**3. Frail patient with AF**

#### **3.1 Epidemiology**

 The collection of information and quantification on fragility syndrome leads to analyzing a wide range of data dispersion, from different ethnic groups, various forms of measurements, in addition to the disparate life expectancy in different countries.

 Fragility in the US has a higher incidence in white ethnicity [ 24 ], in Latin America and the Caribbean, there is data of great percentage disintegration, from 7.7 to 42%, with an average of 19.6% (data surpassed in North America, Europe, and Oceania) [ 25 ].

 Atrial fibrillation (AF) is the unprevalent supraventricular arrhythmia in the young population, 2–3 cases per 1000 inhabitants, but the number of cases grows *Use of Non-Vitamin K-Dependent Oral Anticoagulants in Elderly and Fragile Patients… DOI: http://dx.doi.org/10.5772/intechopen.103033*

considerably to 50–90 per 1000 people ranging from 62 to 92 years [26, 27], and its number will multiply by 2.5 times by 2050 [9, 28], the product of its greater emphasis on the detection of arrhythmia.

The finding can range from the simple taking of the pulse looking for its classic irregularity to the need to search for information through the use of implanted devices (pacemaker, cardio-defibrillators, loop recorder) or diagnostic methods, such as 24-hour Holter, smartwatches, pulse meters.

In fragile patients, AF is more frequent, although the data can widely vary from 4.4–75% by different measurement modalities [29].

In a systematic review that included 21 studies, from 1998 to 2010 on four continents, with a total of 61,500 participants over 65 years of age, a variable range of data ranging from 4.0% to 59.1% was found with a fragility prevalence of 10.7% (95% CI = 10.5–10.9). As is already known, this percentage increases with age and female sex with significant statistical data of p < 0.001; and when talking about pre-fragility, the percentage found is close to 42% [30].

The Framingham Heart Study shows us that age as a solitary variable is sufficient predictive value in elderly people aged 80–90 years to increase the probability of suffering a stroke or transient ischemic attack (stroke/TIA) by 23.5%. In this population follow-up, one in three people of European descent will suffer from AF throughout their lives [31, 32].

In the totality of patients over 85 years of age, between a quarter and half of the patients are fragile, so it could be considered, who expect that two-thirds of the long-lived population could be prevented or detected to avoid disabilities.

#### **3.2 Definition**

Fragility as a syndrome is more frequent in patients in the last decades of their lives. It is characterized by a state of greater vulnerability, where different stressors contribute to the loss of physiological reserves, with the subsequent rupture of the homeostatic balance.

The most frequent stressors that trigger this physiological harmony can be of different characteristics; from chronic conditions, such as diabetes mellitus, chronic obstructive disease, skin infections, such as erysipelas, respiratory sequelae left by COVID-19, heart failure, atrial fibrillation, hip fracture, and long periods of bed rest, stroke, loss of loved ones, widowhood, loneliness, and low economic level.

Fried et al. in 2004 [33] establishes a clinical syndrome, describing the presence of three or more criteria that are summarized in **Figure 4**.

When the loss of physiological reserves is affected by two noxas, it is called pre-fragility, which when new noxas are added to them, becomes fragility syndrome. Subsequently, if more decompensating factors are added, a dreaded disability could arise (**Figure 5**) [34].

#### **3.3 Fragile patient assessment tools**

To recognize fragility early, a comprehensive assessment is needed, using clinical, functional, behavioral and biological markers [35, 36] that can help measure or quantify through the weighting Activity of Daily Living (ADLs), using the Katz index (eating, clothing, personal hygiene, bathroom use, continence management, and mobility). At earlier stages, you can use the assessment of the Instrumental Activity


#### **Figure 4.**

*Clinical characteristics of fragility.*

#### **Figure 5.**

*Progressive deteriorate of independent patient.*

of Daily Living (IADLs), measured by the LOWTON index (use of the phone, shopping, preparing meals, take care of your home, laundry, use of transport, the correct taking of your own medication, the management of the home economy) [37] and the Charlson comorbidity index [38, 39].

If the evolution of the clinical phenotype of fragility is followed at 3 years, F patients with lower economic resources suffer greater comorbidities, such as frequent falls, stroke, thus worsening mobility and ADLs [40].
