Possible Association of Cholesterol as a Biomarker in Suicide Behavior

Higher suicide risk in type 1 diabetes compared to cancer and the general population in Korea

BACKGROUND

People with diabetes have increased suicide risk. However, it is unclear whether those with type 1 diabetes (T1D) have a higher risk than those with cancer, a disease associated with significant psychological stress and suicide risk.

OBJECTIVES

To evaluate suicide risk among adults with T1D compared to matched cohorts of patients with cancer and the general population.

METHODS

This population-based matched-cohort study examined adults aged ≥19 years (45,944 with T1D and 45,944 with cancer matched for age, sex, and index year) using data from the Korean National Health Insurance Database for January 2009-December 2015 and including 229,720 matched controls without diabetes or cancer (1:5). Composite suicide outcomes were death by suicide or hospitalization for a suicide attempt (intentional self-harm, fatal toxic substance, toxic effect of carbon monoxide, psychotropic medication, wrist laceration, fall, and asphyxia).

RESULTS

Participants had a median age of 62 years and a median follow-up duration of 10.3 years. T1D was significantly associated with an increased risk of composite suicide outcomes (adjusted hazard ratio [aHR] = 2.02; 95% confidence interval [CI] = 1.87-2.19) compared to controls. Individuals with T1D had significantly higher composite suicide outcome risk than patients with cancer (1:1) (aHR = 1.75; 95% CI = 1.55-1.97). Younger (Age < 50) and lower-income patients with T1D had a higher suicide risk than those without diabetes or cancer.

CONCLUSION

This nationwide study demonstrated a significant association between T1D and increased suicide risk compared to the general population and patients with cancer. This underscores the importance of mental health screening and targeted interventions for this population.

Genetic Architecture of Postpartum Psychosis: From Common to Rare Genetic Variation

Postpartum psychosis is a severe psychiatric condition marked by the abrupt onset of psychosis, mania, or psychotic depression following childbirth. Despite evidence for a strong genetic basis, the roles of common and rare genetic variation remain poorly understood. Leveraging data from Swedish national registers and genomic data from the All of Us Research Program, we estimated family-based heritability at 55% and WGS-based heritability at 37%, with an overrepresentation on the X chromosome. Rare coding variant analysis identified DNMT1 and HMGCR as potential risk genes (q < 0.1). Analysis of 240,009 samples from All of Us demonstrated significant associations between these genes and multiple psychiatric disorders, supporting their biological relevance. Additionally, 17% of bipolar disorder, 21% of schizophrenia, and 16-25% of multiple autoimmune disorder risk genes overlapped with postpartum psychosis. These findings reveal unique genetic contributions and shared pathways, providing a foundation for understanding pathophysiology and advancing therapeutic strategies.

Association between fluctuations in blood cholesterol levels and the risk of suicide death in the general population

OBJECTIVE

Suicide is a pressing global public health issue. While recent studies have explored the association between serum cholesterol levels and suicide risk, the association between cholesterol variability and suicide risk is not well characterized.

METHODS

This was a nationwide population-based cohort study using data from the Korean National Health Insurance Service database. A total of 1,983,701 patients with at least three measurements of TC between 2004 and 2009 were included. Participants were followed until death by suicide or the study's end in December 2021. Participants were categorized based on baseline TC or TC variability. TC variability was assessed using coefficient of variation (CV), variability independent of the mean (VIM), and average successive variability (ASV).

RESULTS

Over a median follow-up of 11 years, 5883 (0.3 %) patients died by suicide. Compared to subjects with TC <200 mg/dL, those with TC ≥240 mg/dL had a lower risk of suicide death (hazard ratio [HR]: 0.85, 95 % confidence interval [95 % CI]: 0.78-0.93). In the unadjusted model, the HR for suicide death in the highest quartile (Q4) compared to the lowest quartile (Q1) of TC variability was 1.36 (95 % CI: 1.26-1.46). After adjusting for potential confounders, high variability in TC levels was associated with a higher risk of suicide death (HR 1.27, 95 % CI: 1.18-1.37). When analyzed based on the combination of TC baseline and variability, the highest quartile of TC variability showed a higher rate of suicide death compared to the lowest quartile, regardless of baseline TC level.

CONCLUSION

High TC variability and low TC levels were associated with an increased risk of suicide.

Population-attributable fraction of psychiatric and physical disorders for suicide among older adults in Taiwan

BACKGROUND

This study aimed to estimate the population-attributable fraction (PAF) of psychiatric and physical disorders for suicide among older adults, focusing on sex- and age-specific factors.

