Climatic factors and bipolar affective disorder

Sensitivity to Climate and Weather Changes in Euthymic Bipolar Subjects: Association With Suicide Attempts

BACKGROUND

Climate and weather are known to affect multiple areas of human life, including mental health. In bipolar disorder (BD), seasonality represents an environmental trigger for mood switches, and climatic variables may contribute to recurrences. Several studies reported seasonal and climatic-related variations in the rate of suicide attempts. Suicide risk is relevant in BD, with approximately 25% of patients attempting suicide. Therefore, this study aimed to assess sensitivity to weather and climatic variations in BD subjects and its relationship with lifetime suicide attempts.

METHODS

Three hundred fifty-two euthymic BD and 352 healthy control subjects, homogeneous with respect to socio-demographic characteristics, were enrolled. All participants were administered the METEO-Questionnaire (METEO-Q) to evaluate susceptibility to weather and climatic changes. We also investigated the potential relationship between sensitivity to climate and weather and lifetime suicide attempts in BD patients.

RESULTS

METEO-Q scores and the number of subjects reaching the cut-off for meteorosensitivity/meteoropathy were significantly higher in BD patients. Within the clinical group, BD subjects with lifetime suicide attempts obtained higher METEO-Q scores, with no differences between BD-I and BD-II. The number of suicide attempts directly correlated with METEO-Q scores. The presence of suicide attempts was associated with the physical and psychological symptoms related to weather variations.

DISCUSSION

Our findings support the relevance of sensitivity to weather and climate variations in a large sample of BD subjects and point out the association of this feature with lifetime suicide attempts.

Maximum Temperature and Solar Radiation as Predictors of Bipolar Patient Admission in an Emergency Psychiatric Ward

Environmental variables can regulate behavior in healthy subjects. Recently, some authors investigated the role of meteorological variables in bipolar patients with an impact on both the onset and course of bipolar disorder (BD). The aim of this study was to investigate the impact of meteorological variables and other indexes in bipolar hospitalized patients. We examined all patients admitted to the Psychiatric Inpatient Unit of San Luigi Gonzaga Hospital, Orbassano (Turin, Italy) from September 2013 to August 2015, collecting several socio-demographic and clinical characteristics. Seven hundred and thirty patients were included. Compared to the day of admission of control individuals, patients with BD were admitted on a day that presented higher minimum, medium, and maximum temperature, higher maximum humidity, higher solar radiation, and higher hours of sunshine. After logistic regression analysis, admissions to the emergency psychiatric ward due to a primary diagnosis of BD were associated with maximum temperature and solar radiation. The current study provides a novel perspective on the question surrounding seasonal mood patterns in patients with BD. A greater awareness of all possible precipitating factors is needed to inform self-management and psycho-educational programs as well as to improve resilience regarding affective recurrences in the clinical practice.

Investigating the effect of climatic parameters on mental disorder admissions

The main objective of this study was to evaluate the role of climatic parameters and phenomena including the monthly number of dusty/rainy/snowy/foggy days, cloudiness (Okta), horizontal visibility, and barometric pressure (millibar) on major depressive disorder, bipolar, schizophrenia, and schizoaffective admissions. The monthly data related to the number of admissions in Farshchian hospital and climatic parameters from March 2005 to March 2017 were extracted. Random forest regression and dynamic negative binomial regression were used to examine the relationship between variables; the statistical significance was considered as 0.05. The number of dusty/rainy/snowy/foggy days, cloudiness, and the number of days with vision less than 2 km had a significant positive relationship with admissions due to schizophrenia (p < 0.05). Barometric pressure had a negative effect on schizophrenia admissions (p < 0.001). The number of dusty/rainy/snowy/foggy days and cloudiness had a significant effect on schizoaffective admissions (p < 0.05). Bipolar admissions were negatively associated with rainy days and positively associated with dusty days and cloudiness (p < 0.05). The number of rainy/dusty/snowy days and cloudiness had a positive significant effect on major depressive disorder admissions. The results of the present study confirmed the importance of climatic parameter variability for major depressive disorder, bipolar, schizophrenia, and schizoaffective admissions.

Meteorological parameters and air pollen count in association with self-reported peripartum depressive symptoms

BACKGROUND

Meteorological parameters and air pollen count have been associated with affective disorders and suicide. Regarding peripartum depression, the literature is restricted and inconclusive.

METHODS

This cross-sectional study included women (pregnant, n = 3843; postpartum, n = 3757) who participated in the BASIC (Biology, Affect, Stress, Imaging, and Cognition) study 2010-2015 and the UPPSAT (Uppsala-Athens) study (postpartum, n = 1565) in 2006-2007. Cases were defined according to presence of depressive symptoms during pregnancy (gestational week 32) and 6 weeks postpartum, using the Edinburgh Postnatal Depression Scale (EPDS). Exposure of sunshine, temperature, precipitation, snow coverage, and air pollen counts of durations of 1, 7, and 42 days prior to the outcome were studied for associations with depressive symptoms, using negative binomial regression.

RESULTS

Prior to Bonferroni correction, the concentration of mugwort pollen, both one week and six weeks before the EPDS assessment at gestational week 32, was inversely associated with depressive symptoms in pregnancy, both before and after adjustment for season. No associations were found between the exposure to meteorological parameters and pollen and depressive symptoms, at the same day of depressive symptoms' assessment, the previous week, or the six weeks prior to assessment, either during pregnancy or postpartum after Bonferroni correction.

CONCLUSIONS

There was no evidence that neither short-term nor long-term exposure to meteorological parameters or air pollen counts were associated with self-reported peripartum depressive symptoms in Uppsala, Sweden.

