 2,882 (unable to determine gender distribution of reported sample) |
Do you frequently have difficulties in retaining or remembering new simple information? Do you frequently have difficulties in retrieving or remembering old memories? Do you frequently have difficulties in finding words (naming objects and so forth)? Do you frequently have forgetfulness in activities of daily living (shopping list, in using household items, and so forth)? |
Dementia |
Three-year window Low education level: Neither self-reported memory problems nor self-reported memory problems that affect daily function were predictive of dementia. High education level: Difficulty in retaining or remembering new information (OR 2.5 CI (1.74–3.59]), difficulty in retrieving or remembering old memories (OR 1.32 CI [0.51–3.41]), difficulty finding words (OR 1.46 CI [1.02–2.09]) and self-reported memory problems that affected daily function (OR 1.35 CI [0.94–1.94]) were all predictive of dementia. Ten-year window Low education level: Neither self-reported memory problems nor self-reported memory problems that affect daily function were predictive of dementia. High education level: Difficulty in retaining or remembering new information (OR 1.47 CI [1.12–1.93]), difficulty finding words (OR 1.18 CI [0.91–1.53]), and self-reported memory problems that affected daily function (OR 1.47 CI [1.13–1.91]), were all risks for developing dementia. Difficulty in retrieving or remembering old memories was not a risk for developing dementia. Adjusted for age, IADLs, IST, BVRT, DSST, and MMSE |
| Reports of Decline vs. Current Cognitive Performance | |||||
| Memory Decline vs. Current Memory Performance | |||||
| Jungwirth et al.52 | Prospective cohort Two follow-up waves (every 2.5 years) after baseline |
Community-based (Austria) 75.8 (0.04) years N = 487 (65.0% women) |
Four-item composite measure of self-reported memory decline. Do you have any complaints about your memory? |
AD | Self-reported memory decline was associated with risk for AD (OR 1.68 CI [1.34–2.10]). Self-reported memory problems were also associated with risk for AD (OR 3.00 CI [1.07–5.37]). |
| Memory Decline vs. Peer Perceptions | |||||
| Ronnlund et al.51 | Prospective cohort Varying waves were baseline depending on sample. Follow-up time ranged from 5–17 years. |
Community-based (Sweden) Age ≥ 60 years at baseline N = 2,043 (Unable to determine gender distribution of reported sample) Used a full sample and a five+ years to dementia diagnosis sample (participants had a 5+ year survival time to dementia diagnosis) |
How do you perceive your memory today compared with five years ago? (grouped into better/same [reference], worse, much worse) Does anyone close to you (family, friends) think that you have a poor memory? (grouped into never [reference], rarely, occasionally and often/usually for analysis) |
Dementia AD |
Full sample Self-reported memory decline predicted both dementia (Worse HR 1.48 CI [1.19–1.85]; Much worse HR 1.66 CI [1.06–2.60]) and AD (Worse HR 1.51 CI [1.12–2.03]; Much worse HR 1.94 CI [1.09–3.44]) risk. Peer perceptions of memory problems predicted both dementia (Rarely HR 1.38 CI [1.05–1.80]; Occasionally HR 1.50 CI [1.15–1.96]; Often/Usually HR 4.04 CI [2.54–6.45]) and AD (Rarely HR 1.56 CI [1.08–2.23]; Occasionally HR 1.91 CI [1.34–2.72]; Often/Usually HR 5.92 CI [3.17–11.07]) risk. Five+ years to dementia diagnosis sample (only analyzed for dementia prediction and did not report all response groupings) Self-reported memory decline with a “worse” response predicted dementia risk (HR 1.33 CI [1.02–1.73]). Peer perceptions of memory problems with response “often/usually” was associated with dementia risk (HR 3.62 CI [2.01–6.54]). Adjusted for age, gender, education, cardiovascular risk factors, depressive symptoms, and episodic memory score. |
| Memory Decline vs. Peer Comparisons | |||||
| Ronnlund et al.51 | Prospective cohort Varying waves were baseline depending on sample. Follow-up time ranged from 5–17 years. |
Community-based (Sweden) Age ≥ 60 years at baseline N = 2,043 (Unable to determine gender distribution of reported sample) Used a full sample and a five+ years to dementia diagnosis sample (participants had a 5+ year survival time to dementia diagnosis) |
How do you perceive your memory today compared with five years ago? (grouped into better/same [reference], worse, much worse) How do you perceive your memory in comparison with that of others of your age? (grouped into better, same [reference], and worse/much worse) |
Dementia AD |
Full sample Self-reported memory decline in comparison to five years ago predicted both dementia (Worse HR 1.48 CI [1.19–1.85]; Much worse HR 1.66 CI [1.06–2.60]) and AD (Worse HR 1.51 CI [1.12–2.03]; Much worse HR 1.94 CI [1.09–3.44]) risk. Peer comparison of self-reported memory decline with a response of “worse/much worse” predicted both dementia (HR 1.92 CI [0.86–1.40]) and AD (HR 2.54 CI [1.72–3.74]) risk. Five+ years to dementia diagnosis sample (only analyzed for dementia prediction and did not report all response groupings) Self-reported memory decline in comparison to five years ago with a “worse” response predicted dementia risk (HR 1.33 CI [1.02–1.73]). Peer comparison of self-reported memory decline with a response of “worse/much worse” predicted dementia risk (HR 2.03 CI [1.38–2.98]). Adjusted for age, gender, education, cardiovascular risk factors, depressive symptoms, and episodic memory score. |
Note. AD = Alzheimer’s disease; BVRT = Benton Visual Retention Test; CDR = Clinical Dementia Rating; CI = 95% confidence interval; CPRS = Comprehensive Psychopathological Rating Scale; DSST = Digit Symbol Substitution Test; ECog = Everyday Cognition Scale; HR = hazard ratio; IADL = Independent Activities of Daily Living; IQR = interquartile range; IST = Isaacs Set Test; MAC-Q = Memory Assessment Clinic Questionnaire; MCD = mild cognitive disorder; MCI = mild cognitive impairment; MFQ = Memory Functioning Questionnaire; MMSE = Mini-Mental State Examination; NEO-FFI = NEO – Five Factor Inventory; NS = not significant; OR = odds ratio; PRMQ = Prospective and Retrospective Memory Questionnaire; RCT = randomized controlled trial; SISCO = Structured Interview for Diagnosis of Dementia of Alzheimer Type, Multi-infarct Dementia and Dementia of Other Etiology According to DSM-IV and ICD-10 Cognitive score; SD = standard deviation; SMD = self-reported memory decline
a
All results are reported from the final adjusted model unless otherwise indicated
b
Cognitive self-report items were measured in separate analyses
c
Assigned to two different categories