Prevalence of DSM-5 Mild Neurocognitive Disorder in Dementia-Free Older Adults: Results of the Population-Based LIFE-Adult-Study.
OBJECTIVE
The DSM-5 introduces mild neurocognitive disorder (miNCD) as a syndrome that recognizes the potential clinical importance of acquired cognitive deficits being too mild to qualify for diagnosis of dementia. We provide new empirical data on miNCD including total, age-, and sex-specific prevalence rates; number and types of neurocognitive domains being impaired; and diagnostic overlap with the well-established mild cognitive impairment (MCI) concept.


METHODS
Cross-sectional results of an observational cohort study (LIFE-Adult-Study).


METHODS
General population.


METHODS
A total of 1,080 dementia-free individuals, aged 60-79 years.


METHODS
We calculated weighted point prevalence rates with confidence intervals (95% CI) for miNCD and analyzed diagnostic overlap between miNCD and MCI by calculating overall percentage agreement and Cohen's kappa coefficient.


RESULTS
Weighted total prevalence of miNCD was 20.3% (95% CI: 17.8-23.0). Prevalence was similar in both sexes, but significantly higher in older age. Two-thirds (66.2%) of the individuals with miNCD showed impairment restricted to only one out of six possible neurocognitive domains. Learning and memory was the most frequently (38.3%) impaired domain in all miNCD-cases, followed by social cognition (26.1%). Analysis of diagnostic overlap with MCI yielded an overall agreement of 98.6% and a kappa of 0.959.


CONCLUSIONS
By considering all six predefined neurocognitive domains, our study observed a substantial proportion of dementia-free older adults having miNCD. Provision of information on the underlying etiology/ies may be of prime importance in future studies aiming at evaluating the clinical relevance of the miNCD syndrome.
Institute of Social Medicine, Occupational Health and Public Health, University of Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany. Electronic address: tobias.luck@medizin.uni-leipzig.de.
Tobias
T
Luck
Institute of Social Medicine, Occupational Health and Public Health, University of Leipzig, Leipzig, Germany; LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany.
Francisca S
FS
Then
Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Day Clinic for Cognitive Neurology, University Hospital Leipzig, Leipzig, Germany.
Matthias L
ML
Schroeter
Collaborative Research Centre 1052 "Obesity Mechanisms", University of Leipzig, Leipzig, Germany; Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
Veronica
V
Witte
Institute for Medical Informatics, Statistics and Epidemiology, University of Leipzig, Leipzig, Germany.
Christoph
C
Engel
Institute for Medical Informatics, Statistics and Epidemiology, University of Leipzig, Leipzig, Germany.
Markus
M
Loeffler
Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Leipzig, Germany.
Joachim
J
Thiery
Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Day Clinic for Cognitive Neurology, University Hospital Leipzig, Leipzig, Germany.
Arno
A
Villringer
Institute of Social Medicine, Occupational Health and Public Health, University of Leipzig, Leipzig, Germany.
Steffi G
SG
Riedel-Heller
D000368:Aged; D060825:Cognitive Dysfunction / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence
dementia; diagnostic and statistical manual of mental disorders (DSM-5); mild cognitive impairment; mild neurocognitive disorder; prevalence