The effect of age on lower urinary tract function: a study in women.
OBJECTIVE
To identify age-associated changes in female lower urinary tract function across a wide age spectrum, controlling for detrusor overactivity (DO).


METHODS
Secondary analysis of a cross-sectional study of DO and aging. Eligible volunteers were stratified by age group and presence of DO.


METHODS
Community-based volunteers, evaluated in research laboratory.


METHODS
Eighty-five ambulatory, nondemented, community-dwelling female volunteers, with and without bladder symptoms suggestive of DO, recruited by advertising, mean age 54 (range 22-90); 75% Caucasian, 21% African American.


METHODS
Comprehensive assessment included bladder diary, uroflowmetry, and detailed videourodynamics. Predefined urodynamic and diary variables were examined for association with age and DO. Mean values of these variables were calculated for subgroups aged 20 to 39, 40 to 59, and 60 and older (14 subjects > or =70).


RESULTS
Maximum urethral closure pressure, detrusor contraction strength, and urine flow rate declined significantly with age (P<.001, P<.001, P=.006, respectively), regardless of whether DO was present. Most elderly individuals continued to empty their bladder almost completely, with normal voiding frequency. Mean number of nocturnal voids was less than one in all age groups. Bladder capacity did not decrease with age (mean 522 mL in oldest group) but was smaller in subjects with DO. Bladder sensation diminished significantly with age (P<.001) but was stronger in subjects with DO.


CONCLUSIONS
Female bladder and urethral function appear to deteriorate throughout adult life, whether DO is present or not. Specifically, detrusor contractility, bladder sensation, and urethral pressure decline. The common belief that bladder capacity shrinks with age may be related to DO rather than to aging itself.
Bethanien-Krankenhaus, Geriatric Center of the University of Heidelberg, Heidelberg, Germany. mpfisterer@bethanien-heidelberg.de
Mathias H-D
MH
Pfisterer
Derek J
DJ
Griffiths
Werner
W
Schaefer
Neil M
NM
Resnick
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008875:Middle Aged; D009119:Muscle Contraction; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D001743:Urinary Bladder / Q000503:physiopathology*; D014549:Urinary Incontinence / Q000453:epidemiology / Q000209:etiology; D014552:Urinary Tract Infections / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D014563:Urodynamics / Q000502:physiology