Introduction
Parkinson’s disease (PD) is a progressive neurodegenerative disorder that affects multiple systems, manifesting with motor and non-motor symptoms. PD is characterized by the loss of dopaminergic cells1,2.
In most cases, the etiology of PD is idiopathic (85-90%), while in the remaining cases, PD has a genetic cause3,4. Age is the most important risk factor: it begins between 60 and 70 years of age. It is more common in men versus women, with a ratio of 1.4:15.
The clinical signs can be divided into motor and non-motor symptoms. The former includes tremor, postural instability, rigidity, and bradykinesia, while the latter includes GI, genitourinary, and cognitive symptoms, among others, which all have a negative impact on the patients’ the quality of life (QoL)6,7.
Urinary symptoms are the most prevalent non-motor manifestations of PD. They affect QoL by interfering with daily activities and health status, causing concern and discomfort. The most frequently observed symptoms are urinary urgency and frequency.
Urinary symptoms are the most prevalent non-motor manifestations of PD. They affect QoL by interfering with daily activities and health status, causing concern and discomfort. Their frequency ranges from 17% up to 27% for voiding symptoms and from 57% up to 83% for storage symptoms. The most frequently observed symptoms are urinary urgency (33% up to 54%) and urinary frequency (16% up to 36%)8,9.
The World Health Organization defines QoL as “an individual’s perception of their position in life in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards, and concerns”8,10.
The objective of this study is to compare the QoL of PD patients based on their urinary symptomatology in a tertiary referral hospital.
Materials and methods
This was a comparative, observational, cross-sectional, and prospective study conducted on patients treated from a tertiary referral hospital during 2023. Patients clinically diagnosed with PD, > 30 years, of both sexes, were included. No patient was excluded or removed from the study.
The diagnosis of PD was considered in patients with at least three of the following signs: bradykinesia, resting tremor, rigidity, or postural instability, with response to dopaminergic drug11.
Patients were interviewed in outpatient consultation. Age, sex, marital status, occupation, academic degree, and comorbidities were collected. The following instruments were applied:
- Hoehn and Yahr scale, to identify the severity of the disease in terms of mobility impairment, postural reflexes, laterality, and disability. The scoring ranges from 0 to 5, with 0 being asymptomatic, 1 indicating unilateral motor involvement, 2 indicating bilateral involvement without balance impairment, 3 indicating bilateral involvement with altered postural reflexes, 4 indicating severe disability with the ability to walk or stand unassisted, and 5 indicating confinement to bed or wheelchair11.
- International prostate symptoms score (IPSS), to evaluate urinary symptoms caused by the prostate. It consists of seven questions that assess urgency, straining, hesitancy, nocturia, urinary frequency, decreased urine stream, and intermittency of urine flow. Each question is scored from 0 up to 5 points, with a total score ranging from 0 up to 35 points. The options for scoring are never, < 1 in 5 times, less than half of the time, about half of the time, more than half of the time, and almost always. Questions 1, 3, 5, and 6 evaluate obstructive symptoms, while questions 2, 4, and 7 assess storage symptoms. Based on the result, symptoms are categorized as mild (0 to 7 points), moderate (8 to 19 points), or severe (20 to 35 points). A lower score indicates lower symptomatology, and vice versa. An eighth question assesses the impact on QoL and is scored from 0 up to 6; this is analyzed separately. Although its primary use is in men, it is also useful for evaluating the severity of lower urinary tract symptoms in women12,13.
- SF-36 Health Survey (SF-36), to evaluate QoL. It consists of 36 questions that assess a total of 8 domains: physical functioning, physical role, bodily pain, general health perceptions, vitality, social functioning, role limitations, and mental health. Each domain is scored from 0 up to 100, with a higher score indicating better QoL14,15.
Based on the results of the ISPSS, patients were categorized into 3 groups: with mild, moderate, and severe urinary symptomatology. The groups were compared in terms of the domains of the SF-36 scale for QoL.
Descriptive statistics was used for data analysis. To compare QoL among the groups with different urinary symptomatology, the Kruskal–Wallis test was used. Spearman’s rho coefficient was used for correlation analysis. Data were processed using the statistical software SPSS v. 25 for Windows. p ≤ 0.05 was considered statistically significant.
Patients signed an informed consent form. The data obtained were used solely for scientific purposes, and participants’ anonymity was preserved at all times. The protocol was approved by the Local Health Research Committee No. 2101 of the Instituto Mexicano del Seguro Social.
Results
A total of 37 PD patients were evaluated, including 22 (59.5%) men and 15 (40.5%) women. The mean age was 62.3 years (range, 43-84; standard deviation, 10.79). A total of 75.7% of the patients were married, 29.7% had completed primary education, 31.6% were engaged in household work, and 67.6% did not exhibit any comorbidities during the study. The details of the clinical and sociodemographic characteristics of the patients are shown in Table 1.
