Nongenetic factors associated with stress urinary incontinence.
OBJECTIVE
To explore the role of hereditary and environmental factors on the development of stress urinary incontinence in a large cohort of identical and nonidentical twins.


METHODS
This is a large, population-based, classic twin study of twin sisters recruited to complete a health survey at the world's largest annual twins festival during 2003-2008. Concordance rates were calculated and structural equation models were used to estimate the contribution of genetic effects compared with environmental factors toward the development of stress urinary incontinence.


RESULTS
Eight hundred eighty-two twin sister pairs (n=1,764), including 765 identical and 117 nonidentical twin sister pairs, completed the questionnaires. Sequential structural equation modeling revealed that common environmental factors contributed 77.6% (95% confidence interval [CI], 41.4-83.8; P<.001) of the variance and unique environmental factors contributed 20.9% (95% CI, 15.8-26.7; P<.001) of the variance. The effect of genetics was not statistically significant at 1.49% (95% CI, 0.0-38.8; P=.46).


CONCLUSIONS
Female stress urinary incontinence is more a consequence of environmental risk factors than heredity. This epidemiologic insight should be considered in preventive health efforts.


METHODS
II.
From the Division of Urogynecology, NorthShore University HealthSystem, The University of Chicago Pritzker School of Medicine, Evanston, Illinois; the Division of Urogynecology, ProHealth Care Women's Center, Medical College of Wisconsin, New Berlin, Wisconsin; the Center for Clinical Research Informatics, NorthShore University HealthSystem, Evanston, Illinois; and the Department of Obstetrics and Gynecology, John Stroger Cook County Hospital, Chicago, Illinois.
Aimee
A
Nguyen
Sarit O
SO
Aschkenazi
Peter K
PK
Sand
Hongyan
H
Du
Sylvia M
SM
Botros
Tondalaya L
TL
Gamble
Robert
R
Kuo
Roger P
RP
Goldberg
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D014481:United States / Q000453:epidemiology; D014550:Urinary Incontinence, Stress / Q000453:epidemiology / Q000235:genetics*; D055815:Young Adult
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