ACR CONVERGENCE 2020—With the inevitable decline in organ function that comes with age, and the likelihood that older patients (i.e., generally defined as older than 60 or 70, depending on the study) are on more than one medication due to multiple comorbidities, therapeutic drug treatment for older patients requires persistent vigilance and know-how, two experts said during a session at the meeting in November.
Ananta Subedi, MD, an attending rheumatology physician with WakeMed Physician Practices, Raleigh, N.C., said a decline in kidney function and liver function, in particular, puts older patients at higher risk of adverse drug events, but the use of most medications remains reasonable in these patients, as long as they’re used correctly.
“[Because] the elderly population is more vulnerable to adverse drug events, there is a fine balance between adequate treatment and the risk of adverse events with the use of medications,” he said. “The available evidence supports the use of most disease-modifying, anti-rheumatic drugs (DMARDs), which could help minimize the overuse of non-steroidal drugs and corticosteroids.” Non-steroidals and corticosteroids bring added risk of osteoporosis and cardiovascular problems, he said.
The normal dosing of jakinibs typically must be cut in half for elderly patients.
Suraj Rajasimhan, PharmD, a clinical pharmacy specialist at the National Institutes of Health, said that in spite of the need for data on what works best in these often-complicated cases, relatively little information exists in the literature. Elderly patients, he said, are often excluded from trials, “and these are the patients who are having multiple comorbid conditions and are on multiple medications and are also prone to polypharmacy.”
Dr. Subedi urged clinicians not to fall victim to stereotyping elderly patients as non-adherent to their drug regimens due to cognition issues. It is true, he said, that rheumatoid arthritis patients are at a higher risk of cognitive impairment, but studies have found busy, middle-aged adults are most likely to be non-compliant, not the elderly.1 “We need to stop blaming just the age for the medication non-compliance,” he said.
The doctors went on to offer these observations:
The Advice
- Drug-dosing should be based on that of patients with known renal insufficiency because serum creatinine levels can remain within normal limits even with a decrease in glomerular filtration rate (GFR), Dr. Subedi said.
- In giant cell arteritis and polymyalgia rheumatica, stopping prednisone has been associated with a reduction in mortality risk, showing “the importance of appropriate use of corticosteroids in giant cell arteritis,” Dr. Subedi said.2
- Elderly onset rheumatoid arthritis (RA) is less frequently treated with biologics and combination DMARDs than in those with younger onset RA, while non-steroidal anti-inflammatory drugs and corticosteroids are overused, Dr. Subedi said.
- Regarding methotrexate, Dr. Rajasimhan said, “renal function is important to monitor when methotrexate is given to an elderly patient, especially when they are on concomitant medications that can affect their GFR. They should be started on a low dose and monitored more frequently.”
- Sulfasalazine can bring on dose-related gastrointestinal adverse effects, so dosing should be increased only gradually. Patients who are slow to detoxify drug metabolites in the liver will have a higher serum concentration of sulfasalazine. Patients with a deficiency in G6PD, an enzyme important for red blood cell function, are at risk of hemolytic anemia, so this must be monitored.
- The normal dosing of Janus kinase inhibitors (jakinibs) typically must be cut in half for elderly patients, Dr. Rajasimhan said.
- The most severe adverse effects of jakinibs tend to be infections, and that risk can be mitigated with vaccines, particularly the herpes zoster vaccine. Glucocorticoids boost the infection risk, Dr. Rajasimhan said.
- The infection risk associated with biologics tends to be highest early in the course of therapy, so patients should be monitored closely at the start, Dr. Rajasimhan said.
- Special prescribing procedures for elderly patients can prove beneficial, Dr. Rajasimhan said.
Final Thoughts
“The best interaction may involve an interprofessional approach that can include a clinical pharmacist,” Dr. Rajasimhan said. “Elderly patients [can] have complex medication regimens [and] multiple comorbid conditions.
It’s important for clinicians to dose these medications appropriately and avoid drug-drug interactions and
adverse effects.”