From the Guidelines
For treating orthostatic hypotension in very elderly patients, midodrine is generally preferred over fludrocortisone. Midodrine (starting at 2.5-5 mg three times daily, with doses before getting up, at midday, and in the afternoon but not after 6 PM) tends to be better tolerated in the very old, as it works by directly constricting blood vessels to maintain blood pressure upon standing 1. Fludrocortisone (typically 0.1-0.2 mg daily) can be effective but carries higher risks in the elderly, including fluid retention, electrolyte imbalances, heart failure exacerbation, and supine hypertension 1.
Some key points to consider when using midodrine include:
- Monitoring for supine hypertension by checking blood pressure while lying down
- Watching for potential side effects like urinary retention, piloerection (goosebumps), and scalp tingling
- Starting with a low dose and titrating as needed to minimize side effects
Before starting either medication, non-pharmacological approaches should be tried, including:
- Adequate hydration
- Salt intake (if not contraindicated)
- Compression stockings
- Slow positional changes
- Education on lifestyle modifications, such as gradual staged movements with postural change, mild isotonic exercise, and head-up bed position during sleep 1
The choice between these medications should ultimately be individualized based on the patient's comorbidities, other medications, and specific clinical situation, with consideration of the potential benefits and risks of each treatment option 1.
From the FDA Drug Label
Midodrine has been studied in 3 principal controlled trials, one of 3-weeks duration and 2 of 1 to 2 days duration. All studies were randomized, double-blind and parallel-design trials in patients with orthostatic hypotension of any etiology and supine-to-standing fall of systolic blood pressure of at least 15 mmHg accompanied by at least moderate dizziness/lightheadedness Midodrine should be used with caution in orthostatic hypotensive patients who are also diabetic, as well as those with a history of visual problems who are also taking fludrocortisone acetate, which is known to cause an increase in intraocular pressure and glaucoma. Midodrine has been used in patients concomitantly treated with salt-retaining steroid therapy (i.e., fludrocortisone acetate), with or without salt supplementation.
Midodrine vs Fludrocortisone for Orthostatic Hypotension in Very Old Patients
- There is no direct comparison between midodrine and fludrocortisone in the provided drug labels.
- Midodrine is indicated for the treatment of symptomatic orthostatic hypotension, and its use has been studied in patients with orthostatic hypotension of various etiologies.
- Fludrocortisone is mentioned as a concomitant medication that may interact with midodrine, but its use as a treatment for orthostatic hypotension is not directly addressed in the provided drug labels.
- No conclusion can be drawn about which medication is better for treating orthostatic hypotension in very old patients, as the FDA drug label does not provide a direct comparison between midodrine and fludrocortisone 2, 2, 2.
From the Research
Comparison of Fludrocortisone and Midodrine for Orthostatic Hypotension in Very Old Patients
- Both fludrocortisone and midodrine are used to treat orthostatic hypotension, but their effectiveness and safety in very old patients may vary.
- A study from 1996 3 found that fludrocortisone was poorly tolerated in the long term in older patients with hypotensive disorders, with 33% of patients discontinuing treatment due to adverse events such as hypertension, cardiac failure, and depression.
- In contrast, midodrine has been shown to be efficacious and safe in the treatment of neurogenic orthostatic hypotension, with improvements in standing systolic blood pressure and symptoms of lightheadedness 4, 5.
- A study from 2015 6 reported a case of an 84-year-old patient with primary orthostatic hypotension who showed gradual improvements in symptoms and blood pressure control after being treated with atomoxetine, but this does not directly compare fludrocortisone and midodrine.
- A systematic review from 2021 7 found very low-certainty evidence about the effects of fludrocortisone on blood pressure, orthostatic symptoms, or adverse events in people with orthostatic hypotension, highlighting the need for more research.
Efficacy and Safety Considerations
- Midodrine has been shown to increase standing systolic blood pressure and improve symptoms of lightheadedness in patients with neurogenic orthostatic hypotension 4, 5.
- Fludrocortisone may not be well tolerated in very old patients, with a higher risk of adverse events such as hypertension, cardiac failure, and depression 3.
- The choice between fludrocortisone and midodrine may depend on individual patient factors, such as the underlying cause of orthostatic hypotension, comorbidities, and tolerance to potential side effects.
Research Gaps and Future Directions
- There is a need for more research on the long-term effects of fludrocortisone and midodrine in very old patients with orthostatic hypotension.
- Standardized reporting of outcomes and measurements of blood pressure in orthostatic hypotension are necessary to improve the quality of evidence 7.