Possible causes of difficult-to-treat hypertension
| Suboptimal antihypertensive therapy |
| Nonadherence |
| Lifestyle choices (eg, high-sodium diet, smoking) |
| Dietary indiscretion |
| Over-the-counter medications and supplements |
| Older age |
| Intravascular and extracellular volume expansion |
| Primary hyperaldosteronism |
| Renal artery stenosis |
| Renal parenchymal disease |
| Obstructive sleep apnea |
| Coarctation of the aorta |
| Cushing disease |
| Hyperparathyroidism |
| Pheochromocytoma |