Risks of major mental disorders after parental death in children, adolescents, and young adults and the role of premorbid mental comorbidities: a population-based cohort study

Previous studies have shown an association between early parental death and the risk of subsequent major mental disorders (MMDs) among the bereaved children and adolescents; however, it is unclear whether this risk exists in young adults and in individuals with premorbid mental comorbidities. We aimed to explore differences between children, adolescents, and young adults in the risk of MMDs after parental death. We analyzed data from the Taiwan National Health Research Database. The index cohort was offspring (divided into four groups: aged < 6, 6-11, 12-17, and 18-29 years) whose parents had died. The control cohort was demographically matched offspring whose parents were still alive. Cox regression with adjustments for demographics was used to estimate the risk of subsequent MMDs between the index and control cohorts, including schizophrenia, bipolar disorder, and depressive disorder. We included 202,837 cases and 2,028,370 matched controls. As with the bereaved children and adolescents, the bereaved young adults had a significantly higher risk of schizophrenia (hazard ratio with 95% confidence interval: 5.63; 5.01-6.33), bipolar disorder (3.37; 2.96-3.84), and depressive disorder (2.78; 2.68-2.90) than the control cohort. The risk of MMDs was similar for maternal death and paternal death. Among premorbid mental comorbidities, bereaved individuals with premorbid substance use disorder were associated with the highest risk of schizophrenia (10.43; 8.57-12.71), bipolar disorder (12.93; 10.59-15.79), and depressive disorder (10.97; 10.22-11.78). Healthcare workers should be aware that young adults and individuals with premorbid mental comorbidities are at a higher risk of subsequent MMDs than those without premorbid mental comorbidities after parental death.

Cancer Risk in Patients With Bipolar Disorder and Unaffected Siblings of Such Patients: A Nationwide Population-Based Study

Increasing evidence suggests that patients with bipolar disorder are more likely to develop malignant cancer than is the general population. However, the overall cancer risk in the unaffected siblings of such patients remains unknown. From the National Health Insurance Research Database of Taiwan, 25,356 patients with bipolar disorder, 25,356 age-matched unaffected siblings of patients with bipolar disorder, and 101,422 age-matched controls without severe mental disorders between 1996 and 2010 were enrolled in this study. Patients who developed cancer between the time of enrollment and the end of 2011 were identified. Cancers were divided into 3 subgroups based on the related layer of embryonic development: ectodermal, mesodermal, and endodermal cancers. Patients with bipolar disorder (odds ratio [OR] = 1.22, 95% confidence interval [CI]: [1.06, 1.40]) and unaffected siblings of such patients (OR = 1.17, 95% CI [1.02, 1.34]) had greater risk of developing malignant cancer than did controls. Furthermore, only those aged <50 years, for both patients with bipolar disorder (OR = 1.90, 95% CI [1.38, 2.61]) and unaffected siblings (OR = 1.65, 95% CI [1.19, 2.28]), were more likely to develop the ectodermal cancer, especially breast cancer, than the control group. The associations of bipolar disorder and susceptibility to bipolar disorder with increased cancer risk in the younger population may imply a genetic overlap in neurodevelopment and malignancy pathogenesis. Our findings may encourage clinicians to monitor cancer risk factors and warning sings closely in patients with bipolar disorder and in unaffected siblings of such patients. This article is protected by copyright. All rights reserved.

Is one or two infusions better in the first week of low-dose ketamine treatment for medication-resistant depression? A post hoc pooled analysis of randomized placebo-controlled and open-label trials

BACKGROUND

Whether a second ketamine infusion in the first week improves the antidepressant, antisuicidal, and anti-inflammatory effects of the first low-dose ketamine infusion remains unclear.

METHODS

A total of 78 patients with medication-resistant depression were allocated to receive two ketamine infusions (n = 30; days 1 and 4), a single ketamine infusion (n = 24; only day 1), or normal saline placebo infusion (n = 24; only day 1). The Montgomery-Asberg Depression Scale (MADRS) and 17-item Hamilton Rating Scale for Depression (HDRS) were administered before and at 40 min, 240 min, day 2, day 4, day 5, and day 7 after infusion. Serum concentrations of interleukin (IL)-2 and tumor necrosis factor (TNF)-α were assessed.

RESULTS

Two ketamine infusions improved the overall depressive symptoms (p < 0.001) and melancholic symptoms (p < 0.001) than a single ketamine or placebo infusion. The antisuicidal effect did not differ between the ketamine treatment groups. Two ketamine infusions increased TNF-α levels compared with a single ketamine or placebo infusion (p = 0.015). A single ketamine infusion improved the TNF-α-to-IL-2 ratio, an index of average anti-inflammatory effect, than two ketamine infusions or a single placebo infusion (p = 0.027).

DISCUSSION

Repeated low-dose ketamine infusions improved the antidepressant effect, but not the antisuicidal effect, compared with a single infusion. However, repeated ketamine infusions may exert a lesser anti-inflammatory effect than a single infusion.

Bipolar women's antepartum psychotropic exposure and offspring risk of attention-deficit/hyperactivity disorder and autism spectrum disorder

BACKGROUND

Women with bipolar disorder (BD) may continue psychotropics during pregnancy. The association of exposure to antidepressant, antipsychotics, and mood stabilizers with offspring risks of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) remains unexplored in mothers with BD.

METHODS

A total of 5669 pregnant women with BD and 5669 psychiatrically healthy controls were identified between 2002 and 2011 from the Taiwan Longitudinal Health Insurance Database. We analyzed the odds ratios (ORs) of psychotropic types and exposure periods (3 months before pregnancy [3MbPreg] and first, second, and third trimesters [T1, T2, T3, respectively]) on the risk of ADHD and ASD by using adjusted logistic regression analyses.

RESULTS

Antidepressant exposure during 3MbPreg (OR=2.15, 95% CI=1.45-3.20), T1 (OR=2.62, 95% CI=1.68-4.09), T2 (OR=2.33, 95% CI=1.18-4.63), and T3 (OR=2.33, 95% CI=1.67-6.61) was associated with increased offspring risk of ADHD, particularly for selective serotonin reuptake inhibitor and serotonin norepinephrine reuptake inhibitor. Mood stabilizer exposure during 3MbPreg increased the risks of ADHD (OR=2.39, 95% CI=1.45-3.95) and ASD (OR=3.89, 95% CI=1.30-11.65); a higher ADHD risk was associated with valproic acid (OR=2.43, 95% CI=1.32-4.47) and lamotrigine exposure (OR=8.24, 95% CI = 1.49-45.67); ASD risk was higher for lithium exposure (OR=6.75, 95% CI=1.41-32.28).

LIMITATION

In claims-data analyses, several clinical parameters or potential confounders may be incompletely captured.

CONCLUSIONS

Antidepressants were associated with higher offspring risk of ADHD over all gestation periods among mothers with BD than psychiatrically healthy controls, while mood stabilizers were associated with higher risk of ADHD and ASD during 3MbPreg.

Diagnostic progression to bipolar disorder in 17,285 adolescents and young adults with attention deficit hyperactivity disorder: A longitudinal follow-up study

OBJECTIVE

We investigated the diagnostic progression to bipolar disorder (BD) among adolescents and young adults with attention-deficit/hyperactivity disorder (ADHD).

METHODS

Using the Taiwan National Health Insurance Research Database, we enrolled adolescents and young adults aged 10-29 years with ADHD between January 1, 2001, and December 31, 2010, who were followed up until December 31, 2011, to determine progression to BD. Cox regression analysis was used to examine candidate risk and protective factors.

RESULTS

At the 11-year follow-up, the progression rate from ADHD to BD was 5.12%. Of the participants who progressed, 62.16% (322/518) progressed within the first 3 years. Risk factors for progression were as follows: older age (hazard ratio [HR], 1.058; 95% confidence interval [CI], 1.033-1.084), comorbidity with autistic spectrum disorder (HR, 1.839; 95% CI, 1.415-2.391), disruptive behavior disorder (HR, 1.434; 95% CI, 1.132-1.816), intelligence disability (HR, 1.744; 95% CI, 1.399-2.176), depressive disorder (HR, 1.978; 95% CI, 1.577-2.482), alcohol use disorder (HR, 1.705; 95% CI, 1.057-2.751), cluster A (HR, 2.508; 95% CI, 1.167-5.391) or B (HR, 2.718; 95% CI, 1.974-3.741) personality disorder, and a family history of BD (HR, 2.618; 95% CI, 1.823-3.758) Identified protective factors were male sex (HR, 0.771; 95% CI, 0.630-0.943) and cluster C personality disorder (HR, 0.278; 95% CI, 0.086-0.898).

