Hypothesis / aims of study
In recent years, various opinions have been reported on prevention of urinary incontinence. Instructions for improving ADL are recommended aiming to reduce weight or to prevent frailty. Excessive physical exercises can cause or exacerbate urinary incontinence symptoms in women. By contrast, a regularly performed appropriate exercise may alleviate the symptoms of urinary incontinence.
Thus, although several studies on physical activity related on the onset of urinary incontinence have been reported, it is still unclear how physical activity affects the severity of urinary incontinence or the quality of life related to urinary incontinence.
We believed that the intensity and quantity of physical activities in daily life are related not only to the onset of symptoms of urinary incontinence but also to the severity of urinary incontinence and even the quality of daily life related to urinary incontinence. It was hypothesized that people with lower strength and amount of physical activity have higher severity of urinary incontinence and lower quality of daily life related to urinary incontinence. This study aimed to clarify the relationship between physical activity and the severity of urinary incontinence and the quality of life and physical activity as a result of urinary incontinence.
Study design, materials and methods
From July through September in 2018, we provided a urinary incontinence prevention program to women in the neighborhood. Twenty subjects participated in the program. For physical activity, Steps, Metabolic equivalents (METs: intensity of physical activity), Exercise (amount of physical activity) were measured for one week continuously using an activity meter (Active style Pro manufactured by OMRON). Steps and Exercise calculated as the average per day by dividing the total number by the number of days. METs was calculated as the average value per unit time by dividing the total number by time. The QOL related to urinary incontinence was analyzed using the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF). In order to clarify the relationship between severity of urinary incontinence and physical activity, Spearman's rank correlation coefficient was used for analysis.
The number of subjects were 20, with an average age of 67.6 years (SD 10.1), body mass index (BMI) of 22.2 kg / m 2 (SD 4.4), number of deliveries 1.7 times (SD 1.0), ICIQ- SF of 4 points (0 - 15). Steps averaged 6820.4 ± 2418.5 steps per day, METs averaged 1.6 ± 0.2 per unit time, Exercise 5.5 ± 2.0 Ex per day. The total points of ICIQ-SF showed a negative correlation with Steps (-0.49), METs (-0.47) and Exercise (-0.52), and the frequency of urine leakage in sub-items was Steps (-0.40), METs (-0.49), Exercise (-0.53). The amount of urine leakage was not related to Steps, but METs (-0.5) and Exercise (-0.47) showed a negative correlation. In addition, the influence of urinary leakage on daily life showed a negative correlation only with Steps (-0.51; Table 1).
Furthermore, in relation to physical activity and age or BMI, negative correlation was found only between Exercise and age, and no other relationship was recognized (Table 2).
Interpretation of results
Based on the results of this study, it can be said that the intensity and quantity of physical activities are high in the subjects with mild urinary incontinence. Physical activity is affected to the onset of incontinence as well as the severity. The quality of daily life affected to urinary incontinence was only related to the number of steps, and not related to the strength or quantity of physical activity. These data indicate a decrease in the quality of daily life, because physical activity prevents deterioration of (but improves) quality of life, while urinary incontinence decreases the opportunity for activity (step count) and thus deteriorates quality of life.
Previous studies have shown that exercise slightly reduce the risk of urinary incontinence in healthy women , and that weight control and prevention of obesity play an important role to reduce the risk of urinary incontinence (1). By contrast, in the present study, although the relationship between the severity of urinary incontinence and physical activity was recognized, there was no association between physical activity and BMI, which is an indicator of obesity, and thus, weight control and prevention of obesity by doing physical exercise had no effect on the severity of urinary incontinence. As another factor, it is suggested that intraperitoneal pressure by physical exercise result in simultaneous contraction (and strengthening) of pelvic floor muscle tissue (2). In the present study, since the muscle strength of the pelvic floor muscles was not evaluated, this factor cannot be determined. We speculated that the muscle strength of the pelvic floor muscles was maintained in the subjects with better physical activity.
The limitation of this study is that we could not clarify whether physical activity prevents urinary incontinence or urinary incontinence limits physical activity. We would need to clarify this by randomized intervention studies.