Chris Cornell, the Black Hole Sun, and the Seasonality of Suicide

Fell on Black Days: Analyzing the Song Lyrics of Chris Cornell for Insight into Depression and Suicide

Chris Cornell was a guitarist, singer, songwriter, and pioneer of grunge music. Cornell struggled with mental illness and addiction and incorporated these themes into his song lyrics. At age 52, Cornell died by suicide in his hotel bathroom following a live performance. This mixed-methods study examines Cornell's song lyrics for references to negative words and themes related to depression and suicide. Two coders independently reviewed lyrical transcripts to identify the primary theme, secondary theme(s), and valence (positive or negative). Sentiment analysis, a natural language processing technique, was used to examine word frequency and valence. Songs (N = 215) were predominantly (79%) negative and contained more negative (N = 3244, 56.1%) than positive (N = 2537, 43.9%) words. Thematic analysis by stage of career shows a narrowing focus on depression, failed relationships, and morbid thoughts. Themes of depressed mood, death, and suicide were common and increased by stage of career. By applying qualitative and quantitative techniques to song lyrics, this study revealed that Cornell's songs reflect a narrative of negativity consistent with someone experiencing depression and thoughts of death and suicide. Like personal notes and poems, song lyrics may reflect symptoms of depression and suicidal thoughts warranting clinical attention.

Variations in seasonal solar insolation are associated with a history of suicide attempts in bipolar I disorder

Background

Bipolar disorder is associated with circadian disruption and a high risk of suicidal behavior. In a previous exploratory study of patients with bipolar I disorder, we found that a history of suicide attempts was associated with differences between winter and summer levels of solar insolation. The purpose of this study was to confirm this finding using international data from 42% more collection sites and 25% more countries.

Methods

Data analyzed were from 71 prior and new collection sites in 40 countries at a wide range of latitudes. The analysis included 4876 patients with bipolar I disorder, 45% more data than previously analyzed. Of the patients, 1496 (30.7%) had a history of suicide attempt. Solar insolation data, the amount of the sun’s electromagnetic energy striking the surface of the earth, was obtained for each onset location (479 locations in 64 countries).

Results

This analysis confirmed the results of the exploratory study with the same best model and slightly better statistical significance. There was a significant inverse association between a history of suicide attempts and the ratio of mean winter insolation to mean summer insolation (mean winter insolation/mean summer insolation). This ratio is largest near the equator which has little change in solar insolation over the year, and smallest near the poles where the winter insolation is very small compared to the summer insolation. Other variables in the model associated with an increased risk of suicide attempts were a history of alcohol or substance abuse, female gender, and younger birth cohort. The winter/summer insolation ratio was also replaced with the ratio of minimum mean monthly insolation to the maximum mean monthly insolation to accommodate insolation patterns in the tropics, and nearly identical results were found. All estimated coefficients were significant at p < 0.01.

Conclusion

A large change in solar insolation, both between winter and summer and between the minimum and maximum monthly values, may increase the risk of suicide attempts in bipolar I disorder. With frequent circadian rhythm dysfunction and suicidal behavior in bipolar disorder, greater understanding of the optimal roles of daylight and electric lighting in circadian entrainment is needed.

Do psychiatric diseases follow annual cyclic seasonality?

Seasonal affective disorder (SAD) famously follows annual cycles, with incidence elevation in the fall and spring. Should some version of cyclic annual pattern be expected from other psychiatric disorders? Would annual cycles be similar for distinct psychiatric conditions? This study probes these questions using 2 very large datasets describing the health histories of 150 million unique U.S. citizens and the entire Swedish population. We performed 2 types of analysis, using “uncorrected” and “corrected” observations. The former analysis focused on counts of daily patient visits associated with each disease. The latter analysis instead looked at the proportion of disease-specific visits within the total volume of visits for a time interval. In the uncorrected analysis, we found that psychiatric disorders’ annual patterns were remarkably similar across the studied diseases in both countries, with the magnitude of annual variation significantly higher in Sweden than in the United States for psychiatric, but not infectious diseases. In the corrected analysis, only 1 group of patients—11 to 20 years old—reproduced all regularities we observed for psychiatric disorders in the uncorrected analysis; the annual healthcare-seeking visit patterns associated with other age-groups changed drastically. Analogous analyses over infectious diseases were less divergent over these 2 types of computation. Comparing these 2 sets of results in the context of published psychiatric disorder seasonality studies, we tend to believe that our uncorrected results are more likely to capture the real trends, while the corrected results perhaps reflect mostly artifacts determined by dominantly fluctuating, health-seeking visits across a given year. However, the divergent results are ultimately inconclusive; thus, we present both sets of results unredacted, and, in the spirit of full disclosure, leave the verdict to the reader.

Should we expect psychiatric disorders to show a cyclic annual pattern? This study reveals that psychiatric diseases’ annual patterns were remarkably similar across the studied diseases in both the US and Sweden, with the magnitude of annual variation significantly higher in Sweden than in the US for psychiatric, but not infectious, diseases.

