Urinary quality of life after prostatectomy or radiation for localized prostate cancer: a prospective longitudinal cross-cultural study between Japanese and U.S. men.
OBJECTIVE
To compare the evolution of urinary dysfunction and associated distress (bother) during the first 2 years after radical prostatectomy (RP) or external beam radiation therapy (EBRT) between Japanese and U.S. men with localized prostate cancer.


METHODS
A total of 477 Japanese men and 385 U.S. men with localized prostate cancer who underwent RP or EBRT participated in paired longitudinal outcomes studies. We evaluated urinary control and distress using the University of California-Los Angeles, Prostate Cancer Index and urinary irritation/obstruction using the American Urological Association Symptom Index (AUASI) before and 1, 2 to 3, 4 to 6, 8, 12, 18, and 24 months after treatment. We used general linear mixed modeling adjusting for subject characteristics to assess changes in these domains.


RESULTS
Multivariate analyses revealed a nonlinear trend of recovery and an interaction between this trend and country with regard to urinary function (control) and bother after RP (both P <0.0001). Among the men who received EBRT, the recovery trend of AUASI and urinary bother also differed significantly by country (both P <0.0001).


CONCLUSIONS
Japanese and U.S. men differed in their patterns of urinary recovery up to 24 months after curative therapy for localized prostate cancer.
Namiki
Shunichi
S
Department of Urology, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California 90095-1738, USA.
Kwan
Lorna
L
Kagawa-Singer
Marjorie
M
Terai
Akito
A
Arai
Yoichi
Y
Litwin
Mark S
MS
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003431:Cross-Cultural Comparison; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011468:Prostatectomy / Q000009:adverse effects*; D011471:Prostatic Neoplasms / Q000532:radiotherapy* / Q000601:surgery*; D011788:Quality of Life; D011878:Radiotherapy / Q000009:adverse effects; D014481:United States; D014555:Urination Disorders / Q000209:etiology*