Anselm Ting Su

Haematological Reference Intervals in a Multiethnic Population

Introduction Similar to other populations, full blood count reference (FBC) intervals in Malaysia are generally derived from non-Malaysian subjects. However, numerous studies have shown significant differences between and within populations supporting the need for population specific intervals. Methods Two thousand seven hundred twenty five apparently healthy adults comprising all ages, both genders and three principal races were recruited through voluntary participation. FBC was performed on two analysers, Sysmex XE-5000 and Unicel DxH 800, in addition to blood smears and haemoglobin analysis. Serum ferritin, soluble transferrin receptor and C-reactive protein assays were performed in selected subjects. All parameters of qualified subjects were tested for normality followed by determination of reference intervals, measures of central tendency and dispersion along with point estimates for each subgroup. Results Complete data was available in 2440 subjects of whom 56% (907 women and 469 men) were included in reference interval calculation. Compared to other populations there were significant differences for haemoglobin, red blood cell count, platelet count and haematocrit in Malaysians. There were differences between men and women, and between younger and older men; unlike in other populations, haemoglobin was similar in younger and older women. However ethnicity and smoking had little impact. 70% of anemia in premenopausal women, 24% in postmenopausal women and 20% of males is attributable to iron deficiency. There was excellent correlation between Sysmex XE-5000 and Unicel DxH 800. Conclusion Our data confirms the importance of population specific haematological parameters and supports the need for local guidelines rather than adoption of generalised reference intervals and cut-offs.

The Clinical Features of Hand-arm Vibration Syndrome in a Warm Environment – A Review of the Literature

The Clinical Features of Hand‐arm Vibration Syndrome in a Warm Environment—A Review of the Literature: Anselm Ting SU, et al. Centre for Occupational and Environmental Health, University of Malaya, Malaysia—The internationally Accepted limit values and the health effects of hand‐transmitted vibration exposure have been described extensively in the literature from temperate climate countries but not from a tropical climate environment.

Dose-response relationship between hand-transmitted vibration and hand-arm vibration syndrome in a tropical environment

Objectives The dose–response relationship for hand-transmitted vibration has been investigated extensively in temperate environments. Since the clinical features of hand-arm vibration syndrome (HAVS) differ between the temperate and tropical environment, we conducted this study to investigate the dose–response relationship of HAVS in a tropical environment. Methods A total of 173 male construction, forestry and automobile manufacturing plant workers in Malaysia were recruited into this study between August 2011 and 2012. The participants were interviewed for history of vibration exposure and HAVS symptoms, followed by hand functions evaluation and vibration measurement. Three types of vibration doses—lifetime vibration dose (LVD), total operating time (TOT) and cumulative exposure index (CEI)—were calculated and its log values were regressed against the symptoms of HAVS. The correlation between each vibration exposure dose and the hand function evaluation results was obtained. Results The adjusted prevalence ratio for finger tingling and numbness was 3.34 (95% CI 1.27 to 8.98) for subjects with lnLVD≥20 ln m2 s−4 against those <16 ln m2 s−4. Similar dose–response pattern was found for CEI but not for TOT. No subject reported white finger. The prevalence of finger coldness did not increase with any of the vibration doses. Vibrotactile perception thresholds correlated moderately with lnLVD and lnCEI. Conclusions The dose–response relationship of HAVS in a tropical environment is valid for finger tingling and numbness. The LVD and CEI are more useful than TOT when evaluating the dose–response pattern of a heterogeneous group of vibratory tools workers.