Identification of socio-demographic, occupational, and societal factors for guiding suicide prevention: A cohort study of Swiss male workers (2000-2014)

INTRODUCTION

We modeled suicidal rate among Swiss working-age males, considering three groups of factors at socio-demographic, occupational, and societal levels jointly. Our goal was twofold: to verify the effect of occupation after adjustment for non-occupational factors and to identify protective and risk factors relevant for suicide prevention in working male adults.

METHODS

The study population included all men aged [18-65] years at the 2000 population census and followed up within the Swiss National Cohort (SNC). The risk of suicide was modeled using Poisson regression.

RESULTS

The cohort comprised 1,534,564 men and 4371 deaths by suicide. Suicide rate varied significantly according to age, civil status, nationality, highest education achieved, and socio-professional category at socio-demographic level; occupation, occupational activity branch, weekly working hours, and home-to-work commute time at occupational level; calendar period of death, region, religious affiliation, and volunteering activity at societal level. After adjustment for non-occupational factors, agricultural and fishery laborers, military and civil security workers, and health and social workers were identified as high-risk groups with respect to suicide.

CONCLUSION

This study evidenced a complex web of factors at socio-demographic, occupational, and societal levels behind the suicide in Swiss male workers and identified the most at-risk groups, deserving targeted prevention efforts.

Seasonality of suicide: a multi-country multi-community observational study

AIMS

We aimed to investigate the heterogeneity of seasonal suicide patterns among multiple geographically, demographically and socioeconomically diverse populations.

METHODS

Weekly time-series data of suicide counts for 354 communities in 12 countries during 1986-2016 were analysed. Two-stage analysis was performed. In the first stage, a generalised linear model, including cyclic splines, was used to estimate seasonal patterns of suicide for each community. In the second stage, the community-specific seasonal patterns were combined for each country using meta-regression. In addition, the community-specific seasonal patterns were regressed onto community-level socioeconomic, demographic and environmental indicators using meta-regression.

RESULTS

We observed seasonal patterns in suicide, with the counts peaking in spring and declining to a trough in winter in most of the countries. However, the shape of seasonal patterns varied among countries from bimodal to unimodal seasonality. The amplitude of seasonal patterns (i.e. the peak/trough relative risk) also varied from 1.47 (95% confidence interval [CI]: 1.33-1.62) to 1.05 (95% CI: 1.01-1.1) among 12 countries. The subgroup difference in the seasonal pattern also varied over countries. In some countries, larger amplitude was shown for females and for the elderly population (≥65 years of age) than for males and for younger people, respectively. The subperiod difference also varied; some countries showed increasing seasonality while others showed a decrease or little change. Finally, the amplitude was larger for communities with colder climates, higher proportions of elderly people and lower unemployment rates (p-values < 0.05).

CONCLUSIONS

Despite the common features of a spring peak and a winter trough, seasonal suicide patterns were largely heterogeneous in shape, amplitude, subgroup differences and temporal changes among different populations, as influenced by climate, demographic and socioeconomic conditions. Our findings may help elucidate the underlying mechanisms of seasonal suicide patterns and aid in improving the design of population-specific suicide prevention programmes based on these patterns.

Prevalence of somatic and psychiatric morbidity across occupations in Switzerland and its correlation with suicide mortality: results from the Swiss National Cohort (1990-2014)

BACKGROUND

Suicide is a major and complex public health problem. In Switzerland, suicide accounts for about 1000 deaths yearly and is the fourth leading cause of mortality. The first nationwide Swiss study of suicides identified eight male and four female occupations with statistically significant excess of suicide compared to the general Swiss population. Working time, self-employer status, low socio-economic status and low skill level required for occupation were associated with increase in suicide risk. Presently, we aim to compare the distribution of suicide risk across occupations with the prevalence of somatic and psychiatric morbidity in Swiss working-aged adults. We hypothesized that some diseases would cluster in particular occupations, indicating potential work-relatedness of suicides found in these occupations.

METHODS

We used the Swiss National Cohort (SNC) and included 10575 males and 2756 females deceased by suicide between 1990 and 2014. We estimated the prevalence of 16 categories of concomitant diseases in each occupation, using national mortality records, and assessed the homogeneity of diseases distribution across occupations. For diseases, which prevalence varied significantly across occupations, we analyzed the correlation with the distribution of suicide risk, estimated as the standardized mortality ratio (SMR) of suicide.

RESULTS

Mental and behavioral disorders were the most commonly reported concomitant diseases in our population. In men, the prevalence of these disorders and more specifically, the prevalence of substance-related and addictive disorders, and of psychotic disorders varied significantly across occupations and was correlated with the SMR of suicide. The prevalence of malignant neoplasms and the prevalence of diseases of the musculoskeletal system and connective tissue also varied significantly across male occupations, while in women, such a variation was observed for neoplasms of uncertain or unknown behavior and diseases of the nervous system and sense organs, without being correlated with the SMR of suicide.

CONCLUSION

Some of the identified morbidities can be occupation-related and could negatively affect the working capacity and the employability, which in turn could be related to the suicide. Disentangling concomitant diseases according to their work-relatedness and relationship with the suicide risk is important for identifying occupation-related suicides, understanding their characteristics, and developing appropriated interventions for their prevention.