To the Editor: A clear distinction between schizophrenia and some clusters of dementia is sometimes difficult to establish in clinical practice.

A 38-year-old man with a history of alcohol dependence (alcohol consumption started at the age of 6 years) was admitted to our unit for generalized tremor; sweating; agitation; auditory, visual, and kinesthetic hallucinations; thought-broadcasting; and persecutory delusion. He was medicated with diazepam, 20 mg, and thiamine, 200 mg. Agitation and the vegetative symptoms gradually subsided within 48 hours. Lab work showed no significant changes, and EEG and ECG were normal. A brain MRI showed generalized cortical atrophy. Seven days after the admission, we prescribed olanzapine 10 mg because the psychotic symptoms had persisted. There was a gradual improvement, and, 26 days after admission, the patient was discharged home asymptomatic. Two months later he was admitted to a medical unit for a grand mal seizure after a 48-hour period of abstinence. After medical stabilization, psychiatric evaluation elicited the same previous psychotic symptoms. Olanzapine, 10 mg, was again prescribed, with symptomatic improvement. A neuropsychological study, requested during follow-up because of his cognitive impairment, revealed a severe frontotemporal cognitive defect.

During the year before the admission, the patient presented with auditory and kinesthetic hallucinations, thought-broadcasting, and persecutory delusions. Also, he had continued drinking large amounts of alcohol daily during this period.

Alcohol has not been identified as a possible etiological factor for schizophrenia. Also, the high comorbidity between alcohol abuse and schizophrenia remains obscure.¹ Alcoholic dementia is controversial. Long-term alcohol abuse appears to elicit its onset later in life through a mechanism of continuous brain insult.^2,3

Beginning his alcohol consumption at the age of 6, cognitive deterioration, and generalized cortical atrophy shown in the brain MRI suggest an alcoholic dementia.⁴ However, maintenance of typical positive schizophrenia symptoms beyond delirium tremens as with alcohol abstinence fulfills DSM-IV diagnostic criteria for schizophrenia. Also, the same neuropsychological deficits encountered in our patient are described in early-onset frontotemporal dementia presenting as schizophrenia-like psychosis in young people.⁵

The difficulty in clearly distinguishing schizophrenia from some dementias may be because, as Kraepelin stated in the 19th century, schizophrenia is itself a form of early dementia. His concept of dementia praecox^6,7 is supported nowadays by the knowledge acquired from several neuropsychological and neuroimaging tests that a progressive cognitive deterioration occurs in schizophrenic patients. Our case also supports this phenomenological concept of dementia praecox, independently of the associated etiological mechanisms.