From Lewis S Blevins, Jr MD –
One hundred ninety-eight persons completed our survey on diabetes insipidus. Approximately two-thirds of respondents reside in the United States whereas 14% live in Great Britain, 7% live in Australia, 5% in Canada, and the remainders reside in nine different countries.
One third of respondents were in the 35 to 44 age range and the results were normally distributed with 10% in the 15 to 24 age group and 9% in the 55 to 64 age group. Fifteen percent of persons completed the survey for a child under 18 years of age.
A majority of persons, 55%, had diabetes insipidus for greater than six years duration, while 12% of respondents had been diagnosed within the past year.
An overwhelming majority of persons had diabetes insipidus due to either hypothalamic or pituitary disorders. Only 3% had nephrogenic diabetes insipidus due to kidney resistance to vasopressin.
As expected, the causes of diabetes insipidus included pituitary tumor, pituitary surgery, pituitary stalk lesions, Craniopharyngioma, Langerhans Cell Histiocytosis, traumatic injury to the pituitary or pituitary stalk, heritable genetic conditions, Germinoma, birth defects, autoimmune inflammatory disorders, meningitis, and unknown causes.
These disorders are considered to be the most common causes of diabetes insipidus. Sarcoidosis and other infiltrative disorders, tuberculosis, fungal infections, metastatic cancer (Breast, lung, melanoma) are other known causes of diabetes insipidus.
A majority of respondents (93%) reported using DDAVP. Surprisingly, 61% reported using oral DDAVP, 26% reported using DDAVP nasal spray, 4% use the dDAVP solution administered intranasally using a rhinal tube, and 5% use injectable DDAVP.
In my practice, most patients use the DDAVP nasal spray.The tablets seem to work particularly well for younger and older persons. They are also convenient when traveling. My patients who use the tablets report variable effects. This is probably due to the fact that DDAVP is destroyed by stomach acid. Stomach acid varies according to time of day and meal ingestion and this might lead to more or less degradation, and either less or more absorption, respectively, depending on circumstances. I do have occasional patients who require DDAVP by injection. Here’s a general rule of thumb: 1 µg of DDAVP injected is equivalent to 10 µg intranasally, and is equivalent to about 100 to 300 µg taken orally. These “conversion rates” can be used in patients who are transitioning from one form of DDAVP to another because of various circumstances such as illness, inability to take medications by mouth, etc.
I must admit that I am surprised a majority of respondents indicated they did not know their 24 hour urine output. I feel that it is a good idea to have an approximate idea of how much urine you make every day if you have diabetes insipidus. This information can be useful to your physicians when deciding on treatment, such as during hospitalization, and can assist you in determining whether your treatment is sufficient. Polyuria, the term meaning excessive urine flow, is defined as more than 30 mL of urine per kilogram of body weight. For the average adult, weighing 70 kg, roughly 165 pounds, this is about 2.1 L. Anything over that would be excessive. The calculation is important to gauge whether or not a small adult or even a child is appropriately treated. I have found that most patients do well tolerating a urine output that averages 3 to 3.5 L per 24 hour period. Interestingly, some respondents had urine outputs of over 20 L per day at the time of diagnosis. This is not surprising and represents “how bad” it can be with complete full-on or full-blown diabetes insipidus.
Forty Three percent of respondents report Nocturia – or urination that occurs during the nighttime – two or more times per night. Fifteen per-cent of our group urinate four or more times each night.
Frankly, in my opinion, one of the most important goals of treatment in patients with diabetes insipidus is to control nocturia to permit sleep. Thus, if you are awakening regularly to urinate, I would suggest discussing this with your physician and consider revising your approach to treatment to permit a full nights rest.
Sixty five percent of the survey group reported allowing breakthrough excessive urination before taking a subsequent dose of DDAVP. This approach is highly recommended and will avoid overtreatment and also assist in determining whether your diabetes insipidus has resolved over time following surgery or resolution of some other disease process.
Hyponatremia was reported during treatment by 19% of respondents. About half of persons were fairly clear that they had not ever had hyponatremia during treatment.
In my opinion, hyponatremia is worse than uncontrolled diabetes insipidus and should be avoided. This can be achieved by allowing breakthrough polyuria before subsequent doses or at least twice a week. Also, it is important to avoid drinking excessive amounts of water such as might take place while dieting, during vigorous exercise, as instructed to “drink plenty of fluids” by a physician when sick with the flu, keg parties, IV fluids during chemotherapy during hospitalization for other reasons, etc.
Interestingly, 36% of respondents reported that their DDAVP dose increases during a cold or other illnesses while 20% reported that the DDAVP dose decreases and 44% of persons indicated that their dose requirement did not change. Factors report to increase the DDAVP dose requirement included: stress, alcohol intake, caffeine intake, nonspecific illnesses, upper respiratory illnesses and nasal congestion, seasonal allergies with nasal congestion, hot weather, exercise, menstrual cycle, pregnancy, addition of hydrocortisone to treatment regimen, high altitude, initiation of growth hormone replacement, gastritis, diarrheal illness, and cold weather.
Some people reported the following cause is associated with a decrease to DDAVP dose requirement: alcohol intake, inactivity, taking omeprazole, nonspecific illnesses, opiate ingestion, hot weather, cold weather, weight loss, and noncompliance with steroid medications.
Only about one half of patients wear a medical or ID bracelet indicating that they have diabetes insipidus.
Strongly recommend that you consider obtaining and wearing a bracelet that indicates that you not only have diabetes insipidus but that you take DDAVP. You should also list other hormone deficiency states, and, especially, if you have adrenocortical insufficiency and take steroids. This identification could save your life if you are injured or sick and unable to provide your medical history to treating physicians.
Lastly, our survey asked respondents to share something important learned as a patient with diabetes insipidus. The comments were nothing less than astounding and exceeded our expectations; they are gold! Rather than recapitulate them here we will share them on our Facebook page periodically and will collate them and put them on our website for future reference.
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