Incontinence Due to Pelvic Floor Issues Affects Women With DM1
60% of myotonic dystrophy type 1 patients in study report leaky bladder
Pelvic floor disorders, including urinary and anal incontinence, are common in women with myotonic dystrophy type 1 (DM1) and a cause of significant distress, according to a recent study in Canada.
“This study highlights the importance of screening these symptoms in a clinical setting and will help develop interventions to adequately treat these symptoms, taking into account the characteristics of the disease,” its researchers wrote.
Ways of addressing urinary incontinence — reported by 60% of the women in this study — “should be explored due to the high prevalence of this disorder,” the team added.
The study, “Prevalence of urinary incontinence and other pelvic floor disorders in women with myotonic dystrophy type 1,” was published in the journal Neuromuscular Disorders.
Pelvic floor muscles help in controlling bowels and the bladder
DM1 is caused by mutations in the DMPK gene, leading to the hallmark symptom of myotonia — when muscles are unable to relax after a contraction. Like other forms of muscular dystrophy, DM1 also is marked by progressive muscle weakness and wasting.
Pelvic floor muscles are among those that can be affected in DM1. Located in the pelvis, these muscles help control the bowels and bladder, as well as the uterus and vagina.
Their dysfunction can lead to a range of debilitating symptoms, including difficulty controlling the bowel and bladder. Yet, the presence of such pelvic floor disorders in women with DM1 have not been well-explored.
A research team aimed to document the prevalence, characteristics, and impacts of pelvic floor disorders among women with DM1 seen at the Saguenay–Lac-St-Jean neuromuscular disease clinic, in Quebec, between March and October 2021.
A total of 80 women, ages 23 to 78 (mean age of 47), from the clinic’s patient registry were included in the study. Nearly half (43.8%) had an adult or late adult-onset form of DM1.
Participants underwent interviews, usually by phone (96.3%), to assess for the presence of pelvic floor disorders and their effects on daily life. Interviews included a set of validated questionnaires and were conducted by a physical therapist with expertise in pelvic floor disorders.
Among these women, 48 (60%) reported urinary incontinence, also known as overactive or leaky bladder, as assessed by the International Consultation Incontinence Questionnaire ± Urinary incontinence short form (ICIQ-UI-SF).
Leaks occurred at least once a day for 18.8% of them, most often during physical activities or coughing or sneezing that places pressure on the bladder (stress incontinence; 47.5%), or as a result of a sudden urge to urinate (38.8%).
“DM1 can cause changes in the skeletal muscles, like atrophic fibres, fat infiltration, and fibrosis,” the researchers wrote. “These changes could explain the high prevalence of urinary incontinence in women with DM1.”
Women with a late adult form of DM1, on average, had less severe urinary incontinence than those with an infantile, juvenile or adult onset. Moreover, urinary incontinence was more severe for women who had given birth to multiple children than for women who had not given birth.
Risk of anal incontinence rises with infantile and juvenile-onset DM1
A range of other pelvic floor disorders also were noted, assessed using the Pelvic Floor Disorder Inventory (PFDI) and the Pelvic Floor Impact Questionnaire short form (PFIQ-SF).
The most common pelvic floor disorders, identified in more than half of participants, included abdominal pain before a bowel movement, anal or urinary incontinence, bowel urgency, increased nighttime urinary frequency, and frequent urination.
People with infantile and juvenile-onset DM1 were at a higher risk of anal incontinence than those with late adult DM1.
Overall, women reported a “high degree of bother or distress” related to their symptoms, particularly colorectal-anal symptoms.
Colorectal-anal symptoms also had the highest impact on social participation and emotional well-being. However, patients did not specifically feel that their reduced participation in daily life was due to these disorders, but rather to muscle weakness and balance problems associated with having DM1, the researchers noted.
In general, study findings demonstrate a higher prevalence of pelvic floor disorders in women with DM1 compared with rates identified in previous studies of healthy women.
Rates of these symptoms potentially could be higher than reported in the study, the researchers noted, as hesitancy to talk about sensitive symptoms could affect their reporting in direct interviews.
Still, “this was a first step to documenting the importance of these problems in this population, and more studies are needed to document pelvic floor disorders,” the researchers wrote.