Use of high flow nasal cannula oxygen therapy for patients infected with SARS-CoV-2 outside intensive care setting.

Background: In early 2022, there was a sudden surge of patients infected by the Omicron variant of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in Hong Kong (HK), resulting in 9,163 deaths as of 29 May 2022. Many of the local population had not been vaccinated before this wave. The number of patients who developed coronavirus disease 2019 (COVID-19) related respiratory failure outnumbered the capacity of intensive care unit (ICU) beds. Some of these patients had to be supported with high flow nasal cannula (HFNC) therapy outside ICU setting. HK was in crisis situation. The primary objective of this study is to assess the 28-day mortality of this group of patients. The secondary objective is to explore any predictors of non-survivors to help clinical decision-making in future crisis. Methods: This is a retrospective observational study of patients suffering from COVID-19 related respiratory failure who received HFNC therapy in general medical wards of two hospitals during the period of 17 Mar to 30 Apr 2022. Survival and risk factors were reviewed. Results: Forty-nine patients were recruited. Twenty-six patients (53%) survived at 28-day after initiation of HFNC support. Three clinical parameters were found to be significantly associated with mortality at 28-day: (I) SpO2/FiO2 (SF) ratio <160 at 48 hours; (II) SF ratio <191 at 72 hours; (III) serial SF ratio at 48 or 72 hours showing no improvement over that at the time of initiation of HFNC therapy. Conclusions: Use of HFNC outside ICU setting showed benefit to patients suffering from COVID-19 related acute hypoxemic respiratory failure (AHRF). Serial SF ratio monitoring at 48 and 72 hours after therapy initiation might serve as predictors of outcome and thus guide clinical decision-making for medical resource allocation in outbreak situation.

Effect of CYP2D6 and CYP3A4 Genotypes on the Efficacy of Cholinesterase Inhibitors in Southern Chinese Patients With Alzheimer's Disease.

Alzheimer's disease (AD) is the most prevalent form of dementia, and age is strongly associated with the incidence of AD. This study aimed to investigate the association between the genotypes of CYP2D6, CYP3A4, and CYP2C9 genes to the clinical efficacy and tolerability of cholinesterase inhibitors (ChEIs) in Chinese patients with AD. One hundred seventy-nine patients with AD with newly prescribed with ChEIs were recruited. The clinical response and tolerability were evaluated at baseline, 3rd-, 6th-, and 12th-month follow-ups and were compared according to their genotypes of CYP2D6, CYP3A4, and CYP2C9. Among patients prescribed with donepezil/galantamine, CYP2D6*10 carriers showed significantly less side effects (P = .009). CYP2D6*10 carriers responded better to ChEIs and resulted in better improvement in Alzheimer's Disease Assessment Scale-Cognitive subscale (P = .027) and Mini-Mental State Examination (P = .012). Further study is required to replicate the finding, and it might be useful for clinicians to decide the medication based on the patients' CYP genotypes.

Characteristics and diagnostic profile of patients seeking dementia care in a memory clinic in Hong Kong.

BACKGROUND: Seeking medical advice for dementia involves an understanding of norms, values and attitudes towards care-giving and inter-dependency, which are culturally bounded. We hypothesize that local culture and socioeconomic structure affect our Chinese patients who present with forgetfulness to our memory clinic. METHODS: A retrospective case notes review was undertaken on 454 consecutive patients referred to the memory clinic at Princess Margaret Hospital, Hong Kong. RESULTS: 385 patients were diagnosed with dementia and 27 had mild cognitive impairment. Reversible dementia was identified in 24 patients and normal cognition in 18. In patients with dementia, 55.8% had Alzheimer's disease, 26.2% had vascular dementia, 6.0% had other irreversible dementia, 5.2% had dementia with Lewy bodies, 4.9% had undetermined dementia and 1.8% had frontotemporal dementia. The median duration from symptom onset to medical consultation was two years; 66.5% had advanced disease with initial Mini-mental State Examination scores < or = 17. On their first visit, 85% of patients were living in the community; after two years this proportion had fallen to 63%. CONCLUSIONS: Dementia patients in Hong Kong apparently enjoy a long subclinical period and only seek medical attention at late stages. Local Chinese culture and socioeconomic backgrounds could be the main reasons that underlie these observations.

Coexisting cerebral infarction in Alzheimer's disease is associated with fast dementia progression: applying the National Institute for Neurological Disorders and Stroke/Association Internationale pour la Recherche et l'Enseignement en Neurosciences Neuroimaging Criteria in Alzheimer's Disease with Concomitant Cerebral Infarction.

OBJECTIVES: To determine whether patients with Alzheimer's disease (AD) and coexisting cerebral infarction (CI) that satisfy the National Institute for Neurological Disorders and Stroke/Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN) neuroimaging criteria for vascular dementia (VaD) progress faster than those who do not satisfy the neuroimaging criteria. DESIGN: Retrospective cohort study. SETTING: Multidisciplinary memory clinic in a tertiary hospital. PARTICIPANTS: One hundred thirty consecutive patients with AD, with or without CI, followed up regularly for more than 1 year. MEASUREMENTS: The patients were classified according to the distribution and severity of CI as defined according to the NINDS-AIREN neuroimaging criteria into those with AD and no CI (AD-N), those with AD and CI not fulfilling neuroimaging criteria (AD-I), and those with AD and CI fulfilling neuroimaging criteria (AD-V), and their differences in dementia progression were tested. The loss of independence, indicated by institution admission or a clinical dementia rating (CDR) score of 3, was defined as the endpoint for a poor outcome. RESULTS: The mean age was 75.8, and 68.5% were women. The initial Mini-Mental State Examination (MMSE) score was 15.3+/-0.4, and the average duration of follow up was 30.4 months. Fifty-four patients had reached study endpoint at the time of analysis. AD-V (hazard ratio (HR)=3.1, 95% confidence interval (CI)=1.2-8.2), use of psychotropic drugs (HR=2.7, 95% CI=1.1-6.4), and initial MMSE score (HR=0.9, 95% CI=0.8-1.0) were independent predictors of poor outcome in the Cox regression model. CONCLUSION: In AD, co-occurrence of CI with distribution and severity as defined in the NINDS-AIREN neuroimaging criteria for VaD is associated with faster dementia progression.