Stress load and neurodegeneration after gastrostomy tube placement in amyotrophic lateral sclerosis patients

Abstract

Dysphagia and progressive swallowing problems due to motoneuron death is one of amyotrophic lateral sclerosis (ALS) symptoms. Malnutrition and body weight loss result in immunological disturbances, fatigability and increase risk of secondary complications in ALS patients, percutaneous endoscopic gastrostomy tube (PEG) placement representing a well-recognized method for malnutrition correction and potentially increasing life expectancy. However, despite nutritional correction, occasional rapid neurological deterioration may develop after PEG placement. We have hypothesized that this decline can be a result of exteroceptive stress during PEG placement and promote neurodegeneration in ALS patients. Intravenous sedation may decrease stress during invasive procedures and it is safe during PEG placement in ALS patients. The aim of the study was comparing different PEG placement protocols of anesthesia (local anesthesia or local anesthesia plus intravenous sedation) in ALS from perspectives of stress load and neurological deterioration profile. During 1.5 years 94 ALS patients were admitted; gastrostomy was performed in 79 patients. After screening according to inclusion and exclusion criteria, 30 patients were included in the prospective consecutive study. All patients were divided in two groups, with local anesthesia and with combination of local anesthesia and intravenous sedation. Routine biochemical indices, neurodegeneration and stress markers were measured. The age of ALS patients was 61 ± 10 years; 20 patients were included at stage 4A and 10 at stage 4B (King's College staging). PEG was placed at average14 months after the diagnosis and 2.2 years after first symptoms. Mean ALS Functional Rating Scale-Revised was 27.8, mean forced vital capacity of lung 46.3% (19-91%). After one year of observation only 8 patients survived. Mean life duration after PEG was 5 months (5 days-20 months). Comparison of two PEG placement protocols did not reveal differences in survival time, stress load and inflammation level. Higher saliva cortisol levels, serum cortisol, glucose, C-reactive protein and interleukin-6 were detected after PEG placement, confirming considerable stress response. PEG is a stressful factor for ALS patients, PEG placement representing a natural model of exteroceptive stress. Stress response was detected as increased cortisol, C-reactive protein, interleukin-6, and glucose levels. Intravenous sedation did not increase the risk of PEG placement procedure, however, sedation protocol did not affect stress load.

Keywords: ALS; Gastrostomy; Neurodegeneration; Neuroinflammation; Sedation; Stress.