Seasonal influences on admissions for affective disorder and schizophrenia in Ireland: a comparison of first and readmissions

The impact of COVID-19 on acute psychiatric admissions for first and repeated episode psychosis

BACKGROUND

There is limited evidence of the longer-term impact of the COVID-19 pandemic on acute admissions for psychosis in the UK.

AIMS

We examined the impact of COVID-19 on rates of admissions for first and repeated episode psychosis, and changes in patient profile and seasonal patterns, over a period of 12 months.

METHOD

We conducted a retrospective case note review of all patients admitted with a primary psychosis (F20-29 ICD 10 diagnosis) to an NHS psychiatric inpatient unit. We compared the 12 months pre-COVID-19 period between 1 March 2019 and 28 February 2020, and the 12 months post-COVID-19 period between 1 March 2020 and 28 February 2021.

RESULTS

The results showed increase rates of admissions post-COVID-19 in both first and repeated episode psychosis, the patient profile had more females and older age in the repeated episode group, with increased employment rates. Combined group data for both pre- and post-COVID-19 periods showed an increased trend in spring and summer admissions, and even though not statistically significant, more pronounced post-COVID-19.

CONCLUSIONS

Our findings highlight the effect of the COVID-19 pandemic on acute psychosis admissions over a 12-month period. The results provide evidence for the 'stress-pathogenesis' in the context of genetic vulnerability in psychosis. Preventative strategies in the context of the 'stress-pathogenesis model', improved access to and responsiveness within NHS transformation efforts needs to be adjusted to fit local need and environmental changes.

A Systematic Review on the Impact of Seasonality on Severe Mental Illness Admissions: Does Seasonal Variation Affect Coercion?

Coercion in psychiatry is associated mainly with involuntary admissions. The purpose of this study was to investigate the associations between hospital admissions of patients suffering from affective and schizophrenic disorders and seasonality. A systematic literature search using PubMed, Scopus and Google Scholar was conducted, including studies with affective and schizophrenia disorder admissions, published from October 1992 to August 2020. A total of 31 studies were included in the review. Four broad severe mental illness admission categories were identified regarding seasonality: affective disorders, schizophrenia disorders, involuntary admission affective disorders and involuntary admission schizophrenia disorders. There was clear and strong evidence for spring and summer peaks for severe mental illness admissions; data provided for age, gender and involuntary admissions was limited. Seasonality may have a significant effect on the onset and exacerbation of psychopathology of severe mental illness and should be considered as a risk factor in psychiatric admissions, violence and the risk of mental health coercion. A better understanding of the impact of seasonality on severe mental illness will help professionals to provide the best practices in mental health services in order to reduce and prevent psychiatric hospitalizations (especially involuntary admissions) resulting in further coercive measures.

Climatic exposures in childhood and the risk of schizophrenia from childhood to early adulthood

BACKGROUND

Season of birth is a risk factor of schizophrenia, and it is possible that cumulative exposure to climatic factors during childhood affects the risk of schizophrenia. We conducted a cohort study among 365,482 persons born in Finland in 1990-1995 to examine associations of 10-year cumulative exposure to global solar radiation and ambient temperature in childhood with schizophrenia.

METHODS

Data on schizophrenia diagnoses and sociodemographic factors from the Finnish population register and health care register were linked to daily meteorological data using residential information. The study population was followed from age 10 until the first schizophrenia diagnosis, death, emigration or December 31, 2017, whichever came first. Hazard ratios (HR) for the risk of schizophrenia were estimated using Cox proportional hazards model.

RESULTS

Compared to the lowest quintile of global solar radiation or ambient temperature, growing up in the second highest quintile (Q4) was associated with greater risk of schizophrenia. These hazard ratios were attenuated after adjustment for parental mental disorder, parental education, parental income, area-level socioeconomic characteristics and urbanicity (HR = 1.29, 95 % CI 1.06-1.58 for radiation; HR = 1.24, 95 % CI, 1.02-1.52 for temperature). Continuous linear terms evaluated in secondary models suggested a greater risk of schizophrenia at greater childhood exposure to global radiation and ambient temperature, but these associations did not remain in fully adjusted models.

CONCLUSIONS

We found no consistent evidence that cumulative exposure to sunlight and ambient temperature in childhood is associated with the risk of developing schizophrenia. Studies in other populations residing in different latitudes are needed.

Effects of different heat exposure patterns (accumulated and transient) and schizophrenia hospitalizations: a time-series analysis on hourly temperature basis

Growing studies have shown that high temperature is a potential risk factor of schizophrenia occurrence. Therefore, elaborate analysis of different temperature exposure patterns, such as cumulative heat exposure within a time period and transient exposure at a particular time point, is of important public health significance. This study aims to utilize hourly temperature data to better capture the effects of cumulative and transient heat exposures on schizophrenia during the warm season in Hefei, China. We included the daily mean temperature and daily schizophrenia hospitalizations into the distributed lag non-linear model (DLNM) to simulate the exposure-response curve and determine the heat threshold (19.4 °C). We calculated and applied a novel indicator-daily excess hourly heat (DEHH)-to examine the effects of cumulative heat exposure over a day on schizophrenia hospitalizations. Temperature measurements at each time point were also incorporated in the DLNM as independent exposure indicators to analyze the impact of transient heat exposure on schizophrenia. Each increment of interquartile range (IQR) in DEHH was associated with elevated risk of schizophrenia hospitalizations from lag 1 (RR = 1.036, 95% confidence interval (CI): 1.016, 1.057) to lag 4 (RR = 1.025, 95% CI: 1.005, 1.046). Men and people over 40 years old were more susceptible to DEHH. Besides, we found a greater risk of heat-related schizophrenia hospitalizations between 0 a.m. and 6 a.m. This study revealed the adverse effects of accumulated and transient heat exposures on schizophrenia hospitalizations. Our findings need to be further tested in other regions with distinct regional features.

