In patients who have worsening dysphagia associated with pneumonia, insertion of an enteral feeding tube, such as a percutaneous endoscopic gastrostomy (PEG) tube, can provide adequate nutrition and may reduce the risk of future episodes of pneumonia (although this practice is controversial).
In one study, there was a 45% reduction in the incidence of pneumonia in the year following feeding-tube insertion.9 Other investigators have not found that gastrostomy tubes prevent pneumonia, however.10 Instead, the presence or absence of gastroesophageal reflux and whether or not the patient has a prior history of aspiration pneumonia seem to be more important factors in determining if episodes of pneumonia will occur after feeding-tube placement.
The prevalence of gastroesophageal reflux (GER) in 435 institutionalized patients with IQ <50 ID was 48.2%.11 Almost 70% of patients with GER had reflux esophagitis, while 14% had Barrett’s esophagus, and 3.9% had peptic strictures. Bui and colleagues studied 105 ID patients with feeding gastrostomy, 45 of whom had dysphagia but no history of aspiration pneumonia and 60 who had recurrent aspiration, either alone or with dysphagia.12 Only two of 45 (4.4%) patients with dysphagia alone developed aspiration pneumonia, while 15 of 60 (25.0%) with a prior history of aspiration pneumonia had a future event.12
Continued aspiration pneumonia may be due to oral secretions and gastric contents entering the respiratory tract. Preoperative GER has been associated with postoperative aspiration pneumonia.10 Elevating the head of the bed, avoiding bolus feeding, treating constipation, discontinuing feeding promptly in cases of respiratory distress or increased gastric residual volume, and treating gastroesophageal reflux pharmacologically may decrease further pneumonia events in these patients.9
Another common issue hospitalists must be attuned to in adult patients with ID is epilepsy. Prevalent in as many as 40% of adult patients with mental retardation and cerebral palsy, uncontrolled epilepsy has been associated with increased mortality.13,14 Clinical guidelines for the management of epilepsy in this population have been published.15 Recommended first-line treatments of generalized seizures include sodium valproate and lamotrigine. If these medications are unsuccessful, or if side effects prohibit continued usage, then topiramate and carbamazepine are suggested. Do not use carbamazepine in myoclonic or absence seizures. Lennox-Gastaut syndrome can be treated with lamotrigine, while topiramate and felbamate can be used as add-on therapy to reduce atonic seizures.
For treatment of partial seizures, valproate, carbamazepine, and lamotrigine are recommended first-line treatments. Levetiracetam can be used as add-on therapy. The guidelines suggest that studies of add-on therapy failed to differentiate among lamotrigine, gabapentin, topiramate and tiagabine.
Adjust the initial anti-epileptic drug (AED) to the maximum tolerated dose before slowly introducing a second AED without tapering the first. If the patient responds to the second drug, consider a gradual tapering of the first drug. It is not uncommon for multiple AEDs to be used in patients with ID. In patients referred to a specialized epilepsy clinic, over 80% were on two or more AEDs; 43% became seizure-free for a year or more, while another 40% of patients had a 50% or greater reduction in seizure frequency.16
AEDs that induce the cytochrome P-450 system—particularly phenytoin—phenobarbital, and carbamazepine, have been associated with low bone mineral density (BMD) in patients with ID.17 Additional risk factors for low BMD, such as hypogonadism, low body mass, decreased mobility, and vitamin D deficiency may contribute to the increased incidence of non-traumatic fractures found in institutionalized adults with ID.18,19 In one study, the annual incidence of non-traumatic fracture was 7.3% among 391 institutionalized adults.18