More than a fifth of patients who were transferred to attend inpatient post-COVID-19 rehabilitation experienced hallucinations, according study findings published in Archives of Rehabilitation of Research and Clinical Translation.
Hallucinations involve false sensory input as auditory, visual, olfactory, gustatory, tactile, and/or somatic sensations. These sensations are closely linked with schizophrenia and have been well-documented in neurodegenerative diseases, eye diseases, drug abuse, and as side effects from certain medications, and have been increasingly reported in COVID-19.
Researchers conducted the study at the Rancho Los Amigos National Rehabilitation Center in the United States in 2021 to evaluate the rate and trends of hallucinations in patients recovering from COVID-19. Electronic medical records of patients (N=37) transferred to their acute rehabilitation unit for post-COVID-19 care were evaluated for cognitive status and evidence of hallucinations.
The patients were mean age, 56.2 (range, 27-76) years, 56.8% were men, 91.9% were Hispanic, they had been hospitalized for 63.8 (range, 6-167) days, 48.7% had a critical case of COVID-19, and 16.2% a severe case.
A total of 8 patients had documented hallucinations. The patients who experienced hallucination were hospitalized for longer (mean, 116.4 vs 49.3 days; P <.0001), more had critical COVID-19 (100.0% vs 34.5%; P =.007), and required longer rehabilitation (mean, 30.0 vs 16.6 days; P =.032) compared with patients who did not have hallucinations, respectively.
Among the hallucination cohort, no patient had pre-existing mental health problems. In addition to the hallucinations, all patients exhibited cognitive impairment, but most had improved cognitive scores at rehabilitation discharge.
Hallucination symptoms included:
- Visual sensations (n=7)
- Delirium (n=5)
- Tactile or somatosensory sensations (n=5)
- Auditory sensations (n=5)
- Delusion (n=2)
The 3 main themes of hallucinations were comfort seeking, fearfulness, and visualizing deceased family members. Five patients thought the hallucinations were fear provoking or threatening.
A total of 2 patients had persistent hallucinations during their stay at the rehabilitation center, 1 of whom experienced 3 months of hallucinations and the other continued to experience hallucinations at discharge, which was 166 days after their COVID-19 diagnosis.
This study was limited by its small sample size and single-center, retrospective design.
The researchers concluded that hallucinations were not uncommon following critical COVID-19, and that the most common hallucination symptoms were consistent with peduncular hallucinosis. “The hallucinations can be a part of delirium; however, they can be manifestations in the CNS of SARS-CoV-2 infection,” they acknowledged. Additional investigation of trends in hallucinations in COVID-19 is needed to better understand the etiology these hallucinations.
Tobita M, Fanchiang S-P, Saldivar A, Taylor S, Jordan B. Complex Hallucinations in Hospitalized Rehabilitation Patients With COVID-19. Arch Rehabil Res Clin Transl. Published online October 17, 2022. doi:10.1016/j.arrct.2022.100234