Hai-Gwo Hwu

Prevalence of suicide ideation and suicide attempts in nine countries

BACKGROUND There are few cross-national comparisons of the rates of suicide ideation and attempts across diverse countries. Nine independently conducted epidemiological surveys using similar diagnostic assessment and criteria provided an opportunity to obtain that data. METHODS Suicide ideation and attempts were assessed on the Diagnostic Interview Schedule in over 40000 subjects drawn from the United States, Canada, Puerto Rico, France, West Germany, Lebanon, Taiwan, Korea and New Zealand. RESULTS The lifetime prevalence rates/100 for suicide ideation ranged from 2.09 (Beirut) to 18.51 (Christchurch, New Zealand). Lifetime prevalence rates/100 for suicide attempts ranged from 0.72 (Beirut) to 5.93 (Puerto Rico). Females as compared to males had only marginally higher rates of suicidal ideation in most countries, reaching a two-fold increase in Taiwan. Females as compared to males had more consistently higher rates for suicide attempts, reaching a two- to three-fold increase in most countries. Suicide ideation and attempts in most countries were associated with being currently divorced/separated as compared to currently married. CONCLUSIONS While the rates of suicide ideation varied widely by country, the rates of suicide attempts were more consistent across most countries. The variations were only partly explained by variation in rates of psychiatric disorders, divorce or separation among countries and are probably due to cultural features that we do not, as yet, understand.

Prevalence of psychiatric disorders in Taiwan defined by the Chinese Diagnostic Interview Schedule

ABSTRACT The Taiwan Psychiatric Epidemiological Project, conducted from 1982 to 1986, used the multistage random sampling method with 5005, 3004 and 2995 subjects selected respectively from metropolitan Taipei (MT), 2 small towns (ST) and 6 rural villages (RV). The case identification tool was the Chinese modified Diagnostic Interview Schedule (DIS‐CM). This study presents the lifetime and one‐year prevalence of 27 and of 17 specific psychiatric disorders respectively. The lifetime prevalence of any disorder defined by the DIS‐CM—excluding tobacco dependence—was 16.3%, 28.0% and 21.5% in the MT, ST and RV samples respectively. The differences in lifetime prevalence between the sexes and between the 3 sampling areas were significant for 15 and 8 disorders respectively. The ST sample seemed to have the most disorders, with the highest prevalence among 3 sampling areas. The mean ratio of one‐year to lifetime prevalence was 0.67. The differences in prevalence rates between the 3 sampling areas and between the international studies are discussed from methodological, social and cultural points of view.

Frequency-specific alternations in the amplitude of low-frequency fluctuations in schizophrenia

Schizophrenia has been associated with abnormal task‐related brain activation in sensory and motor regions as well as social cognition network. Recently, two studies investigated temporal correlation between resting‐state functional magnetic resonance imaging (R‐fMRI) low‐frequency oscillations (LFOs) in schizophrenia but reported mixed results. This may be due to the different frequency bands used in these studies. Here we utilized R‐fMRI to measure the amplitude of low‐frequency fluctuations (ALFF) and fractional ALFF (fALFF) in three different frequency bands (slow‐5: 0.01–0.027 Hz; slow‐4: 0.027–0.08 Hz; and typical band: 0.01–0.08 Hz) in 69 patients with schizophrenia and 62 healthy controls. We showed that there were significant differences in ALFF/fALFF between the two bands (slow‐5 and slow‐4) in regions including basal ganglia, midbrain, and ventromedial prefrontal cortex. Importantly, we also identified significant interaction between frequency bands and groups in inferior occipital gyrus, precunus, and thalamus. The results suggest that the abnormalities of LFOs in schizophrenia is dependent on the frequency band and suggest that future studies should take the different frequency bands into account when measure intrinsic brain activity. Hum Brain Mapp 35:627–637, 2014.

