Like overactive bladder (OAB), the prevalence of frailty increases in association with increasing age, as does the proportion of adults living with multiple chronic conditions. Population forecasts predict a worldwide increase in the proportion of people aged over 65 years, and, as such the healthcare burden associated with common late life conditions such as OAB, multimorbidity and frailty will also increase. 

Frailty, but not age, has been associated with OAB [1].  Likewise, older adults with OAB have more comorbid conditions than those without OAB and are more likely to be impaired in activities of daily living [2]. Frailty is a clinical condition characterized by excessive vulnerability to endogenous and exogenous stressors. Frail older adults exhibit simultaneous deterioration in mobility, balance, muscle strength, endurance, nutrition, motor processing, cognition, and physical activity. As such, frailty is a multidimensional construct.  The aim of this study was to examine the relationship between frailty, OAB and comorbidity using a multidimensional assessment of frailty and to reaffirm the association of OAB with impairment utilising the Timed Up and Go test.

Older adult patients (65+) of both sexes were recruited from a secondary care continence clinic between January 2021 – January 2022.  OAB was diagnosed by experienced clinicians according to the ICS definition. Patients were divided into OAB and non OAB groups for the purpose of this analysis. Patients attending the clinic underwent a Timed Up & Go Test, (TUG) a short assessment of the time taken to rise from a standard armchair, walk 3m away and back to sit down again, and is conventionally used to assess fall risk, where conventionally a completion time ³12s indicates an increased risk for falls. Other researchers have used more conservative cut offs (14 & 20 seconds) and so these were also assessed for the relationship of these TUG values with OAB [3]. 
Comorbidity was assessed using the validated Charleson Comorbidity Index (CCI). This score consists of a weighted numerical value depending on the associated comorbidity, assesses the degree of severity and number of coexisting comorbidities. A higher score (increased comorbidity) is associated with a higher ten-year mortality risk. CCI was divided into four categories, “none” (CCI=0), “mild” (CCI= 1,2), “moderate” (CCI = 3,4), and “severe” (CCI ≥ 5).The Edmonton Frail Scale (EFS) is an 11 item multidimensional assessment of frailty encompassing mood, functional independence, medication usage, social support, nutrition, health attitudes, continence, burden of medical illness and quality of life.  Frailty is defined as a score of ≥6 increasing in severity with the numerical value until a maximum of 17.  Descriptive statistics were used to describe the population demographics and, according to the distribution of the data, parametric (mean, standard deviation, independent t tests) and non-parametric ( Wilcoxon, Mann-Whitney U) tests were used for comparisons between groups.  Differences in proportions were analysed using Chi-squared testing

This study included 303 patients (92 (30.4%) in the non-OAB group and 211 (69.6%) in the OAB group). Among all patients, 232 (76.6%) were female and 71 (23.4%) were male. The mean (SD) values for age (years), CCI, and TUG (seconds) were 79.24 (7.77), 1.89 (1.86), and 16.08 (7.90) respectively.
The distribution of EFS Frail in the OAB group is different from its distribution in the non-OAB group (59.7% v 34.8%, p-value<0.001). In OAB group 59.7% have EFS Frail while in non-OAB group 34.8% have the EFS Frail. TUG values in the OAB group (16.9) were statistically significantly different from those in the non-OAB group (14.1), p=0.002.  This relationship persists using cut points of 14s (OAB: 58.5 v non-OAB:39.1%) and 20s, (OAB: 30.3% v non-OAB: 16.3%) both have statistically significantly different distributions in the OAB and non-OAB groups (p=0.002, p =0.011).

This study found a statistically significant relationship between frailty and an OAB diagnosis in older adults when assessed using a multidimensional frailty scale. Similar to previous work, impairment in the TUG test was also associated with frailty.
There was no association with either age, like previous work, or CCI in this cohort. The lack of any relationship with CCI suggests that this index may be either insufficiently sensitive to identify the previously reported association of OAB with a statistically significantly greater number of comorbid conditions than in age matched older adults without OAB, or that this previously reported finding is not generalizable to other populations of older adults. 
Some caution needs to be exercised in drawing conclusions here, these data come from a secondary care cohort, and although the majority were community dwelling older adults, they may not fully represent a primary care population. Likewise, only approximately a quarter of the older adults in this cohort were male; whether this relationship is consistent for males needs further investigation.
The association between frailty and OAB, independent of comorbidity, suggests further in-depth investigation of urinary urgency as a facet of frailty and impaired health outcomes.

Older adults with OAB are more likely to be living with frailty.  This association exists using either a single (TUG) or multidimensional measure of frailty.  This association is independent of age and, in this cohort, co-existing comorbidity

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Continence 7S1 (2023) 100989
DOI: 10.1016/j.cont.2023.100989