The use of a simple, safe, and easy to perform assessment tool, like gait speed, to evaluate vulnerability to adverse outcomes in community-dwelling older people is appealing, but its predictive capacity is still questioned. The present manuscript summarises the conclusions of an expert panel in the domain of physical performance measures and frailty in older people, who reviewed and discussed the existing literature in a 2-day meeting held in Toulouse, France on March 12–13, 2009. The aim of the IANA Task Force was to state if, in the light of actual scientific evidence, gait speed assessed at usual pace had the capacity to identify community-dwelling older people at risk of adverse outcomes, and if gait speed could be used as a single-item tool instead of more comprehensive but more time-consuming assessment instruments.

Objective: Vitamin D has been shown to have multiple biological targets mediated by the vitamin D receptor present in many cells. Specific actions on the central nervous system (CNS) have been described. The objective of this review was to describe the relationship between vitamin D and the nervous system throughout the different stages of life. Methods: A bibliographical search was performed in the MedLine and Cochrane library databases. The keywords used were: ‘vitamin D’ and ‘nervous system’ and/or ‘central nervous system’ and/or ‘nervous system diseases’ and/or ‘psychological tests’ and/or ‘neuropsychological tests’ and/or ‘mental disorders’. The search period ranged from 01/01/1988 to 31/10/2009. Two hundred and ninety-five abstracts were first identified after screening. A final selection of 127 articles was used for the purpose of this review. Results: The studies published over the past 20 years provide an increasing number of arguments in favor of a life-long role of vitamin D on the nervous system as a whole, and in particular on the CNS. During cerebral development, vitamin D may act like a neurosteroid hormone in the areas of neurotransmission, neuroprotection, and neuroimmunomodulation. Moreover, vitamin D deficiency has been associated with neurological and psychiatric disorders. In older adults, hypovitaminosis D has been associated with neuromuscular disorders, dementia, and Parkinson’s disease. Thus, vitamin D supplementation might have a protective effect against these neurological disorders. Conclusions: Vitamin D has been associated with many neurological functions and its deficiency with dysfunction. Low serum 25-hydroxyvitamin D concentrations can potentially be reversed. This simple and low-cost correction might contribute to the primo-secondary prevention of various neuropsychiatric disorders.

Background/Aims: Gait speed is cross-sectionally associated with attention and psychomotor speed in older community dwellers. It is unclear if gait speed predicts decline in these cognitive domains over time. Methods: Usual gait speed (m/s) over 6 m was measured at baseline in 2,776 Health, Aging and Body Composition Study participants (mean age ± SD 73.5 ± 2.8 years, 53% women, 37% blacks). The Digit Symbol Substitution Test (DSST) was administered at baseline and after 5 years to assess attention and psychomotor speed. We used multivariate logistic regression models to calculate the risk of DSST 5-year decline [>1 SD from mean change (9 points)] across quartiles of gait speed, adjusting for demographics, weight, physical activity, comorbidities, depression and Modified Mini-Mental State Examination. Results: After 5 years, 389 (17.1%) participants declined in DSST. Compared to those in the highest quartile of gait speed (>1.35 m/s), participants in the lowest quartile (<1.05 m/s) were more likely to decline in DSST independently of the considered covariates (OR 1.74, 95% CI 1.21–2.51, adjusted p for trend across quartiles = 0.006). Conclusions: In this cohort of older community dwellers, gait speed independently predicted a decline in DSST after 5 years.

Objective: To estimate prevalence and progression to dementia of cognitive impairment, no dementia (CIND), mild cognitive impairment (MCI), and relative subtypes, evaluating the relationships with daily functioning, cardiovascular diseases and vascular risk factors. Methods: We evaluated CIND and MCI in the Italian Longitudinal Study on Aging. The neuropsychological battery assessed global cognitive function, memory and attention. Two thousand eight hundred thirty participants were examined at baseline and after a mean follow-up of 3.9 ± 0.7 years. Results: The prevalence was 9.5% for CIND and 16.1% for MCI. Prevalence rates for CIND subtypes were 1.8% for amnestic, 2.3% for single nonmemory, 1.5% for multidomain, and 3.9% for CIND defined only on global cognitive function. The prevalence was 7.0% for amnestic, 7.8% for single nonmemory, and 1.3% for multidomain MCI. Incidence of dementia (per 1,000 person-years) was 7.63 in the total sample, 21.37 in CIND, and 13.59 in MCI. In MCI, rates ranged from 8.74 in amnestic to 40.60 in multidomain subtype. The highest incidence of 56.02 per 1,000 person-years was found in multidomain CIND. Both CIND and MCI increased by almost three times the risk of dementia at follow-up. Among baseline variables, only previous stroke and impairment in instrumental activities of daily living significantly increased the risk of dementia at follow-up. Conclusions: Both cognitive impairment, no dementia and mild cognitive impairment are frequent in the Italian elderly (2,955,000 prevalent cases expected) and significantly predict progression to dementia. Individuation of subgroups with different risk factors and transition rates to dementia is required to plan early and cost-effective interventions.