Health-related quality of life and economic impact of urinary incontinence due to detrusor overactivity associated with a neurologic condition: a systematic review

Four studies provided information on the impact of UI in individuals with MS [16‐19]. Two of these studies [16, 17] assessed general health status as measured by the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) [20], a subjective measure of health status across eight domains with scores ranging from 0 (worse HRQoL) to 100 for each scale. The conclusions of the two studies differed, with the first study concluding that UI was not associated with SF-36 scores (independent of the impact of MS itself) [16] while the second study found that for the physical functioning and role-emotional domains, those with UI had lower SF-36 scores compared to those without UI (physical functioning: 42.67 vs. 62.42; role-emotional: 27.13 vs. 42.39, respectively; p < 0.05) [17].

The third study assessed the impact of bladder problems on HRQoL in individuals with MS using disease-specific measures, including the Incontinence Impact Questionnaire (IIQ-7), Urogenital Distress Inventory (UDI-6), and American Urological Association (AUA) Symptom Index. [18] Approximately 96% of individuals reported having bladder problems, with 41% reporting they were “moderately” or “greatly” bothered by frequent urination, 39% by UI associated with urgency, and 26% by activity. Furthermore, a substantial number of patients reported “somewhat” or “a great deal of” interference caused by bladder problems, and urinaryu problems impacted emotional health (31%), ability to perform household chores (22%), and physical recreation (28%). In addition, almost half of the patients reported that they would feel “mostly dissatisfied,” “unhappy,” or “terrible” if they had to spend the rest of their lives with their current urinary condition. These results indicate that UI is not only bothersome and troubling to people with MS but also results in substantial disability.

The fourth study compared HRQoL of OAB patients with MS (OAB+MS group) versus OAB patients without MS (OAB group) using select domain scores of the Kings Health Questionnaire (KHQ; another disease-specific HRQoL measure) and found that urinary symptoms had more impact on HRQoL in the OAB+MS group compared with the OAB group [19]. KHQ scores were significantly higher (indicating greater impairment) in the OAB+MS versus the OAB groups (respectively) in five domains: general health perception (56.3 vs. 33.3, p = 0.02), role limitations (50 vs. 36.1, p = 0.03), physical limitations (56.3 vs. 33.3, p = 0.02), social limitations (45.8 vs. 18.5, p = 0.002), and urinary symptoms (17 vs. 14, p = 0.05). Patients in the OAB+MS group, however, felt that their bladder symptoms had a lesser impact on their lives than those in the OAB group and perceived their incontinence symptoms to be less severe compared with the OAB group. Urinary symptoms in both groups were also shown to adversely affect including physical activities, sleep/energy, emotions, and relationships; however, this impairment was generally greater in patients with MS.

Four studies were identified assessing the impact of UI among patients with SCI [21‐24]. The first study compared SF-36 scores of 132 incontinent SCI patients using clean, intermittent catheterization (CIC) with those of the general population [22]. Incontinent SCI patients had significantly lower SF-36 scores across all domains (except for the energy and vitality scores in female cases) when compared with the general population (p < 0.05). The greatest detriments in incontinent SCI patients were in the physical functioning domain for both male and female patients (male patients vs. controls, 18.4 ± 3.2 vs. 85.3 ± 1.7, respectively, p < 0.001 and female patients vs. controls, 28.3 ± 4.4 vs. 72.0 ± 2.3, respectively, p < 0001). Scores for all other domains were also lower among SCI patients compared with the general population (detriments ranged from 7.7 to 55.6 points).

