The relative contributions of motor, sensory, and biomechanical dysfunctions to impaired voiding performance independent of outlet obstruction associated with aging remain to be elucidated.

The pad test is clearly underutilized. Well-designed studies providing level one evidence are lacking. Numerous variations in how the test is performed by individual urologists make the evaluation of published literature difficult. Future research goals should include randomized studies leading to establishment of optimal protocols of testing for clinical research and daily care.

The prevalence of urinary symptoms increases with age and is a significant source of distress, morbidity, and expense in the elderly. Recent evidence suggests that symptoms in the aged may result from sensory dysfunction, rather than abnormalities of detrusor performance. Therefore, we employed a pressure/flow multichannel urethane-anesthetized mouse cystometry model to test the hypothesis that in vivo detrusor performance does not degrade with aging. Secondarily, we sought to evaluate sensory responsiveness to volume using pressure-volume data generated during bladder filling. Cystometric data from 2-, 12-, 22-, and 26-mo-old female C57BL6 mice were compared. All 2- and 12-mo-old mice, 66% of 22-mo-old mice, and 50% of 26-mo-old mice responded to continuous bladder filling with periodic reflex voiding. Abdominal wall contraction with voiding had a minimal contribution to expulsive pressure, whereas compliance pressure was a significant contributor. Maximum bladder pressure, estimated detrusor pressure, detrusor impulse (pressure-time integral), as well as indices of detrusor power and work, did not decrease with aging. Bladder precontraction pressures decreased, compliance increased, and nonvoiding contraction counts did not change with increasing age. Intervoid intervals, per-void volumes, and voiding flow rates increased with age. Calculations approximating wall stress during filling suggested loss of bladder volume sensitivity with increasing age. We conclude that aging is associated with an impaired ability to respond to the challenge of continuous bladder filling with cyclic voiding, yet among responsive animals, voiding detrusor contraction strength does not degrade with aging in this murine model. Furthermore, indirect measures suggest that bladder volume sensitivity is diminished. Thus, changes in homeostatic reserve and peripheral and/or central sensory mechanisms may be important contributors to aging-associated changes in bladder function.

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Objective To evaluate the use of the home pad test in the management of patients with urinary dysfunction with reference to feasibility, normal data, reproducibility, compliance and accuracy when compared to video urodynamics. Design A prospective study to determine 1. the accuracy of weighing pads by healthcare workers compared to weighing by patients with a spring balance; 2. the effects of evaporation; 3. the pad weight increase in continent women; 4. the compliance over 194 tests in terms of acceptability and feasability; 5. the reproducibility in 112 women for the 24 h and 48 h tests, 6. the comparison with video urodynamic studies in 149 patients. Setting A London teaching hospital. Main outcome measures Coefficient of variation and mean deviation analysis were employed to determine the accuracy of measurement. Percentage changes in standardised wet pad weights over a period of 8 weeks were used to determine the rate of weight loss due to evaporation. The percentage of patients completing the test satisfactorily was documented. The increase in the weights of all the pads worn during the test period was measured in continent volunteers and incontinent patients. Video urodynamic diagnoses were used as the Gold Standard for comparison. Results Twelve perineal pads were weighed by 15 healthcare workers with a resulting coefficient of variation equal to 1.55% (standard error = 0.09%). The mean deviation between patient‐measured pad weights and staff‐measured weights was 49% (SD = 132%). Pads wetted with saline showed no difference in weight after 1 week and less than 5% change in weight after 8 weeks, with the upper 95% confidence limit of less than 10% loss. The mean pad weight increase over 48 h in continent women was 7.13 g (SD = 4.32 g) giving a 95% upper confidence level of less than 15 g. Compliance was reasonably high with 161 (83%) carrying out the test perfectly. Test‐retest analysis of the 24 h and 48 h tests showed a strong relationship with correlation coefficients of 0.90 and 0.94 respectively. The reproducibility was also good, with differences as a percentage of the mean between the first and second test being 6.9% and 1.6% for the 24 h and 48 h tests respectively. There was good concordance when the urodynamic study data was compared with pad weight data in terms of incontinence compared with no incontinence (kappa = 0.65), but a high false positive rate was detected for the pads. When eight of these patients with a false positive pad test had repeat video urodynamic studies, six were found to have detrusor instability on the second study. Conclusions The home pad test combined with frequency volume chart documentation is an easy test to perform. It is quite robust and reasonably reproducible. This test should be added to complement the routine urodynamic tests and may have a role in detecting occult detrusor instability.