Diagnosis of Rapidly Progressive Dementia in a Referral Center in Argentina

The Etiology of Rapidly Progressive Dementia: A 3-Year Retrospective Study in a Tertiary Hospital in China

Background

Rapidly progressive dementia (RPD), characterized by a rapid cognitive decline leading to dementia, comprises a diverse range of disorders. Despite advancements in diagnosis and treatment, research on RPD primarily focuses on Western populations.

Objective

This study aims to explore the etiology and demographics of RPD in Chinese patients.

Methods

We retrospectively analyzed 323 RPD inpatients at Huashan Hospital from May 2019 to March 2023. Data on sociodemographic factors, epidemiology, clinical presentation, and etiology were collected and analyzed.

Results

The median onset age of RPD patients was 60.7 years. Two-thirds received a diagnosis within 6 months of symptom onset. Memory impairment was the most common initial symptom, followed by behavioral changes. Neurodegenerative diseases accounted for 47.4% of cases, with central nervous system inflammatory diseases at 30.96%. Autoimmune encephalitis was the leading cause (16.7%), followed by Alzheimer's disease (16.1%), neurosyphilis (11.8%), and Creutzfeldt-Jakob disease (9.0%). Alzheimer's disease, Creutzfeldt-Jakob disease, and frontotemporal dementia were the primary neurodegenerative causes, while autoimmune encephalitis, neurosyphilis, and vascular cognitive impairment were the main non-neurodegenerative causes.

Conclusions

The etiology of RPD in Chinese patients is complex, with neurodegenerative and non-neurodegenerative diseases equally prevalent. Recognizing treatable conditions like autoimmune encephalitis and neurosyphilis requires careful consideration and differentiation.

Prevalence and outcomes of rapidly progressive dementia: a retrospective cohort study in a neurologic unit in China

BACKGROUND

Rapidly progressive dementia (RPD) is a syndrome originating from various diseases. Recent advances have allowed a better understanding of its categories and spectrum; however, it remains challenging to make an accurate differential diagnosis and prognosis prediction.

METHODS

This study was a retrospective evaluation of all participants admitted to the neurology department of a single center in China from January 2015 to December 2019. The screened patients met the RPD criteria and their characteristics were collected to explore a diagnostic pattern of RPD. In addition, outcomes of RPD were evaluated with the Glasgow Outcome Scale (GOS), activities of daily living scale (ADL), and simplified Mini-Mental State Examination (MMSE), and different prognostic analysis methods were performed to determine the prognostic factors of RPD.

RESULTS

A total of 149 RPD patients among 15,731 inpatients were identified with an average MMSE value of 13.0 ± 4.6 at baseline. Etiological epidemiology revealed infectious, neurodegenerative and toxic/metabolic diseases as the three largest groups, accounting for 26.2%, 20.8% and 16.8% of all cases, respectively. In particular, prevalence rates of Creutzfeldt-Jakob disease (13.4%), Alzheimer's disease (11.4%), carbon monoxide poisoning (8.1%), neurosyphilis (5.4%) and dementia with Lewy bodies (5.4%) were highest in this series. A recommended diagnostic framework for RPD etiology was thus established. Follow-up evaluations showed a negative correlation between age and GOS scores (r=-0.421, P < 0.001), as well as age and simplified MMSE scores (r_s =- 0.393, P < 0.001), and a positive correlation between age and ADL scores (r_s =0.503, P < 0.001), and significantly different GOS, ADL and simplified MMSE scores across various etiologies (P = 0.003; F = 9.463, P < 0.001; F = 6.117, P < 0.001).

CONCLUSION

Infectious, neurodegenerative and toxic-metabolic entities were the most common RPD categories, and establishing a practical approach to RPD etiology would allow better disease management.

Rapidly progressive dementias - aetiologies, diagnosis and management

Rapidly progressive dementias (RPDs) are a group of heterogeneous disorders that include immune-mediated, infectious and metabolic encephalopathies, as well as prion diseases and atypically rapid presentations of more common neurodegenerative diseases. Some of these conditions are treatable, and some must be diagnosed promptly because of their potential infectivity. Prion disease is considered to be the prototypical RPD, but over the past two decades, epidemiological reports and the identification of various encephalitis-mediating antibodies have led to a growing recognition of other encephalopathies as potential causes of rapid cognitive decline. Knowledge of RPD aetiologies, syndromes and diagnostic work-up protocols will help clinicians to establish an early, accurate diagnosis, thereby reducing morbidity and mortality, especially in immune-mediated and other potentially reversible dementias. In this Review, we define the syndrome of RPD and shed light on its different aetiologies and on secondary factors that might contribute to rapid cognitive decline. We describe an extended diagnostic procedure in the context of important differential diagnoses, discuss the utility of biomarkers and summarize potential treatment options. In addition, we discuss treatment options such as high-dose steroid therapy in the context of therapy and diagnosis in clinically ambiguous cases.

The term ‘rapidly progressive dementia’ (RPD) describes a cognitive disorder with fast progression, leading to dementia within a relatively short time. This Review discusses the wide range of RPD aetiologies, as well as the diagnostic approach and treatment options.

Definitions of rapidly progressive dementia (RPD) vary according to the aetiological background and relate to the speed of cognitive decline, time from first symptom to dementia syndrome and/or overall survival.

RPD can occur in rapidly progressive neurodegenerative diseases, such as prion diseases, or in primarily slowly progressive diseases as a consequence of intrinsic factors or concomitant pathologies.

Besides neurodegenerative diseases, inflammatory (immune-mediated and infectious), vascular, metabolic and neoplastic CNS diseases are important and frequent causes of RPD.

To identify treatable causes of RPD, the technical diagnostic work-up must include MRI and analyses of blood and cerebrospinal fluid, and further diagnostics might be indicated in unclear cases.

Therapeutic options for many non-neurodegenerative causes of RPD are already available; disease-modifying therapies for neurodegenerative RPDs are an important focus of current research and could become a treatment option in the near future.

Evolving Causes of Rapidly Progressive Dementia: A 5-Year Comparative Study

BACKGROUND

Rapidly progressive dementia (RPD) is a clinical syndrome developing in <1 to 2 years. Recent progress in RPD evaluation is significant, so RPD's prevalence may change over time. The aim of our new case series was to estimate the relative frequency of RPDs' causative entities, considering the recent advances in RPDs' diagnosis, and compare the results with those of our previous report.

PATIENTS AND METHODS

We retrospectively reviewed the medical records of 47 patients who were referred to Attikon University Hospital during a 5-year period for a suspected RPD.

RESULTS

Neurodegenerative diseases were the most frequent causes (38%), followed by prion disease (19%) and autoimmune encephalopathy (AE, 17%). AE cases were by far more common than in our previous report, while other than AE secondary causes were significantly decreased. Mean time to dementia was 9 months in neurodegenerative diseases and 5 months in non-neurodegenerative. Main clinical findings across all patients were memory impairment (66%) and behavioral-emotional disturbances (48%).

CONCLUSIONS

Neurodegenerative diseases are common causes of RPD and have a slower evolution than non-neurodegenerative. Diagnostic novelties enabled the recognition of AE, whereas more common secondary causes are probably now diagnosed in primary settings since the recognition of RPD as distinct clinical entity is continually increasing.