Incidence of Dementia in Mild Cognitive Impairment in the Cardiovascular Health Study Cognition Study

Abstract

Subjects: There were 136 subjects with MCI. Mild cognitive impairment was subclassified as MCI amnestic type and MCI multiple cognitive deficits type (MCI-MCDT); subjects with MCI-MCDT were also grouped based on the presence of a memory impairment. Subjects with MCI were classified as possible when there were comorbidities that could explain the subjects' cognitive deficits and as probable when there were none.Main Outcome Measure: Dementia. Results:The incidence of all dementias in the subjects with MCI was 147 per 1000 person-years (mean follow-up overall, 4.3 years). Of the 136 subjects with MCI, 69 (51%) in 1998 through 1999 progressed to dementia (57 [83%] to Alzheimer disease [AD]), but 25 (18%) returned to normal. Of the 10 subjects with probable MCI amnestic type, 7 (70%) progressed to dementia (all of them to AD) and none returned to normal, whereas 7 (41%) of the 17 subjects with possible MCI amnestic type became demented (6 [86%] to AD) and 3 (18%) returned to normal. Of the 40 subjects with probable MCI-MCDT, 21 (52%) progressed to dementia (17 [81%] to AD) and 2 (5%) returned to normal. Of the 69 subjects with possible MCI-MCDT, 34 (49%) progressed to dementia (28 [82%] to AD) and 20 (29%) returned to normal. Among the subjects with probable MCI-MCDT, 15 (54%) of 28 with and 6 (50%) of 12 without memory deficits progressed to dementia.Conclusions: Subjects with MCI are at high risk for dementia. The probable MCI diagnosis identified individuals in the earliest stages of dementia, usually AD, whereas the possible MCI diagnosis identified a more heterogeneous group. However, this latter group had only a slightly lower rate of conversion to dementia than the group with probable MCI, suggesting that even with comorbid conditions, there is a high likelihood of the presence of a progressive dementing disorder.

Changes in Montreal Cognitive Assessment Scores Over Time

“…Using this metric, approximately a fourth of MCI participants (~13/53) exhibited reliable decline over the 3.5-year period. This is in keeping with prior findings suggesting that MCI is a heterogeneous syndrome showing diverse trajectories, with some patients declining while others remain stable or even improving over time (Ganguli, Dodge, Shen, & DeKosky, 2004; Lopez et al, 2007). However, these findings may also be related to study sample bias and lack of diagnostic clarification at baseline, which is elaborated below.…”

Changes in Montreal Cognitive Assessment Scores Over Time

“…Using this metric, approximately a fourth of MCI participants (~13/53) exhibited reliable decline over the 3.5-year period. This is in keeping with prior findings suggesting that MCI is a heterogeneous syndrome showing diverse trajectories, with some patients declining while others remain stable or even improving over time (Ganguli, Dodge, Shen, & DeKosky, 2004; Lopez et al, 2007). However, these findings may also be related to study sample bias and lack of diagnostic clarification at baseline, which is elaborated below.…”

Effect of intensive blood pressure control on subtypes of mild cognitive impairment and risk of progression from SPRINT study

“…Our findings are consistent with prior studies showing that amnestic and multi‐domain MCI are the most prevalent subtypes in persons being assessed for cognitive decline 30–32 . In the longitudinal Sydney Memory and Aging Study, 84% of participants who were diagnosed with incident dementia were previously diagnosed with MCI, most commonly the amnestic and multi‐domain subtypes 24 .…”

The validity of amnestic MCI and non-amnestic MCI at age 75 in the prediction of Alzheimer's dementia and vascular dementia

“…Manly et al presented a relative risk for developing AD between 3.2 and 4.3 for aMCI (single and multiple) and between 0.7 and 1.9 for naMCI (single and multiple). Lopez et al (2007), after a mean follow-up period of only 4.3 years, found a conversion rate of aMCI to AD of 48.1%, which is comparable to our results. The conversion rate of MCI multiple cognitive domain type to AD was 41.3% and higher than that in our study.…”

Changes in Montreal Cognitive Assessment Scores Over Time

“…Using this metric, approximately a fourth of MCI participants (~13/53) exhibited reliable decline over the 3.5-year period. This is in keeping with prior findings suggesting that MCI is a heterogeneous syndrome showing diverse trajectories, with some patients declining while others remain stable or even improving over time (Ganguli, Dodge, Shen, & DeKosky, 2004; Lopez et al, 2007). However, these findings may also be related to study sample bias and lack of diagnostic clarification at baseline, which is elaborated below.…”

Effect of intensive blood pressure control on subtypes of mild cognitive impairment and risk of progression from SPRINT study

“…Our findings are consistent with prior studies showing that amnestic and multi‐domain MCI are the most prevalent subtypes in persons being assessed for cognitive decline 30–32 . In the longitudinal Sydney Memory and Aging Study, 84% of participants who were diagnosed with incident dementia were previously diagnosed with MCI, most commonly the amnestic and multi‐domain subtypes 24 .…”

The validity of amnestic MCI and non-amnestic MCI at age 75 in the prediction of Alzheimer's dementia and vascular dementia

“…Manly et al presented a relative risk for developing AD between 3.2 and 4.3 for aMCI (single and multiple) and between 0.7 and 1.9 for naMCI (single and multiple). Lopez et al (2007), after a mean follow-up period of only 4.3 years, found a conversion rate of aMCI to AD of 48.1%, which is comparable to our results. The conversion rate of MCI multiple cognitive domain type to AD was 41.3% and higher than that in our study.…”

Changes in Montreal Cognitive Assessment Scores Over Time

“…Using this metric, approximately a fourth of MCI participants (~13/53) exhibited reliable decline over the 3.5-year period. This is in keeping with prior findings suggesting that MCI is a heterogeneous syndrome showing diverse trajectories, with some patients declining while others remain stable or even improving over time (Ganguli, Dodge, Shen, & DeKosky, 2004; Lopez et al, 2007). However, these findings may also be related to study sample bias and lack of diagnostic clarification at baseline, which is elaborated below.…”

Effect of intensive blood pressure control on subtypes of mild cognitive impairment and risk of progression from SPRINT study

“…Our findings are consistent with prior studies showing that amnestic and multi‐domain MCI are the most prevalent subtypes in persons being assessed for cognitive decline 30–32 . In the longitudinal Sydney Memory and Aging Study, 84% of participants who were diagnosed with incident dementia were previously diagnosed with MCI, most commonly the amnestic and multi‐domain subtypes 24 .…”

The validity of amnestic MCI and non-amnestic MCI at age 75 in the prediction of Alzheimer's dementia and vascular dementia

“…Manly et al presented a relative risk for developing AD between 3.2 and 4.3 for aMCI (single and multiple) and between 0.7 and 1.9 for naMCI (single and multiple). Lopez et al (2007), after a mean follow-up period of only 4.3 years, found a conversion rate of aMCI to AD of 48.1%, which is comparable to our results. The conversion rate of MCI multiple cognitive domain type to AD was 41.3% and higher than that in our study.…”