Table 1.
Detailed clinical procedures and sampling time point for hypertensive patients with raised plasma ARRs who were admitted for SSST
| Time Point | Admission Day | Day of Posture Responsiveness Testing (Day 0) | Day of SSST (Day 1) |
|---|---|---|---|
| 6:00am | 1. Urine for uEVs was collected after getting up (post-test spot urine and uEV for the current study) | ||
| 7:00am | Home 24-hour urine test started | 1. Home 24-hour urine test ended 2. Blood was collected after overnight recumbency (results were adopted as baseline blood measurements for the current study) 3. Urine for uEVs was collected after bleeding (baseline spot urine and uEV for the current study) |
2. Before SSST, blood was collected 30 minutes after assuming a seated posture (results were adopted as post-test blood measurements for the current study) 3. SSST commenced at 8:00am |
| 10:00am | 4. Blood results at 7:00am were available For the current study, if plasma [K+] <4.0 mmol/L, participants were given sufficient oral KCl up to Q6h to achieve as close to 4.0 mmol/Las possible by the next morning at 7:00am 5. Blood was collected after 3 hours of upright posture |
||
| 12:00pm | SSST completed | ||
| 1:00pm | Participants discharged | ||
| 3:00pm | Patients were invited and consented to participate in the study |
At least 4 weeks before admission, medication affected plasma aldosterone or renin levels was replaced by other antihypertension drugs, e.g., verapamil, prazosin, moxonidine, and/or hydralazine. Patients were admitted to hospital to ensure the dietary (hospital normal diet) and posture requirements were met and to facilitate measurement of plasma K+ levels and other parameters. Oral KCl supplementation: if participants’ plasma K+ level at 7:00am on day 0 was <4 mmol/L, participants were given sufficient slow-release KCl (Span-K) up to four times per day (Q6h) to achieve as close to 4 mmol/L as possible by the next morning at 7:00am. ARR, aldosterone-to-renin ratio; SSST, seated saline suppression testing; uEV, urinary extracellular vesicles; KCl, potassium chloride, given as slow-released KCl (Span-K).