Ting-pong Ho

Suicide notes: what do they tell us?

Police investigation records of all suicide cases in 1992 (n= 769) and the suicide notes that had been left (224 notes for 154 subjects) were examined. Note‐leavers were characterized as young females, of non‐widowed marital status, with no history of previous suicide attempts, no previous psychiatric illness, and with religious beliefs. Suicide notes written by young people were longer, rich in emotions, and often begging for forgiveness. Suicide notes written by the elderly were shorter, contained specific instructions, and were less emotional. A significant proportion of note‐leavers did mention their difficulties. Suicide notes may serve some explanatory purpose and may have a therapeutic role in helping the surviving relatives to understand the suicide. A knowledge of the messages contained within suicide notes could be useful for suicide prevention programmes. The significance of suicide notes is best understood within the context of the occurrence of suicides.

Dopamine receptor D4 (DRD4) gene in Han Chinese children with Attention-Deficit/Hyperactivity Disorder (ADHD): Increased prevalence of the 2-repeat allele

There is an increased prevalence of the 7‐repeat (7R) allele of the dopamine receptor D4 (DRD4) gene in attention‐deficit/hyperactivity disorder (ADHD). However, the population prevalence of the 7R allele varies considerably across ethnicity and is very low in Asians. To test whether this 7R allele/ADHD association still held in a Chinese clinical sample, 32 Han Chinese children with a confirmed ADHD diagnosis and normal IQ who were methylphenidate‐responders were genotyped. None of them had a DRD4 7R allele. Instead, we observed a significantly increased prevalence of the 2‐repeat (2R) allele in this clinical sample (33%) compared to ethnically‐matched controls (20%) (χ2(1d.f.) = 5.90, P = 0.015). This approximately 1.65‐fold increase of the 2R allele in our probands is close to the observed increase of the 7R allele in European‐ancestry ADHD children. Recent genetic studies have indicated that the 2R allele in Asians is likely derived from the 7R allele. Further, available biochemical data indicate that both the 2R and 7R protein have blunted responses to dopamine compared to the 4R protein. Based on these results, we propose that the observed increased prevalence of the 2R allele in our Han Chinese ADHD probands is still consistent with the 7R allele hypothesis of ADHD in European‐ancestry children. Recent studies have suggested that any variant from the conserved ancestral 4R allele might potentially alter biochemistry/phenotype. We hypothesize that an increased frequency of any non‐4R allele may define the association of the DRD4 gene with ADHD that holds across ethnicity. The present findings, however, obtained with a small ADHD sample size, should be replicated.

A re-examination of seasonal variation in suicides in Australia and New Zealand

BACKGROUND To examine the seasonality of suicides in Australia and New Zealand during the period 1981 to 1993. METHODS A chi-square test and a harmonic analysis were used to detect the seasonality of the suicide data. RESULTS The reduced amplitude and a smaller proportion of variance accounted for by seasonality suggested the seasonal effect on suicide is greatly diminished. The absence of biseasonal distribution of female suicides was also consistently found in the two countries. The finding was contrary to the reported results in seventies in many Western countries. CONCLUSIONS The change in living condition, roles of males and females and communication pattern resulted in the reduction of climatic and environment effect in the seasonality of suicides were suggested. LIMITATIONS The results would be better if a longer series of suicide date were available.

Age-related grey matter volume correlates of response inhibition and shifting in attention-deficit hyperactivity disorder

BACKGROUND Children with attention-deficit hyperactivity disorder (ADHD) have difficulties with executive function and impulse control which may improve with age. AIMS To map the brain correlates of executive function in ADHD and determine age-related changes in reaction times and brain volumes. METHOD Attention-deficit hyperactivity disorder and control groups were compared on the change task measures of response inhibition (stop signal reaction time, SSRT) and shifting (change response reaction time, CRRT). Voxel-wise magnetic resonance imaging (MRI) correlations of reaction times and grey matter volume were determined, along with bivariate correlations of reaction times, brain volumes and age. RESULTS Individuals in the ADHD group had longer SSRTs and CRRTs. Anterior cingulate, striatal and medial temporal volumes highly correlated with SSRT. Striatal and cerebellar volumes strongly correlated with CRRT. Older children had faster reaction times and larger regional brain volumes. In controls, orbitofrontal, medial temporal and cerebellar volumes correlated with CRRT but not SSRT. Neither reaction times nor regional brain volumes were strongly age-dependent. CONCLUSIONS Our evidence supports delayed brain maturation in ADHD and implies that some features of ADHD improve with age.

