المفاهيم الأساسية
Limbic-predominant amnestic neurodegenerative syndrome (LANS) is a newly recognized memory condition that is distinct from Alzheimer's disease and primarily affects the limbic system, leading to a slow, amnestic, and predominantly neurodegenerative syndrome.
الملخص
The article discusses a newly recognized memory condition called limbic-predominant amnestic neurodegenerative syndrome (LANS), which is distinct from Alzheimer's disease. LANS is characterized by a slow, amnestic, and predominantly neurodegenerative syndrome that primarily affects the limbic system.
The key highlights and insights from the article are:
LANS is a different type of neurodegenerative syndrome that progresses slowly, is limited mainly to memory loss, and affects only the limbic system, as opposed to Alzheimer's disease, which involves neocortical degeneration.
The clinical criteria for LANS include core features (slow, amnestic, predominant neurodegenerative syndrome), standard supportive features (older age, mild clinical syndrome, hippocampal atrophy out of proportion to syndrome severity, mildly impaired semantic memory), and advanced supportive features (limbic hypometabolism, low likelihood of significant neocortical tau pathology).
LANS is highly associated with limbic-predominant, age-related TDP-43 encephalopathy neuropathological change (LATE-NC), for which no biomarkers are yet available.
The diagnosis of LANS requires a nuanced assessment of the pattern of cognitive deficits, brain imaging, and disease progression over time, which may involve referral to specialists like behavioral neurologists, geriatricians, or psychiatrists.
Primary care physicians can use various cognitive assessments, such as the Montreal Cognitive Assessment (MoCA), to help diagnose dementias and identify potential LANS cases, and should also look for reversible causes of memory complaints.
As awareness of LANS increases, the proportion of people diagnosed with this condition may rise, and further research is needed to develop better diagnostic tools and treatments.
الإحصائيات
LANS is found in about 40% of autopsied brains in people over the age of 85 years.
A diagnosis of mild cognitive impairment or mild amnestic dementia (i.e., a score of ≤ 4 on the Clinical Dementia Rating Sum of Boxes [CDR-SB]) is a standard supportive feature for LANS.
Hippocampal volume is smaller than expected on MRI compared with the CDR-SB score in LANS patients.
اقتباسات
"Memory problems are not always Alzheimer's disease. It's important to broaden the differential diagnosis and seek diagnostic clarity and precision for patients who experience problems with brain functioning later in life."
"We are increasingly recognizing that the syndrome of dementia in older adults is heterogeneous."
"It may be that as we start more freely giving the diagnosis of a possible LANS, the proportion of people will go up."