Assessing evidence for seasonality of hospital admissions for schizophrenia in Queensland, Australia: a time series observational study

Most evidence on seasonal admission patterns for schizophrenia derives from the Northern Hemisphere with results from the Southern Hemisphere less documented. This study examines seasonal patterns in hospital admissions due to schizophrenia in Queensland, Australia, a large area that has a range of different climatic features. Daily hospital admissions data for people with the primary diagnosis of schizophrenia were collected from Queensland Health Department for the period from January 1996 to December 2015. A generalised linear regression model with Quasi-Poisson distribution was used to assess seasonal admission patterns across different climatic regions. The evidence for seasonality was also explored in subgroups that had different socio-demographic characteristics or history of prior hospitalisation for psychiatric disorders. Overall, a significant winter pattern (RR 1.05, 95%CI 1.01-1.13) was found with a peak in August (RR 1.08, 95%CI 1.03-1.17) in temperate Southeast Queensland. However, the hot humid North and Far North Queensland showed a peak in October (RR 1.10, 95%CI 1.02-1.22). Males (RR 1.11, 95%CI 1.07-1.14), people aged 40-59 years old (RR 1.10, 95%CI 1.05-1.15) and those who had never married (RR 1.09, 95%CI 1.06-1.12), were Australian by birth (RR 1.07, 95%CI 1.04-1.10) or were unemployed (RR 1.13, 95%CI 1.09-1.18) had significantly higher risk for hospital admissions, particularly during the winter months. The seasonal admission pattern for schizophrenia did not change significantly according to admission status and history of outpatient or community psychiatric treatment. The study found some evidence for seasonality of hospital admissions for schizophrenia that differed from northern tropical to southern temperate regions of Queensland.

Investigating the association between temperature and hospital admissions for major psychiatric diseases: A study in Greece

Evidence has emerged regarding the role of seasonality and several meteorological parameters on bipolar disorder, schizophrenia and depression. We investigated the relationship between ambient and apparent temperature and hospital admissions of major psychiatric diseases in a psychiatric clinic of a General Hospital situated in Northern Greece during 2013-19. Temperature data was provided by the National Observatory of Athens and diagnosis for psychotic, schizophrenic, manic and bipolar and unipolar depression were retrieved from medical records. A total of 783 admissions were recorded. Poisson regression models adjusted for time trends were applied to analyze the impact of temperature on monthly admissions. A summer peak was observed for the bipolar disorder, irrespectively of substance/alcohol use status. Seasonality emerged also for psychotic and schizophrenic patients with a through in winter. An increase of 1 °C in either ambient or apparent temperature was associated with an increase 1-2% in the monthly admissions in most outcomes under investigation. Alcohol and drug abuse did not modify this effect. Although our results indicate effects of temperature on psychiatric admissions, they are not consistent across subgroups populations and need to be replicated by other methodologically superior studies.

Immediate and delayed effects of climatic factors on hospital admissions for schizophrenia in Queensland Australia: A time series analysis

BACKGROUND

Evidence of immediate and delayed effects of climatic drivers on hospital admissions for schizophrenia is limited and inconsistent. We aimed to assess the association between climatic factors and daily hospital admissions for schizophrenia in Queensland, Australia.

METHODS

Daily hospital admissions for schizophrenia from January 1, 1996 to December 31, 2015 in all private and public hospitals of Queensland were obtained from Queensland Health. The association between climatic factors and hospital admissions for schizophrenia were analysed using Generalised Linear Models with Poisson distribution (GLM) and Distributed Lag non-linear Models (DLNM) across different climatic zones.

RESULTS

In South East Queensland, only daily mean temperature showed an immediate negative effect on schizophrenia admissions (RR 0.93, 95%CI 0.90-0.98, p value < 0.001). For other regions, the adverse effect of temperature on hospital admissions was not significant, however, relative humidity (North: RR 1.01, 95%CI 1.00-1.02, p = 0.05) and air pressure (North: RR 1.03, 95%CI 1.00-1.05, p = 0.04; South West: RR 1.01, 95%CI 1.00-1.02, p = 0.05) had an immediate and positive effect on hospital admissions. Moreover, climatic factors had some delayed effects on schizophrenia admissions in different regions of Queensland, i.e. temperature over 0-4 lag days (South East: RR 0.97, 95%CI 0.94-0.98, p = 0.05; South West: RR 0.96, 95%CI 0.94-0.98, p = 0.01), relative humidity over 0-7 lag days (North: RR 0.95, 95%CI 0.92-0.98, p = 0.01; Central: RR 1.02, 95%CI 1.00-1.03, p = 0.05) and rainfall over 0-21 lag days (North: RR 1.03, 95%CI 1.01-1.04, p = 0.01). Meta-analysis showed significant pooled delayed effects of temperature (0-15 days lag: RR 0.95, 95% CI 0.93-0.98, p value < 0.001), relative humidity (0-7 days: RR 0.96, 95%CI 0.92-0.99, p < 0.001); rainfall (0-21 lag days: RR 1.03, 95%CI 1.01-1.04, p < 0.001) and air pressure (0-7 days lag: RR 1.02, 95%CI 1.00-1.04, p < 0.001) on schizophrenia admissions in Queensland.