CONCLUSION

The study demonstrated the specific risk and protective factors for BD progression among adolescents and young adults with ADHD. It is important for clinician and mental health care providers to recognize identified factors to focus on early detection and prompt intervention.

Low-dose ketamine infusion for treating subjective cognitive, somatic, and affective depression symptoms of treatment-resistant depression

BACKGROUNDS

Whether the antidepressant effects of low-dose ketamine infusion and the therapeutic impact of Val66Met brain-derived neurotrophic factor (BDNF) polymorphism vary across different depression symptom domains, namely affective, cognitive, and somatic, remains unclear.

METHODS

We-reanalyzed the data of Adjunctive Ketamine Study of Taiwanese Patients with Treatment-Resistant Depression (TRD). A total of 71 patients with TRD were randomized to three infusion groups: 0.5 and 0.2 mg/kg ketamine groups and the normal saline placebo group. The Beck Depression Inventory-II (BDI-II) was used to obtain self-reported scores prior to infusion and 240 min after infusion and sequentially on days 3, 7, and 14 after infusion. The three-factor model of cognitive, somatic, and affective depressive symptoms that is based on the BDI-II and proposed by Beck et al. was applied in the current study. The Val66Met BDNF polymorphism was genotyped.

RESULTS

Ketamine infusion exerted rapid and sustained antidepressant effects on the affective (p = 0.014) and cognitive (p = 0.005) depression symptom domains but not on the somatic (p = 0.085) depression symptom domain. Only patients with TRD harboring any Val allele at the BDNF rs6265 polymorphism were more likely to respond (p = 0.011) to low-dose ketamine infusion.

DISCUSSION

Additional studies should elucidate different mechanisms underlying the effects of ketamine infusion on cognitive, affective, and somatic depression symptom domains in patients with TRD.

Alteration of power law scaling of spontaneous brain activity in schizophrenia

Nonlinear dynamical analysis has been used to quantify the complexity of brain signal at temporal scales. Power law scaling is a well-validated method in physics that has been used to describe the dynamics of a system in the frequency domain, ranging from noisy oscillation to complex fluctuations. In this research, we investigated the power-law characteristics in a large-scale resting-state fMRI data of schizophrenia and healthy participants derived from Taiwan Aging and Mental Illness cohort. We extracted the power spectral density (PSD) of resting signal by Fourier transform. Power law scaling of PSD was estimated by determining the slope of the regression line fitting to the logarithm of PSD. t-Test was used to assess the statistical difference in power law scaling between schizophrenia and healthy participants. The significant differences in power law scaling were found in six brain regions. Schizophrenia patients have significantly more positive power law scaling (i.e., more homogenous frequency components) at four brain regions: left precuneus, left medial dorsal nucleus, right inferior frontal gyrus, and right middle temporal gyrus and less positive power law scaling (i.e., more dominant at lower frequency range) in bilateral putamen compared with healthy participants. Moreover, significant correlations of power law scaling with the severity of psychosis were found. These findings suggest that schizophrenia has abnormal brain signal complexity linked to psychotic symptoms. The power law scaling represents the dynamical properties of resting-state fMRI signal may serve as a novel functional brain imaging marker for evaluating patients with mental illness.

Connectivity-Based Topographical Changes of the Corpus Callosum During Aging

Background: The corpus callosum (CC) is the most prominent white matter connection for interhemispheric information transfer. It is implicated in a variety of cognitive functions, which tend to decline with age. The region-specific projections of the fiber bundles with microstructural heterogeneity of the CC are associated with cognitive functions and diseases. However, how the CC is associated with the information transfer within functional networks and the connectivity changes during aging remain unclear. Studying the CC topography helps to understand the functional specialization and age-related changes of CC subregions. Methods: Diffusion tractography was used to subdivide the CC into seven subregions from 1,086 healthy volunteers within a wide age range (21-90 years), based on the connections to the cortical parcellations of the functional networks. Quantitative diffusion indices and connection probability were calculated to study the microstructure differences and age-related changes in the CC subregions. Results: According to the population-based probabilistic topography of the CC, part of the default mode network (DMN) and limbic network (LN) projected fibers through the genu and rostrum; the frontoparietal network (FPN), ventral attention network (VA) and somatomotor networks (SM) were interconnected by the CC body; callosal fibers arising from the part of the default mode network (DMN), dorsal attention network (DA) and visual network (VIS) passed through the splenium. Anterior CC subregions interconnecting DMN, LN, FPN, VA, and SM showed lower fractional anisotropy (FA) and higher mean diffusivity (MD) and radial diffusivity (RD) than posterior CC subregions interconnecting DA and VIS. All the CC subregions showed slightly increasing FA and decreasing MD, RD, and axial diffusivity (AD) at younger ages and opposite trends at older ages. Besides, the anterior CC subregions exhibited larger microstructural and connectivity changes compared with the posterior CC subregions during aging. Conclusion: This study revealed the callosal subregions related to functional networks and uncovered an overall "anterior-to-posterior" region-specific changing trend during aging, which provides a baseline to identify the presence and timing of callosal connection states.

Association of Alopecia Areata and the Risk of Dementia: A Nationwide Cohort Study

Background: Alopecia areata (AA) is associated with multiple comorbidities and shares a similar inflammatory signature with dementia. The great negative psychosocial impact of AA may result in poor social engagement, a typical risk factor for dementia. However, little is known about the association between AA and dementia. Methods: Via the Taiwan National Health Insurance Research Database, 2,534 patients with AA (International Classification of Diseases, 9th Revision, Clinical Modification code: 704.01) aged ≥ 45 years and 25,340 controls matched for age, sex, residence, income, dementia-related comorbidities, systemic steroid use, and annual outpatient visit were included between 1998 and 2011 for investigation of subsequent dementia from enrollment to the end of 2013. After controlling for potential confounders, stratified Cox regression analysis on each matched pair was applied to assess the dementia risk between the AA and control groups. Results: Patients with AA were more likely to develop any dementia (adjusted hazard ratio [aHR]  = 3.24; 95% CI, 2.14-4.90), Alzheimer's disease (aHR = 4.34; 95% CI, 1.45-12.97), and unspecified dementia (aHR = 3.36; 95% CI, 2.06-5.48) than the control cohort. Stratification analysis by age and sex revealed increased risks of any dementia and unspecified dementia in both age groups (ie, < 65 and ≥ 65 years) and both sex groups and increased risks of AD in male patients and in those with age at dementia onset ≥ 65 years. Sensitivity analyses after exclusion of the first year or first 3 years of observation showed consistent findings. Conclusions: Patients with AA had a higher risk of developing dementia. Further studies are needed to elucidate the underlying pathophysiology between AA and dementia risk.

Neurofilament Light Chain Is a Novel Biomarker for Major Depression and Related Executive Dysfunction

BACKGROUND

Evidence suggests that major depressive disorder is related to neuroaxonal injury and that neurofilament light chain (NfL) is a biomarker of neuroaxonal injury. In addition, proinflammatory cytokines have been reported to be associated with major depression and neuroaxonal injury.

METHODS

Forty patients with major depression and 40 age- and sex-matched healthy control participants were enrolled for the measurement of NfL and proinflammatory cytokines and assessment of executive function. General linear models were used to examine the association between NfL levels, proinflammatory cytokine levels, and executive function.

RESULTS

Patients with major depressive disorder exhibited significantly higher NfL levels (P = .007) than the control participants. NfL levels were positively related to log-transformed levels of tumor necrosis factor-α (P = .004). Higher levels of NfL (P = .002) and tumor necrosis factor-α (P = .013) were associated with greater deficits in executive function.

DISCUSSION

NfL was a novel biomarker for major depressive disorder and related executive dysfunction. Further studies are necessary to elucidate the role of NfL in the pathophysiology of major depression and related cognitive impairment.

Effects of treatment refractoriness and brain-derived neurotrophic factor Val66Met polymorphism on antidepressant response to low-dose ketamine infusion

Evidence suggests that levels of treatment refractoriness and brain-derived neurotrophic factor (BDNF) rs6265 polymorphism are related to the antidepressant effects of conventional antidepressants and repetitive transcranial magnetic stimulation. However, whether these factors are associated with the antidepressant effects of low-dose ketamine remains unclear. In total, 71 patients with treatment-resistant depression (TRD) were randomized to 0.5 mg/kg ketamine, 0.2 mg/kg ketamine, and saline control infusion groups. They were further divided into three treatment refractoriness groups according to the Maudsley staging method and were genotyped for Val66Met BDNF polymorphism. Participants' Hamilton Depression Rating Scale (HDRS) scores were assessed preinfusion, at 40, 80, 120, and 240 min postinfusion, and sequentially on days 2-7 and 14 after infusion. Patients with any Val allele exhibited an antidepressant response (p = 0.029) to 0.5 mg/kg ketamine vs. 0.2 mg/kg ketamine vs. saline control infusions. However, the trajectory of HDRS scores did not differ (p = 0.236) between the treatment groups among Met/Met carriers. In the low treatment refractoriness group, the 0.2 mg/kg ketamine infusion exhibited the optimal antidepressant effect (p = 0.002); in the moderate treatment refractoriness group, the 0.5 mg/kg ketamine infusion achieved the strongest antidepressant effect (p = 0.006); however, in the high treatment refractoriness group, the trajectory of depressive symptoms did not differ between treatments (p = 0.325). In future clinical practice, ketamine dose may be adjusted according to the level of treatment refractoriness and BDNF rs6265 polymorphism to achieve the optimal antidepressant effect for patients with TRD.

