Risk of mortality from suicide in patients with Huntington's disease is increased compared to the general population in England

Risk Factors and Interventions for Suicide in Huntington's Disease-A Systematic Review

Background/Objectives: Huntington's disease (HD) is an autosomal dominant genetic disorder causing progressive neurodegeneration which, aside from symptomatic therapies for controlling psychological and motor problems, currently has no effective treatment. People who receive this diagnosis often feel disoriented and lost without guidance. Furthermore, HD patients are estimated to have a two to seven times greater risk of suicide death compared to the general population. The current review investigates the complex relationship between HD and suicide, seeking to identify key risk factors influencing suicidal ideation and behaviour in affected individuals. Methods: We conducted a systematic review following the PRISMA guidelines. Studies were searched for on the PubMed, Cochrane, and Web of Science databases, and 17 articles met the inclusion criteria. Results: The findings reveal that emotional strain, neuropsychiatric symptoms, and the absence of a cure contribute to heightened suicidal tendencies in HD patients. Critical periods for suicide risk coincide with early symptomatic stages of disease or the successive phase, with the loss of independence impacting on daily functioning. Risk factors associated with HD include a depressive mood, cognitive impairments, and a history of suicide attempts. Conclusions: From a prevention perspective, a comprehensive multidisciplinary and multidimensional approach could enhance the overall well-being of people with HD. In particular, screening for suicidal thoughts in people with HD could mitigate suicide risk.

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.

The microbiota-gut-brain axis in Huntington's disease: pathogenic mechanisms and therapeutic targets

Huntington's disease (HD) is a currently incurable neurogenerative disorder and is typically characterized by progressive movement disorder (including chorea), cognitive deficits (culminating in dementia), psychiatric abnormalities (the most common of which is depression), and peripheral symptoms (including gastrointestinal dysfunction). There are currently no approved disease-modifying therapies available for HD, with death usually occurring approximately 10-25 years after onset, but some therapies hold promising potential. HD subjects are often burdened by chronic diarrhea, constipation, esophageal and gastric inflammation, and a susceptibility to diabetes. Our understanding of the microbiota-gut-brain axis in HD is in its infancy and growing evidence from preclinical and clinical studies suggests a role of gut microbial population imbalance (gut dysbiosis) in HD pathophysiology. The gut and the brain can communicate through the enteric nervous system, immune system, vagus nerve, and microbiota-derived-metabolites including short-chain fatty acids, bile acids, and branched-chain amino acids. This review summarizes supporting evidence demonstrating the alterations in bacterial and fungal composition that may be associated with HD. We focus on mechanisms through which gut dysbiosis may compromise brain and gut health, thus triggering neuroinflammatory responses, and further highlight outcomes of attempts to modulate the gut microbiota as promising therapeutic strategies for HD. Ultimately, we discuss the dearth of data and the need for more longitudinal and translational studies in this nascent field. We suggest future directions to improve our understanding of the association between gut microbes and the pathogenesis of HD, and other 'brain and body disorders'.

Assisted deaths in Switzerland for UK residents: diagnoses and their implications for palliative medicine and assisted dying legislation

OBJECTIVE

UK campaigners for a law permitting assisted dying (AD) restricted to those with a maximum life expectancy of 6 months claim that this would largely remove the need for UK residents to seek AD in Switzerland. We wanted to discover whether this prediction was correct.

METHODS

We analysed the diagnoses of UK residents who had such deaths including, for the first time, data from all three of the main Swiss providers of AD to non-residents, comparing them with figures from Oregon, which has a 6-month restriction.

RESULTS

Only 22.7% of UK residents had cancer (Oregon 72.5%) while nearly half (49.6% and over half including dementias) had neurological conditions (Oregon 11.2%) and many with prognoses of much more than 6 months.

CONCLUSION

Overall, less than half would meet a 6-month prognosis criterion. This has significant implications for patients, palliative care clinicians and legislators.

Huntington's Disease-Related Mortality Patterns: A Two-Decade Analysis of Mortality Trends in the United States, from 1999-2019

Background

Huntington's disease (HD) is an autosomal dominant, progressive neurodegenerative disorder debilitating mainly in adults.

Objective

This study aimed to assess the trends in HD-related mortality regarding various demographic factors.

Methods

Death certificates from the CDC WONDER were studied from 1999 to 2019, for HD-related mortality in adults aged 25 + years. Age-adjusted Mortality Rate (AAMR) per 100,000 persons and Annual Percentage Change (APC) were calculated and stratified by year, age groups, gender, race/ethnicity, state, census region, urbanization, and place of death.

