Conversion of mild cognitive impairment to dementia in elderly subjects: a preliminary study in a memory and cognitive disorder unit.

Prevalence and incidence of predementia syndromes vary as a result of different diagnostic criteria, as well as different sampling and assessment procedures. Mild cognitive impairment (MCI) is thought to be a prodromal phase of dementia and therefore highly predictive of subsequent conversion. The aim of our study was to investigate the risk of conversion to dementia for different MCI subtypes diagnosed according to standardized and recently revised criteria (amnestic; impairment of memory plus other cognitive domains; nonamnestic). Participants were recruited among the 2,866 patients referring to the Memory and Cognitive Disorders Unit of the Local Health Unit of Bologna, Maggiore Hospital, between October 2000 and February 2006. In this preliminary study we analyzed data from 52 elderly outpatients with a diagnosis of MCI and a mean follow-up of 1.21+/-0.61 years (range 0.23-3.10 years). Mean age was 72.8+/-6.6 years, males were 61.5%. Mean baseline mini mental state examination (MMSE) score was 27.1+/-1.5. There were 15 incident cases of dementia (28.8%), with Alzheimer's disease (AD) accounting for 53.3% of all cases, AD with cerebrovascular disease for 33.4% and fronto-temporal dementia for 13.3%. Overall rate of conversion was 23.8 per 100 person-years. During the same follow-up period, 53.8% of participants remained stable and 17.3% reverted to normal. Rates of conversion for the specific MCI subtypes were 38 per 100 person-years for amnestic MCI, 20 per 100 person- years for non-amnestic MCI, and 16 per 100 person-years for memory plus other cognitive domains MCI. With respect to non-converters, converters were generally older (76.1+/-4.2 vs. 71.5+/-7.0 years, p=0.021), had a lower MMSE score (26.4+/-1.66 vs. 27.4+/-1.4, p=0.035) and a higher prevalence of atrophy at neuroimaging (73.7% vs. 42.4%, p=0.047). Moreover, with respect to non-converters, converters tended to have higher serum high density lipoprotein (HDL) levels, and lower serum folate levels. No difference was observed for the other study variables, included MCI subtype. Our findings suggest that the current definitions for MCI subtypes, particularly those referring to individuals with multiple or non-amnestic cognitive impairment, include a substantial number of individuals who may not progress to dementia. The possible role of cortical atrophy and low folate in the conversion from MCI to dementia could have important implications, because both conditions are easily identifiable. Moreover, low folate status is potentially amenable to therapeutic options. Although discouraging with respect to the clinical usefulness of currently available MCI criteria, our results raise the possibility that defining a protocol of multiple clinical risk factors may be useful in identifying MCI individuals at increased risk of conversion.

Perception of health-related quality of life and psychological status in oldest hospitalized patients without cognitive impairment.

The most diffuse questionnaires on health-related quality of life (HRQL) and/or psychological status (PS) consider all subjects older than 74 years, for normative reference values, in a single group without any further separation for age decades. Their authors assume that there are no further age-related differences, since older patients had a severely limited autonomy and lose the capacity of grading the severity of the diseases they are affected. Healthy subjects older than 80, without mental impairment (WMI) present an acceptable HRQL, PS and a perception of health status. No data are available on the oldest patients, carrying chronic diseases, admitted to hospital departments for acute health problems.We collected 46 WMI oldest patients (>/= 80 years), admitted for such troubles. They were investigated by the mini mental state examination (MMSE) and, in random order, the Nottingham health profile (NHP) and the psychological general well-being instrument(PGWBI). Clinical data recordings were carried out by the medical personnel, using standardized forms. The value of any individual domain of each patient was compared to the age - (>/=75-year) and sex-matched control group derived from two large Italian population studies, using the Z-score. Charlson's comorbidity index, the index of coexistent disease (ICED), and the cumulative illness rating scale (CIRS) were also calculated. Patients older than 80 did show difference in NHP domains in comparison with normative values only for social isolation, but presented significantly worse Z-scores in all domains ofPGWBI. A relationship was observed between number of daily medications and Z-scores of physical mobility and energy (NHP). Similarly, vitality (PGWBI) correlated with all comorbidity indices, ICED with positive well-being (PGWBI), pain (NHP) with CIRS subscales. Hospitalized WMI oldest subjects maintain a HRQL quite comparable to normative group of subjects older than 74 years. Furthermore, they showed a preserved correct perception of factors/diseases that possibly affect their psychological status and autonomy.

Common polymorphisms in methylenetetrahydrofolate reductase (MTHFR): relationships with plasma homocysteine concentrations and cognitive status in elderly northern italian subjects.

Hyperhomocysteinemia may be a risk factor for cognitive impairment. Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in homocysteine (Hcy) metabolism. Both the MTHFR 677C-->T and the 1298A-->C polymorphisms are associated with mild hyperhomocysteinemia, particularly in conditions of low folate status. The prevalence of these MTHFR polymorphisms and their relationships with plasma total Hcy (tHcy), serum folate and cognitive function was evaluated in 194 elderly Italian individuals: 122 healthy controls (73.8 +/- 7.1 years of age), 24 cognitively- impaired- not-demented individuals (78.6 +/- 9.3 years), and 48 subjects with Alzheimer dementia (AD = 26), vascular dementia (VD =22; 85.5 +/- 7.0 years). Twenty-one percent of all subjects were homozygous for 677C-->T and 7 % for 1298A-->C polymorphism. No significant relationship was found betweenMTHFR polymorphisms and age, cognitive status and type of dementia. Plasma tHcy did not differ significantly by MTHFR genotypes, but, subjects of all genotypes with low serum folate (<12 nmole/l) had higher plasma tHcy (p < 0.001), than subjects with high serum folate (>= 12 nmole/l). The study suggests that 677C-->T and 1298A-->C polymorphisms are common in the Northern Italian population, but do not significantly affect plasma tHcy levels of elderly individuals, even under conditions of low folate status. The lack of association of age and cognitive function with MTHFR genotypes argues against a negative selection for these polymorphisms.

The clock-drawing test in elderly Italian community dwellers: associations with sociodemographic status and risk factors for vascular cognitive impairment.

To evaluate whether performance in the clock-drawing test (CDT) is associated with sociodemographic status and risk factors for cognitive impairment, we examined 744 Italian community dwellers aged > or =65 (73 +/- 6) years scoring > or =24 on the MMSE. CDT was scored by two different methods, the Sunderland and the Wolf-Klein methods. Sociodemographic, lifestyle, clinical and biochemical variables were also recorded. For both scoring methods, lower CDT scores were associated with age, poor education, increased serum C-reactive protein and history of cancer. Associations of lower CDT scores with increased serum glucose and history of cerebrovascular disease were also found for the method with the highest sensitivity to cognitive impairment. This study shows that in elderly community dwellers, CDT may be not totally free from sociodemographic biases, and that it is associated with risk factors for cognitive impairment and frailty.