Globally, malnutrition is a serious public health problem; it is a clinical disorder that encompasses a range of anthropometric deficiencies: from undernutrition (Protein-Energy Malnutrition, resulting from inadequate intake of energy and/or protein, or the inability to absorb energy and/or digest protein in adequate amounts) to other nutrition disorders including a high body mass index such as overweight and obesity. (1,2)

PEM (Protein Energy Malnutrition) is typically defined by the presence of both a low body mass index and low serum albumin levels. It is associated with a variety of metabolic abnormalities, including steatosis, increased lipolysis and fatty acid oxidation, decreased circulating amino acids, decreased peroxisome number and function, and impaired mitochondrial function.

Malnutrition can lead to immune dysfunction and increased mortality from infections.

The prevalence of caloric-protein malnutrition increases with age in both sexes and has a negative impact on health, cognitive, physical functioning, and quality of life, with poor disease outcomes and more frequent and longer hospital stays. (2,3,4)

The European Society for Clinical Nutrition and Metabolism recommends a two-step approach to the diagnosis of malnutrition; first, screening for the risk of malnutrition, and second, assessment for the diagnosis and classification of the severity of malnutrition.

There are five malnutrition criteria to be considered, classified as phenotypic criteria (involuntary weight loss, low body mass index, and reduced muscle mass) and etiologic criteria (reduced food intake or assimilation, and inflammation or disease burden). To diagnose malnutrition, at least one phenotypic criterion and one etiologic criterion should be present.

Phenotypic metrics are proposed to classify severity in stage 1 (moderate) and stage 2 (severe) malnutrition. (2,5)

Malnutrition is more prevalent in the elderly than in their younger counterparts. There are many social, environmental and health factors that may contribute to the development of malnutrition in this population group. (6,7)

The elderly are at risk of protein-energy malnutrition (PEM), resulting in altered body composition (decreased lean body mass) and body cell mass.

This category includes about 5 percent of community-dwelling elderly, 50 percent of those in rehabilitation, 10 percent in residential nursing homes, and 35 percent in hospitals.

There is strong evidence that early identification of malnutrition risk, followed by timely and appropriate intervention, is associated with better nutritional care and lower incidence of malnutrition.

Performing a nutritional status assessment enables identification of patients who are already malnourished or at risk of caloric-protein malnutrition or with specific nutrient depletion who require specific therapeutic intervention.

To monitor the adequacy of any nutritional support, it is important that screening be conducted regularly so that the danger of malnutrition can be identified early by correcting it with appropriate interventions. Attendance is individualized based on individual problems and the possible occurrence of new situations that may pose risks of malnutrition.

Per le persone anziane, la cadenza dello screening sulla malnutrizione dipende dal contesto in cui risiedono. In the hospital setting, it is recommended that it take place on a weekly basis. (2,5)

Acute or chronic diseases and the interference of their treatment could also lead to worsening malnutrition, mainly undernutrition, due to altered metabolism. Malnutrition (undernutrition), for example, in those with diabetes leads to reduced muscle function and wound healing, decreased bone mass, immune dysfunction, and general functional decline.

Malnutrition could alter pancreatic hormone, adipocytokine, and cytokine responses in individuals with type 2 diabetes and thus predispose these individuals to an increased risk of more severe forms of diabetes.

While obesity and overweight status are known risk factors for the development of type 2 diabetes, there is emerging evidence that type 2 diabetes also occurs in normal or underweight individuals, especially in individuals with Low Body Mass Index. (1)

It is believed that the etiology, pathophysiology, and metabolic control of diabetes, regardless of whether it is type 1 or type 2, share common traits with frailty and cognitive impairment.

Hyperglycemia, hypoglycemia, obesity, vascular factors, physical inactivity, and malnutrition are important risk factors for cognitive deterioration and frailty in the elderly with diabetes.

Diabetes mellitus is closely linked to cognitive decline and dementia. In a meta-analysis of 144 prospective studies, diabetes conferred an approximately 1.5-2.0-fold increased risk. This cognitive impairment in patients with diabetes mellitus tends to affect not only verbal and visual memory, but also attention, information processing capacity, and executive function. (8)

In addition, diabetes leads to an increased risk of disability of about 50-80%; this is due to the high glucose concentrations that can lead to chronic systemic inflammation, which is part of a multifactorial process, leading to rapid loss of strength and decreased quality of skeletal muscles. This situation can worsen with poor glycemic control. (9)