Circadian Function and Cardio-metabolic Risk in Adrenal Insufficiency

Study Overview
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Brief Summary
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The purpose of this study is to compare cardio-metabolic risk, glucose tolerance, and night time blood pressure between healthy control subjects and patients with adrenal insufficiency. No intervention will be administered and the study is observational only.

Detailed Description
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We propose to use a case control design to test the main hypothesis that as compared to healthy control subjects matched for sex, age, adiposity and race/ethnicity, patients with adrenal insufficiency, whether primary or secondary, have disturbances of the circadian system that are associated with high day to day variability of sleep time as well as elevated markers of cardio-metabolic risk, including abnormal oral glucose tolerance and reduced nocturnal blood pressure dipping. A secondary hypothesis of the study is that adrenal insufficiency patients on a replacement regimen (as part of their standard of care ongoing treatment) that results in daytime cortisol profiles approximating the normal diurnal variation will have better cardio-metabolic function than adrenal insufficiency patients who have grossly abnormal cortisol profiles.

Official Title
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Circadian Function and Cardio-metabolic Risk in Adrenal Insufficiency: a Case Control Study

Conditions
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Adrenal Insufficiency

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Primary or secondary adrenal insufficiency, Healthy matched controls, acute or unstable health conditions age 18 or older Exclusion Criteria: Diabetes, Tertiary adrenal insufficiency

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Healthy Controls<br>Matched by age, race, gender and BMI to adrenal insufficiency subjects | |
| Adrenal Insufficiency Patients<br>Eligible patients will have either primary adrenal insufficiency or secondary adrenal insufficiency and will be age 18 and older. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| day to day variability of sleep timing over 1 week of recording | On each day, the midpoint (time in hours and minutes) of the sleep period will be calculated and the variability over 1 week will be quantified by the standard deviation | day 1 to day 7 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| nocturnal blood pressure dipping | a 24-h recording of blood pressure will be conducted in the laboratory with concurrent sleep recording. Dipping will be calculated as the difference between the daytime mean and the nighttime mean | day 8 to 9 | 
| oral glucose tolerance | A 3-h 75g oral glucose tolerance test will be performed in the laboratory after an overnight fast. Glucose tolerance will be quantified by the total area under the glucose curve over the 3-hour period of sampling. | day 11 to 12 |