DISCUSSION

As this is the largest study from Australia and also internationally to extensively examine both short term and delayed association between climatic factors and daily admissions for schizophrenia, the results of the study indicate that climate plays an important role in the sudden exacerbation of acute episodes of schizophrenia. Thus, preventive measures could be taken to reduce the severity of symptoms as well as hospital admissions due to schizophrenia during vulnerable periods.

Cross-sectional and within-subject seasonality and regularity of hospitalizations: A population study in mood disorders and schizophrenia

BACKGROUND

Seasonal peaks in hospitalizations for mood disorders and schizophrenia are well recognized and often replicated. The within-subject tendency to experience illness episodes in the same season, that is, seasonal course, is much less established, as certain individuals may temporarily meet criteria for seasonal course purely by chance.

AIMS

In this population, prospective cohort study, we investigated whether between and within-subject seasonal patterns of hospitalizations occurred more frequently than would be expected by chance.

METHODS

Using a compulsory, standardized national register of hospitalizations, we analyzed all admissions for mood disorders and schizophrenia in the Czech Republic between 1994 and 2013. We used bootstrap tests to compare the observed numbers of (a) participants with seasonal/regular course and (b) hospitalizations in individual months against empirical distributions obtained by simulations.

RESULTS

Among 87 184 participants, we found uneven distribution of hospitalizations, with hospitalization peaks for depression in April and November (X² (11) = 363.66, P < .001), for mania in August (X² (11) = 50.36, P < .001) and for schizophrenia in June (X² (11) = 70.34, P < .001). Significantly more participants than would be expected by chance, had two subsequent rehospitalizations in the same 90 days in different years (7.36%, bootstrap P < .01) or after a regular, but non-seasonal interval (6.07%, bootstrap P < .001). The proportion of participants with two consecutive hospitalizations in the same season was below chance level (7.06%).

CONCLUSIONS

Psychiatric hospitalizations were unevenly distributed throughout the year (cross-sectional seasonality), with evidence for regularity, but not seasonality of hospitalizations within subjects. Our data do not support the validity of seasonal pattern specifier. Season may be a general risk factor, which increases the risk of hospitalizations across psychiatric participants.

Seasonality and schizophrenia: a comprehensive overview of the seasonal pattern of hospital admissions and potential drivers

Schizophrenia is a severe neuropsychiatric disorder with heterogeneous aetiology mostly affecting younger people and causing immense disability. Seasonal patterns may be observed in schizophrenia hospital admissions with possible association with changing climatic parameters and socio-demographic characteristics. This study critically reviewed studies that have assessed seasonal variations of hospital admissions for schizophrenia and/or explored an association with climate parameters and/or other potential factors. Following PRISMA guidelines, a systematic literature search was conducted using electronic databases (e.g. MEDLINE, Science Direct, PsycINFO, Pub Med) from inception to February 29, 2020. Thirty five papers were identified, of which only six (17.1%) examined evidence for a seasonal pattern or monthly excess of hospital admissions and the remaining twenty nine (82.9%) assessed climatic and socio-demographic attributes relating to the seasonal pattern or increased hospitalisation for schizophrenia. While most studies reported a summer peak in hospital admission rates, other studies reported a winter peak. Most of the evidence indicated that higher temperatures (> 28 °C) were positively correlated with schizophrenia admission rates. The individual effects of other climatic parameters (e.g. relative humidity, rainfall, atmospheric pressure, sunlight) were less frequently assessed. Males, people of 21-60 years old, and those married were more vulnerable to climatic variability specifically to higher temperatures. Further studies using large sample sizes, analysis of a wide range of interacting environmental variables and sophisticated statistical approaches are needed to better understand the underlying mechanisms involved. This will also provide more reliable statistical evidence that will help in the prevention and better management of cases.

Seasonality in schizophrenia-An analysis of a nationwide registry with 110,735 hospital admissions

Background.

Seasonal patterns in hospitalizations have been observed in various psychiatric disorders, however, it is unclear whether they also exist in schizophrenia. Previous studies found mixed results and those reporting the presence of seasonality differ regarding the characteristics of these patterns. Further, they are inconclusive whether sex is an influencing factor. The aim of this study was therefore to examine if seasonal patterns in hospitalizations can be found in schizophrenia, with special regard to a possible influence of sex, by using a large national dataset.

Methods.

Data on all hospital admissions within Austria due to schizophrenia (F20.0–F20.6) for the time period of 2003–2016 were included. Age standardized monthly variation of hospitalization for women and men was analyzed and the level of significance adjusted for multiple testing.

Results.

The database comprised of 110,735 admissions (59.6% men). Significant seasonal variations were found in the total sample with hospitalization peaks in January and June and a trough in December (p < 0.0001). No significant difference in these patterns was found between women and men with schizophrenia (p < 0.0001).

Conclusion.

Our study shows that schizophrenia-related hospitalizations follow a seasonal pattern in both men and women. The distribution of peaks might be influenced by photoperiod changes which trigger worsening of symptoms and lead to exacerbations in schizophrenia. Further research is necessary to identify underlying factors influencing seasonal patterns and to assess whether a subgroup of patients with schizophrenia is especially vulnerable to the impact of seasonal variations.

