Risk Of Progression To Dementia Research Articles

Different aspects of failing to recover from proactive semantic interference predicts rate of progression from amnestic mild cognitive impairment to dementia.

This study investigated the role of proactive semantic interference (frPSI) in predicting the progression of amnestic Mild Cognitive Impairment (aMCI) to dementia, taking into account various cognitive and biological factors. The research involved 89 older adults with aMCI who underwent baseline assessments, including amyloid PET and MRI scans, and were followed longitudinally over a period ranging from 12 to 55 months (average 26.05 months). The findings revealed that more than 30% of the participants diagnosed with aMCI progressed to dementia during the observation period. Using Cox Proportional Hazards modeling and adjusting for demographic factors, global cognitive function, hippocampal volume, and amyloid positivity, two distinct aspects of frPSI were identified as significant predictors of a faster decline to dementia. These aspects were fewer correct responses on a frPSI trial and a higher number of semantic intrusion errors on the same trial, with 29.5% and 31.6 % increases in the likelihood of more rapid progression to dementia, respectively. These findings after adjustment for demographic and biological markers of Alzheimer's Disease, suggest that assessing frPSI may offer valuable insights into the risk of dementia progression in individuals with aMCI.

Commentary on: Amnestic mild cognitive impairment and incident dementia and Alzheimer's disease in geriatric depression.

In this month's “Paper of the Month,” Steffens and colleagues (Steffens et al., 2014) report on the relationship between depression, mild cognitive impairment (MCI) and future risk of progression to dementia. It has long been known that there is a complex relationship between depression and cognitive impairment, with depression common in those with cognitive impairment and dementia, and subsequent cognitive decline frequent in patients with depression (Wallin et al., 2013). This relationship has often been difficult to study, not least because definitions have often been mutually exclusive. For example, many studies of MCI have excluded patients with depression. This is not unreasonable to increase diagnostic certainty and obtain a more “pure” group of those with MCI who are likely to progress to Alzheimer's disease, but of course at the same time limits the ability to determine interactions between MCI and depression. On the other hand, it is known that non-cognitive symptoms, most particularly depression, frequently occur in those with MCI and have been shown to increase the risk of likely future decline.

Mild Cognitive Impairment

Mild cognitive impairment (MCI) describes a state of cognitive functioning that is below defined norms, yet falls short of dementia in severity. It exists across a cognitive continuum with borders that are difficult to define precisely. Within our "graying" western societies, its prevalence increases with age. A number of subtypes of MCI, including age-associated memory impairment (AAMI), age-associated cognitive decline (AACD), amnestic MCI (MCIa), and cognitive impairment not dementia (CIND) have contributed to our understanding of MCI. Recent efforts have been directed at developing a uniform diagnostic classification for MCI that reflects the maturation of knowledge about this state. There is considerable etiological and clinical heterogeneity within MCI; however, there is a unifying increased risk of progression to dementia. The diagnostic process for MCI involves assessment of multiple cognitive domains, with particular attention to episodic and semantic memory, while neuroimaging with structural MRI and PET both add to the diagnostic and prognostic evaluation of MCI. Although there are no pharmacological treatments at present that are capable of delaying the long-term progression of MCI to dementia, there is some evidence of short-term symptomatic benefits with acetylcholinesterase inhibitors. MCI is an important clinical problem, which clinicians can expect to face with increasing frequency. The essentials of management include a thorough assessment directed at etiological determination and counseling and judicious use of available therapeutics.