An association study in the Taiwan Biobank elicits the GABAA receptor genes GABRB3, GABRA5, and GABRG3 as candidate loci for sleep duration in the Taiwanese population

Background

Gamma-aminobutyric acid type A (GABAA) receptors mainly mediate the effects of gamma-aminobutyric acid, which is the primary inhibitory neurotransmitter in the central nervous system. Abundant evidence suggests that GABAA receptors play a key role in sleep-regulating processes. No genetic association study has explored the relationships between GABAA receptor genes and sleep duration, sleep quality, and sleep timing in humans.

Methods

We determined the association between single-nucleotide polymorphisms (SNPs) in the GABAA receptor genes GABRA1, GABRA2, GABRB3, GABRA5, and GABRG3 and sleep duration, sleep quality, and sleep timing in the Taiwan Biobank with a sample of 10,127 Taiwanese subjects. There were 10,142 subjects in the original study cohort. We excluded 15 subjects with a medication history of sedative-hypnotics.

Results

Our data revealed an association of the GABRB3-GABRA5-GABRG3 gene cluster with sleep duration, which has not been previously identified: rs79333046 (beta = − 0.07; P = 1.21 × 10^–3) in GABRB3, rs189790076 (beta = 0.92; P = 1.04 × 10^–3) in GABRA5, and rs147619342 (beta = − 0.72; P = 3.97 × 10^–3) in GABRG3. The association between rs189790076 in GABRA5 and sleep duration remained significant after Bonferroni correction. A variant (rs12438141) in GABRB3 was also found to act as a potential expression quantitative trait locus. Additionally, we discovered interactions between variants in the GABRB3-GABRA5-GABRG3 gene cluster and lifestyle factors, such as tea and coffee consumption, smoking, and physical activity, that influenced sleep duration, although some interactions became nonsignificant after Bonferroni correction. We also found interactions among GABRB3, GABRA5, and GABRG3 that affected sleep duration. Furthermore, we identified an association of rs7165524 (beta = − 0.06; P = 2.20 × 10^–3) in GABRA5 with sleep quality and an association of rs79465949 (beta = − 0.12; P = 3.95 × 10^–3) in GABRB3 with sleep timing, although these associations became nonsignificant after Bonferroni correction. However, we detected no evidence of an association of individual SNPs in GABRA1 and GABRA2.

Conclusions

Our results indicate that rs189790076 in GABRA5 and gene–gene interactions among GABRB3, GABRA5, and GABRG3 may contribute to sleep duration in the Taiwanese population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-021-01083-x.

Baseline Working Memory Predicted Response to Low-Dose Ketamine Infusion in Patients with Treatment-Resistant Depression

INTRODUCTION

Pretreatment neurocognitive function may predict the treatment response to low-dose ketamine infusion in patients with treatment-resistant depression (TRD). However, the association between working memory function at baseline and the antidepressant efficacy of ketamine infusion remains unclear.

METHODS

A total of 71 patients with TRD were randomized to one of three treatment groups: 0.5 mg/kg ketamine, 0.2 mg/kg ketamine, or normal saline. Depressive symptoms were measured using the 17-item Hamilton Depression Rating Scale (HDRS) at baseline and after treatment. Cognitive function was evaluated using working memory and go-no-go tasks at baseline.

RESULTS

A generalized linear model with adjustments for demographic characteristics, treatment groups, and total HDRS scores at baseline revealed only a significant effect of working memory function (correct responses and omissions) on the changes in depressive symptoms measured by HDRS at baseline (F=12.862, p<0.05). Correlation analysis further showed a negative relationship (r=0.519, p=0.027) between pretreatment working memory function and changes in HDRS scores in the 0.5 mg/kg ketamine group.

DISCUSSION

An inverse relationship between pretreatment working memory function and treatment response to ketamine infusion may confirm that low-dose ketamine infusion is beneficial and should be reserved for patients with TRD.

Risks of Coaggregation of Major Psychiatric Disorders Among First-Degree Relatives of Patients With Bipolar I and Bipolar II Disorder: Evidence From a Nationwide Population-Based Study

Background: Etiologic differences between bipolar I disorder (BD-I) and bipolar II disorder (BD-II) have been challenged recently, and family epidemiologic studies may elucidate the matter. Nevertheless, it remains unclear whether BD-I and BD-II display different familial aggregation patterns within each bipolar disorder subtype and coaggregation with other psychiatric disorders. Method: Per the Taiwan National Health Insurance Research Database (N = 23,258,175), patients with bipolar disorder were classified as having BD-I or BD-II based on the history of psychiatric hospitalization for a manic episode. During the study period (2001-2011), 184,958 first-degree relatives (FDRs) of patients with BD-I and BD-II were identified. By comparing patients with 1:4 age-, sex-, and kinship-matched samples without BD-I/BD-II probands, the relative risks (RRs) of major psychiatric disorders were estimated. Results: FDRs of BD-I probands had a significantly higher risk of BD-I than those of BD-II probands (BD-I proband: RR = 15.80 vs BD-II proband: RR = 5.68, P < .001). The risk of BD-II was similar between FDRs of BD-I and BD-II probands (BD-I proband: RR = 6.48 vs BD-II proband: RR = 5.89, P = .1161). Familial aggregation was greater within each BD subtype than among cross-subtypes. Furthermore, FDRs of BD-I probands had an increased risk of schizophrenia (BD-I probands: RR = 5.83 vs BD-II probands: RR = 2.72, P < .001); FDRs of BD-II probands had a higher likelihood of attention-deficit/hyperactivity disorder (BD-II probands: 2.36 vs BD-I probands: 1.93, P = .0009). Conclusions: The risk of psychiatric disorders is higher among the FDRs of patients with either BD-I or BD-II. Furthermore, the familial specificity of BD-I and BD-II assessed in this study may further the current understanding of etiologic boundaries between bipolar disorder subtypes.

Proton Pump Inhibitors Are Associated with Increased Risk of Psoriasis: A Nationwide Nested Case-Control Study

BACKGROUND

Proton pump inhibitors (PPIs) are among the most widely used drugs. Little is known about the association between PPI use and risk of psoriasis.

OBJECTIVE

To investigate the association between PPI use and subsequent psoriasis risk.

METHODS

We included participants from the Taiwan National Health Insurance Research Database. Patients with PPI use and an incidence of psoriasis (n = 5,756) were assigned to the case cohort and 1:1 matched to controls. PPI use was defined as >30 cumulative defined daily doses (cDDDs); PPI nonuse was defined as ≤30 cDDDs. Logistic regression was used for the analyses.

RESULTS

There was a significant association between PPI use and psoriasis risk. The confounder-adjusted odd ratios (95% confidence interval [CI]) were 1.52 (1.31-1.76) and 1.54 (1.22-1.93) for patients with 120-365 cDDDs and >365 cDDDs, respectively, compared with PPI nonusers. Stratified analyses based on PPI type showed that exposure to lansoprazole (OR, 1.25; 95% CI, 1.11-1.41) was associated with subsequent psoriasis risk.

CONCLUSIONS

PPI use might be associated with an increased risk of developing psoriasis or as an epiphenomenon. Further prospective studies are needed to elucidate the association and underlying mechanisms.

Dengue and dementia risk: A nationwide longitudinal study

BACKGROUND

Accumulating evidence suggests neurological manifestations after dengue infection. However, the relationship between dengue and long-term neurocognitive sequel remains unclear.

METHODS

We recruited 816 patients with dengue and 8,160 controls between 1997 and 2012 using data from Taiwan National Health Insurance Research Database and followed them up until the end of 2013. Individuals who exhibited any type of dementia were identified during the follow-up period. Cox regression analyses were performed with adjustments for demographic data and medical and mental comorbidities (cerebrovascular diseases, traumatic brain injury, hypertension, dyslipidemia, diabetes mellitus, depression, alcohol use disorder, and substance use disorder). The E-value for the causality of the evidence was calculated. Sensitivity analysis was conducted to exclude patients with prodromal dementia.