Seasonal and temperature effect on serum lithium concentrations

BACKGROUND

Lithium remains the gold standard treatment for bipolar disorder. However, it has a very narrow therapeutic index (0.6-0.8 mmol/L). It has been suggested that high environmental temperature can lead to dehydration, elevated plasma lithium concentration and then lithium toxicity.

OBJECTIVES

We aimed to investigate the effect of seasonal and short-term changes in temperature on serum lithium concentrations in Sydney, Australia.

METHODS

We retrospectively analysed data from all patients who had serum lithium concentrations taken from the Prince of Wales and Sutherland Hospitals between 2008 and 2018. Temperature data came from the Bureau of Meteorology. We examined correlations between lithium concentrations and the preceding 5 days maximum temperatures, month and season. We also performed a longitudinal analysis of the effect of temperature and seasons within selected patients who had repeated levels.

RESULTS

A total of 11,912 serum lithium concentrations from 2493 patients were analysed. There was no significant association between higher lithium concentration and preceding higher temperatures (r = -0.008, p = 0.399). There was also no important seasonal or monthly variation, across all patients or in the smaller cohort with longitudinal data (n = 123, r = 0.008, 95% confidence interval: [-0.04, 0.06]).

CONCLUSION

There were no clinically important differences in serum lithium concentration related to seasons, months or temperatures, which suggests that patients on lithium are able to adequately maintain hydration during hot weather in Sydney.

Psychological assessment of acute schizophrenia patients who experienced seclusion either alone or in combination with restraint

Objective Numerous studies on the effects of seclusion and/or restraint in acute psychiatric treatment have reported both positive and negative effects. However, no studies to date have evaluated the effects of seclusion and/or restraint on schizophrenia patients using a rating scale. Thus, to examine the effects of seclusion and/or restraint on schizophrenia patients, we used the Brief Psychiatric Rating Scale and assessed the psychological condition of patients. Methods Factor analysis was conducted to create subscales of Brief Psychiatric Rating Scale, and psychiatric changes were assessed with respect to each subscale using multiple logistic regression analyses. Analyses were performed on three groups (i.e. entire, higher functioning, and lower functioning groups) involving a total of 1559 schizophrenia patients aged 18 to 65 years. Results In the entire and lower functioning groups, seclusion was a significant predictor of improvements related to the "hostility/suspiciousness" subscale. Seclusion combined with restraint was associated with improvements related to the "psychosis/thinking disorder" subscale. In the higher functioning group, there were no significant predictors. Conclusions It is implied that seclusion and/or restraint is related to improved psychiatric symptoms only among patients whose functioning is impaired. To verify the present findings, further studies involving multiple sites and additional psychiatric measures are necessary.

The relationship between fine particulate matter (PM2.5) and schizophrenia severity

PURPOSE

Although particulate matter (PM) is reported to affect the rate of emergency admissions for schizophrenia, no study has examined the relationship between particulate matter less than 2.5 μm in diameter (PM_2.5) and the severity of schizophrenia.

METHODS

We obtained data on patients with schizophrenia at a psychiatric hospital, and on air pollution in Sakai, Japan between Feb 1, 2013 and April 30, 2016. Multivariate logistic regression analyses were used to estimate the relationship between PM_2.5 concentrations and scores on the Brief Psychiatric Rating Scale (BPRS) of schizophrenia patients at admission, with a lag of up to 7 days.

RESULTS

During the study period, there were 1193 schizophrenia cases. The odds ratio (OR) for a BPRS score ≥ 50 at admission was 1.05 [95% confidence interval 1.00-1.10] and the effect of PM_2.5 concentration was significant for lag period of 2 days. The ORs associated with PM_2.5 concentration increased substantially for patients over 65 years of age.

CONCLUSIONS

Ambient PM_2.5 concentration was associated with exacerbation of schizophrenia. Our results suggest that protection for several days should be considered for controlling PM_2.5-related schizophrenia, especially among elderly patients.

Impact of short-term temperature variability on emergency hospital admissions for schizophrenia stratified by season of birth

Diurnal temperature range (DTR) and temperature change between neighboring days (TCN) are important meteorological indicators closely associated with global climate change. However, up to date, there have been no studies addressing the impacts of both DTR and TCN on emergency hospital admissions for schizophrenia. We conducted a time-series analysis to assess the relationship between temperature variability and daily schizophrenia onset in Hefei, an inland city in southeast China. Daily meteorological data and emergency hospital admissions for schizophrenia from 2005 to 2014 in Hefei were collected. After stratifying by season of birth, Poisson generalized linear regression combined with distributed lag nonlinear model (DLNM) was used to examine the relationship between temperature variability and schizophrenia, adjusting for long-term trend and seasonality, mean temperature, and relative humidity. Our analysis revealed that extreme temperature variability may increase the risk for schizophrenia onset among patients born in spring, while no such association was found in patients born in summer and autumn. In patients born in spring, the relative risks of extremely high DTR comparing the 95th and 99th percentiles with the reference (50th, 10 °C) at 3-day lag were 1.078 (95 % confidence interval (CI) 1.025-1.135) and 1.159 (95 % CI 1.050-1.279), respectively. For TCN effects, only comparing 99th percentile with reference (50th, 0.7 °C) was significantly associated with emergency hospital admissions for schizophrenia (relative risk (RR) 1.111, 95 % CI 1.002-1.231). This study suggested that exposure to extreme temperature variability in short-term may trigger later days of schizophrenia onset for patients born in spring, which may have important implications for developing intervention strategies to prevent large temperature variability exposure.

