Frailty is a sate of vulnerability to insult, maybe in the form of a relatively minor stressor, from which the individual does not fully recover.  The prevalence of frailty increases with increasing age, from 6.5% in those aged 60–69 years to 65% in those aged 90 or over [1]. Frailty is more common in women than in men (16% versus 12%). In the United States, using the Fried model of frailty to persons aged 65 and older, 15% (95% CI: 14%, 16%) of the older non-nursing home population was frail, and 45% prefrail (95% CI: 44%, 47%) [2].  Chronic disease and disability prevalence increase steeply with frailty. Likewise, incident urinary incontinence (UI) in men and women over age 65 has been associated with a two-fold increased risk of impairment in activities of daily living (ADL), instrumental activities of daily living (iADL) and poor performance in measures of physical function, suggesting that incident UI may be an early marker of the onset of frailty.  In a similar fashion, older patients with overactive bladder (OAB) have been found to have significantly more comorbid conditions and a greater likelihood of having ADL impairments than those without OAB – a finding in both community dwelling and institutionalized older people.  OAB has been associated with an increased likelihood of impaired performance on the timed up and go test (TUGT), a single facet of frailty and has been found to be independent of age and comorbidity [3] .  This study examined the relationship between a multidimensional frailty scale, the Edmonton Frail Scale (EFS), the degree of comorbidity and the presence of OAB in older patients.

Consecutive male and female patients (>65y) attending a specialist continence clinic between June 1 2017 and June 1 2019 provided data for the EFS, TUGT, comorbid conditions and their demographics.  OAB was diagnosed according to the criteria of the International Continence Society. Data on comorbid conditions were used to calculate a Charlson Comorbidity Index (CCI) for each individual.  The EFS, a multidimensional score comprised of questions in 9 domains assesses general health, hospitalizations, number of medications, availability of help, medication omission, weight loss, mood, continence and a clock drawing test and timed up and go test is scored out of 17. Frailty was defined as EFS ≥6 (vulnerable).  The timed up and go test is an expression of the time in seconds it takes a subject to rise from a chair, walk 3 metres, return to the chair and sit.  An impaired TUGT (>10s) is an indicator of increased fall risk. The Charlson Comorbidity Index is a method of categorizing comorbidities of patients based on the International Classification of Diseases (ICD) diagnosis codes, routinely used in the clinic. Each comorbidity category has an associated weight (from 1 to 6), based on the adjusted risk of mortality or resource use, and the sum of all the weights results in a single comorbidity score. A score of zero indicates no comorbidities. Higher scores are associated with poor health outcomes or higher resource use. Scores in an OAB cohort were compared to a non-OAB cohort formed of patients >65 with incontinence due to other lower urinary tract symptoms or prolapse. Analyses comprised descriptive statistics and comparisons of proportions using the Chi squared test.

There were 149 OAB patients of mean (SD) age 80.1 (7.7) and 46 N-OAB patients of mean (SD) age 78.9 (7.4), p=NS. Patients were mostly female, OAB 113 (76.4%), N-OAB 35 (77.8%). The mean (SD) TUGT was higher in the OAB group, 16.9 (8.7)s than the N-OAB group, 13.6 (7.2)s, p=0.017. A greater proportion of the OAB group was classified as frail (58.3%) versus the N-OAB group (21.7%, p=0.007). There was no difference in the mean CCI score (1.6, (SD 1.6)) between groups (p=NS). Mean (SD) age (81.5 (7.9) versus 78.2 (7.2)years and mean CCI score, 2.0 (1.7), versus the non-frail, 1.2 (1.1), were statistically significantly higher in the frail, regardless of an OAB diagnosis, p=0.003 and p<0.0003, respectively.

OAB and urgency incontinence is significantly associated with frailty in older people when assessed by the Edmonton Frail Scale, an easy to administer scale which needs no formal training.  In this cohort, unlike in previous studies, OAB was not associated with any difference in Charlson Comorbidity Index.  This may have been an effect of the relatively small sample size. We did not assess the absolute number of comorbid conditions, as in previous studies.  Frail patients were more likely to have a higher CCI and to be older than non frail patients, regardless of OAB diagnosis. To what extent successful treatment of OAB may affect frailty status, if at all, remains to be seen.

In older people, OAB and urgency incontinence is yet another facet of the frailty syndrome.

Age Ageing, 2015. 44(1): p. 162-5.
J Gerontol A Biol Sci Med Sci, 2015. 70(11): p. 1427-34
Urology. 2017 Aug;106:26-31