Similar results were reported in a separate cross-sectional study in 142 SCI patients in the UK [21]. SF-36 scores and KHQ scores of SCI patients with normal voiding function were compared with scores of incontinent SCI patients who were using various methods of bladder management. Incontinent SCI patients scored significantly lower than continent patients on the physical functioning and mental health domains of the SF-36, as well as on the physical component summary (PCS) and mental component summary (MCS) scores (p < 0.05). Moreover, incontinent SCI patients who were using CIC by an attendant, indwelling transurethral catheterization, or indwelling suprapubic catheterization had the lowest mental health domain and MCS scores compared with SCI patients who were continent or SCI patients using other forms of bladder management, such as self-CIC, reflex trigger, or bladder expression. KHQ scores corroborated these findings. SCI patients without UI had higher KHQ scores compared with incontinent patients requiring bladder management, with significant differences observed in the physical limitations, social limitations, personal relationships, and emotions domains (p < 0.05). The frequency of UI also had a substantial impact on HRQoL. Worse HRQoL scores were associated with increased frequency of incontinence, and SCI patients who experienced daily UI episodes had the worst SF-36 and KHQ scores. Mental health domain and MCS scores significantly decreased as the frequency of UI episodes increased (mental health: 77.4, no incontinence vs. 60.7, daily incontinence; p = 0.01; MCS: 42.2, no incontinence vs. 27.7, daily incontinence; p = 0.01). Significantly worse KHQ scores were also observed in the incontinence impact, social limitations, emotions, and severity measures domains as the frequency of UI increased (p < 0.05).

Baseline data from a recent interventional, randomized controlled trial in SCI patients with incontinence due to NDO further suggest that the HRQoL of these patients is greatly impaired [23]. HRQoL was assessed with the Incontinence Quality of Life (I-QOL) questionnaire and SF-36 before treatment with botulinum toxin A. I-QOL is a 22-item disease-specific HRQoL questionnaire with possible scores ranging from 0 (worse HRQoL) to 100 (higher HRQoL). At study baseline, the mean I-QOL score was 44 (range 9–82), with the greatest decrement noted on the social embarrassment domain (mean score = 33), and SF-36 scores ranged from 51 to 65, except for physical functioning, the average of which was 32. TheT authors noted that the physical functioning score might be more reflective of the physical impact of the neurologic condition rather than that of incontinence. However, significant improvements in the role-physical and role-emotional domains of the SF-36 were observed following botulinum toxin A treatment, implying that some degree of their general HRQoL impairment could be attributed to incontinence.

In addition to physical, mental, and psychological impairments, the final study in SCI patients suggests that UI also negatively affects sexual life [24]. Study participants with traumatic SCI reported via questionnaire that UI caused inconvenience with regards to sexual life. Those reporting that UI was more of an inconvenience in their lives were also more dissatisfied with their sexual life compared with those reporting that UI was less of an inconvenience. This correlation was significant for men but not for women (Spearman’s rho = 0.29, p = 0.021 vs. –0.18, p = 0.236, men vs. women, respectively).

Two relevant studies that assessed the impact of UI in people with Parkinson’s disease were identified. One study in Italy used the symptom bother component of the OAB questionnaire Short Form (OAB-Q SF) to assess the frequency and bother of frequency, urgency, nocturia, and incontinence symptoms in patients with Parkinson’s disease compared with healthy controls [25]. Scores ranged from 8 to 48, with higher scores indicating greater symptom bother. The study found that patients with Parkinson’s disease and urinary symptoms were significantly more bothered compared with healthy controls without Parkinson’s disease or urinary symptoms (18.71 vs. 12.37, respectively; p = 0.0001).

A study in Canada compared HRQoL of patients with Parkinson’s disease and UI versus Parkinson’s patients without UI [26]. The study utilized data from the Canadian Community Health Survey in which health status was assessed using the Health Utilities Index Mark 3 (HUI3), a 31-item questionnaire that assesses usual health status with the following eight attributes: vision, hearing, speech, ambulation, dexterity, emotion, cognition and pain, and discomfort. HUI3 scores range from −0.36 (worst possible health) to 1.0 (1.0 = perfect health). Overall utility scores were significantly lower in persons afflicted with both Parkinson’s disease and UI compared with those with Parkinson’s disease who did not have UI (0.39 vs 0.61, respectively, p < 0.05) or the general population (0.39 vs 0.83, respectively, p < 0.05). Furthermore, clinically important and statistically significantly lower scores were reported for the ambulation (−0.22 [CI −0.42 to −0.02, p < 0.05]), and emotion (−0.28 [CI −0.43 to −0.12, p < 0.05]) attributes by respondents with Parkinson’s disease and UI compared with those who were continent. The study thus suggests that UI has detrimental effects on both the physical and mental health of patients with Parkinson’s disease.

