My name is Suzanne, and I was diagnosed with Addison's Disease in 2017. I immediately joined the ADSHG in the hope that I could understand more about this rare disease, meet other people who have it and learn as much as I could from them to work out how to live with it, how to help myself and keep safe.

I read about circadian and ultradian rhythms and began to question my hydrocortisone doses;

  • How quickly is it absorbed?
  • How long does it take to clear?
  • How high do the different quantities in doses peak?
  • Am I taking the correct amount at the correct times?
  • How can I mimic the natural circadian rhythm so that I do not have periods of consistent over- or under-replacement?
  • What, apart from illness, injury and emotional trauma, could cause a need for me to up-dose, what about a stressful day at work, or a high-intensity workout?

I began to realise that a one-off random blood test was not going to be of much use to answer these questions. Even a day curve, although helpful, is not necessarily representative of an average day, I mean, who usually spends a day in hospital waiting for hourly blood tests?

Participation in the 2021 ULTRADIAN Study

It was via the ADSHG online community forum that I learned about the ULTRADIAN Study at Bristol University and decided to offer myself as a participant.

The purpose of the study was to take samples from volunteers with healthy adrenal glands, plus those with Addison’s, to measure and compare the amount of cortisol in the body throughout a 24-hour period. The U-RHYTHM used in the ULTRADIAN study measures ‘free’ hormones, whereas the blood tests most of us routinely have measure the total amount of hormones circulating, including those bound to proteins.

A microdialysis probe, which has tiny holes along it, is inserted just under the skin of the stomach into the adipose tissue. This is connected to a pump and collects a sample every 20 minutes. The device is worn for 27 hours in which you can go about your normal day. I was asked to keep a diary of the activities I did during the day, what time I went to bed and got up and what and when I ate. 

I found the results very interesting; compared to healthy individuals, my levels were a little high, suggesting I am probably taking a bit too much hydrocortisone. I learned that the amount of time it takes for hydrocortisone to peak and clear in my body is different depending on the time of day it is taken. Back in 2018 (when the sample was taken), my adrenals were still producing cortisol (although a small amount) in the early hours of the morning.   

The following year, I was approached by the ULTRADIAN team and AVROTROS, a Dutch TV broadcaster, who were making a documentary about hormones and I was asked if I would be willing to take part. Even though it is not something I would normally do, the filming was fun; I spent hours talking to the team and was a little shocked by what was used in the documentary. I think that it is so important for us to offer ourselves to the world of research in order to develop a better understanding of how the body works, how to prevent illnesses and develop better treatments for the future. You can watch AVROTROS' documentary online here.

My hope for the future

This way of monitoring hormones gives a much more detailed account of what is happening within our bodies in our ‘normal’ lives and could lead to more accurate replacement therapy, not only for those of us with Addison’s, but I do believe it can be used to measure many different hormones and monitor several other conditions.

It would be amazing if this could eventually be a routine yearly test for us all to have and maybe to provide us with answers to many of our questions and a more tailored treatment plan."

During the test, I really wanted to go to the gym to see how much cortisol I used, but sadly was not allowed and, as I do not live in Bristol, I did not go to work, so my day was spent sightseeing in Bath, with no stressful moments to observe.


For more information on ULTRADIAN and U-RHYTHM, read:

2021 & 2023: Behind the Research: the U-RHYTHM System

2026: U-RHYTHM Receives 20k boost from the ADSHG

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