RESULTS

Patients with dengue were more likely to develop dementia (hazard ratio [HR]: 2.23, 95% confidence interval [CI]: 1.51-3.28), Alzheimer's disease (HR: 3.03, 95% CI: 1.08-8.45), and unspecified dementia (HR: 2.25, 95% CI: 1.43-3.53), but not vascular dementia compared to controls during the follow-up period. Sensitivity analyses after exclusion of the observation period over the first three years or first five years and after exclusion of patients' enrollment before 2010 or 2008 showed consistent findings. The E-values for the HR (range 3.62-5.51) supported the association between dengue and subsequent dementia among the whole population, men, and women.

CONCLUSION

The risk of dementia was 2.23-fold higher in patients diagnosed with dengue during the follow-up period than in the controls. Further studies are necessary to investigate the underlying pathophysiology of dengue and dementia.

Sex-specific autosomal genetic effects across 26 human complex traits

Previous studies have shown that men and women have different genetic architectures across many traits. However, except waist-to-hip ratio (WHR) and waist circumference (WC), it remains unknown whether the genetic effects of a certain trait are weaker or stronger on men/women. With ~18 000 Taiwan Biobank subjects, we comprehensively investigate sexual heterogeneity in autosomal genetic effects, for traits regarding cardiovascular health, diabetes, kidney, liver, anthropometric profiles, blood, etc. 'Gene-by-sex interactions' (G $\times$ S) were detected in 18 out of 26 traits, each with an interaction P-value (${{P}}_{{INT}}$) less than $0.05/104={0.00048}$, where 104 is the number of tests conducted in this study. The most significant evidence of G $\times$ S was found in WHR (${{P}}_{{INT}}$ = 3.2 $\times{{10}}^{-{55}}$) and WC (${{P}}_{{INT}}$ = 2.3$\times{{10}}^{-{41}}$). As a novel G$\times$S investigation for other traits, we here find that the autosomal genetic effects are weaker on women than on men, for low-density lipoprotein cholesterol (LDL-C), uric acid (UA) and diabetes-related traits such as fasting glucose and glycated hemoglobin. For LDL-C and UA, the evidence of G$\times$S is especially notable in subjects aged less than 50 years, where estrogen can play a role in attenuating the autosomal genetic effects of these two traits. Men and women have systematically distinct environmental contexts caused by hormonal milieu and their specific society roles, which may trigger diverse gene expressions despite the same DNA materials. As many environmental exposures are difficult to collect and quantify, sex can serve as a good surrogate for these factors.

Sexually transmitted infections among adolescents with conduct disorder: a nationwide longitudinal study

Studies have demonstrated that conduct disorder is related to risky sexual behaviors, the dominant risk factor for contracting a sexually transmitted infection (STI). However, the association between conduct disorder and STIs remains unclear. Using the Taiwan National Health Insurance Research Database, 5733 adolescents with conduct disorder and 22,932 age- and sex-matched controls without conduct disorder were enrolled from 2001 to 2009 and were subject to follow-up until the end of 2011. Participants who contracted any STI during the follow-up period were identified. Cox regression analysis was performed to examine the likelihood of subsequently contracting an STI for patients and controls. Patients with conduct disorder were more likely than controls to develop any STI (HR 3.95, 95% CI 2.97-5.26) after adjusting for demographic data, psychiatric comorbidities, and use of medications. Long-term use of second-generation antipsychotics (SGAs) was related to a reduced risk (HR 0.36, 95% CI 0.14-0.91) of developing an STI among patients with conduct disorder. Adolescents with conduct disorder had an increased risk of developing any STI later in life compared with those without conduct disorder. Long-term use of SGAs was associated with a lower risk of subsequent STI.

Effect of relative age on childhood mental health: A cohort of 9,548,393 children and adolescents

BACKGROUND

The effect of relative age on the diagnoses of attention deficit hyperactivity disorder (ADHD), disruptive behavior disorder (DD), anxiety disorder, and depressive disorder and the prescription for ADHD and antidepressant medications remains unclear.

AIM

To clarify the impact of relative age in a school year with the diagnoses of ADHD, DD, anxiety disorder, and depressive disorder and the prescription for ADHD and antidepressant medications.

METHODS

The annual cutoff birthdate for entry to school in Taiwan is August 31. The Taiwan National Health Insurance Research Database was used to enroll 9,548,393 children and adolescents aged 3-17 years during the study period (September 1, 2001, to August 31, 2011). The Poisson regression model was performed to examine the likelihood of receiving diagnoses of ADHD, DD, anxiety disorder, and depressive disorder, as well as the prescription of ADHD and antidepressant medications among children born in August (the youngest) and September (the oldest).

RESULTS

Both boys and girls born in August had a higher risk of being diagnosed as having ADHD (odds ratio [OR] = boys: 1.65, girls: 1.80), DD (1.29, 1.45), anxiety disorder (1.49, 1.33), and depressive disorder (1.10, 1.10). Furthermore, children born in August were more likely to be prescribed ADHD medication (1.71, 1.72) and antidepressants (1.18, 1.09) compared with those born in September.

DISCUSSION

Relative age, as an indicator of neurocognitive maturity, is a critical factor for the likelihood of being diagnosed as having ADHD, DD, anxiety disorder, and depressive disorder among children and adolescents.

Postpartum Depression and Psychosis and Subsequent Severe Mental Illnesses in Mothers and Neurodevelopmental Disorders in Children: A Nationwide Study

Background: The association between postpartum depression and postpartum psychosis and subsequent maternal and offspring mental disorders in Western countries has been established; however, whether the relationship can be generalized to the Asian population is unknown. Methods: Using the Taiwan National Health Insurance Research Database, this study enrolled 933,745 mother-infant pairs who delivered their first child and had no history of severe mental illness before childbirth from 2001 to 2010. Postpartum depression and postpartum psychosis were assessed in 3 periods between childbirth and 3, 6, or 12 months after childbirth. Subsequent maternal schizophrenia (ICD-9-CM code: 295), bipolar disorder (ICD-9-CM code: 296 except 296.2x, 296.3x, 296.9x, and 296.82), and depressive disorder (ICD-9-CM codes: 296.2x, 296.3x, 300.4, and 311) and offspring autism spectrum disorder (ASD; ICD-9-CM code: 299) and attention-deficit/hyperactivity disorder (ADHD; ICD-9-CM code: 314) were identified during the follow-up period to the end of 2011. Results: Both postpartum depression and postpartum psychosis were found to be related to increased risks of schizophrenia, bipolar disorder, and depressive disorder in mothers, with hazard ratios (HRs) ranging between 8.80 (95% CI, 7.95-9.74) and 63.96 (95% CI, 50.39-81.18). Children exposed to maternal postpartum depression and psychosis were more likely to develop ADHD. Only postpartum depression was related to the likelihood of offspring ASD. Conclusions: Per these findings, we clinicians and health care providers should closely monitor the mental health condition of postpartum women and their children.

Genome-wide association study in the Taiwan biobank identifies four novel genes for human height: NABP2, RASA2, RNF41 and SLC39A5

Numerous genome-wide association studies (GWASs) have been conducted for the identification of genetic variants involved with human height. The vast majority of these studies, however, have been conducted in populations of European ancestry. Here, we report the first GWAS of adult height in the Taiwan Biobank using a discovery sample of 14 571 individuals and an independent replication sample of 20 506 individuals. From our analysis we generalize to the Taiwanese population genome-wide significant associations with height and 18 previously identified genes in European and non-Taiwanese East Asian populations. We also identify and replicate, at the genome-wide significance level, associated variants for height in four novel genes at two loci that have not previously been reported: RASA2 on chromosome 3 and NABP2, RNF41, and SLC39A5 at 12q13.3 on chromosome 12. RASA2 and RNF41 are strong candidates for having a role in height with copy number and loss of function variants in RASA2 previously found to be associated with short stature disorders, and decreased expression of the RNF41 gene resulting in insulin resistance in skeletal muscle. The results from our analysis of the Taiwan Biobank underscore the potential for the identification of novel genetic discoveries in underrepresented worldwide populations, even for traits, such as height, that have been extensively investigated in large-scale studies of European ancestry populations.

The Risk of Alzheimer's Disease After Acute Appendicitis With or Without Appendectomy

OBJECTIVE

Previous epidemiologic studies have suggested an association between appendectomy and Parkinson's disease. The aim of the current study was to examine the risk of Alzheimer's disease (AD) and other types of dementia following appendicitis or appendectomy for appendicitis.

DESIGN

Population-based cohort study.

SETTING AND PARTICIPANTS

We used claims data from the Taiwan National Health Insurance Research Database. Participants aged ≥45 years with acute appendicitis or who received appendectomy for appendicitis were enrolled and followed up for more than 15 years. Cases and controls underwent 1:1 matching by age, sex, index date, and dementia-related comorbidities.