Highs and lows, ups and downs: Meteorology and mood in bipolar disorder

Seasonal variation of manic and depressive symptoms is a controversial topic in bipolar disorder research. Several studies report seasonal patterns of hospital admissions for depression and mania and variation in symptoms that appear to follow a seasonal pattern, whereas others fail to report such patterns. Differences in research methodologies, data analysis strategies, and temporal resolution of data may partly explain the variation in findings between studies. The current study adds a novel perspective to the literature by investigating specific meteorological factors such as atmospheric pressure, hours of sunshine, relative humidity, and daily maximum and minimum temperatures as more proximal predictors of self-reported daily mood change in people diagnosed with bipolar disorder. The results showed that daily maximum temperature was the only meteorological variable to predict clinically-relevant mood change, with increases in temperature associated with greater odds of a transition into manic mood states. The mediating effects of sleep and activity were also investigated and suggest at least partial influence on the prospective relationship between maximum temperature and mood. Limitations include the small sample size and the fact that the number and valence of social interactions and exposure to natural light were not investigated as potentially important mediators of relationships between meteorological factors and mood. The current data make an important contribution to the literature, serving to clarify the specific meteorological factors that influence mood change in bipolar disorder. From a clinical perspective, greater understanding of seasonal patterns of symptoms in bipolar disorder will help mood episode prophylaxis in vulnerable individuals.

Seasonality of Admissions for Mania: Results From a General Hospital Psychiatric Unit in Pondicherry, India

INTRODUCTION

Bipolar disorder is affected by variables that modulate circadian rhythm, including seasonal variations. There is evidence of a seasonal pattern of admissions of mania in various geographical settings, though its timing varies by region and climate. Variables such as age and gender have been shown to affect seasonality in some studies.

METHODOLOGY

Data on monthly admission patterns for mania at a general hospital psychiatry unit in Pondicherry, India, were collected for 4 years (2010-2013) and analyzed for seasonality and seasonal peaks. The effects of age and gender were analyzed separately.

RESULTS

There was overall evidence of a seasonal pattern of admissions for mania (P < .01, Friedman test for seasonality), with a peak beginning during the rainy season and ending before summer (P < .0.1, Ratchet circular scan test). Male sex (P < .005, Ratchet circular scan test) and age > 25 years (P < .005, Ratchet circular scan test) were specifically associated with this seasonal peak.

DISCUSSION

The effect of seasons on mania is complex and is modulated by a variety of variables. Our study is consistent with earlier research findings: a greater degree of seasonality for mania in men. It is possible that climatic and individual variables interact to determine seasonal patterns in bipolar disorder in a given setting.

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.

Is there a role for "climatotherapy" in the sustainable development of mental health?

Climate, diet, lifestyle, and environmental settings have all been shown to modulate mood, play a role in mental disorders, and even pose a mental health risk. Can climatotherapy, in its adaptive approach aiming to restore balance among the economic, social, and ecological realms of human societies, situate itself as a therapeutic avenue for the promotion of sustainable mental health?

Evidence for seasonal mania: a review

OBJECTIVE

The goal of this article is to summarize the evidence for seasonal mania based on research studies and findings concerning interrelationships among circadian rhythm, manic episodes, and mood stabilizers.

METHODS

The PubMed database was searched using the key word "seasonal mania." This search generated a list of 197 papers published between 1990 and 2011, 29 of which were original research studies on seasonal mania. The findings from these studies were reviewed with regard to their relevance to the mechanisms involved in seasonal mania and strategies for managing mania.

RESULTS

Of the 29 research studies, the majority (n=23) provided evidence for a significant seasonal pattern for mania, while the other 6 studies did not. Most of the studies reported that mania occurred more often during spring and summer and that depression occurred more often during fall and winter. The authors of the studies estimated a prevalence of seasonal mania of 15% among patients with bipolar disorder. It is hypothesized that the underlying mechanism for seasonal mania may be hypersensitivity to bright light that suppresses melatonin production. Both lithium and valproate can counteract the action of bright light in suppressing melatonin and prolong sleep-wake cycles in the circadian rhythms of patients with bipolar disorder. These effects may at least partially explain their efficacy as mood stabilizing agents. No research studies were located that provided information on managing the medication regimen, especially of mood stabilizing medications, based on the seasonal patterns seen in some patients with bipolar disorder in order to reduce the risk of relapse associated with seasonal mania. Positive findings in this area might lead to a new paradigm for the management of patients with bipolar disorder who have seasonal mania.

Relationship among latitude, climate, season and self-reported mood in bipolar disorder

OBJECTIVE

Many researchers have analyzed seasonal variation in hospital admissions for bipolar disorder with inconsistent results. We investigated if a seasonal pattern was present in daily self-reported daily mood ratings from patients living in five climate zones in the northern and southern hemispheres. We also investigated the influence of latitude and seasonal climate variables on mood.

METHOD

360 patients who were receiving treatment as usual recorded mood daily (59,422 total days of data). Both the percentage of days depressed and hypomanic/manic, and the episodes of depression and mania were determined. The observations were provided by patients from different geographic locations in North and South America, Europe and Australia. These data were analyzed for seasonality by climate zone using both a sinusoidal regression and the Gini index. Additionally, the influence of latitude and climate variables on mood was estimated using generalized linear models for each season and month.

RESULTS

No seasonality was found in any climate zone by either method. In spite of vastly different weather, neither latitude nor climate variables were associated with mood by season or month.

CONCLUSION

Daily self-reported mood ratings of most patients with bipolar disorder did not show a seasonal pattern. Neither climate nor latitude has a primary influence on the daily mood changes of most patients receiving medication for bipolar disorder.