The International College of Neuropsychopharmacology (CINP) Treatment Guidelines for Bipolar Disorder in Adults (CINP-BD-2017), Part 1: Background and Methods of the Development of Guidelines

BACKGROUND

This paper includes a short description of the important clinical aspects of Bipolar Disorder with emphasis on issues that are important for the therapeutic considerations, including mixed and psychotic features, predominant polarity, and rapid cycling as well as comorbidity.

METHODS

The workgroup performed a review and critical analysis of the literature concerning grading methods and methods for the development of guidelines.

RESULTS

The workgroup arrived at a consensus to base the development of the guideline on randomized controlled trials and related meta-analyses alone in order to follow a strict evidence-based approach. A critical analysis of the existing methods for the grading of treatment options was followed by the development of a new grading method to arrive at efficacy and recommendation levels after the analysis of 32 distinct scenarios of available data for a given treatment option.

CONCLUSION

The current paper reports details on the design, method, and process for the development of CINP guidelines for the treatment of Bipolar Disorder. The rationale and the method with which all data and opinions are combined in order to produce an evidence-based operationalized but also user-friendly guideline and a specific algorithm are described in detail in this paper.

Involuntary admissions in Italy: the impact of seasonality

OBJECTIVE

The aim of this study is to assess the prevalence of involuntary admissions with regard to seasonality and clinical associated features, in a sample of patients admitted to a psychiatric unit in a period of 24 months.

METHODS

All subjects consecutively admitted to the Psychiatric Inpatient Unit of the San Luigi Gonzaga Hospital, Orbassano (University of Turin, Italy) from September 2013 to August 2015 were recruited. Socio-demographic and clinical characteristics were collected.

RESULTS

Seven hundred and thirty admissions in psychiatric ward were recognized. The prevalence of involuntary admission was 15.4%. Patients with involuntary hospitalizations showed a higher education level, a higher prevalence of admission in spring/summer with a significant peak in June, a longer duration of hospitalization and a lower suicide ideation. Among involuntary admissions, physical restraint and suicide attempts were more prevalent during spring compared to the other seasons.

CONCLUSIONS

Seasonality has an important role in the psychopathology of psychiatric disorders, particularly in bipolar and related disorder, and may represent an influencing factor in hospital admissions and hospitalizations. Seasonal pattern must be considered while managing diagnosis and treatment of mental disorders, with regard to prevention and psychoeducation of patients.

Heatwaves and Hospital Admissions for Mental Disorders in Northern Vietnam

Studies in high-income countries have shown an association between heatwaves and hospital admissions for mental disorders. It is unknown whether such associations exist in subtropical nations like Vietnam. The study aim was to investigate whether hospital admissions for mental disorders may be triggered, or exacerbated, by heat exposure and heatwaves, in a low- and middle-income country, Vietnam. For this, we used data from the Hanoi Mental Hospital over five years (2008–2012) to estimate the effect of heatwaves on admissions for mental disorders. A zero-inflated negative binomial regression model accounting for seasonality, time trend, days of week, and mean humidity was used to analyse the relationship. Heatwave events were mainly studied as periods of three or seven consecutive days above the threshold of 35°C daily maximum temperature (90^th percentile). The study result showed heatwaves increased the risk for admission in the whole group of mental disorders (F00-79) for more persistent heatwaves of at least 3 days when compared with non-heatwave periods. The relative risks were estimated at 1.04 (0.95–1.13), 1.15 (1.005–1.31), and 1.36 (1–1.90) for a one-, three- and seven-day heatwave, respectively. Admissions for mental disorders increased among men, residents in rural communities, and the elderly population during heatwaves. The groups of organic mental disorders, including symptomatic illnesses (F0-9) and mental retardation (F70-79), had increased admissions during heatwaves. The findings are novel in their focus on heatwave impact on mental diseases in a population habituating in a subtropical low- and middle-income country characterized by rapid epidemiological transitions and environmental changes.

The outcomes of psychiatric inpatients by proportion of experienced psychiatrists and nurse staffing in hospital: New findings on improving the quality of mental health care in South Korea

Readmission rates for mental health care are higher in South Korea than other Organization for Economic Development (OECD) countries. Therefore, it is worthwhile to continue investigating how to reduce readmissions. Taking a novel approach, we determined the relationship between psychiatrist experience and mental health care readmission rates. We used National Health Insurance claim data (N=21,315) from 81 hospitals to analyze readmissions within 30 days of discharge for "mood disorders" or "schizophrenia, schizotypal and delusional disorders" during 2010-2013. In this study, multilevel models that included both patient and hospital-level variables were analyzed to examine associations with readmission. Readmissions within 30 days of discharge accounted for 1079 (5.1%) claims. Multilevel analysis demonstrated that the proportion of experienced psychiatrists at a hospital was inversely associated with risk of readmission (OR: 0.79, 95% CI: 0.74-0.84 per 10% increase in experienced psychiatrists). Readmission rates for psychiatric disorders within 30 days of discharge were lower in hospitals with a higher number of nurses (OR: 0.95, 95% CI: 0.94-0.96 per 10 nurses). In conclusion, health policymakers and hospital managers should make an effort to reduce readmissions for psychiatric disorders and other diseases by considering the role that physician experience plays and nurse staffing.