Pegylated granulocyte-colony stimulating factor versus non-pegylated granulocyte-colony stimulating factor for peripheral blood stem cell mobilization: A systematic review and meta-analysis

Granulocyte‐colony stimulating factor (G‐CSF) mobilizes and increases the amount of hematopoietic stem cells in peripheral blood, enabling its harvest by few apheresis procedures. The pegylated G‐CSF has longer half‐life and is given once only, which is more comfortable for patients, whereas the non‐pegylated requires multiple daily injection because of its short half‐life. We summarized results of randomized trials comparing the efficacy and safety of pegylated and non‐pegylated G‐CSF for peripheral blood stem cell mobilization. We searched the Cochrane CENTRAL, MEDLINE, EMBASE, and two conference proceedings. Two authors made the selection, extracted data and evaluated methodological quality using GRADE independently. We used random‐effects model for meta‐analysis. We found 3956 records and retrieved 47 full texts. We included eight randomized trials with a total number of 554 randomized and 532 analyzed subjects. The meta‐analysis included five trials because not all trials reported the same outcomes. Pooling data from two studies shows no evidence for a difference in the successful mobilization rate (CD34+ cell ≥ 2 × 106/kg collected) between pegfilgrastim 6 mg (early administration) and filgrastim 5 µg/kg/day (147 participants; risk ratio (RR) 0.87, 95% confidence interval (95%CI) 0.67‐1.11; P = .26). Pooling data from three studies shows no difference in the incidence of adverse events between pegylated and non‐pegylated G‐CSF (170 participants; RR 0.86, 95%CI 0.34‐2.17; P = .75). No difference found on the quantity of CD34+ cells collected, number of apheresis procedure in successful mobilization, level of peak PB CD34+ cells achieved, and day of neutrophil and platelet engraftment.

A Cross Sectional Study on Hand-arm Vibration Syndrome among a Group of Tree Fellers in a Tropical Environment

This study aimed to explore the clinical characteristics of hand arm vibration syndrome (HAVS) in a group of tree fellers in a tropical environment. We examined all tree fellers and selected control subjects in a logging camp of central Sarawak for vibration exposure and presence of HAVS symptoms utilizing vibrotactile perception threshold test (VPT) and cold water provocation test (CWP). None of the subjects reported white finger. The tree fellers reported significantly higher prevalence of finger coldness as compared to the control subjects (OR=10.32, 95%CI=1.21–87.94). A lower finger skin temperature, longer fingernail capillary return time and higher VPT were observed among the tree fellers as compared to the control subjects in all fingers (effect size >0.5). The VPT following CWP of the tree fellers was significantly higher (repeated measures ANOVA p=0.002, partial η2=0.196) than the control subject. The A (8) level was associated with finger tingling, numbness and dullness (effect size=0.983) and finger coldness (effect size=0.524) among the tree fellers. Finger coldness and finger tingling, numbness and dullness are important symptoms for HAVS in tropical environment that may indicate vascular and neurological damage due to hand-transmitted vibration exposure.

The Effectiveness of Applying Different Permissible Exposure Limits in Preserving the Hearing Threshold Level: A Systematic Review

The Effectiveness of Applying Different Permissible Exposure Limits in Preserving the Hearing Threshold Level: A Systematic Review; Balachandar S. SAYAPATHI, et al. Centre for Occupational and Environmental Health, University of Malaya, Malaysia—

A Comparison of Hand-arm Vibration Syndrome between Malaysian and Japanese Workers

A Comparison of Hand‐arm Vibration Syndrome between Malaysian and Japanese Workers: Anselm Ting SU, et al. Centre for Occupational and Environmental Health, Department of Social and Preventive Medicine, University of Malaya, Malaysia—The evidence on hand‐arm vibration syndrome (HAVS) in tropical environments is limited. The legislation for the control of occupational vibration exposure has yet to be established in Malaysia.

511 Workplace bullying and metabolic syndrome among private sector workforce in malaysia

Introduction Workplace bullying is increasingly recognised as a serious public health issue in the workplace because of its increasing prevalence worldwide and negative health impacts on employee’s health. The consequences vary from stress and depression to psychosomatic problems including cardiovascular diseases. The objective of this study is to determine the prevalence of workplace bullying and its association with metabolic syndrome among private industry workers in Malaysia. Methods Workers undergoing Health Screening Program (HSP) by Social Security Organisation Malaysia in a private healthcare laboratory throughout Malaysia were recruited into the study. The targeted sample size was 1580 participants throughout the country. Workplace bullying was measured using Modified Negative Acts Questionnaire and Malaysian Workplace Bullying Index. Data collected from the HSP was analysed to determine the presence of metabolic syndrome. The relationship between the presence of workplace bullying and metabolic syndrome was analysed using SPSS software. Results Preliminary results showed most of the respondents experienced more on workrelated bullying than person-related bullying. Age and waist circumference were significantly associated with workplace bullying. There was no significant association between workplace bullying and other parameters of metabolic syndrome. Data collection is still in progress and will be completed by February 2018. Conclusion The prevalence of workplace bullying is related to age and possible obesity. Its association with metabolic syndrome is inconclusive for the time being.

