Clusterization of Behavioral and Psychological Symptoms of Dementia as Assessed by Neuropsychiatric Inventory: A Case Against the Use of Principal Component Analysis.

Background: The term Behavioral and Psychological Symptoms of Dementia (BPSD) covers a group of phenomenologically and medically distinct symptoms that rarely occur in isolation. Their therapy represents a major unmet medical need across dementias of different types, including Alzheimer's disease. Understanding of the symptom occurrence and their clusterization can inform clinical drug development and use of existing and future BPSD treatments. Objective: The primary aim of the present study was to investigate the ability of a commonly used principal component analysis to identify BPSD patterns as assessed by Neuropsychiatric Inventory (NPI). Methods: NPI scores from the Aging, Demographics, and Memory Study (ADAMS) were used to characterize reported occurrence of individual symptoms and their combinations. Based on this information, we have designed and conducted a simulation experiment to compare Principal Component analysis (PCA) and zero-inflated PCA (ZI PCA) by their ability to reveal true symptom associations. Results: Exploratory analysis of the ADAMS database revealed overlapping multivariate distributions of NPI symptom scores. Simulation experiments have indicated that PCA and ZI PCA cannot handle data with multiple overlapping patterns. Although the principal component analysis approach is commonly applied to NPI scores, it is at risk to reveal BPSD clusters that are a statistical phenomenon rather than symptom associations occurring in clinical practice. Conclusions: We recommend the thorough characterization of multivariate distributions before subjecting any dataset to Principal Component Analysis.

Incidence of the Diagnosis of Anxiety Disorders in the Russian Federation: Results of a Web-Based Survey of Psychiatrists.

INTRODUCTION: According to the official Russian source, in 2017 only 0.27% of the population of Russia was diagnosed with International Classification of Diseases, tenth revision (ICD-10) F4 category disorders (neurotic, stress-related and somatoform disorders), despite these disorders being among the most prevalent mental disorders worldwide. Here we report the results of a large-scale survey among Russian psychiatrists with the primary objective to assess the proportion of psychiatrists who use the diagnoses of interest (mixed anxiety and depression disorder [MADD], adjustment disorder [AdD], panic disorder [PD], agoraphobia, generalized anxiety disorder [GAD], social phobia, simple phobia, acute stress disorder and posttraumatic stress disorder) and compare results with those of a recent World Psychiatric Association (WPA) and World Health Organization (WHO) survey. We also compared the incidence of these diagnoses between state and non-state psychiatric services in Russia. METHODS: Mean proportions and distribution of proportions of participants who made diagnoses of interest at different rates were calculated and compared with the results of the recent WPA and WHO survey. Risk ratios (RR) of the incidence of these diagnoses made at a frequency of at least once a week were calculated to compare state and non-state psychiatric services. The 95% confidence intervals of the RRs were calculated using the Koopman asymptotic score method. RESULTS: Responses of 960 Russian psychiatrists were included in the analysis. Of these 95, 89 and 87% reported making diagnoses of MADD, AdD and PD, respectively, during the preceding 12 months, a far larger proportion compared to other disorders of interest. In general, a significantly smaller proportion of participants in our survey made diagnoses of anxiety disorders compared to respondents in the international WPA-WHO survey. Based on RRs, diagnoses of MADD, AdD, PD, GAD and acute stress disorder were less frequently made in the state-operated psychiatric service. CONCLUSION: Our survey revealed a serious underdiagnosis of anxiety disorders in Russia that may be associated with complex factors that include, but are not limited to the current stigma associated with the state-operated psychiatric service, which is still the exclusive source of official statistical data in Russia.

Retrospective surveillance of antibiotic use in maternity wards and neonatal intensive care units in Saint Petersburg, Russia.

Antibiotic overuse in infants is associated with an increased risk of serious adverse events. Development of antibiotic stewardship programs aimed at reducing overall antibiotic consumption requires epidemiological surveillance. Retrospective surveillance and evaluation of all antibiotics provided to every infant admitted to maternal wards or neonatal intensive care units (NICUs) from 01 January 2014 to 31 December 2014 were performed in five medical centers of Saint Petersburg, Russia. Types of antibiotics and dates of administration were recorded. Antibiotic use was quantified by length of therapy (length of therapy, LOT, per 1000 patient-days, PD) and days of therapy (DOT/1000 PD). An additional parameter named "instant DOT/1000 PD" was introduced by authors for assessment of longitudinal patterns of administrations. Antibiotic load was 825.6 DOT/1000 PD in maternity wards and 1425.8 DOT/1000 PD in the NICUs. These levels are two to four times higher than DOTs reported in the USA for a level III NICU (348 DOT/1000PD). Antibiotic load was associated with the length of hospital stay (LOS) and birth weight. These associations were distorted when assessed using the conventional parameters, LOT and DOT, because they do not reflect the longitudinal component of treatment and underestimate antibiotic load when a patient stays in hospital without treatment. The proposed additional parameter successfully overcame these flaws and uncovered hidden associations. Severe overuse of antibiotics may be taking place in Russia and antibiotic stewardship development should be urged. Instant DOT/1000 PD is a more powerful tool in assessing treatment patterns than DOT/1000 PD.