Results

Between 1999 to 2019, 22,595 deaths occurred in adults due to HD. The AAMR increased from 0.43 to 0.54 during this period (APC = 0.50; 95% CI: 0.18 to 0.84). Old adults (65-85 + years) had the highest overall AAMR, followed by middle-aged adults (45-64 years) and young adults (25-44 years) (AAMR old: 1.01 vs. AAMR middle-age: 0.68 vs. AAMR young: 0.16). Men had slightly greater overall AAMRs than women (AAMR men: 0.54 vs. AAMR women: 0.48). When stratified by race, non-Hispanic (NH) Whites had significantly higher mortality rates than NH African Americans (AAMR NH White: 0.61 vs. NH African American: 0.35), while the AAMR were lowest in Hispanic/Latino (0.28). The AAMRs also showed variation by region (overall AAMR: Midwest: 0.63, Northeast: 0.47, West: 0.48, South: 0.46), and non-metropolitan areas had higher HD-related AAMR (0.66) than metropolitan areas (0.47).

Conclusions

HD-related mortality in US adults has increased since 1999. Reflecting on the variations in trends observed, new strategies are required to optimize the quality of care in long-term care facilities.

The flavonoid luteolin reduces mutant huntingtin aggregation and cytotoxicity in huntingtin-mutated neuroblastoma cells

Background

Huntington's disease is an inherited progressive neurodegenerative disorder caused by an expansion of the polyglutamine tract leading to malformation and aggregation of the mutant huntingtin protein in the cell cytoplasm and nucleus of affected brain regions. The development of neuroprotective agents from plants has received considerable research attention.

Objective

Our study aims to investigate the neuroprotective effects of luteolin and the mechanisms that underline its potential mediated protection in the mutant htt neuroblastoma cells.

Methods

The mutant htt neuroblastoma cells were transfected with 160Q, and the control wild-type neuroblastoma cells were transfected with 20Q htt for 24 h and later treated with luteolin. Cell viability was determined by MTT and PI staining in both groups, while western blotting was used to evaluate caspase 3 protein expression. Aggregation formation was assessed via immunofluorescence microscopy. Also, western blotting was utilized to measure the protein expression of mutant htt aggregated and soluble protein, Nrf2 and HO-1. The impact of Nrf2 on luteolin-treated neuroblastoma cells was assessed using small interfering RNAs.

Results

Our study reports that luteolin can protect cultured cells from mutant huntingtin cytotoxicity, evidenced by increased viability and decreased apoptosis. Also, luteolin reduced the accumulation of soluble and insoluble mutant huntingtin aggregates in mutant htt neuroblastoma cells transfected with 160Q compared to the control wild-type. The mutant htt aggregate reduction mediated by luteolin appeared to be independent of the Nrf2 -HO-1 antioxidant pathway.

Conclusion

Luteolin presents a new potential therapeutic and protective agent for the treatment and decreasing the cytotoxicity in neurodegenerative diseases such as Huntington's disease.

Risk of Suicide After Dementia Diagnosis

Importance

Patients with dementia may be at an increased suicide risk. Identifying groups at greatest risk of suicide would support targeted risk reduction efforts by clinical dementia services.

Objectives

To examine the association between a dementia diagnosis and suicide risk in the general population and to identify high-risk subgroups.

Design, Setting, and Participants

This was a population-based case-control study in England conducted from January 1, 2001, through December 31, 2019. Data were obtained from multiple linked electronic records from primary care, secondary care, and the Office for National Statistics. Included participants were all patients 15 years or older and registered in the Office for National Statistics in England with a death coded as suicide or open verdict from 2001 to 2019. Up to 40 live control participants per suicide case were randomly matched on primary care practice and suicide date.

Exposures

Patients with codes referring to a dementia diagnosis were identified in primary care and secondary care databases.

Main Outcomes and Measures

Odds ratios (ORs) were estimated using conditional logistic regression and adjusted for sex and age at suicide/index date.

Results

From the total sample of 594 674 patients, 580 159 (97.6%) were controls (median [IQR] age at death, 81.6[72.0-88.4] years; 289 769 male patients [50.0%]), and 14 515 (2.4%) died by suicide (median [IQR] age at death, 47.4 [36.0-59.7] years; 10 850 male patients [74.8%]). Among those who died by suicide, 95 patients (1.9%) had a recorded dementia diagnosis (median [IQR] age at death, 79.5 [67.1-85.5] years; median [IQR] duration of follow-up, 2.3 [1.0-4.4] years). There was no overall significant association between a dementia diagnosis and suicide risk (adjusted OR, 1.05; 95% CI, 0.85-1.29). However, suicide risk was significantly increased in patients diagnosed with dementia before age 65 years (adjusted OR, 2.82; 95% CI, 1.84-4.33), in the first 3 months after diagnosis (adjusted OR, 2.47; 95% CI, 1.49-4.09), and in patients with dementia and psychiatric comorbidity (adjusted OR, 1.52; 95% CI, 1.21-1.93). In patients younger than 65 years and within 3 months of diagnosis, suicide risk was 6.69 times (95% CI, 1.49-30.12) higher than in patients without dementia.

Conclusions and Relevance

Diagnostic and management services for dementia, in both primary and secondary care settings, should target suicide risk assessment to the identified high-risk groups.