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The 24-hour pad test in continent women and men: normal values and cyclical alterations
E Karantanis1, R O'Sullivan, K H Moore
1Pelvic Floor Unit, St George Hospital, University of New South Wales, Sydney, Australia.
Objective:
To obtain control values for the 24-hour pad test in a wide age range of continent women using accurate weighing scales and to compare the results obtained from pantyliners and pads in women and men.
Design:
Prospective anonymous study.
Setting:
A Sydney Tertiary Urogynaecology Unit.
Population:
One hundred and forty continent women and 14 continent men.
Methods:
A 24-hour pad test was performed in 120 continent women of widely varying ages, in whom hormonal status and exercise habits were documented. These continent women wore a standardised pantyliner for 24 hours and a high precision beam balance (accuracy 0.1 g) was used to measure the loss on the pad. To assess any variation in pad weights with differing pads, 20 female volunteers undertook the 24-hour test firstly with pantyliners then larger pads. To understand evaporative qualities of the two types of pads, one male wore each type of pad, instilled with 5 mL normal saline for eight hours overnight. Furthermore, to understand the contribution of vaginal secretions, a group of male volunteers performed a 24-hour test with pantyliners followed by pads.
Main Outcomes Measures:
Pad weight, with regard to hormonal status, exercise, pad type and gender. The median age of subjects was 48 (interquartile range [IQR] 32-60), with a median pad weight gain of 0.3 g (IQR 0.2-0.6; 95th centile 1.3 g). Subgroup analysis showed no significant trends for pad loss in relation to menopause status, use of hormone replacement therapy or hormonal contraception and exercise status during the 24-hour period. Control values for pantyliners were not significantly different from those for continence pads. In addition, normal values in 14 males showed similar results, regardless of pad type.
Conclusions:
The response rate of 39% might limit the applicability of the results. However, our finding that women lose only 0.3 g of vaginal secretions in 24 hours is much lower than previously reported. This might arise from the use of a highly accurate beam balance and the recruitment of a large sample of women with widely varying ages. This result might lower the threshold for objective diagnosis of urinary incontinence and alters the pad test definition of 'cure'.
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