From mild cognitive impairment to dementia: a prevalence study in a district of Tuscany, Italy.

OBJECTIVE: A door-to-door two-phase study was designed in order to estimate the prevalence of cognitive deficit amongst the residents of a district in Tuscany (central Italy). Identification of cases with mild cognitive impairment (MCI) was given high priority, because this condition has been suggested as a term for the boundary area between normal aging and dementia. METHODS: Of the 1600 subjects who completed the screening phase, 354 scored under the cut-off point of the Mini Mental State Examination and Clinical Dementia Rating and were investigated by means of a standardized diagnostic protocol. RESULTS: The prevalence of MCI and age-related cognitive decline was 4.9 and 9.3%, respectively; low levels of education significantly increased the risk of these conditions. The prevalence of dementia over age 65 was 6.2%, with a significant risk association with age. In our population, Alzheimer's disease was the most frequent type of dementia (prevalence rate 4.2%) and increased risk depending on age, sex and education has been found. CONCLUSIONS: Our findings are somewhat similar to previous studies. Further epidemiological and longitudinal studies are warranted to identify which diagnostic category is more predictive for dementia.

Oxidative DNA damage in peripheral leukocytes of mild cognitive impairment and AD patients.

It is well established that oxidative stress plays a key role in the degenerative neuronal death and progression of Alzheimer's disease (AD), although it is not clear if it is the primary triggering event in the pathogenesis of this disorder. Mild cognitive impairment (MCI) is a clinical condition between normal aging and AD, characterized by a memory deficit without loss of general cognitive and functional abilities. We performed this study by a comet assay analysis to evaluate the level of primary and oxidative DNA damage in two groups of MCI and AD patients, compared to healthy controls. Data showed a significantly higher level of primary DNA damage in leukocytes of AD and also of MCI patients compared to control individuals (average: 2.09+/-0.79 and 2.47+/-1.01, respectively for AD and MCI, versus 1.04+/-0.31 in controls). Moreover, the amount of oxidised DNA bases (both purines and pyrimidines) was significatively higher in the two groups of patients (AD and MCI) compared to controls. Our results give a further indication that oxidative stress, at least at the DNA level, is an earlier event in the pathogenesis of AD.

Lormetazepam effects on daytime vigilance, psychomotor performance and simulated driving in young adult healthy volunteers.

OBJECTIVE: To assess the residual effects of lormetazepam on daytime vigilance, psychomotor performance and simulated driving in adult healthy volunteers. MATERIAL: Twelve subjects (7 women, 5 men), aged 27 - 38 years (mean 31). METHOD: Subjects received lormetazepam 1 mg tablet and placebo for 3 days at nighttime in a randomized, double-blind, crossover design, with a 1-week interval between medications. On the morning following the last drug administration, the subjects completed a 15-min battery of neuropsychological tests aimed at assessing memory and attention, performed simple and choice visual reaction times, and self-rated their own level of sleepiness using the Epworth sleepiness scale. Afterwards, an interactive, computer-based driving simulator (STISIM) was used to assess the effect of the study drugs on driving ability, followed by the multiple sleep latency test (MSLT). RESULTS: The findings showed that participants had similar performance when treated with lormetazepam and placebo. Indeed, as compared with baseline, neuropsychological tests, visual reaction times, sleep latency using the MSLT and driving ability showed no deterioration following either placebo or active medication. CONCLUSIONS: The data suggest that 3-day use of lormetazepam 1 mg/day neither influences daytime vigilance nor impairs psychomotor task performance and simulated driving. Results confirm previous evidence that the intermediate-acting hypnotic benzodiazepine lormetazepam is devoid of residual effects in respect to psychomotor ability. However, caution should be exercised in the interpretation of the results due to the limited sensitivity of the study.