Overactive bladder linked to sleep apnea in women

The research, presented Monday (Sept. 3, 2012) at the European Respiratory Society's Annual Congress in Vienna, has provided new evidence suggesting a connection between the two conditions.

Overactive bladder syndrome is characterised by an increased frequency to urinate along with incontinence and frequent awakening periods during night time to use the toilet (nocturia). The need to urinate during the night is also a common symptom of sleep apnea, but little research has been carried out to investigate any links between the two conditions.

Researchers from the Hospital del Mar in Barcelona, Spain, analysed 72 female patients referred to a sleep disorders clinic with suspected sleep apnea. All patients completed a questionnaire asking them about four symptoms associated with their bladder control; urgency and frequency of urination, incontinence and nocturia. They were also asked to rate their discomfort with each of these symptoms.

The results from the questionnaires were then analysed and rated on two scales in order to evaluate both the severity of symptoms and discomfort for each of the four variables, scoring from 0 to 3 for each of these four items.

The analysis showed that 62 of the women were diagnosed with sleep apnea. The people within this group showed significantly higher scores for the prevalence of symptoms associated with bladder control and their discomfort with these symptoms.

Within the group diagnosed with sleep apnea, the symptoms were rated a median average score of 5, out of a possible total of 12, compared to a score of 3 in the group not diagnosed with the condition. The median average score for discomfort with bladder control symptoms was 4 out of 12, compared with a score of 1 in the group of women who weren't diagnosed with sleep apnea.

Lead author, Núria Grau from the Hospital del Mar in Spain, said: "Overactive bladder has a prevalence of 16% among people over 40 years in Europe and it is a difficult condition to live with, affecting a person's quality of life. The findings of this study provide evidence that bladder control could be linked to sleep apnea, although we do not know whether one of the conditions causes the other.

"The next step in our research is to investigate the role of continuous positive airway pressure therapy in these patients and its impact on the symptoms of overactive bladder."