The global interest in the study of aging processes and age-related diseases is due to the rise in the elder’s proportion associated with an increased sanitary implication. Frailty constitutes a precise measurement of aging symptoms and it indicates a multidimensional syndrome of energy, physical ability, and cognition loss. The frailty has been considered as an avoidable syndrome and it was suggested that it could be reverted in its earlier stages. Thus, we conducted a cross-sectional study in Belgian elders (n = 124, aged 65 and over), classified according to their frailty status, in order to increase evidence related to frailty and to find parameters that could be used as early indicators.
The current study examined the relationship between frail status and cognitive function in Belgian elderly. We confirmed that physical frailty is correlated with a decline in cognitive functions, which support previous findings. Indeed, data from the Rush Memory and Aging study found that higher levels of frailty were associated with a faster rate of decline in all cognitive domains . Furthermore, the results of Wu et al. (2015) indicated that the appearance of memory impairment may indicate its association with higher frail status, suggesting that existing cognitive impairment is a risk factor for an additional frail decline . Also, it has been shown that cognitive function across all domains was significantly poorer in frail participants than non-frail. Poor cognition was also linked to weakness and walking speed . However, our findings contradict some studies suggesting the absence of an association between memory decline and frailty [7, 21, 22]. This discrepancy could be explained by the size or the homogeneity of the samples in these studies [7, 21; 22].
Biological and psychological factors, including neuropathology, cardiovascular disease, inflammation, hormonal changes, nutrition, social vulnerability and isolation have been suggested to explain the link between frailty and cognition . In the present study, we tried to find an explanation for this association. Thus, several biochemical measures, frail status assessments and neuropsychiatric assessment, including the Mini-Mental State Examination has been performed in a population of Belgian elderly patients.
Some biochemical measures were associated with frailty. In fact, frailty was associated with CRP and albumin levels. It is well known that serum albumin is the most abundant blood protein in serum and is used as a marker of nutritional status. Hypoalbuminemia can reflect complications in different systems in elderly subjects. Since frailty is related to dysfunction in several organs, that could explain the observed inverse association between albumin and frailty index in the study population. These data are in accordance with other studies demonstrating that low albumin concentrations were associated with higher frailty scores [24–26]. Recently, hypoalbuminemia was associated with chronic inflammation . Indeed, chronic low-grade inflammation has been found to be related to organ damage, muscle waste and chronic diseases, which are hallmarks of frailty . On the other hand, chronic inflammation appears as a consequence of chronic diseases such as Alzheimer dementia and atherosclerosis . This phenomenon has been linked to both cognitive function and frailty . Furthermore, several studies support the direct association between serum CRP levels and frailty in elders . In accordance, we found that elevated levels of CRP were associated with higher frailty scores in the study population.
Furthermore, malnutrition has also been associated with hypoalbuminemia . Hence, the observed correlation between frailty and albumin deficiency could reflect a poor nutritional status in the studied population, suggesting that malnutrition is associated with higher frailty.
Nutritional deficiencies could reflect insufficient micronutrient intake. Knowledge about the relationship between micronutrient status and frailty could promote interventions to correct micronutrient deficiencies and thus could ameliorate frail people status. In fact, insufficient serum 25-hydroxyvitamin (25(OH) D) concentrations were associated with frailty status and measures of physical performance . Contrary to the literature, we could not find an inverse correlation between Vitamin D and frailty score [5, 25, 31]. However, this is comparable to data of Schoufour et al. (2015) study, conducted on elderly people with intellectual disabilities . Furthermore, the Vitamin D levels were higher in frail and severely frail patients compared to non-frail. This could be explained by the supplementation since sufficient 25(OH) D was considered crucial for frailty prevention. Recently, it has been reported that among the hospitalized elders, deficiency of Vitamin D was prevalent suggesting a necessity to supplement this Vitamin in order to maintain the required levels .
In addition, our study confirms the existence of an association between the frequency of frailty and the number of drugs prescribed. Indeed, previous studies indicated that frail patients were likely to receive a more important number of drugs than non-frail ones [33, 34]. Also, it was reported that each additional drug was associated with frailty with an odds ratio > 1[33; 35–37]. The enhancement of the interactions and adverse reactions associated with each additional prescription could explain the effect of multiple drugs intake on frailty. Herr et al. (2015) suggested that polypharmacy may be utile to identify older patients, whose health is more susceptible to be deteriorated and then to carry out corrective actions with regard to physical activity, nutrition, and the control of chronic diseases .
The multivariable model using logistic regression identified dementia, polypharmacy ≥ 5, living in a nursing home, and decrease of ADL as significant (P < 0.05) predictors of frailty. Our findings are relevant to social and medical policy formulation. The knowledge of factors associated with frailty represents target conditions for programs and policies directed at reducing frailty in the elderly population.