geropsych pearls

The Quick and Dirty on Restless Leg Syndrome

RLS is common in older adults, and is often associated with paresthesias or motor restlessness. Sx tend to be worse in the evening, and less severe in the morning. RLS is associated with poor QOL, so treat it. 

Primary RLS is thought to be related to genetic abnormalities in the central & subcortical dopamine pathways + impaired iron homeostasis. Check a ferritin level, IBC,  and all that good stuff.

That said, most RLS is secondary to something else, and usually multifactorial. Main culprits are B12, folate, or mag deficiency, peripheral neuropathy, uremia. The usual med suspects are SSRIs. In fact, almost all SSRIs can worsen RLS in elders, so pull back the dose. Other offenders include antidopaminergics, neuroleptics, diphenhydramine, alcohol, caffeine, lithium, b-blockers.

  • Treat by removing the offending agent or replacing the deficiency (eg B12). 
  • There is some benefit to dopaminergics, such as pramipexole, ropinirole, bromocriptine +/- levodopa.
  • Gapapentin works well in elders, but keep in mind that they are gonna gain weight.
  • Horizant is an extended-release form of gabapentin that is FDA approved to treat restless legs syndrome, but it is really expensive. I've never used it, so let me know your experience. 

Here's the caveat! (You KNOW there always is one, right?)
Would make sure that RLS is not actually periodic limb movement disorder (PLMD), which is characterized by stereotypical repetitive, rhythmic, nocturnal myoclonus, that can be unilateral or bilateral. Partial arousal leads to sleep fragmentation and hypersomnolence. Secondary PLMD is caused by diabetes mellitus, spinal cord tumor, sleep apnea, narcolepsy, uremia, anemia. There is also an association between ADHD and PLMD. Medication culprits include dopaminergic meds, TCAs, benzo withdrawal, barbiturate withdrawal. Polysomnography is helpful. 

So how do you know which it is? 

Easy peasy! Who's the one complaining? 

  • If the pt is c/o the creepy crawlies, then it's probably RLS. Remember, most RLS occurs during wakefulness. 
  • If the bed partner is complaining that the pt's legs jerk all night, and the pt is blissfully unaware, then it is probably PLMD.
  • Or, it could be both. Here's a fun factoid to impress your sleepy friends!  80% of elders with RLS also have PLMD, but not the reverse.

The L/D:

1. If the pt is c/o creepy crawlies, think RLS. Check B12, ferritin, and cut back that whopping SSRI that you started a few months ago.

2.  If the pt's partner is complaining that the pt's legs are jerking all night, think PLMD and refer to sleep specialist.