METHODS

The primary outcome was AD, and secondary outcomes included other dementia types. Adjusted hazard ratios (aHRs) were calculated, and a competing risk regression model was created. The E value for causality of evidence was calculated.

RESULTS

Patients developing appendicitis (0.6% vs 0.1%, P = .005) and those receiving appendectomy for appendicitis (0.4% vs 0.1%, P = .003) had higher incidences of AD than the controls during the follow-up period. A Cox regression analysis with adjustment for potential confounders showed that patients with appendicitis [aHR 6.68, 95% confidence interval (CI) 1.84-24.48] and those receiving appendectomy for appendicitis (aHR 5.01, 95% CI 1.33-18.85) were more likely to develop AD than the controls. These 2 groups also had higher risks for unspecified dementia and all types of dementia but not for vascular dementia than the controls. The age at dementia diagnosis was 88.51 years in the controls; however, among people who developed dementia following appendicitis, the mean age at diagnosis was 70.18 years, and dementia occurred 5.84 years after appendicitis. The competing risk regression models and the E values support the study findings.

CONCLUSIONS AND IMPLICATIONS

After recovery from appendicitis, these patients should be followed up for signs of AD.

Prenatal exposure to acetaminophen increases the risk of atopic dermatitis in children: A nationwide nested case-control study in Taiwan

BACKGROUND

Acetaminophen (APAP) has been associated with the development of atopic diseases. However, little is known about the relationship between prenatal APAP exposure and atopic dermatitis (AD) in offspring.

OBJECTIVE

To investigate the association between prenatal APAP exposure and AD risk in offspring.

METHODS

In this study, 2029 study pairs (AD-affected children and their mothers) and 5,058 control pairs were identified between 1998 and 2008 from the Taiwan Longitudinal Health Insurance Database. Maternal APAP exposure during pregnancy was assessed.

RESULTS

After adjustment for potential confounders, there was a significant association between risk of offspring AD and exposure to acetaminophen in the first trimester (OR 1.16; 95% CI 1.05-1.28), the second trimester (OR 1.14; 95% CI 1.03-1.27), both first and second trimesters (OR 1.30; 95% CI 1.13-1.51), both first and third trimester (OR 1.20; 95% CI 1.04-1.39), any trimester (OR 1.12; 95% CI 1.00-1.26), and all three trimesters (OR 1.32; 95% CI 1.08-1.62) in a dose-response manner.

CONCLUSIONS

Prenatal exposure to acetaminophen was associated with an increased incidence of offspring AD.

Early Pregnancy Risk Among Adolescents With ADHD: A Nationwide Longitudinal Study

Objective: ADHD potentially leads to risky sexual behaviors, and is considered a major risk factor for early pregnancy (EP). However, the association between ADHD and subsequent EP remains unknown. Method: Seven thousand five hundred five adolescents with ADHD and 30,020 age- and sex-matched individuals without ADHD were enrolled from 2001 to 2009 and were followed until the end of 2011. Adolescents who developed any pregnancy (at age ≤30 years) or EP (at age <20 years) during the follow-up period were identified. Results: Adolescents with ADHD were found to be prone to pregnancy (hazard ratio [HR] = 1.27) and EP (HR = 2.30) compared with those without ADHD. Long-term ADHD medication use was related to a lower risk of subsequent any pregnancy (HR = 0.72) and EP (HR = 0.69). Conclusion: Adolescents with ADHD had an increased risk of any pregnancy and EP compared with their non-ADHD counterparts. Long-term ADHD medication use was associated with a lower subsequent EP risk.

Role of appetite hormone dysregulation in the cognitive function among patients with bipolar disorder and major depressive disorder

OBJECTIVES

The association of appetite hormones with cognitive function in patients with affective disorders remains unknown.

METHODS

All total, 58 adult patients with bipolar I disorder, 36 with bipolar II disorder, 40 with major depressive disorder were enrolled and age and sex-matched with 40 controls. The levels of appetite hormones leptin, ghrelin, insulin and adiponectin were assessed. Wisconsin Card Sorting Test was used to assess executive function.

RESULTS

A general linear model, adjusted for demographic data and clinical symptoms, demonstrated the ghrelin levels were higher in patients with bipolar I or II disorder than in those with major depressive disorder and controls (p < 0.001). We also identified a positive correlation of ghrelin level and executive function among patients with bipolar I (p = 0.033) and II (p = 0.027) disorders, but not among those with major depressive disorder and controls.

CONCLUSIONS

Patients with bipolar I or II disorder were more likely to have high levels of ghrelin than patients with major depressive disorder and controls, which may have a positive correlation on the cognitive function of patients with bipolar I or II disorder.

Differential Age Trajectories of White Matter Changes Between Sexes Correlate with Cognitive Performances

Background: Aging is accompanied by a gradual deterioration in multiple cognitive abilities and brain structures. Both cognitive function and white matter (WM) structure are found to be associated with neurodegeneration diseases and correlated with sex during aging. However, it is still unclear whether the brain structural change could be attributable to sex, and how sex would affect cognitive performances during aging. Materials and Methods: Diffusion magnetic resonance imaging (MRI) scans were performed on 1127 healthy participants (age range: 21-89) at a single site. The age trajectories of the WM tract microstructure were delineated to estimate the turning age and changing rate between sexes. The canonical correlation analysis and moderated mediation analysis were used to examine the relationship between sex-linked WM tracts and cognitive performances. Results: The axon intactness and demyelination of sex-linked tracts during aging were multifaceted. Sex-linked tracts in females peak around 5 years later than those in males but change significantly faster after the turning age. Projection and association tracts (e.g., corticospinal tracts and parahippocampal cingulum) contributed to a significant decrease in visuospatial functions (VS) and executive functions (E). We discovered that there is a stronger indirect effect of sex-linked tracts on cognitive functions in females than in males. Conclusion: Our findings suggest that the vulnerable projection and association tracts in females may induce negative impacts on integrating multiple functions, which results in a faster decrease in VS and E.

Prediction of Probable Major Depressive Disorder in the Taiwan Biobank: An Integrated Machine Learning and Genome-Wide Analysis Approach

In light of recent advancements in machine learning, personalized medicine using predictive algorithms serves as an essential paradigmatic methodology. Our goal was to explore an integrated machine learning and genome-wide analysis approach which targets the prediction of probable major depressive disorder (MDD) using 9828 individuals in the Taiwan Biobank. In our analysis, we reported a genome-wide significant association with probable MDD that has not been previously identified: FBN1 on chromosome 15. Furthermore, we pinpointed 17 single nucleotide polymorphisms (SNPs) which show evidence of both associations with probable MDD and potential roles as expression quantitative trait loci (eQTLs). To predict the status of probable MDD, we established prediction models with random undersampling and synthetic minority oversampling using 17 eQTL SNPs and eight clinical variables. We utilized five state-of-the-art models: logistic ridge regression, support vector machine, C4.5 decision tree, LogitBoost, and random forests. Our data revealed that random forests had the highest performance (area under curve = 0.8905 ± 0.0088; repeated 10-fold cross-validation) among the predictive algorithms to infer complex correlations between biomarkers and probable MDD. Our study suggests that an integrated machine learning and genome-wide analysis approach may offer an advantageous method to establish bioinformatics tools for discriminating MDD patients from healthy controls.

Beyond the disconnectivity hypothesis of schizophrenia

To go beyond the disconnectivity hypothesis of schizophrenia, directed (effective) connectivity was measured between 94 brain regions, to provide evidence on the source of the changes in schizophrenia and a mechanistic model. Effective connectivity (EC) was measured in 180 participants with schizophrenia and 208 controls. For the significantly different effective connectivities in schizophrenia, on average the forward (stronger) effective connectivities were smaller, whereas the backward connectivities tended to be larger. Further, higher EC in schizophrenia was found from the precuneus and posterior cingulate cortex (PCC) to areas such as the parahippocampal, hippocampal, temporal, fusiform, and occipital cortices. These are backward effective connectivities and were positively correlated with the positive symptoms of schizophrenia. Lower effective connectivities were found from temporal and other regions and were negatively correlated with the symptoms, especially the negative and general symptoms. Further, a signal variance parameter was increased for areas that included the parahippocampal gyrus and hippocampus, consistent with the hypothesis that hippocampal overactivity is involved in schizophrenia. This investigation goes beyond the disconnectivity hypothesis by drawing attention to differences in schizophrenia between backprojections and forward connections, with the backward connections from the precuneus and PCC implicated in memory stronger in schizophrenia.

Increased Risk of Stroke in Patients With Obsessive-Compulsive Disorder: A Nationwide Longitudinal Study

[Figure: see text].