Seasonality shows evidence for polygenic architecture and genetic correlation with schizophrenia and bipolar disorder

OBJECTIVE

To test common genetic variants for association with seasonality (seasonal changes in mood and behavior) and to investigate whether there are shared genetic risk factors between psychiatric disorders and seasonality.

METHOD

Genome-wide association studies (GWASs) were conducted in Australian (between 1988 and 1990 and between 2010 and 2013) and Amish (between May 2010 and December 2011) samples in whom the Seasonal Pattern Assessment Questionnaire (SPAQ) had been administered, and the results were meta-analyzed in a total sample of 4,156 individuals. Genetic risk scores based on results from prior large GWAS studies of bipolar disorder, major depressive disorder (MDD), and schizophrenia were calculated to test for overlap in risk between psychiatric disorders and seasonality.

RESULTS

The most significant association was with rs11825064 (P = 1.7 × 10⁻⁶, β = 0.64, standard error = 0.13), an intergenic single nucleotide polymorphism (SNP) found on chromosome 11. The evidence for overlap in risk factors was strongest for schizophrenia and seasonality, with the schizophrenia genetic profile scores explaining 3% of the variance in log-transformed global seasonality scores. Bipolar disorder genetic profile scores were also associated with seasonality, although at much weaker levels (minimum P value = 3.4 × 10⁻³), and no evidence for overlap in risk was detected between MDD and seasonality.

CONCLUSIONS

Common SNPs of large effect most likely do not exist for seasonality in the populations examined. As expected, there were overlapping genetic risk factors for bipolar disorder (but not MDD) with seasonality. Unexpectedly, the risk for schizophrenia and seasonality had the largest overlap, an unprecedented finding that requires replication in other populations and has potential clinical implications considering overlapping cognitive deficits in seasonal affective disorders and schizophrenia.

Daily weather variables and affective disorder admissions to psychiatric hospitals

Numerous studies have reported that admission rates in patients with affective disorders are subject to seasonal variation. Notwithstanding, there has been limited evaluation of the degree to which changeable daily meteorological patterns influence affective disorder admission rates. A handful of small studies have alluded to a potential link between psychiatric admission rates and meteorological variables such as environmental temperature (heat waves in particular), wind direction and sunshine. We used the Kruskal-Wallis test, ARIMA and time-series regression analyses to examine whether daily meteorological variables--namely wind speed and direction, barometric pressure, rainfall, hours of sunshine, sunlight radiation and temperature--influence admission rates for mania and depression across 12 regions in Ireland over a 31-year period. Although we found some very weak but interesting trends for barometric pressure in relation to mania admissions, daily meteorological patterns did not appear to affect hospital admissions overall for mania or depression. Our results do not support the small number of papers to date that suggest a link between daily meteorological variables and affective disorder admissions. Further study is needed.

Seasonality and bipolar disorder: a systematic review, from admission rates to seasonality of symptoms

INTRODUCTION

Bipolar disorder (BD) is a severe mental disorder affecting 1-4% of the population worldwide. It is characterized by periods of (hypo)manic and depressive episodes. Seasonal patterns (SP) may be observed in admission rates, mood relapses and symptom fluctuations.

METHODS

We conducted a systematic review of seasonality in BD, classifying studies based on seasonal admission rates to seasonality of symptoms assessments.

RESULTS

Fifty-one papers were identified of which 32 addressed hospitalization rates by season, 6 addressed categorical diagnoses, and 13 explored symptom dimensions. Seasonal peaks for different BD mood episodes are observed worldwide and widely replicated. Manic episodes peak during spring/summer and, to a lesser extent, in autumn, depressive episodes peak in early winter and, to a lesser extent, summer, and mixed episodes peak in early spring or mid/late summer. There was a high frequency of SP for manic episodes (15%) and depressive episodes (25%), the latter being associated with a more complex clinical profile (BD II subtype, comorbid eating disorders, more relapses and rapid cycling). Finally, there was evidence for greater seasonal fluctuations in mood and behavior in individuals with BD than in those with unipolar depression or 'healthy' controls.

LIMITATIONS

Sample size, gender distribution, methodological quality and sophistication of the analytical approaches employed varied considerably.

CONCLUSIONS

There is evidence of seasonality in BD, with emerging evidence that climatic conditions may trigger BD symptoms or episodes. A better understanding of the underlying mechanisms would facilitate the development of personalized chronobiological therapeutic and preventive strategies.

An audit of admissions to an acute psychiatric unit

OBJECTIVES

In an era of cost containment in the health services, it is important to endeavour to manage existing resources in the optimum way. This study examines admissions to an acute psychiatric unit in a general hospital in order to identify factors that characterise these admissions, which in turn may suggest appropriate interventions.

METHODS

This was a retrospective casenote review of 105 consecutive admissions. Demographic information and clinical data concerning this admission and service contact in the preceding year was collected. Chi-squared tests were used to compare patients who were admitted during normal working hours with those admitted after 5pm and at weekends. Patients whose length of stay exceeded four weeks were compared with those who had a shorter admission.

RESULTS

Eventually 101 patients were included in the study; of these 46.5% of admissions occurred during normal working hours. Admissions outside this time were more likely to be under 45 years (χ2 = 4.05, df = 1, p 4 weeks duration was more likely in single patients (χ2 = 9.68, df = 2, p <0.01), those living outside the more urban areas (χ2 = 4.04, df = 1, p <0.05) and those who had a diagnosis of a depressive illness or schizophrenia/psychosis (χ2 = 13.43, df = 3, p <0.01). Patients with a diagnosis of alcohol or substance abuse were spending significantly shorter periods in hospital.