METHODS

Data from Taiwan's National Health Insurance Research Data and National Death Registry included 9136 cases of suicide in individuals aged 65+, with 89,439 matched controls. Physical and psychiatric disorders were identified through diagnostic records. Conditional logistic regression assessed risk factors, and PAF was calculated using disorder prevalence and adjusted odds ratios.

RESULTS

Major suicide risk factors among older adults were depressive disorders, anxiety disorders, and sleep disorders. Physical disorders like hypertension, peptic ulcers, and cancer also showed significant PAF values. The combined PAF of physical disorders equaled that of psychiatric disorders. Psychiatric disorders had a greater impact on women and the youngest-old adults, while physical disorders had a higher contribution among men, middle-old adults, and oldest-old adults.

LIMITATIONS

Relying solely on claim data to identify psychiatric and physical disorders may underestimate their prevalence and associations with suicide due to unrecorded cases of individuals not seeking help and the absence of key risk factors like social isolation and family support.

CONCLUSIONS

This study identifies preventable or treatable risk factors for older adult suicide, emphasizing the need to target specific psychiatric and physical disorders in suicide prevention efforts while taking into account sex- and age-specific considerations. It also underscores the importance of establishing social welfare support systems to address the unique challenges older adults face.

The Relationship Between CYP46A1 Polymorphism and Suicide Risk: A Preliminary Investigation

Suicide is a global public health issue, with a particularly high incidence in individuals suffering from Major Depressive Disorder (MDD). The role of cholesterol in suicide risk remains controversial, prompting investigations into genetic markers that may be implicated. This study examines the association between CYP46A1 polymorphisms, specifically SNPs rs754203 and rs4900442, and suicide risk in a Mexican MDD patient cohort. Our study involved 188 unrelated suicide death victims, 126 MDD patients, and 144 non-suicidal controls. Genotypic and allelic frequencies were assessed using the Real Time-polymerase chain reaction method, and associations with suicide risk were evaluated using chi-square tests. The study revealed significant differences in allelic and genotypic frequencies in rs754203 SNP between suicide death and controls. The CYP46A1 rs754203 genotype G/G was significantly linked with suicide, and the G allele was associated with a higher risk of suicide (OR = 1.370, 95% CI = 1.002-1.873). However, we did not observe any significant differences in genotype distribution or allele frequencies of CYP46A1 rs4900442. Our study suggests that carriers of the CYP46A1 rs754203 G allele (A/G + G/G) may play a role in suicidal behavior, especially in males. Our findings support that the CYP46A1 gene may be involved in susceptibility to suicide, which has not been investigated previously. These results underscore the importance of further research in different populations to elucidate the genetic underpinnings of the role of CYP46A1 in suicide risk and to develop targeted interventions for at-risk populations.

Neurological, Metabolic, and Psychopathological Correlates of Lifetime Suicidal Behaviour in Major Depressive Disorder without Current Suicide Ideation

INTRODUCTION

Suicidal behaviour (SB) has a complex aetiology. Although suicidal ideation (SI) is considered the most important risk factor for future attempts, many people who engage in SB do not report it.

METHODS

We investigated neurological, metabolic, and psychopathological correlates of lifetime SB in two independent groups of patients with major depression (sample 1: n = 230; age: 18-65 years; sample 2: n = 258; age >60 years) who did not report SI during an index episode.

RESULTS

Among adults (sample 1), SB was reported by 141 subjects (58.7%) and severe SB by 33 (15%). After controlling for interactions, four risk factors for SB emerged: male gender (OR 2.55; 95% CI: 1.06-6.12), negative self-perception (OR 1.76; 95% CI: 1.08-2.87), subthreshold hypomania (OR 4.50; 95% CI: 1.57-12.85), and sexual abuse (OR 3.09; 95% CI: 1.28-7.48). The presence of at least two of these factors had the best accuracy in predicting SB: sensitivity = 57.6% (39.2-74.5); specificity = 75.1% (68.5-82.0); PPV = 27.9% (20.9-37.2); NPV = 91.4% (87.6-94.1). In older patients (sample 2), 23 subjects (9%) reported previous suicide attempts, which were characterized by earlier onset (25 years: OR 0.95: 0.92-0.98), impaired verbal performance (verbal fluency: OR 0.95: 0.89-0.99), higher HDL cholesterol levels (OR 1.04: 1.00-1.07) and more dyskinesias (OR 2.86: 1.22-6.70).

CONCLUSION

Our findings suggest that SB is common in major depressive disorder, even when SI is not reported. In these individuals it is feasible and recommended to investigate both psychiatric and organic risk factors. The predictive power of models excluding SI is comparable to that of models including SI.