Prevalence and Determinants of Workplace Violence of Health Care Workers in a Psychiatric Hospital in Taiwan

Prevalence and Determinants of Workplace Violence of Health Care Workers in a Psychiatric Hospital in Taiwan: Wen‐Ching Chen, et al. Yu‐Li Hospital, Department of Health, Executive Yuan, Taiwan—Workplace violence, a possible cause of job stress, has recently become an important concern in occupational health. This study determined the prevalence of workplace violence and its risk factors for employees at a psychiatric hospital in Taiwan. A questionnaire developed by ILO/ICN/WHO/PSI was first translated and validated. It was then used to survey the prevalence of workplace violence in the last 12 months experienced by all nursing aides, nurses, and clerks at the hospital. Multiple logistic regression models were constructed to discover the determinants of violence. A total of 222 out of 231 surveyed workers completed a valid questionnaire. The one‐year prevalence rates of physical violence (PV), verbal abuse, bullying/mobbing, sexual harassment, and racial harassment were 35.1, 50.9, 15.8, 9.5, and 4.5%, respectively. The prevalence of PV at this hospital was higher than that reported by other countries for the health sector. A high anxiety level was associated with the occurrence of PV. These results need to be corroborated by future investigation. A training program may be required for high risk groups to reduce workplace violence.

Suggestive evidence for linkage of schizophrenia to markers on chromosome 13 in Caucasian but not Oriental populations

Abstract Previously we reported suggestive evidence for linkage of schizophrenia to markers on chromosome 13q14.1–q32. We have now studied an additional independent sample of 44 pedigrees consisting of 34 Taiwanese, 9 English and 1 Welsh family in an attempt to replicate this finding. Narrow and broad models based on Research Diagnostic Criteria or the Diagnostic and Statistical Manual of Mental Disorders, third edition, revised, were used to define the schizophrenia phenotype. Under a dominant genetic model, two-point lod scores obtained for most of the markers were negative except that marker D13S122 gave a total lod score of 1.06 (θ = 0.2, broad model). As combining pedigrees from different ethnic origins may be inappropriate, we combined this replication sample and our original sample, and then divided the total sample into Caucasian (English and Welsh pedigrees) and Oriental (Taiwanese and Japanese pedigrees) groups. The Caucasian pedigrees produced maximized admixture two-point lod scores (A-lod) of 1.41 for the marker D13S119 (θ = 0.2, α = 1.0) and 1.54 for D13S128 (θ = 0, α = 0.3) with nearby markers also producing positive A-lod scores. When five-point model-free linkage analysis was applied to the Caucasian sample, a maximum lod score of 2.58 was obtained around the markers D13S122 and D13S128, which are located on chromosome 13q32. The linkage results for the Oriental group were less positive than the Caucasian group. Our results again suggest that there is a potential susceptibility locus for schizophrenia on chromosome 13q14.1–q32, especially in the Caucasian population.

Dopamine D4 receptor gene polymorphisms and neuroleptic response in schizophrenia

BACKGROUND Dopamine D4 receptor (DRD4) gene polymorphisms are associated with various pharmacologic activities. This study investigated whether polymorphisms of 48-bp tandem repeats in the exon 3 of the DRD4 gene are related to neuroleptic response. METHODS The neuroleptic response at the acute stage of schizophrenia was assessed in 80 (48 men, 32 women) schizophrenic patients. The negative symptoms at remission were also rated. DRD4 genotype was established using the polymerase chain reaction. Patients with genotypes containing an allele with only two repeats (2-2, 2-3, 2-4, 2-6) were assigned to group I (n = 38). Those homozygous for four 48-bp repeats were assigned to group II (n = 42). RESULTS Thirteen (34.2%) of the 38 group I subjects and 26 (61.9%) of the 42 group II subjects had good neuroleptic response during acute stage treatment (chi 2 6.12, df = 1, p < .02). In remission, the rates of negative symptoms of blunt affect, avolition, and global negative rating were higher in group I than in group II. This was more prominent in men than in women. CONCLUSIONS The presence of homozygous four 48-bp repeats in both alleles in exon 3 of the DRD4 gene is associated with good neuroleptic response during acute treatment, and with a lower prevalence of negative symptoms at remission, especially in male schizophrenic patients.

A single nucleotide polymorphism fine mapping study of chromosome 1q42.1 reveals the vulnerability genes for schizophrenia, GNPAT and DISC1 : Association with impairment of sustained attention