CONCLUSIONS

Further development of day hospitals is necessary to provide alternatives to inpatient treatment and facilitate earlier discharge for patients living throughout the catchment area. Alternative methods of service delivery such as outreach programmes should be considered for subgroups of patients who are unable or unwilling to access traditional services. Introducing outpatient detoxification programmes would have a substantial impact on admission patterns in the unit.

The effects of daily weather variables on psychosis admissions to psychiatric hospitals

Several studies have noted seasonal variations in admission rates of patients with psychotic illnesses. However, the changeable daily meteorological patterns within seasons have never been examined in any great depth in the context of admission rates. A handful of small studies have posed interesting questions regarding a potential link between psychiatric admission rates and meteorological variables such as environmental temperature (especially heat waves) and sunshine. In this study, we used simple non-parametric testing and more complex ARIMA and time-series regression analysis to examine whether daily meteorological patterns (wind speed and direction, barometric pressure, rainfall, sunshine, sunlight and temperature) exert an influence on admission rates for psychotic disorders across 12 regions in Ireland. Although there were some weak but interesting trends for temperature, barometric pressure and sunshine, the meteorological patterns ultimately did not exert a clinically significant influence over admissions for psychosis. Further analysis is needed.

Relationship between mean daily ambient temperature range and hospital admissions for schizophrenia: Results from a national cohort of psychiatric inpatients

Environmental temperature is known to correlate with schizophrenia, but little is known about the association with changes in temperature. This 12-year study aimed to evaluate the relationship between the mean daily range of ambient temperature and schizophrenia admissions in a national cohort of psychiatric inpatients in Taiwan. Meteorological data provided by the Central Weather Bureau of Taiwan were interpolated to create representative estimates. Psychiatric inpatient admissions in all hospitals with medical services enrolled in the current health care insurance system were retrieved from the 1996-2007 Psychiatric Inpatient Medical Claim dataset of the National Health Insurance Research Database. Generalized linear models with Poisson distributions were used to analyze the impact of mean diurnal change of temperature on schizophrenia admissions, controlling for internal correlations and demographic covariates. The daily temperature range varied between 1.7°C and 12.1°C (1st to 99th percentile). The relative risk of schizophrenia admission was significantly increased at a temperature range of 3.2°C (10th percentile), and the maximum was at 12.1°C (99th percentile); however, no such association was found with schizoaffective disorder. When restricted to the capital and largest city, the effects of temperature range were prominent and may correlate with temperature itself. The joint effect of temperature and temperature range was associated with elevated risk, particularly at cooler temperatures. A positive correlation was found between increasing temperature range and schizophrenia admissions. The increase in morbidity at high percentiles suggests that the increasing dynamics of temperature range are a valid reflection of risk, highlighting the need for precautionary action.

The role of environmental influences on schizophrenia admissions in Israel

OBJECTIVE

The role of environmental factors in hospitalization of patients with schizophrenia is incompletely understood. This study attempts to relate the pattern of hospital admissions to environmental variables such as season and to social factors such as nationally celebrated holidays.

METHODS

Charts of all adults (n = 4,331) with a discharge diagnosis of schizophrenia admitted to the Abarbanel Mental Health Centre (Bat Yam, Israel) between 1 January 2001 and 31 December 2005 were reviewed. Hospitalizations were classified by gender, first or repeat admission, month and season of admission, and whether or not the admission coincided with a major Jewish holiday period.

RESULTS

There was a significant reduction (p < 0.05) in first admissions for men during April, the month corresponding to Passover, the most widely celebrated holiday in Israel. This pattern was not seen for women or for repeat admissions. There was no significant effect of the season upon admission rates, using two different methods of defining the season.

CONCLUSIONS

This study demonstrated significant monthly variability in admission rates and a possible protective effect of a widely celebrated public religious holiday. A consistent effect of season upon rates of admission was not found. Future studies need to identify which specific social factors exert a protective or harmful effect and study how knowledge of these effects can be translated into clinical practice.

Seasonal variations in bipolar disorder admissions and the association with climate: a population-based study

OBJECTIVE

Although seasonal influences on bipolar disorder admissions have long been observed, the issues of seasonality on different subtypes of mood episodes and the effects of associated climatic parameters remain controversial. This study sets out to examine seasonal variations in bipolar disorder admissions and the association with climate in Taiwan, a subtropical area with fairly constant weather conditions.

METHODS

This retrospective population-based study uses the Taiwan National Health Insurance Research Database for 1999-2003, identifying 15,060 admissions for bipolar disorder, comprising of 8631 manic, 2078 depressive and 4351 mixed/unspecified episodes. The auto-regressive integrated moving average model was applied to examine the presence of seasonality and the association with climate in each subtype of mood episodes.

RESULTS

Admission peaks were noted during spring/summer, early winter and early spring, for manic, depressive and mixed/unspecified episodes, respectively, while the associations with climatic parameters varied between the subtypes of mood episodes.

CONCLUSIONS

Seasonality in bipolar disorder does exist for all subtypes of mood episodes. The distinct seasonal patterns and various associations with the climatic parameters imply different underlying mechanisms for the onset of each subtype of mood episodes. The association between admission rates and certain climatic variables found in this study is informative and could pave the way for future studies aimed at exploring the influence of climate on the psychopathology of bipolar patients as well as the underlying mechanisms.

