The prevalence of UI in the sample of older adults living in Alfenas, MG was 21%. Studies carried out in Brazil for both sexes showed a prevalence of 20.9–38.4%. There is important variability in the literature regarding available UI prevalence data. [7, 21, 22, 23] This can be justified due to the methodological differences adopted by previous studies, the choice of instrument used to identify UI and the sample choice in relation to sex and age group included in the study. The prevalence of UI for older adult females was 26.9% and 11.2% for males. Few studies in Brazil have investigated the prevalence of UI for both sexes. Previous national data demonstrated that the prevalence of UI ranged from 26.2–60% among older adult women and from 10.7–18.3% among older adult men living in communities. [7, 21, 22] UI was more prevalent in women in all studies, and this finding can be justified due to the differences between male and female urethral length, previous history of pregnancies and births, as well as hormonal changes related to the aging process.[24]
The most frequent type of UI among older adults according to the loss situations reported by ICIQ-SF was urgency, which corroborates the data presented by Abufaraj et al. (2021) [25]; this study identified that the prevalence of UUI increased significantly among women aged 60 or over (p = 0.002) with prevalence rates of 49.5% when compared to other types of UI for the same age group. The presence of UUI is also related to age in healthy older adults due to structural and functional changes in the bladder, prostate and nerve connections, in addition to musculoskeletal dysfunctions commonly reported by older adults, which can culminate in nerve compressions and influence the continence mechanism. [26]
When analyzed using the ICIQ-SF, our study showed that the majority of older adults reported that the loss occurred in small quantities. Urinary loss in the total sample had a low impact on daily activities. Few studies used the ICIQ-SF to identify urinary loss and when used, analysis by subitems was not performed. This analysis in our study allowed us to identify the most common type of UI in this population, in addition to understanding the impact of UI on the daily activities of these older adults. The average presented indicates a slight impact on daily activities. However, the low impact on activities may be related to the fact that the majority still loses a small amount, meaning that the loss does not yet represent a limiting factor for the activities of the older adults included in the sample. Furthermore, the ICIQ-SF contains only one question related to the impact on activities of daily living, and another functional assessment instrument with more domains related to activities could better track the functional impact of urinary loss to analyze this variable.
The loss situation most reported by women was UUI (20.8%), followed by SUI (19.8%). Some factors may justify the association between UUI and aging in women, including parity, delivery mode, higher body mass index, previous pelvic surgery and comorbidities such as diabetes mellitus and history of hypertension. [27] A study aimed to evaluate the prevalence and correlation of urinary incontinence and overactive bladder in women and identified that the occurrence of UUI increases with age, and the number of overactive bladder conditions increased significantly in older adult women over 65 years of age. [28]
When we analyzed data from the total sample, there was a high frequency of older adults with multimorbidity (84.3%). Furthermore, 98.1% of incontinent older adults had more than three health conditions. The presence of multimorbidity is related to a greater risk of death, functional decline, and reduced life expectancy for this population.[3] Furthermore, the presence of many morbidities can affect urinary control and the ability to go to the bathroom, and the impact can be even greater when these are associated. The analysis of urinary loss associated with the presence of multimorbidity is a differential of this study, since it is a great challenge for geriatrics and gerontology professionals to manage this condition in older adult patients at any level of healthcare.
Regarding incontinent older adults, 39% screened positive for depressive symptoms. UI and depressive symptoms are multifactorial and may share causal mechanisms, as both are linked to the serotonergic and noradrenergic systems. Furthermore, urinary incontinence can result in reduced self-esteem, restricted participation and social isolation, triggering or exacerbating depressive symptoms. On the other hand, depressive symptoms and the use of antidepressants may be associated with restricted social contacts, functionality and motivation, inducing hormonal and mobility deficits that may contribute to the presence of UI. [29, 30, 31]
Higher BMI in the regression model was associated with the presence of UI. Similar results were presented in a community sample in the city of São Paulo, with an association between BMI ≥ 25 and UI (OR 1.25, CI 1:04 − 1:49, p = 0.018).[32] The increase in body mass index may be related to increased intra-abdominal and intravesical pressures, followed by overload on the pelvic floor in the elderly [33] and decreased pressure transmission to the urethra. Systemic mechanisms in obese individuals such as oxidative stress and neurogenic effects may also be involved and cause vascular and neural damage, which results in urethral dysfunction and failures in nerve conduction for adequate contraction of the pelvic floor muscles. Furthermore, biomechanical compensations related to postural changes due to obesity influence the appropriate positioning of the pelvis and impact the muscle contraction mechanism. [34]
UI was associated with TUG (OR 1.056; p 0.031). These findings are in line with those found by Okumatsu et al. (2021). These authors found that better physical function in a sample of older adult Korean women assessed by the TUG was significantly associated with a lower risk of UI, particularly urgency and mixed, among older adult women. [35] The TUG is a test to assess mobility in the lower limbs. When we think about the task performed by the test (getting up from the chair, walking 3 and sitting down again) and identifying the time to perform this task, it can tell us a lot about urinary loss. A shorter time to perform the task, as well as postural changes to perform the test, reproduce an individual’s daily activity and these variables can influence the occurrence of UI. The loss may occur due to the fact that the older adult is unable to reach the bathroom due to the slowness of performing the task, or even due to the increased overload on the pelvic floor when performing the function of getting up and sitting in the chair. In our study, we focused on evaluating only in relation to the time to perform the task, as recommended in the test, indicating that the worse performance in the TUG, meaning the more time the individual spends to perform the task, the greater the chances of urinary loss occurrence.
UI was not related to gender, polypharmacy, frailty, physical activity, self-perceived health, Quick Screen score, handgrip strength, frailty, or the presence of pain in the logistic regression model. Previous studies point to data that contradict our findings. Batmani et al. (2019) carried out a meta-analysis to identify the factors associated with UI in older adult women and identified a significant association with smoking (p < 0.001), age (p < 0.001) and education (p < 0.001). [8] Negative self-perception of health and polypharmacy were also associated with the occurrence of urinary loss in older adults. [30] Regarding the presence of pain, Kim et al. (2015) [36] investigated 1,399 Japanese women living in the community aged between 75 and 84 years and identified that participants with UI were more likely to feel pain (76.0%) than those without UI (P < 0.001). We did not identify previous studies that investigated the risk of falls and UI using QuickScreen.
The controversial findings in the literature regarding prevalence data and associated factors in our study compared to previous ones can be justified by the great methodological variability for identifying UI, as well as the factors related to this condition. Furthermore, the heterogeneity in the sample choice in relation to sex, age, and geographic location also makes it difficult to compare previous results.
The present study has some limitations. The cross-sectional design does not allow establishing a temporal relationship between the variables. Although the MMSE was used to exclude older adults with cognitive impairment, a memory bias related to urinary loss reported by the ICIQ-SF could influence the results of this study. On the other hand, its strengths include a population-based sample with older adults of both sexes, which guarantees representativeness of the studied population. Furthermore, the instruments used in the study to identify the dependent variable (UI) are valid instruments and recommended by the ICS for identifying urinary loss. We should also highlight that the other instruments used to identify the clinical and functional variables studied, such as depressive symptoms, risk of falls, and frailty screening, are also validated instruments for the older adult population, providing a more robust and assertive analysis for screening and identifying these variables.