Nutrition, frailty, and Alzheimer's disease.

Francesco Panza,Davide Seripa,Giancarlo Logroscino,Alberto Pilotto,Michele Giannini,Vincenzo Solfrizzi

doi:10.3389/fnagi.2014.00221

Abstract

Currently, available drugs for the treatment of Alzheimer's disease (AD) have only symptomatic effects, and there is an unmet need of preventing AD onset and delaying or slowing disease progression in absence of disease-modifying therapies. Substantial epidemiological evidence suggested the hypothesis that modifiable metabolic, vascular, and lifestyle-related factors may be linked to the development of late-life cognitive disorders (Solfrizzi et al., 2011). Among these proposed factors, one appealing link is the association between dietary habits and the occurrence of AD (Tangney, 2014). Among age-related conditions closely associated to dementia and cognitive disorders in late life, frailty is a multidimensional geriatric condition that reflects a multisystem physiological change and a nonspecific state of vulnerability (Fried et al., 2001), with an increased risk for different adverse health outcomes in older age, including disability, falls, hospitalizations, and all-cause mortality (Fried et al., 2001). Although the operational definition of frailty is still controversial, in general, two approaches predominate. The “phenotypic” or physical definition of frailty or the “biological syndrome model” proposed five components: exhaustion, unintentional weight loss, weakness, slow walking speed, and low levels of physical activity. The frail state is defined by the presence of three or more of these components, the pre-frail state is defined by only one or two of these characteristics, while older individuals are “robust” when they have none of these frailty components (Fried et al., 2001). Other definitions, criticizing this concept, promote a multidimensional approach with a definition of frailty based on a cumulative model, employing frailty indexes for the evaluation of this condition, calculated by considering the accumulation of potential deficits, i.e., the presence of diseases, abnormal laboratory values, symptoms, signs, or disabilities (Rockwood et al., 2004). For all frailty models, cognitive and affective disorders, physical activity, and nutritional status have been suggested as markers of frailty (Kelaiditi et al., 2014). In particular, cognition has been considered a major component of frailty, also associated with adverse health outcomes (Rockwood et al., 2004). Therefore, possible preventive interventions on cognitive-related outcomes of frailty, including AD and dementia, may be operated though the prevention of this geriatric syndrome and its associated components (Panza et al., 2011; Robertson et al., 2013). Of note, in frailty prevention, the impaired nutrition, and weight loss of frail older subjects may be addressed by focused nutritional interventions.

Highlights

Reviewed by: Albert Gjedde, University of Copenhagen, Denmark Estefania Toledo, University of Navarra, Spain †These authors have contributed to this work
PROPOSED DEFINITION OF COGNITIVE FRAILTY AS A NEW CLINICAL ENTITY IN OLDER AGE Epidemiological evidence strongly suggested that physical frailty may be linked to cognitive impairment (Solfrizzi et al, 2012) and decline in late life (SamperTernent et al, 2008), incident Alzheimer’s disease (AD) (Buchman et al, 2007), mild cognitive impairment (MCI) (Boyle et al, 2010), vascular dementia (VaD) (AvilaFunes et al, 2012; Solfrizzi et al, 2013), non-AD dementias (Gray et al, 2013), and AD pathology in older subjects with and without a diagnosis of dementia (Buchman et al, 2008) (Table 1)
A healthy diet may have a profound impact on many possible risk factors for AD and cognitive decline, so influencing the onset and progression of these disorders

Summary

Introduction

Reviewed by: Albert Gjedde, University of Copenhagen, Denmark Estefania Toledo, University of Navarra, Spain †These authors have contributed to this work. In an 11-years follow-up, higher adherence to both the DASH diet and a Mediterraneanstyle dietary pattern in older age was associated with a significant reduction in rates of global cognitive decline in the same population-based setting (Wengreen et al, 2013).

Results

Conclusion