Obsessive-Compulsive Disorder and Dementia Risk: A Nationwide Longitudinal Study

BACKGROUND

Several case reports have suggested an association between obsessive-compulsive disorder (OCD) and dementia. However, the exact relationship remains unclear.

METHODS

Using the Taiwan National Health Insurance Research Database, 1,347 patients with OCD (ICD-9-CM code 300.3) aged ≥ 45 years and 13,470 controls matched for age, sex, residence, income, and dementia-related comorbidities were included between 1996 and 2013 for investigation of subsequent dementia from enrollment to the end of 2013. Stratified Cox regression analysis on each matched pair was applied to assess the dementia risk between the OCD and control groups. The analysis for the current study was performed in 2018.

RESULTS

Patients with OCD had increased risk of developing any dementia (hazard ratio [HR] = 4.28; 95% confidence interval [CI], 2.96-6.21), Alzheimer's disease (HR = 4.04; 95% CI, 1.55-10.54), and vascular dementia (HR = 3.95; 95% CI, 1.70-9.18) compared with controls.

DISCUSSION

Future research on the pathogenic mechanisms and molecular underpinnings of the relationship between OCD and dementia may lead to the development of novel therapeutics.

Task-Modulated Brain Activity Predicts Antidepressant Responses of Prefrontal Repetitive Transcranial Magnetic Stimulation: A Randomized Sham-Control Study

Background

Prolonged intermittent theta-burst stimulation (piTBS) and repetitive transcranial magnetic stimulation (rTMS) are effective antidepressant interventions for major depressive disorder (MDD). Cognition-modulated frontal theta (frontalθ) activity had been identified to predict the antidepressant response to 10-Hz left prefrontal rTMS. However, whether this marker also predicts that of piTBS needs further investigation.

Methods

The present double-blind randomized trial recruited 105 patients with MDD who showed no response to at least one adequate antidepressant treatment in the current episode. The recruited patients were randomly assigned to one of three groups: group A received piTBS monotherapy; group B received rTMS monotherapy; and group C received sham stimulation. Before a 2-week acute treatment period, electroencephalopgraphy (EEG) and cognition-modulated frontal theta changes (Δfrontalθ) were measured. Depression scores were evaluated at baseline, 1 week, and 2 weeks after the initiation of treatment.

Results

The Δfrontalθ at baseline was significantly correlated with depression score changes at week 1 (r = -0.383, p = 0.025) and at week 2 for rTMS group (r = -0.419, p = 0.014), but not for the piTBS and sham groups. The area under the receiver operating characteristic curve for Δfrontalθ was 0.800 for the rTMS group (p = 0.003) and was 0.549 for the piTBS group (p = 0.619).

Conclusion

The predictive value of higher baseline Δfrontalθ for antidepressant efficacy for rTMS not only replicates previous results but also implies that the antidepressant responses to rTMS could be predicted reliably at baseline and both piTBS and rTMS could be effective through different neurobiological mechanisms.

Factors Affecting Delayed Initiation and Continuation of Medication Use for Attention-Deficit/Hyperactivity Disorder: A Nationwide Study

Objective: This study evaluated the predictors for delayed initiation and continuation of ADHD medication use in children and adolescents with ADHD in Taiwan. Methods: This longitudinal cohort study enrolled 188,061 children and adolescents with ADHD between 2001 and 2011. Delayed initiation of ADHD medications was defined as the interval >365 days between diagnosis and first prescription, and continuation of ADHD medications was defined as ≥365 defined daily doses of ADHD medications. Results: Of the included patients, 39.2% were never treated with ADHD medications. Delayed initiation and continuation of ADHD medication use were found in 11.9% and 19.9% of the ever-treated patients, respectively. Younger age at ADHD diagnosis, male sex, older mother's age at child's ADHD diagnosis, and higher family income were associated with more delayed initiation but were also associated with more continuation of ADHD medication use. Conclusions: The initiation and continuation of ADHD medication use might be underlined by different mechanisms and warrant different strategies.

The Risk of Epilepsy after Long-term Proton Pump Inhibitor Therapy

BACKGROUND

Prescription-event monitoring studies have reported incident epilepsy or seizures in proton pump inhibitor (PPI) recipients. We examined the risk of epilepsy after prolonged PPI exposure and determine what age group was at higher risk of epilepsy.

METHODS

We performed a case-control study nested within a sample of Taiwan National Health Insurance beneficiaries (n = 1,000,000). PPI users with subsequent epilepsy were selected as the case cohort. Controls were PPI users without subsequent epilepsy, matched for age, sex, PPI use indication, enrollment time, end point time, follow-up period, overall systemic health, and comorbidities. The total dose of PPI was defined as the cumulative defined daily dose (cDDD). Prolonged PPI use was defined as a cDDD > 365. A logistic regression analysis was performed. Population attributable risk was calculated.

RESULTS

Epilepsy occurred 4.13 years after the initiation of PPI use. PPI users with the highest risk of incident epilepsy received a cDDD > 365 [odds ratio = 1.63, 95% confidence interval = 1.37-1.95], followed by 121-365 cDDD (1.33, 1.18-1.51) and 31-120 cDDD (1.15, 1.02-1.29), compared to those receiving a cDDD ≤ 30, after adjusting for potential confounders. Prolonged PPI use increased the risk of epilepsy in all age groups, and the risk was highest for those older than 80 years (3.11, 1.67-5.79). The population attributable risk was 12.2% (> 365 cDDD vs ≤ 30 cDDD).

DISCUSSION

Prolonged PPI therapy was associated with an increased risk of epilepsy, particularly in the elderly population.

Efficacy and tolerability of theta-burst stimulation for major depression: A systematic review and meta-analysis

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is the current treatment option for major depression (MD). Theta-burst stimulation (TBS), a variation of rTMS, affords a short stimulation duration, low stimulation pulse intensity, and possibility to improve rTMS efficiency. This systematic review and meta-analysis examined the studies on efficacy and tolerability of TBS in patients with MD.

METHODS

This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched the literature from 1990 until May 24, 2020, and performed a random-effects meta-analysis by including response and remission rates of depression and dropout rates as main outcome measures.

RESULTS

In total, 10 studies including 6 randomized controlled trials (RCTs; n = 294) and 4 uncontrolled clinical trials (non-RCTs; n = 297) were included. The overall effect size of response rate and remission rates were 0.38 (95% confidence interval [CI]: 0.29-0.48) and 0.20 (95% CI: 0.13-0.29), respectively. Notably, the TBS group showed favorable efficacy without major adverse events.

CONCLUSIONS

TBS treatment was more efficient in terms of time and energy than the standard rTMS was. Our meta-analysis provided evidence that the application of TBS to the dorsolateral prefrontal cortex is associated with significant antidepressant effects along with favorable tolerability.

Role of interleukin 8 in depression and other psychiatric disorders

Low grade neuroinflammation has been suggested as one of the underlying mechanisms of many psychiatric diseases as well as cognitive disorders. Interleukin 8 (IL-8), a proinflammatory cytokine produced by many cell types including macrophage and microglia, mainly functions as a neutrophil chemoattractant in the bloodstream. IL-8 is also found in the brain, where it is released from microglia in response to proinflammatory stimuli. In this review, we highlight studies focusing on the role of IL-8 in psychiatric diseases such as major depression, bipolar disorder, schizophrenia, sleep disorder, autism spectrum disorder, anxiety disorders and dementia. Increased peripheral IL-8 levels have been reported in these diseases, particularly in schizophrenic disorder, bipolar disorder, obstructive sleep apnea and autism spectrum disorder. The literature on IL-8 and major depression is inconsistent. IL-8 has been found to be a factor associated with schizophrenic prognosis and therapeutic response, and may affect a wide range of symptomatology. Considering that the exact role of immune alterations is still under research, the success of immune-based therapies in psychiatric diseases is limited for the time being.

Association between gastrointestinal symptoms and depression among older adults in Taiwan: A cross-sectional study

BACKGROUND

Older adults with depression more frequently experience somatic and gastrointestinal (GI) problems compared with people without depression and younger adults with depression. However, whether GI symptoms are predictive of elevated rates of depression among older adults is unclear.

METHODS

We enrolled 106 older adults (>60 years old); 69 had late-life depression (LLD), and 37 were controls. All participants gave ratings on the Gastrointestinal Symptom Rating Scale (GSRS) and Hamilton Depression Rating Scale. Food consumption was assessed using a food frequency questionnaire, and a Mediterranean diet score was used as a covariate.

