of depressive symptoms, and prior cognitive performance (Dufouil et al. 2005 ). In
the neuroimaging substudy of the Baltimore Longitudinal Study of Aging, which
involved 98 adults between the ages of 53 and 83, total SMC as assessed by the
Cognitive Failures Questionnaire (CFQ; Broadbent et al. 1982 ) were associated
with decline in verbal learning and delayed verbal recall over an 11-year follow-up,
after controlling for depression (Hohman et al. 2011 ). Finally, in the ACTIVE trial
described above, although baseline SMC were unrelated to change in objective
cognitive performance,changes in the Frequency of Forgetting subscale were
associated with changes in objective memory over time, after controlling for age,
education, sex, race, depressive symptoms, and health status (Parisi et al. 2011 ).
Interestingly, no relationship was found between changes in the Mnemonics Usage
subscale and objective memory performance, or changes in performance over time,
suggesting specificity in types of SMC.
SMC and Decline from Prior Levels of Function
Studies provide mixed evidence regarding the possibility that SMC may reflect
decline from prior levels of function. In the Mayo Older Americans Normative
Studies (MOANS) cohort (Ivnik et al. 1992 ), current SMC in 281 adults aged 57–
93 years, as assessed by the Frequency of Forgetting or Seriousness of Forgetting
subscales of the MFQ, were not associated with change in verbal comprehension,
perceptual organization, attention concentration, learning, and retention from
3.7 years earlier (Smith et al. 1996 ). In the Jorm et al. ( 1997 ) study detailed above,
SMC were unrelated to decline in global cognition, processing speed, or episodic
memory from 3 years earlier, after controlling for anxiety and depression.
Similarly, a study of 229 older adults (aged 65–98 years) found SMC, assessed by a
single question about memory problems in relation to most other people, were not
associated with decreases in memory performance from 5 years prior (Frerichs and
Tuokko 2006 ).
In contrast, other studies report that SMC do reflect a decline from prior levels of
cognitive function. A study of 80 community-dwelling older adults (average age
- found that new SMC, assessed by a single question about the presence of
memory problems, were associated with a significant decline in both verbal and
nonverbal memory from 1 year prior, when SMC were denied in response to that
same question (Schofield et al.1997b). In the EVA study discussed above, SMC at
4-year follow-up were associated with decline in processing speed and verbal
memory from baseline, independent of depressive symptoms (Dufouil et al. 2005 ).
Finally, in the Wang et al. ( 2004 ) study discussed above, new SMC at follow-up
were associated with decline in overall cognition and verbal recall from evaluation
5 years earlier (Wang et al. 2004 ).
290 M.T. Weber and P.M. Maki