Table 1. Clinical and sociodemographic characteristics of the patients (n = 37)
| Sex | |||||
|---|---|---|---|---|---|
| Female | Male | ||||
| 40.5% | 59.5% | ||||
| Age (years) | |||||
| 40-49 | 50-59 | 60-69 | 70-79 | 80-89 | |
| 16.2% | 21.6% | 37.8% | 18.9% | 5.4% | |
| Civil status | |||||
| Single | Married | Widow | Coupled | ||
| 5.4% | 75.7% | 8.1% | 10.8% | ||
| Education | |||||
| Primary or lower | Secondary or higher | ||||
| 45.94% | 54.05% | ||||
| Occupation | |||||
| Housewife | Retiree | Other | |||
| 31.6% | 26.3% | 40.54% | |||
| Comorbidities | |||||
| Diabetes | Hypertension | Both | None | ||
| 2.6% | 13.2% | 15.8% | 65.8% | ||
| Hoehn Yahr Scale | |||||
| 0 | 1 | 2 | 3 | 4 | 5 |
| 5.3% | 5.3% | 21.1% | 50% | 10.5% | 5.3% |
Regarding clinical stage, 50% (19 patients) were in stage 3, 21.1% (8 patients) in stage 2, and 10.5% (4 patients) in stage 4 of the Hoehn and Yahr scale.
Patients were on dopaminergic therapy as follows: 21 (56.75%) on levodopa-carbidopa and pramipexole, 10 (27%) on levodopa-carbidopa and biperiden, 3 (8.1%) on levodopa-carbidopa only, 2 (5.4%) on pramipexole and biperiden, and 1 (2.7%) on levodopa-carbidopa, pramipexole, and rasagiline.
Reported side effects included dyskinesias in 18 (48.64%) patients and behavioral changes in 2 (5.4%) (one aggression and inappropriate behaviors, and 1 emotional lability).
Regarding obstructive urinary symptoms, between 13.2% and 34.2% of patients reported discomfort approximately half the time to almost always. The most frequent urinary sign was decreased caliber of the urinary stream (34.2%). As for storage symptoms, between 23.7% and 28.9% reported impairment approximately half the time and almost always. The most common storage symptom was urinary frequency (28.9%). In question 8, 31.6% of patients reported feeling rather dissatisfied to very unhappy.
The comparison between groups with mild, moderate, and severe urinary symptomatology in the physical nature domains of the SF-36 scale is illustrated in Table 2. The comparison in mental nature domains is shown in Table 3. Significant differences were found only in the domains of pain and social function (p < 0.05). Only correlations between the physical role, pain, physical function, and vitality domains with urinary symptoms were significant (p ≤ 0.05), with rho ranging from 0.28 up to 0.4 (Tables 2 and 3).
Table 2. Quality of life and urinary symptom comparison. Physical Domains of SF-36
| Quality of life domains (SF-36) | Urinary symptoms (%) International prostate symptoms score | p Kruskal–Wallis test | Spearman Rho | ||
|---|---|---|---|---|---|
| Mild (n = 13) | Moderate (n = 17) | Severe (n = 7) | |||
| Physical Role | 0.116 | −0.283 (p = 0.0445) | |||
| No impairment | 30.76 | 0 | 14.28 | ||
| Mild | 15.38 | 29.41 | 0 | ||
| Very mild | 0 | 0 | 0 | ||
| Moderate | 0 | 0 | 0 | ||
| Severe | 7.69 | 17.64 | 0 | ||
| Very severe | 46.15 | 52.94 | 85.71 | ||
| Pain | 0.027 | −0.400 (p = 0.007) | |||
| No impairment | 30.76 | 11.76 | 14.28 | ||
| Mild | 23.07 | 23.52 | 0 | ||
| Very mild | 7.69 | 5.88 | 0 | ||
| Moderate | 15.38 | 11.76 | 0 | ||
| Severe | 7.69 | 11.76 | 14.28 | ||
| Very severe | 15.38 | 35.2 | 71.42 | ||
| General state of health | 0.176 | −0.151 (p = 0.187) | |||
| No impairment | 0 | 0 | 0 | ||
| Mild | 0 | 5.88 | 0 | ||
| Very mild | 7.69 | 0 | 0 | ||
| Moderate | 15.38 | 29.41 | 14.28 | ||
| Severe | 23.07 | 11.76 | 0 | ||
| Very severe | 53.84 | 52.94 | 85.57 | ||
| Physical function | 0.086 | −0.310 (p = 0.031) | |||
| No impairment | 7.69 | 5.88 | 14.28 | ||
| Mild | 15.38 | 11.76 | 0 | ||
| Very mild | 15.38 | 0 | 0 | ||
| Moderate | 0 | 23.52 | 0 | ||
| Severe | 30.76 | 5.88 | 0 | ||
| Very severe | 30.76 | 52.94 | 85.71 | ||
|
SF: Short form. |
|||||
Table 3. Quality of life and urinary symptom comparison. Mental Domains of SF-36
| Quality of life domains (SF-36) | Urinary symptoms (%) International prostate symptoms score | p Kruskal–Wallis test | Spearman Rho | ||
|---|---|---|---|---|---|
| Mild (n = 13) | Moderate (n = 17) | Severe (n = 7) | |||
| Vitality | 0.077 | −0.322 (p = 0.026) | |||
| No impairment | 0 | 0 | 14.28 | ||
| Mild | 23.07 | 11.76 | 0 | ||
| Very mild | 7.69 | 0 | 0 | ||
| Moderate | 7.69 | 17.64 | 0 | ||
| Severe | 30.76 | 17.64 | 0 | ||
| Very severe | 30.76 | 52.94 | 85.71 | ||
| Social function | 0.021 | −0.240 (p = 0.076) | |||
| No impairment | 0 | 0 | 0 | ||
| Mild | 7.69 | 11.76 | 0 | ||
| Very mild | 7.69 | 0 | 0 | ||
| Moderate | 7.69 | 23.52 | 0 | ||
| Severe | 38.46 | 35.29 | 14.28 | ||
| Very severe | 38.46 | 29.41 | 85.71 | ||
| Emotional role | 0.099 | −0.270 (p = 0.080) | |||
| No impairment | 15.38 | 17.64 | 0 | ||
| Mild | 0 | 0 | 0 | ||
| Very mild | 0 | 0 | 0 | ||
| Moderate | 46.15 | 41.17 | 14.28 | ||