RESULTS

Compared with the controls, patients with LLD reported higher levels of depressive and GI symptoms and reported more reflux, abdominal pain, and dyspepsia symptoms, and these symptoms were correlated with Hamilton Depression Rating Scale scores (GSRS total: β = 0.47; reflux: β = 1.47; abdominal pain: β = 1.98; dyspepsia: β = 1.02; all p < 0.01). After demographic variables and Mediterranean diet score were controlled for, a logistic regression analysis indicated that total GSRS score was an independent determinant of LLD (odds ratio: 1.20, 95% CI: 1.04-1.38). Moreover, a stratified analysis by depression severity indicated that higher total GSRS score may contribute to greater depression severity (odds ratio: 1.25, 95% CI: 1.04-1.52).

CONCLUSION

We provide evidence that GI symptoms are associated with depressive symptoms among patients with LLD. Older people with more specific GI symptoms, such as reflux, abdominal pain, and dyspepsia, are potentially at greater risk of having LLD.

Interest-activity symptom severity predicts response to ketamine infusion in treatment-resistant depression

BACKGROUND

Interest and activity are part of the positive mood domain. Evidence suggests the symptom domain of interest-activity at baseline as a clinical predictor for treatment response to traditional antidepressants. However, whether this domain is related to the response to a single low-dose ketamine infusion remains unclear.

METHODS

Seventy-one patients with treatment-resistant depression were randomized to 3 treatment groups: a single 0.5 or 0.2 mg/kg ketamine or normal saline placebo infusion. Depressive symptoms were measured using the 17-item Hamilton Depression Rating Scale before infusions and at postinfusion period (at 40 min and up to 2 weeks). Low (mild) versus medium versus high (severe) interest-activity symptom domain groups were classified on the basis of the cutoff point of ± 0.4 standard deviation. The effect of baseline interest-activity symptoms on outcomes was tested using generalized estimating equation models.

RESULTS

The interest-activity symptom domain as a continuous variable (β = 8.413, p = .016) was related to the trajectory of depressive symptoms. Stratified by levels of the interest-activity symptom domain, in the low interest-activity, 0.2 mg/kg ketamine infusion (β = 0.013) demonstrated the greatest antidepressant effect (p < .01) compared with 0.5 mg/kg ketamine (β = 0.739) and placebo infusions; however, in the high interest-activity, 0.5 mg/kg ketamine infusion (β = 0.001) demonstrated the best antidepressant effect (p < .01) compared with 0.2 mg/kg ketamine (β = 1.372) and placebo infusions.

DISCUSSION

The symptom domain of interest-activity was an independent predictor for the treatment response to a single low-dose ketamine infusion.

Familial coaggregation of major psychiatric disorders among first-degree relatives of patients with obsessive-compulsive disorder: a nationwide study

BACKGROUND

Whether the first-degree relatives (FDRs) of patients with obsessive-compulsive disorder (OCD) have an increased risk of the major psychiatric disorders, namely schizophrenia, bipolar disorder, OCD, major depressive disorder (MDD), autism spectrum disorder (ASD), and attention deficit hyperactivity disorder (ADHD), remains unclear.

METHODS

Using the Taiwan National Health Insurance Research Database with the whole population sample size (n = 23 258 175), 89 500 FDRs, including parents, offspring, siblings, and twins, of patients with OCD were identified in our study. The relative risks (RRs) of major psychiatric disorders were assessed among FDRs of patients with OCD.

RESULTS

FDRs of patients with OCD had higher RRs of major psychiatric disorders, namely OCD (RR 8.11, 95% confidence interval (CI) 7.68-8.57), bipolar disorder (RR 2.85, 95% CI 2.68-3.04), MDD (RR 2.67, 95% CI 2.58-2.76), ASD (RR 2.38, 95% CI 2.10-2.71), ADHD (RR 2.19, 95% CI 2.07-2.32), and schizophrenia (RR 1.97, 95% CI 1.86-2.09), compared with the total population. Different familial kinships of FDRs, such as parents, offspring, siblings, and twins consistently had increased risks for these disorders. In addition, a dose-dependent relationship was found between the numbers of OCD probands and the risk of each major psychiatric disorder.

CONCLUSIONS

The FDRs, including parents, offspring, siblings, and twins, of patients with OCD have a higher risk of OCD, schizophrenia, bipolar disorder, MDD, ADHD, and ASD. The familial co-aggregation of OCD with OCD and other major psychiatric disorders was existent in a dose-dependent manner. Given the increased risks of psychiatric disorders, medical practitioners should closely monitor the mental health of the FDRs of patients with OCD.

Proton Pump Inhibitor Exposure and Acute Myocardial Infarction Risk: A Nested Cohort Study

BACKGROUND

Association of proton pump inhibitor (PPI) exposure with acute myocardial infarction (AMI) risk in the Caucasian population remains under debate. Here, we clarified whether PPI exposure might be related to an increased new-onset AMI risk in an Asian population.

METHOD

Data of 27,624 patients with PPI exposure followed by new-onset AMI development were extracted from Taiwan National Health Insurance Research Database and age- and sex-matched with 27,624 controls with PPIs exposure, but without subsequent AMI and ischemic heart disease development. The amount of PPI exposure was calculated based on the cumulative defined daily dose (cDDD) during the follow-up period. Subsequent AMI risk was measured after adjustments of demographic data and indication of PPI use.

RESULTS

AMI risk increased with an increase in PPI exposure: with cDDD ≤ 30 as the reference, the odds ratios (95% confidence intervals) for cDDDs of > 365 was 1.56 (1.45-1.69). All five PPI categories, including pantoprazole, lansoprazole, omeprazole, esomeprazole, and rabeprazole, increased AMI risk.

CONCLUSIONS

Our study demonstrated long-term or high-dose PPI exposure associated with increased new-onset AMI risk in patients without a history of any ischemic heart disease. The underlying mechanisms of PPI-related cardiovascular effects deserve more investigation.

Group Music Intervention Using Percussion Instruments to Reduce Anxiety Among Elderly Male Veterans with Alzheimer Disease

Background

This study aimed to assess the impact of a group music intervention on anxiety and depression of elderly male veterans with dementia.

Material/Methods

In total, 50 elderly men with Alzheimer disease were randomly divided into intervention and control groups. Patients in the intervention group attended a 60-minute group music session that used percussion instruments with familiar music in the morning once a week for 12 weeks, whereas those in the control group received a rest and reading session at the same intervals and under the same conditions. The Hamilton Anxiety Rating Scale and Geriatric Depression Scale were used to assess anxiety and depression at baseline, week 6, and week 12. The Primary Measures of Music Audiation (PMMA) was used to assess musical aptitude at the baseline.

Results

A significant reduction in the anxiety level following the 12-week music sessions was observed in the intervention group (P<.001), but there was no significant change in the control group. However, the change in depressive symptoms between the 2 groups was nonsignificant. In the intervention group, when stratifying patients based on music aptitude determined through PMMA assessment, patients with high PMMA scores had significantly reduced anxiety symptoms over time compared with those with low scores.

Conclusions

For elderly male veterans with dementia, participating in a group music intervention reduced anxiety symptoms. In patients with high musical aptitude, the treatment effects on anxiety reduction were satisfactory. Measures of music aptitude may provide valuable information regarding patients’ response to music intervention.

Proinflammatory Cytokine Dysregulation and Cognitive Dysfunction Among Patients with Remitted Bipolar I and II Disorders

BACKGROUND

Euthymic patients with bipolar disorder reportedly demonstrated increased levels of proinflammatory cytokines and cognitive function deficits. Because uncertain differences exist in cognitive function and proinflammatory cytokines between remitted bipolar I (BD1) and bipolar II (BD2) disorders, we performed this study to further investigate these differences.

METHOD

We enrolled 58 patients with remitted BD1 and 27 with remitted BD2, and matched them for age and sex with 51 controls. Proinflammatory cytokines, including soluble interleukin-6 receptor (sIL-6R), C-reactive protein, and soluble tumor necrosis factor receptor 1 (sTNFR1) were measured, and performance in the Word List Memory Task (WLMT) and Wisconsin Card Sorting Task (WCST) was assessed.

RESULTS

Significantly elevated levels of sTNFR1 were observed among patients with BD1 (p < .001) and BD2 (p = .038) compared with the controls; however, they did not differ between patients with BD1 and BD2 (p =.130). Working memory deficit measured by the WLMT was significantly greater in patients with BD1 (p < .001) and BD2 (p < .05) compared with controls, but did not differ between patients with BD1 and BD2 (p > 0.1). Furthermore, sTNFR1 levels were negatively correlated with cognitive function measured using the WLMT and WCST (all p < .05).

DISCUSSION

Our results showed that euthymic patients with BD1 and BD2 showed similar levels of sTNFR1 and cognitive function (especially working memory) impairments. Further investigation is required to explore whether a common pathophysiology may contribute to the shared inflammatory and cognitive alterations between BD1 and BD2.