Five studies in stroke patients with UI were identified, which suggest that incontinent stroke patients have impaired functioning, lower life satisfaction, and higher rate of institutionalization compared with stroke patients who are continent.

Edwards et al. [27] interviewed 361 individuals 6 months post stroke and evaluated the impact of UI on functioning,life satisfaction, and social participation. In all, 16% of individuals were incontinent at 6 months, and these individuals were more impaired with respect to basic and instrumental Activities of Daily Living (ADL) scales. Incontinent stroke survivors were significantly less independent with respect to basic self-care, functional communication, and cognition compared with continent survivors (p < 0.0001), as measured by the Functional Independent Measure (FIM). Incontinent individuals also experienced significantly lower HRQoL and well being than continent individuals, as assessed by all other measures, and survivors had significantly lower emotional well-being (SF-12 MCS score) and significantly lower levels of life satisfaction (as measured by the Reintegration to Normal Living Index, RNL) compared with continent individuals (p < 0.0001). On average, incontinent individuals retained only 40% of their pre-stroke activities, whereas continent individuals retained 70%. UI in stroke patients was thus associated with greater dependence in basic and instrumental ADL, decreased participation in normal living, and lower life satisfaction. In a cross-sectional, clinical survey conducted in patients at least 1 month after their incident stroke (n = 407) at an acute stroke and neurological unit in Denmark [28], found that activity limitations were closely related to incontinence. Mobile velocity was significantly associated with severity of urinary symptoms (mean effect = 0.37, p = 0.01), and low Barthel Index (a measure of disability status) scores and reduced mobility velocity increased the risk of the prevalence (OR = 2.08, p = 0.03, and OR = 1.87, p = 0.05, respectively) and severity (mean effect = 0.21, p = 0.03 and mean effect = 0.22, p = 0.04, respectively) of incontinence symptoms.

The remaining three studies assessed the impact of UI on long-term outcomes in stroke patients, including disability, rate of institutionalization, and mortality [29‐31]. Kolominski-Rabas et al. [29] reported that, according to the Barthel Index, patients who were incontinent after a stroke were severely (39%) or moderately (18%) disabled at 2 years, whereas those who were continent after their strokes were only mildly disabled (26%) or independent (51%).

The rate of institutionalization among incontinent stroke patients ranged from 34% at 3 months post stroke [30] to 45% at 12 months post stroke [29], and was found to be significantly higher among incontinent stroke patients institutionalized at 1 year (45%) compared with those who were continent (5%; p = 0.001). [31] The risk of mortality at 2 years was also greater among stroke patients with UI compared with those without UI (odds ratio 4.43; 95% CI: 1.76 to 11.2; p = 0.002) [31].

The literature search identified two studies that assessed the impact of UI on HRQoL in people with spina bifida; however, neither study found a strong association between UI and HRQoL.The study by Valtonen et al. [24] (described above, which assessed sexual satisfaction and level of inconvenience due to UI among SCI patients) also assessed the impact of UI on the sexual life of individuals born with meningomyelocele and found that although UI caused some inconvenience, this inconvenience did not affect sexual satisfaction. The only other study that assessed the relationship between UI and HRQoL in spina bifida was a cross-sectional study in 460 patients at six centers in France using the SF-36 and VSP (Vecu et santé percu, a French generic HRQoL instrument) [32]. HRQoL scores in incontinent adults with spina bifida were not significantly different from those patients without UI, except for the bodily pain domain of the SF-36, in which the continent patient group had a higher score (p = 0.05). No significant differences were observed in the VSP scores among adolescent patients with UI compared with those without UI [32].