NEW YORK (Reuters Health) – In adults with overactive bladder and nocturia, treatment with solifenacin, may improve quality of sleep and sleep-related quality of life by decreasing the number of overnight trips to the bathroom and increasing the amount of urine voided per trip.

Solifenacin (Vesicare; Astellas Pharma) is a urinary antispasmodic of the antimuscarinic class approved by the US Food and Drug Administration for use in adults in 2005.

The new findings stem from a secondary exploratory analysis of 962 Japanese men and women with overactive bladder and nocturia who participated in a randomized, controlled trial evaluating the efficacy of solifenacin (5 of 10 milligrams) versus placebo for nocturia.

A total of 332 subjects received placebo, while 321 and 309 received solifenacin 5 and 10 mg, respectively. Participants reported voiding at least once during the night at baseline and completed efficacy and quality of life assessments at baseline and 12 weeks when treatment ended.

In the May 14 online issue of the Journal of Urology, Dr. Osamu Yokoyama from University of Fukui and colleagues report that the 10-mg dose of solifenacin led to a decrease in nocturia episodes by 0.46 episodes (P = 0.0449). The decrease in nocturia episodes was not statistically significant with the 5-mg dose.

Both the 5- and 10-mg dose significantly increased nighttime volume voided per micturition by 30 and 41 milliliters, respectively (P = 0.0033 and P < 0.0001, respectively).

With solifenacin 5 and 10 mg, the amount of undisturbed sleep time increased by about 1 hour, compared with about a half hour with placebo.

“To our knowledge,” note the researchers, “our study represents the first assessment of the effect of an anticholinergic on hours of undisturbed sleep.” It’s been shown, they point out, that hours of undisturbed sleep has a “more significant impact” on sleep quality than the number of nocturia episodes.

Significant improvement in sleep-related quality of life was also evident in those taking solifenacin (P < 0.001 for each dose).

Among lower urinary tract symptoms, nocturia has the greatest impact on patient quality of life, the researchers note in their report. “Few studies to date show that anticholinergic therapy improves quality of sleep, particularly sleep-related quality of life,” they point out.

Nonetheless, they say their findings “must be interpreted with caution due to the exploratory nature of the analysis.”

The analysis was supported by Astellas Pharma Inc.

J Urol 2011