Remission of depression is associated with asymmetric hemispheric variation in EEG complexity before antidepressant treatment

BACKGROUND

Intense increased alpha activity in the anterior brain has been recognized as one of the biomarkers of depression. This study aimed to explore whether complexity measures of electroencephalogram (EEG) signals vary across the frontal region between patients with or without remission in depression.

METHODS

Ninety-four patients with moderate-to-severe major depression underwent the experiment. Hilbert-Huang transform was applied to extract individual alpha EEG instantaneous amplitude. Averaged regional complexity (SampEn_Mean) on frontal and frontal-central areas as well as bilateral frontal areas were assessed according to multiscale entropy between the remitters (n = 26/94, 27.66%) and poor responders (n = 29/94, 30.85%). Standard deviation of regional complexity (SampEn_SD) was used as a parameter to test the homogeneity of frontal alpha complexity.

RESULTS

No significant differences in SampEn_Mean for the frontal or frontal-central area were observed between the remitters and poor responders. However, the SampEn_SD (i.e., regional homogeneity of frontal alpha complexity) significantly increased in the frontal-central area after treatment among the poor responders in comparison to their baseline, whereas the remitters showed an opposite trend. The remitters further showed significantly larger SampEn_SD on the left frontal area at baseline, and this lateralization disappeared after antidepressant treatment except for the poor responders.

LIMITATIONS

This study was limited by a small sample size and without healthy controls.

CONCLUSIONS

Homogeneity in frontal-central alpha complexity and interhemispheric asymmetry normalization of anterior EEG complexity are associated with antidepressant efficacy, suggesting that homogeneity of dynamical brain activity is a key linked to the successful treatment of major depression.

Using classification and regression tree modelling to investigate treatment response to a single low-dose ketamine infusion: Post hoc pooled analyses of randomized placebo-controlled and open-label trials

BACKGROUND

Evidence suggests that clinical markers, such as comorbid anxiety, body weight, and others can assist in predicting response to low-dose ketamine infusion in treatment resistant depression patients. However, whether a composite of clinical markers may improve the predicted probability of response is uncertain.

METHODS

The current study investigated the results of our previous randomized placebo-controlled and open-label trials in which 73 patients with treatment-resistant depression (TRD) received a single ketamine infusion of 0.5 mg/kg. Clinical characteristics at baseline, including depression severity, duration of the current episode, obesity, comorbidity of anxiety disorder, and current suicide risk, were assessed as potential predictors in a classification and regression tree model for treatment response to ketamine infusion.

RESULTS

The predicted probability of a composite of age at disease onset, depression severity, duration of current episode, and obesity/overweight was significantly greater (area under curve = .736, p = .001) than that of any one marker (all p > .05). The most powerful predictors of treatment response to ketamine infusion were younger age at disease onset and obesity/overweight. The strongest predictors of treatment nonresponse were longer duration of the current episode and greater depression severity at baseline.

DISCUSSION

Depression severity, duration of the current episode, obesity, and age at disease onset may predict treatment response versus nonresponse to low-dose ketamine infusion. However, whether our predicted probability for a single infusion may be applied to repeated infusions would require further investigation.

CLINICAL TRIAL REGISTRATION

UMIN Clinical Trials Registry (UMIN000023581 and UMIN000016985).

Using classification and regression tree modeling to investigate appetite hormones and proinflammatory cytokines as biomarkers to differentiate bipolar I depression from major depressive disorder

BACKGROUND

Altered immunity and metabolic profiles have been compared between bipolar depression (BD) and major depressive disorder (MDD). This study aimed at developing a composite predictor of appetite hormones and proinflammatory cytokines to differentiate BD from MDD.

METHODS

This cross-sectional study enrolled patients with BD and those with MDD aged 20 to 59 years and displaying depressive episodes. Clinical characteristics (age, sex, body mass index, and depression severity), cytokines (C-reactive protein, interleukin [IL]-2, IL-6, tumor necrosis factor [TNF]-α, P-selectin, and monocyte chemoattractant protein), and appetite hormones (leptin, adiponectin, ghrelin, and insulin) were assessed as potential predictors using a classification and regression tree (CRT) model for differentiating BD from MDD.

RESULTS

The predicted probability of a composite predictor of ghrelin and TNF-α was significantly greater (for BD: area under curve = 0.877; for MDD: area under curve = 0.914) than that of any one marker (all P > .05) to distinguish BD from MDD. The most powerful predictors for diagnosing BD were high ghrelin and TNF-α levels, whereas those for MDD were low ghrelin and TNF-α levels.

CONCLUSION

A composite predictor of ghrelin and TNF-α driven by CRT could assist in the differential diagnosis of BD from MDD with high specificity. Further clinical studies are warranted to validate our results and to explore underlying mechanisms.

Differential Patterns of Gyral and Sulcal Morphological Changes During Normal Aging Process

The cerebral cortex is a highly convoluted structure with distinct morphologic features, namely the gyri and sulci, which are associated with the functional segregation or integration in the human brain. During the lifespan, the brain atrophy that is accompanied by cognitive decline is a well-accepted aging phenotype. However, the detailed patterns of cortical folding change during aging, especially the changing age-dependencies of gyri and sulci, which is essential to brain functioning, remain unclear. In this study, we investigated the morphology of the gyral and sulcal regions from pial and white matter surfaces using MR imaging data of 417 healthy participants across adulthood to old age (21–92 years). To elucidate the age-related changes in the cortical pattern, we fitted cortical thickness and intrinsic curvature of gyri and sulci using the quadratic model to evaluate their age-dependencies during normal aging. Our findings show that comparing to gyri, the sulcal thinning is the most prominent pattern during the aging process, and the gyrification of pial and white matter surfaces were also affected differently, which implies the vulnerability of functional segregation during aging. Taken together, we propose a morphological model of aging that may provide a framework for understanding the mechanisms underlying gray matter degeneration.

Gene-Based Association Analysis Suggests Association of HTR2A With Antidepressant Treatment Response in Depressed Patients

The serotonin [5-hydroxytryptamine (5-HT)] system has been implicated in the pathogenesis of major depressive disorder (MDD). Among the 5-HT receptor subtypes, 5-HT2 is one of the major pharmacological therapeutic targets for MDD. There have been inconsistent findings in previous pharmacogenetic studies investigating the antidepressant therapeutic response using one or several 5-HT2A (HTR2A) genetic polymorphisms. By using gene-based association analysis, we hope to identify genetic variants of HTR2A which are related to MDD susceptibility and its antidepressant therapeutic response. 288 HTR2A single nucleotide polymorphisms in MDD susceptibility have been investigated through a case–control (455 MDD patients and 2, 998 healthy controls) study, as well as in antidepressant efficacy (n = 455) in our current research. The 21-item Hamilton Rating Scale for Depression was used to evaluate measures of antidepressant therapeutic efficacy. From two MDD groups in the antidepressant therapeutic response, by using gene-based analyses, we have identified 14 polymorphisms as suggestive markers for therapeutic response (13 for remission and 1 for response) in both meta- and mega-analyses. All of these HTR2A reported polymorphisms did not reach statistical significance in the case–control association study. This current investigation supported the link between HTR2A variants and antidepressant therapeutic response in MDD but not with MDD susceptibility.

Network-Specific Corticothalamic Dysconnection in Attention-Deficit Hyperactivity Disorder

BACKGROUND

Functional connectivity (FC) is believed to be abnormal in attention-deficit hyperactivity disorder (ADHD). Most studies have focused on frontostriatal systems, and the role of the thalamic network in ADHD remains unclear. The current study used FC magnetic resonance imaging (fcMRI) to explore corticothalamic network properties and correlated network dysconnection with ADHD symptom severity.

METHODS

Eighteen adolescents with ADHD and 16 healthy controls aged 12 to 17 years underwent resting functional MRI scans, clinical evaluations, and 2 parent rating scales, namely the Swanson, Nolan, and Pelham IV scale and the Child Behavior Checklist. Six a priori cortical regions of interest were used to derive 6 networks: the dorsal default mode network, frontoparietal network, cingulo-opercular network (CON), primary sensorimotor network (SM1), primary auditory network, and primary visual network (V1). The corticothalamic connectivity for each network was calculated for each participant and then compared between the groups. We also compared the 2 scales with the network connectivity.

RESULTS

The corticothalamic connectivity within the CON was significantly reduced (p < 0.05) among adolescents with ADHD compared with the controls. The corticothalamic dysconnection within the CON, SM1, and V1 networks negatively correlated with ADHD symptom severity.

CONCLUSION

This network analysis indicates that corticothalamic dysconnection in ADHD involves the CON, SM1, and V1 networks and relates to symptom severity. The findings provide evidence of dysfunctional thalamus-related networks in ADHD.