Yiong Huak Chan

The prevalence and clinical characteristics of pruritus among patients with extensive psoriasis

Backgroundu2002Many patients with psoriasis are known to suffer from itch. However, the data available regarding itch and its characteristics in psoriasis are sparse. Objectivesu2002To examine the prevalence of pruritus and various related clinical characteristics in 101 patients with extensive psoriasis. Methodsu2002A structured questionnaire was used. Resultsu2002Generalized pruritus was a feature of psoriasis in 84% of the patients. In 77% of these it appeared on a daily basis. It involved all areas of the body, had prolonged duration and appeared mainly in the evening and at night. The pruritus significantly affected quality of life. Important daily factors that were found to exacerbate the itch were ambient heat (81%), skin dryness (80%), sweating (65%) and stress (55%). Important factors that were found to ameliorate itch were sleep (57%) and cold showers (55%). The pruritus was found to be unresponsive to most available antipruritics, including phototherapy. Itch intensity as reflected by a visual analogue scale did not correlate with Psoriasis Area and Severity Index scores; however, a highly significant correlation was obtained between the affective descriptors and itch intensity in the worst itch states (ru2003=u20030·6, Pu2003<u20030·001). Conclusionsu2002Pruritus is a common feature of psoriasis and affects quality of life.

Itch characteristics in Chinese patients with atopic dermatitis using a new questionnaire for the assessment of pruritus.

Background Although pruritus is the predominant and commonest feature of atopic dermatitis, its clinical characteristics have not been explored.

Clinical characteristics of pruritus in chronic idiopathic urticaria

Summary Backgroundu2003Although pruritus is a predominant symptom of chronic idiopathic urticaria (CIU) its clinical characteristics have not been explored.

Determinants of Duration of Untreated Psychosis and the Pathway to Care in Singapore

Introduction: Delays in providing effective treatment for a patient with psychosis has significant negative effects on the outcome. This includes more hospitalizations, longer periods of inpatient care, slower and less complete recovery, and more frequent relapses. In this study, we established the Duration of Psychosis (DUP) in a sample of patients with first-episode psychosis and examined the pathways to care. Methods: The sample comprised patients presenting with first-episode psychosis to the psychiatric services of the Institute of Mental Health, Singapore, from January to December 2000. The association between the DUP and demographic, clinical and social variables was examined. Results: The DUP ranged from 0.1 to 336 months. The mean DUP was 32.6 (SD 1/4 59.8) months, with a median of 12 months. Twenty four percent of the patients had sought consultation with a traditional healer prior to consulting a psychiatrist. The DUP of this group of patients was not significantly different from those who sought help elsewhere. Conclusions: The DUP of our patients was longer than that reported in studies done in the West. The attitudes and beliefs of family in the Asian society are likely to be crucial in the pathways to care.

Polymorphisms of dopamine receptors and tardive dyskinesia among Chinese patients with schizophrenia

The putative role of dopamine in the pathophysiology of tardive dyskinesia (TD) makes the genes coding for dopamine receptors the appropriate candidates for study. We investigate the association of the polymorphism of the Ser311Cys and Ser9Gly of the dopamine D2 (DRD2) and D3 receptor (DRD3) genes respectively with TD in Chinese patients with schizophrenia. In a case‐control study, 117 Chinese patients with TD were compared to 200 patients without TD. Patients were diagnosed to have schizophrenia according to DSM‐IV criteria. Dyskinesia was assessed by the Abnormal Involuntary Movement Scale (AIMS), whereas extrapyramidal side‐effects (EPSE) were assessed by the Simpson‐Angus Rating Scale. Genotype groups were comparable in age, gender, duration of illness, daily neuroleptic and benzodiazepine dose as well as the mean scores for EPSE. We failed to find an association between the polymorphism of the DRD2 gene with TD but found an increased risk of developing TD among those with D3 serine/serine genotype. Our results did not indicate that the D2 genotype has a role in the pathophysiology of TD in Chinese patients with schizophrenia. The association of TD with the serine/serine genotype of the DRD3 may be an epiphenomenon of patients with a subtype of schizophrenia who had more exposure to neuroleptics.

Do ethnicity and gender have an impact on pain thresholds in minor dermatologic procedures

Background and Objectives: The perception of pain is a personal experience influenced by many factors, including genetic, ethnic and cultural issues. Understanding these perceptions is especially important in dermatologic patients undergoing minor surgical operations and who often differ in their pain response to surgical treatments. Little is known about how these differences affect the perception of experimental pain. The purpose of this study was to determine experimental pain perception differences in three distinct East Asian ethnic populations.

A multiple regression approach to study optical components of myopia in Singapore school children

Purpose:u2002Previous studies on the optical components of childhood myopia adjusted only for age and gender or reported only the change of individual components with time. We perform a study to assess the association of the optical components of the eye contributing to the degree of myopia by building a statistical model which can better assess the individual effects of each optical component.