461 Workplace bullying and its association with depression and self-esteem among health care workers in selected hospitals in sarawak

Introduction Bullying at the workplace has been recognised as an increasing problem amongst healthcare staff, and has been associated with a low self-esteem and depression. Considering this view, this study was aimed to determine the proportion of bullying amongst healthcare workers in selected hospitals in Sarawak and its association between depression and self-esteem. Methods A cross sectional study using self-administered questionnaires was done in three selected hospitals in Sarawak. The questionnaires were distributed to doctors, nurses and medical assistants during their teaching sessions. The questionnaires consisted of socio-demographics, Negative Acts Questionnaire (NAQ), Beck Depression Inventory (BDI), and Rosenberg Self-Esteem (RSE) scale. A total of 426 samples were included for analysis, after discarding 72 samples due to grossly missing information. The response rate was 71.1%. Results Majority of the respondents were of the age group 25 to 29 years old. Nurses comprised 45.5% of the study population, followed by doctors (37.8%), whilst the rest were medical assistants and midwives. Based on the definition of bullying as at least two occurrences of any negative act either on a weekly or daily basis, 20.7% of respondents had been bullied. 22.5% of the study group had mild to severe depression, and 8.5% had a low self-esteem. There was an association between depression and being bullied, with a p value of<0.001. Those healthcare workers who had a low self-esteem were associated with higher exposure to bullying, with a p value<0.001. The factors associated with bullying were the younger age group, shorter length of service, shifting work, non-managerial position and the designation as a doctor. Conclusion A significant proportion of healthcare workers had been bullied, and bullying exposure was shown to be associated with depression and low self-esteem. Hence, regular screening for bullying, depression and low self-esteem should be done to enable early intervention.

The Impact of Different Permissible Exposure Limits on Hearing Threshold Levels Beyond 25 dBA

Background: Development of noise-induced hearing loss is reliant on a few factors such as frequency, intensity, and duration of noise exposure. The occurrence of this occupational malady has doubled from 120 million to 250 million in a decade. Countries such as Malaysia, India, and the US have adopted 90 dBA as the permissible exposure limit. According to the US Occupational Safety and Health Administration (OSHA), the exposure limit for noise is 90 dBA, while that of the US National Institute of Occupational Safety and Health (NIOSH) is 85 dBA for 8 hours of noise exposure. Objectives: This study aimed to assess the development of hearing threshold levels beyond 25 dBA on adoption of 85 dBA as the permissible exposure limit compared to 90 dBA. Patients and Methods: This is an intervention study done on two automobile factories. There were 203 employees exposed to noise levels beyond the action level. Hearing protection devices were distributed to reduce noise levels to a level between the permissible exposure limit and action level. The permissible exposure limits were 90 and 85 dBA in factories 1 and 2, respectively, while the action levels were 85 and 80 dBA, respectively. The hearing threshold levels of participants were measured at baseline and at first month of postshift exposure of noise. The outcome was measured by a manual audiometer. McNemar and chi-square tests were used in the statistical analysis. Results: We found that hearing threshold levels of more than 25 dBA has changed significantly from pre-intervention to post-intervention among participants from both factories (3000 Hz for the right ear and 2000 Hz for the left ear). There was a statistically significant association between participants at 3000 Hz on the right ear at ‘deteriorated’ level ( χ² (1) = 4.08, φ = - 0.142, P = 0.043), whereas there was worsening of hearing threshold beyond 25 dBA among those embraced 90 dBA. Conclusions: The adoption of 85 dBA as the permissible exposure limit has preserved hearing threshold level among participants at 3000 Hz compared to those who embraced 90 dBA.