**2. Frailty: Current definition and main characteristics of the frail elderly**

The concept of frailty as a specific syndrome has based on the clinical experience of geriatricians and usually is clinically well recognizable. Usually it is characterized by weakness, weight loss, and low activity and is associated with adverse health outcomes (including falls, incident disability, hospitalization, and mortality) (Xue, 2011; Fedarco, 2011).

Geriatric Urinary Incontinence – Special Concerns on the Frail Elderly 115

alterations in urine storage and bladder emptying functions. These functions as well as urinary continence are maintained due to the integrity of the lower urinary tract, the nervous system, the visceral supporting mechanism (pelvic floor) and the urine production mechanism. There must also be adequate perception and interpretation of the urge to pass urine, as well as the physical capacity to go to the toilet and to perform the

The most relevant changes of lower urinary tract with aging are listed in Table 1.

**Bladder Morphologic changes:** 

 **trabeculation fibrosis** 

 **capacity** 

**Urethra** 

**= contractility** 

 **cellularity collagen deposit Functional changes: closure pressure outflow resistance** 

**Prostate Enlargement, hyperplasia** 

**Vagina cellularity** 

Table 1. Lower urinary tract: main physiological changes with aging

infections, urinary retention and outflow obstruction (Verdejo, 2000).

**Pelvic floor collagen deposit** 

 **autonomic nerves Diverticula's formation Functional changes:** 

 **ability to put off micturition** 

 **involuntary contractions post voiding residual volume** 

**Anatomical changes:** 

**epithelium atrophy** 

In general, it is accepted that detrusor muscle contractility, bladder capacity and ability to put off micturition decrease in both sexes with aging. In addition, the prevalence of bladder hyperactivity increases. In women the maximum pressure of urethral closure and length of the functional urethra decreases, and post-micturition bladder residual volume increases up to 50-100 ml. Physiologically, elderly people tend to excrete more urine at night, even when there are no exacerbating factors such as heart failure, venous insufficiency, renal disease or prostatism. In men the prostate increases in volume meanwhile hypoestrogenism in women affects both the genital apparatus and urinary tract. Thus, the healthy elderly individual is much more vulnerable to suffering urinary pathological processes such as incontinence,

 **connective tissue ratio Muscle weakness** 

activity.

Frailty is a non-specific state of vulnerability, which reflects multisystem physiological change. These changes do not always means a disease status, so some very elderly, are frail without a specific life threatening illness. Current thinking is that, not only the physical way contributes to this syndrome, because also psychological, cognitive, and social factors take a decisive role and need to be taken into account in its definition and treatment.

Together, these signs and symptoms seem to reflect a reduced functional reserve and consequent decrease in adaptation to different type of stressors, and perhaps even in the absence of extrinsic stressors. The overall consequence is that frail elderly are at higher risk for accelerated physical and cognitive decline, disability and death. All these frailty's characteristics can easily be applied to the definition and characterization of the aging process per se, and there is little consensus in the literature concerning the physiological/biological pathways associated with or determining frailty. It is probably true to say that a consensus view would implicate heightened chronic systemic inflammation as a major contributor to frailty (Fulop et al, 2011).

Many other authors have focused on the popular definition proposed and tested in the Cardiovascular Health Study in the United States and known as the phenotypic definition of frailty. That study defined frailty by the occurrence of at least 3 of the following 5 deficits in an individual: slow walking speed, impaired grip strength, a self-report of declining activity levels, unintended weight loss, or exhaustion. In addition to the phenotypic and other approaches, frailty is considered as a risk state caused by the age-associated accumulation of deficits (Rockwood & Mitnitski, 2011).

The frailty can be considered as a complex phenomenon, with multiple links and interactions between the clinical, functional, mental and social components. In this sense, the use of the Geriatric Comprehensive Assessment (GCA) could be very useful in the detection of the frail condition of an older people. Through assessment of general health (comorbidity), function, cognition, mood and motivation, the special senses, nutrition and medications, this tool facilitates identification of health issues and the appropriate intervention and follow-up for them. As part of a comprehensive management plan, CGA also supports continued independence and improved quality of life for an individual in association with reduced medical costs (Rockwood & Mitnitski, 2011; Rosen & Reuben, 2011).

Based on these concepts, a frail elderly would be a very old person (usually more than 80-85 years), with high comorbidity, functional handicaps, cognitive impairment and also limitations in the familiar and social areas. In this group of older persons, it is expected the highest known prevalence of UI of any group of age (around 50-70%).

In frail elderly, UI constitutes a syndromic model with multiple interacting risk factors, such as age-related physiologic changes, comorbidity, and common pathways between them, in which the accumulated effects of multiple impairments increase vulnerability to situational changes (Inouye et al, 2007).
