Desmopressin

ANAHEIM, CALIF. -- Oral desmopressin is useful in the treatment of nocturia in men and women, according to two studies presented at the annual meeting of the American Urological Association.

A third study indicated that the pathogenesis of the disorder in the elderly can be accounted for by a lower functional bladder capacity or an age-related increase in nocturnal urine volume.

Nevertheless, desmopressin should be used only after potential behavioral controls for nocturia have failed and after treatable causes of nocturia have been eliminated, said Dr. Jeffrey P. Weiss of the Urocenter of New York.

Dr. Weiss presented one of the studies, a randomized, placebo-controlled trial involving 146 men with nocturia, which was defined as awakening to void more than two times per night.

The proportion of patients with at least a 50% reduction in the number of voids per night was 34% for the desmopressin group and 3% for the placebo group.

Nocturnal urine output decreased significantly in the group receiving the drug, and the mean duration of the initial period of sleep in this group was 83 minutes longer than it was in the placebo group. Overall, 29 (35%) of the patients who received desmopressin got more than 5 hours of unbroken sleep, compared with only 1 patient (2%) in the placebo group.

Dr. Philip van Kerrebroeck of University Hospital, Maastricht, the Netherlands, reported on a similar study involving 142 women. Among women who received the drug, 46% had at least a 50% reduction in the number of voids, compared with 7% of those in the placebo group.

Nocturnal urine output also decreased significantly among women taking desmopressin, and the mean duration of first sleep in this group was 91 minutes longer than in the placebo group. Overall, 24 (33%) of the women in the treatment group got more than 5 hours of unbroken sleep, compared with only 4 patients (6%) in the placebo group.

Asa Rembratt reported on questionnaires returned by 2,081 Swedish men and women over the age of 65. She compared 117 people who were awakened at night by the need to urinate and 109 people with normal urinary and sleep patterns.

The ratio between nocturnal urine production and functional bladder capacity most clearly differentiated nocturics from nonnocturics, said Ms. Rembratt, a clinical research associate at Ferring Pharmaceuticals, which makes desmopressin (DDAVP) and which supported all three studies.

In an interview, Dr. Weiss advised questioning patients about their intake habits before prescribing medication for nocturia. "If somebody is having three cups of tea or two or three beers at night, you just give them sound advice [to reduce consumption before bed]. If they're drinking water over and above what their thirst requires and they don't have a history of kidney stones, then tell them it's not necessary to drink so much water."

Once excessive intake is eliminated as a cause, Dr. Weiss probes for evidence of congestive heart failure. He also asks patients to keep a 24-hour voiding diary. If they have polyuria, he considers a diagnosis of diabetes mellitus or diabetes insipidus.

Check urinary flow to make sure they don't have an obvious lower urinary tract abnormality that could be corrected, he continued. "Looking at the volume, you could tell them to wear compressive lower-extremity garments if they have edema. You can tell them to move their Lasix out from first thing in the morning to the early afternoon. ... And you can also encourage them to take an afternoon nap in the supine position. ... Failing that, we can give them desmopressin."

COPYRIGHT 2001 International Medical News Group
COPYRIGHT 2001 Gale Group