Ropinirole-Associated Orthostatic Hypotension as Cause of a Prescribing Cascade in an Elderly Man

Abstract

Ropinirole is an overall well-tolerated antiparkinsonian medication that is also used to treat restless leg syndrome (RLS). The incidence of side effects is low, with orthostatic hypotension (OH) only anecdotally reported. Additionally, it is known that the elderly population is very susceptible to adverse drug effects and the prevalence of prescribing cascades that these can trigger is unknown. A 71-year-old male with history of atrial fibrillation, well-controlled diabetes on oral agents, hyperlipidemia, hypertension, ischemic heart failure status post (s/p) implantable cardioverter-defibrillator (ICD) placement with improved ejection fraction (EF), transient ischemic attack (TIA), rheumatoid arthritis, RLS, aortic stenosis s/p mechanical aortic valve replacement on anticoagulation, deep venous thrombosis (DVT), and right knee replacement, presented to the ED with generalized weakness, with difficulty standing from seated position, followed by a fall without head trauma. Over the eight months prior to this presentation, the patient had had similar symptoms that resulted in four falls, two hospital admissions, and new prescriptions of midodrine and compression stockings. On admission, vital signs were remarkable for positive orthostatics with blood pressure (BP) 110/74 mmHg, heart rate (HR) of 86 bpm in supine position and BP 87/51 mmHg, HR of 70 bpm while in standing position. Physical exam was unremarkable except for a known ejection murmur and dry oral mucous membranes. Labs included a creatinine 3.6 mg/dl, blood urea nitrogen (BUN) 66 mg/dl, international normalized ration (INR) of 4.1, B-natriuretic peptide (BNP) of 313 pg/mL, troponin <0.03 ng/mL. A kidney ultrasound was normal, and a transthoracic echocardiogram showed left ventricle ejection fraction (LVEF) of 55-65%, improved compared to a prior study. Furosemide, carvedilol and canagliflozin were discontinued and IV fluids were administered. In the subsequent days, his creatinine improved, and so did the patient's volume status, but he continued to be orthostatic despite midodrine and stockings. On further interview, the patient disclosed starting ropinirole 0.25 mg three times daily approximately 10 months prior to this admission, due to asymptomatic RLS that was reported in a sleep study. Decision was made to discontinue this medication, which resulted in improvement of symptoms. We were able to discontinue IV fluids, midodrine and stockings, and reintroduce carvedilol, furosemide and canagliflozin in a stepwise manner. In a follow-up visit one month after discharge, the patient was symptom-free. This case illustrates two major points. First, this prescribing cascade potentially induced by ropinirole, as well as the increase in health care costs associated to iatrogenic admissions, is major preventable problem faced mostly by the geriatric population. Second, although OH associated with ropinirole has only been reported in patients treated for Parkinson's disease, this side effect should be considered when prescribing ropinirole for other indications, with cautious assessment of risks and benefits. Further studies need to be conducted to establish the frequency of OH related to ropinirole.

Keywords: hypotension; medication safety; older adult; prescribing cascade; ropinirole; side effect.

Figure 1. (A) Initial patient presentation and differential diagnosis. (B) Hospital course and follow-up.

Figure 2. Summary of case

Figure 3. Prescribing cascade overview