| Severe | 0 | 0 | 0 | ||
| Very severe | 38.46 | 41.17 | 85.71 | ||
| Mental health | 0.1515 | −0.220 (p = 0.095) | |||
| No impairment | 0 | 0 | 0 | ||
| Mild | 15.38 | 11.76 | 0 | ||
| Very mild | 7.69 | 0 | 0 | ||
| Moderate | 15.38 | 17.64 | 0 | ||
| Severe | 15.38 | 23.52 | 28.57 | ||
| Very severe | 46.15 | 47.05 | 71.42 | ||
|
SF: Short form. |
|||||
The correlation between the impact on QoL (question 8 of the IPSS) and the SF-36 domains was not significant (p > 0.05), except for the emotional role domain (r = −0.404; p = 0.013).
Discussion
PD is a chronic and progressive disorder affecting multiple systems, being a heterogeneous disease1.
In this study, a predominance of males over females was observed at a ratio of 1.5:1, very similar to other reports16.
PD affects individuals > 60 years, with peaks around 85 years16,17. We should mention that in this population, 75% of patients were < 70 years, with a mean age of 62.3 years. Only 2 patients were reported > 80 years.
Up to about 46% of our patients reported primary level education or lower, which is similar to what former studies have reported in Latin America18.
We should mention that the diagnoses identified in this study were diabetes and arterial hypertension. Most did not report other diagnoses. Other reports identify sleep disturbances (81.3%) and depression (37.1%) as the most frequent comorbidities18,19. This is an area of opportunity to improve the study and management of these patients.
Most patients in this study are on levodopa along with a dopaminergic agonist, which is consistent with other reports from Mexico and Latin America20,21.
A total of 51% of patients manifest motor complications associated with levodopa22. The results presented today show a very similar percentage (52.6%).
Regarding the severity reported in this study according to the Hoehn-Yahr scale, 73% of patients were in stages 2 and 3. In other Mexican studies, similar severity has been reported in up to 93% of cases. There seems to be a greater impact on QoL within physical and mobility areas, but in the present study, the most affected domains are pain, social function, and emotional role22,23.
The most common urinary symptoms in this study were urinary frequency (storage) and decreased caliber of the urinary stream (obstructive), while other studies report nocturia in up to 60% and urinary urgency in 54% as the most frequent symptoms9,24.
The presence of urinary symptoms affects social relationships, intimacy, and participation in social activities, as it causes embarrassment, resulting in a negative impact on QoL25,26. The findings of the present study corroborate this, as the assessment of QoL in the IPSS corresponds to the rating of domains of the SF-36 instrument specific to that construct.
Storage symptoms have a greater impact on QoL particularly as PD progresses27,28. In this study, no differentiation was made by the intensity of obstructive or storage symptoms, yet significant impairment was found in five of the eight SF-36 domains.
QoL assessed by the SF-36 scale did not correlate significantly with question 8 of the IPSS, except for the emotional role domain, with moderately high figures (0.404). A construct as complex as QoL will hardly be properly evaluated with a single question. These results suggest that the emotional aspect has the greatest impact on QoL.
The findings may have been affected by the relatively small sample size. Studies with a larger sample will contribute to filling the existing gap in current reports on the topic.
Conclusions
The most frequent urinary symptoms were urinary frequency and decreased caliber of the urinary stream. The pain and social function domains of QoL showed a significant decrease according to urinary symptoms. Physical role, pain, social function, and vitality showed a significant correlation with urinary symptomatology.
Funding
The authors declare that they have not received funding.
Conflicts of interest
The authors declare no conflicts of interest.
Ethical disclosures
Protection of human and animal subjects. The authors declare that no experiments were performed on humans or animals for this study.
Confidentiality of data. The authors declare that they have followed the protocols of their work center on the publication of patient data.
Right to privacy and informed consent. The authors have obtained the written informed consent of the patients or subjects mentioned in the article. The corresponding author is in possession of this document.
Use of artificial intelligence for generating text. The authors declare that they have not used any type of generative artificial intelligence for the writing of this manuscript nor for the creation of images, graphics, tables, or their corresponding captions.