Seasonal influences on first-episode admission in affective and non-affective psychosis

BACKGROUND

Since bipolar affective disorder has been recorded, clinicians treating patients with this disorder have noted the cyclic nature of episodes, particularly an increase in mania in the spring and summer months and depression during winter.

OBJECTIVE

The aim of this study was to investigate seasonality in symptom onset and service admissions over a period of 10 years in a group of patients (n= 359) with first-episode (FE) mania (n= 133), FE schizoaffective disorder (n= 49) and FE schizophrenia (n= 177).

METHOD

Patients were recruited if they were between 15 and 28 years of age and if they resided in the geographical mental health service catchment area. The number of patients experiencing symptom onset and service admission over each month and season was recorded.

RESULTS

In terms of seasonality of time of service admission, the results indicate a high overall seasonality (particularly in men), which was observed in both the schizoaffective and the bipolar groups. In terms of seasonality of symptom onset, the results indicate that seasonality remains in the male bipolar group, but other groups have no seasonal trend.

CONCLUSIONS

This provides further evidence that systems mediating the entrainment of biological rhythms to the environment may be more pronounced in BPAD than in schizoaffective disorder and schizophrenia. These results may help facilitate the preparedness of mental heath services for patients at different times of the year.

Distinct seasonality of depressive episodes differentiates unipolar depressive patients with and without depressive mixed states

BACKGROUND

The bipolar nature of unipolar depression with depressive mixed states (DMX) needs further validation studies. The seasonality of depressive episodes is indicated to be different between unipolar and bipolar depressions. We therefore explored the seasonal pattern of depressive episodes in unipolar depressive patients with DMX.

METHODS

The subjects were 958 consecutive depressive inpatients for a 6-year period. For defining DMX, previously validated operational criteria were used (2 or more of 8 manic or mania-related symptoms: flight of idea, logorrhea, aggression, excessive social contact, increased drive, irritability, racing thoughts, and distractibility). Onsets of the index depressive episodes during each of the 12 calendar months were summed up over the 6-year for bipolar depressive patients (N = 95), and unipolar depressive patients with (N = 77) and without DMX (N = 786) separately. An appropriate statistic was used for testing seasonality.

RESULTS

A significant seasonal variation with a large peak in spring was recognized in unipolar depression without DMX, while both bipolar depression and unipolar depression with DMX had a significant fall peak. The monthly distribution of depressive episodes was significantly different between unipolar depression without DMX and other 2 diagnostic categories. Similar results were obtained in separate analyses for each gender.

LIMITATIONS

Further replication study using an epidemiological or outpatient sample is needed. Bipolar I and II patients were combined due to a small number of bipolar II patients in this sample.

CONCLUSION

Unipolar depression with DMX has a seasonal pattern similar to bipolar depression. The finding provides further evidence of the bipolar nature of unipolar depression with DMX.

Seasonality in a community sample of bipolar, unipolar and control subjects

BACKGROUND

This study examined seasonality in a community sample of five diagnostic groups: normal subjects, those with non-seasonal depression (NSD), seasonal depression (SD), non-seasonal bipolar disorder (NSBD) and seasonal bipolar disorder (SBD).

METHODS

Telephone interviews were conducted across the Province of Ontario. Seasonal changes in mood and behaviour were determined using the Seasonal Pattern Assessment Questionnaire (SPAQ). Five additional seasonality items consisting of depressive symptoms were included in the interview. The mean global severity of seasonality (GSS) scores were obtained and the entire inventory of 11 seasonality items were compared across the identified groups.

RESULTS

The mean GSS score for the controls was 5.2 (S.D. = 4.0), 8.0 (S.D. = 4.9) for NSD, 10.5 (S.D. = 3.9) for SD, 10.5 (S.D. = 5.4) for NSBD and 13.4 (S.D. = 5.4) for SBD. These scores differed significantly (F = 61.68, df = 4, p < 0.001). For the majority of the individual items, the SBD group rated the highest degree of seasonal fluctuation, while the NSBD and SD groups had nearly identical item scores.

LIMITATIONS

Limitations in this study include the relatively small number of subjects in the NSBD and SBD groups, and the inherent limitations in a telephone interview.

CONCLUSIONS

Individuals with bipolar disorder experience greater seasonality than those with depression or healthy controls. Even the non-seasonal bipolar group had as much seasonal fluctuation as the seasonal depression group, which has important implications for the management of bipolar illness.

Influence of season and latitude in a community sample of subjects with bipolar disorder

OBJECTIVE

To report on the prevalence of seasonal bipolar disorder (BD) and the impact of latitude in a community sample in the province of Ontario.

METHOD

This study used the telephone-administered Depression and Seasonality Interview. Exact latitude was determined for each participant.

RESULTS

Overall, 14 of 62 (22.6%) subjects with BD had the seasonal subtype of BD. Latitude did not appear to influence the proportion of subjects with the seasonal subtype.

CONCLUSIONS

We identified a seasonal pattern of illness in a proportion of subjects with BD.

Evidence that latitude is directly related to variation in suicide rates

OBJECTIVE

To use available suicide-rate data from 20 countries to see patterns and relations more clearly.

METHOD

We obtained raw suicide rates from the Organization for Economic Cooperation and Development (OECD) database from 1960 through 1997 and calculated averages and standard deviations.

RESULTS

There is a positive linear relation between the variation in suicide rate and geographic latitude.

CONCLUSIONS

The variation in light-dark cycles is superimposed upon human mood.