Unraveling the challenges of diagnosing dementia with Lewy bodies in a patient with alcohol and benzodiazepine misuse: A case study-based review

Dementia with Lewy bodies (DLBs) is the second most common cause of neurodegenerative dementia in the United States, after Alzheimer’s disease, and is often misdiagnosed. A history of substance use disorder (SUD) complicates the diagnosis process, and side effects of substance misuse can mirror or mask signs of degenerative dementia. The fluctuating cognition and mobility which would normally point toward DLB are erroneously seen as signs of SUD or polypharmacy. However, a history of SUD should not preclude the diagnosis of DLB or other forms of proteinopathy, as substance misuse can contribute to the development of neurodegenerative dementias. Both alcohol and benzodiazepines have a sedative effect as ligands to gamma-aminobutyric acid (GABA) receptors. Long-term use, misuse, and withdrawals can upset the delicate GABAergic/glutamatergic balance, resulting in adverse neuroimmune and neuroinflammatory responses which contribute to the pathologies seen in degenerative dementias, such as DLB. In this paper, we review the challenges, including limitations of standardized instruments for dementia and the harms of delayed diagnosis, in DLB diagnosis, in combination with our experiences drawn from studying a polypharmacy-practicing 68-year-old man with a 40-year history of benzodiazepine and alcohol use. Understanding the underlying mechanisms of SUD serves to destigmatize the condition to expedite treatment and further our knowledge of the relationship between neuroinflammation and dementia.