Haemodynamic effects of fludrocortisone and midodrine in patients with symptoms due to hypotension.

Aim: The study aimed to assess the haemodynamic effects of fludrocortisone and midodrine, alone or combined, in patients with recurrent syncope and/or symptoms due to hypotension and ≥ 1 daytime systolic blood pressure (SBP) drop < 90 mmHg or ≥ 2 daytime SBP drops < 100 mmHg recorded by 24-h ambulatory blood pressure monitoring (ABPM1).

Method: A total of 53 patients (mean age, 40.9 ± 18.5 years, 37 female) were treated with fludrocortisone (0.05-0.2 mg per day) and/or midodrine (2.5-10 mg two or three times per day). A second ABPM (ABPM2) was performed within 6 months and the results of ABPM1 AND ABPM2 were compared to assess the effects of BP-rising drugs.

Results: In 32 patients assigned to fludrocortisone, 24-h SBP increased from 107.1 ± 9.9 mmHg to 116.3 ± 14.9 (p = 0.0001), the number of daily SBP drops < 90 mmHg decreased by 73% (p = 0.0001) and that of drops < 100 mmHg decreased by 41% (p = 0.0005). In 14 patients assigned to midodrine, 24-h SBP increased from 112.7 ± 7.4 mmHg to 115.0 ± 9.1 (p = 0.12), the number of daily SBP drops < 90 mmHg decreased by 52% (p = 0.04) and that of drops < 100 mmHg decreased by 34% (p = 0.007). In the seven patients taking both fludrocortisone and midodrine, 24-h SBP increased from 110.1 ± 11.5 mmHg to 114.0 ± 12.4 (p = 0.002), the number of daily SBP drops < 90 mmHg decreased by 69% (p = 0.22) and that of drops < 100 mmHg decreased by 44% (p = 0.04).

Conclusions: Both fludrocortisone and midodrine effectively increased 24-h SBP and reduced SBP drops on ABPM but fludrocortisone seemed to be more effective than midodrine. Further randomised studies are needed to confirm these observations.