The Mental Health of the Peers of Suicide Completers and Attempters

This study examined the prevalence and risk of psychiatric disturbances and suicidal behaviours among the peers of suicide attempters and completers. The subjects were selected from high schools with and without history of student suicides in the past 3 years. The psychiatric disturbances (as measured by the YSR and CBCL), suicidal behaviours, drug use, and a wide range of potential risk factors were measured. About a quarter of the peers of suicide completers and attempters were probable psychiatric cases and 15-21% of them reported suicidal acts. The increased risk of psychiatric disturbances and suicidal behaviours were still evident after controlling for age, sex, and potential risk factors. The presence of psychiatric disturbances could not wholly account for the increased odds of suicidal behaviours. Peers of suicide attempters carried a higher risk than peers of suicide completers. The close friends of suicide completers were particularly at risk of internalising problems, whereas the close friends of suicide attempters were at high risk of externalising problems. The peers of suicide completers and attempters represent a high-risk group for psychiatric disturbances and suicidal behaviours. The specific association of different types of psychiatric disturbances in the peers of suicide completers and attempters suggested that different risk mechanisms might be in operation within these peer groups.

Seasonal variation in suicides re-examined: no sex difference in Hong Kong and Taiwan

The seasonal variation in suicides in Hong Kong and Taiwan during the period 1981 to 1993 was examined using harmonic analysis. A single cycle per year with lowest incidence in the winter months was found in both locations and for both sexes. Despite the regional differences in ascertainment procedures and preferred suicide methods, the absence of a biseasonal distribution of female suicides was consistently observed. This finding was contrary to that reported in many Western countries. A non‐shared psychosocial process underlying the cross‐cultural difference in the seasonality of female suicide is suggested.

Changing patterns of suicide in Hong Kong.

This paper aims to examine the changes in frequency, distribution and methods of suicide in the past 30 years in Hong Kong, and to explore the sociocultural factors behind such changes. Official data on suicides, undetermined deaths and seven social variables were used to estimate the age-, sex- and method-specific suicide rates and monthly occurrence of suicides, and to measure social changes. A low “anomie” status has been maintained for the past 30 years in Hong Kong. After accounting for undetermined deaths, suicide rates in adult males and young females (aged 15–24 years) decreased, while the rates in adult females remained stable. The phenomenon may be due to a protective effect of employment in males and by the changing status of women in Hong Kong. Suicide by jumping from heights became increasingly common, but appears to have substituted other means of suicide rather than increasing the overall suicide rate. Winter months had lower suicide rates, and the same circannual rhythm across diverse cultures speaks for a shared socio-biological process underlying suicide.

Characteristics of youth suicide in Hong Kong.

This paper explores the intrapersonal and sociocultural factors behind youth suicide in Hong Kong. The coroners court reports of consecutive population-based youth suicide (below age of 25 years,n=303) cases from 1986 to 1992 were reviewed. Compared with other countries, Hong Kong had low male but high female youth suicide rates. The number of undetermined deaths did not significantly affect the estimated suicide rates. Cross-cultural differences in youth suicide rates may be understood from a differential distribution of risk factors and cultural attitudes towards role behaviours and suicide. Youth suicides in Hong Kong were characterised by a high prevalence of psychiatric disturbances and age-normative precipitants; both findings bear great resemblances to samples studied elsewhere. The results were evaluated in light of studies in different sociocultural backgrounds and highlighted the universality and specificity of youth suicide in Hong Kong.

Help-seeking behaviours among child psychiatric clinic attenders in Hong Kong

This study employed semi-structured interviews and questionnaires to describe the help-seeking processes and examine the determinants of help-seeking behaviours in 100 consecutive referrals to a child psychiatric clinic in Hong Kong. The help-seeking processes were characterized by (1) a sequential pattern of lay consultations starting from the families, relatives, friends and, rarely, neighbours; (2) detour via multiple professionals; (3) delay in reaching specialist services. A total of seven psychosocial variables were used to predict the help-seeking behaviours. The younger the child was, the more likely members outside the families were sought for advice. A large number of professional consultations was predicted by a high symptom score and relative old age in the referred child, less social disadvantages in the family and parental beliefs that family influences were not the cause of the childs problems. A long delay in reaching specialist services was predicted by a high symptom score in the child. Parental beliefs of outside influences being the cause of the childs problems predicted a short delay in reaching the clinic. Low awareness of services was the predominant difficulty parents encountered when they sought psychiatric care for their children. Public health education to demystify the cause of mental distur-bances, close networking with teachers and general practitioners, and establishment of community child mental health clinics for easy access are recommended.

The test-retest reliability and screening efficiency of DISC Predictive Scales-version 4.32 (DPS-4.32) with Chinese children/youths

IntroductionThe DISC Predictive Scales-4.32 (DPS-4.32) were short-forms of the Diagnostic Interview Schedule for Children-IV (DISC-IV).MethodThe psychometric properties of DPS-4.32 were tested on two Chinese samples: a clinic sample of 83 children/youths, and a community sample of 541 youths.ResultsBoth Parent and Youth DPS-4.32 exhibited good-to-excellent test-retest reliability. Their screening efficiency was examined respectively against DSM-IV diagnoses of the full-length Parent and Youth DISC-IV. Results indicated large AUCs (Area under Receiver—Operating Charateristic Curve), as well as high sensitivity, specificity, and negative predictive values, supporting the capability of DPS-4.32 to differentiate cases from noncases.ConclusionDPS-4.32 held promise as efficient short-forms of DISC-IV, screening DSM-IV diagnoses. They were also applicable to the Chinese population, demonstrating their cross-cultural applicability.