BACKGROUND The marker D1S251 of chromosome 1q42.1 showed significant association with schizophrenia in a Taiwanese sample. We used single nucleotide polymorphism (SNP) fine mapping to search for the vulnerability genes of schizophrenia. METHODS We selected 120 SNPs covering 1 Mb around D1S251 from the public database. These selected SNPs were initially validated if allele frequency was >10%. Forty-seven validated SNPs were genotyped in 102 families with at least 2 siblings affected with schizophrenia. RESULTS Two SNP blocks showed significant association with schizophrenia. Block 1 (five-SNP), located between intron 2 and intron 13 of the glyceronephosphate O-acyltransferase (GNPAT) gene, showed the most significant associations using single-locus TDT (z = -2.07, p = .038, df = 1) and haplotype association analyses (z = -1.99, p = .046, df = 1). Block 2 (two-SNP), located between intron 4 and intron 5 of the disrupted-in-schizophrenia 1 (DISC1) gene, also showed the most significant results in both the single-locus (z = -3.22, p = .0013, df = 1) and haplotype association analyses (z = 3.35, p = .0008, df = 1). The association of the DISC1 gene with schizophrenia was mainly in the patient group with sustained attention deficits as assessed by the Continuous Performance Test. CONCLUSIONS Chromosome 1q42.1 harbors GNPAT and DISC1 as candidate genes for schizophrenia, and DISC1 is associated with sustained attention deficits.

No association of G72 and d-amino acid oxidase genes with schizophrenia

The genes of D-amino acid oxidase (DAAO) activator (DAOA or G72; 13q34) and DAAO (12q24) have been suggested as candidate genes and involved in the N-methyl-D-aspartate receptor regulation pathway for schizophrenia. In order to evaluate the potential association of these two genes with schizophrenia in a Taiwanese sample, three single nucleotide polymorphisms (SNPs) for DAAO (rs2111902, rs3918346, rs3741775) and eleven SNPs for G72 (rs3916965, rs3916966, rs3916967, rs2391191, rs3916968, rs947267, rs778294, rs3916970, rs3916971, rs778293, rs3918342) were genotyped by the MALDI-TOF mass spectrometry method in 218 families (864 individuals) containing at least two siblings affected with schizophrenia. In SNP-based single locus association analyses, neither G72 nor DAAO showed significant association with schizophrenia. Additionally, a three-SNP haplotype in DAAO, and a four-SNP as well as a two-SNP haplotype in G72, showed no significant associations with schizophrenia. These results suggest that the DAAO and G72 genes are not susceptibility genes for schizophrenia in a Taiwanese sample.

Neuregulin 1 gene and variations in perceptual aberration of schizotypal personality in adolescents

BACKGROUND We test the hypothesis that the neuregulin 1 (NRG1 ) gene at chromosome 8p22-p12, which has been implicated as a susceptibility gene to schizophrenia, is associated with variations in schizotypal personality in non-clinical populations. METHOD A randomly selected sample of 905 adolescents were assessed for their personality features using the Perceptual Aberration Scale (PAS) and the Schizotypal Personality Questionnaire (SPQ) and genotyped for three single nucleotide polymorphisms (SNP8NRG221533, rs3924999, and rs2954041) at the NRG1 gene. Relations between the three genetic variants and continuous schizotypal personality scores were evaluated using ANOVA for single-locus analyses and haplotype trend regression test for multi-locus analyses. RESULTS Single locus analysis showed that the A allele of rs3924999, a functional polymorphism in exon 2, had the largest effect size and exhibited a prominent allele-dose trend effect for the PAS score. Haplotype analyses using the haplotype trend regression test indicated that the A allele of rs3924999 was mainly responsible for the association with the PAS but not with the SPQ or its three factors, and the magnitude of significance was not strengthened by the combination of this allele with adjacent locus. CONCLUSIONS Our study provides the first evidence for the association of NRG1 with schizotypal personality and indicates a possible role of NRG1 in the genetic etiology of schizophrenia through perceptual aberrations.

Memory impairment and auditory evoked potential gating deficit in schizophrenia

Impaired sensory gating and memory function were reported in a study of 10 schizophrenic patients and 10 age- and sex-matched normal subjects. The P50 component of the auditory evoked potential was used as an index of gating. Explicit memory was tested with the Wechsler Memory Scale and implicit memory by artificial grammar learning. The schizophrenic patients showed deficits in both verbal paired associate and visual reproduction tasks. They demonstrated impaired implicit learning in color patterns but not letter strings. They also showed impaired P50 sensory gating. Three-dimensional brain mapping revealed a differential distribution of brain potentials in the processing of S1 and S2 at either P50 or N100 in both groups. However, the group difference was not statistically confirmed. In the controls, both implicit letter-string learning and explicit verbal paired associates were positively correlated with N100 gating, suggesting an association of the early attentive component with lexicons. In the schizophrenic patients, color-pattern implicit learning was positively correlated with P50 gating. The modality-specific impairment of implicit learning in schizophrenia may reflect a failure of adaptive filtering on the flooding input from color patterns.