Discordance between Fasting Plasma Glucose (FPG) and HbA1c in Diagnosing Diabetes and Pre-diabetes in The Malaysian Cohort / Journal of the ASEAN Federation of Endocrine Societies

Objective@#In this present study, we aim to evaluate the accuracy of the HbA1c relative to fasting plasma glucose (FPG) in the diagnosis of diabetes and pre-diabetes among The Malaysian Cohort (TMC) participants.@*Methodology@#FPG and HbA1c were taken from 40,667 eligible TMC participants that have no previous history of diabetes, aged between 35-70 years and were recruited from 2006 – 2012. Participants were classified as normal, diabetes and pre-diabetes based on the 2006 World Health Organization (WHO) criteria. Statistical analyses were performed using ANOVA and Chi-square test, while Pearson correlation and Cohen’s kappa were used to examine the concordance rate between FPG and HbA1c.@*Results@#The study samples consisted of 16,224 men and 24,443 women. The prevalence of diabetes among the participants was 5.7% and 7.5% according to the FPG and HbA1c level, respectively. Based on FPG, 10.6% of the participants had pre-diabetes but this increased to 14.2% based on HbA1c (r=0.86; P<0.001). HbA1c had a sensitivity of 58.20 (95% CI: 56.43, 59.96) and a specificity of 98.59 (95% CI: 98.46, 98.70).@*Conclusion@#A higher prevalence of pre-diabetes and diabetes was observed when using HbA1c as a diagnosis tool, suggesting that it could possibly be more useful for early detection. However, given that HbA1c may also have lower sensitivity and higher false positive rate, several diagnostic criteria should be used to diagnose diabetes accurately.

Glucocerebrosidase genetic variants in Malays with early and late-onset Parkinson’s disease

@#Background: Mutations in glucocerebrosidase (GBA) have been associated with the risk of developing Parkinson’s disease (PD) in different ethnic populations. The prevalence of GBA mutations among Malay PD patients is unknown. Thus, the aim of this study was to determine the frequency of GBA mutations among Malay PD patients, focusing on early (EOPD) and late-onset (LOPD) patients. Methods:EOPD (n = 50) and LOPD (n = 50) patients along with 50 ethnically and age-matched control wererecruited. The GBA exons of these patients were sequenced using the Ion Torrent PGMTM System. Results: Five heterozygous mutations exclusive to EOPD patients were identified; c.-203A>G,p.S146L, p.R159Q, p.L483P and p.L483R+c.-145G>A. In LOPD patients, c.543C>T(p.(F181=)), c.28-10C>A and p.R202Q were identified in which this p.R202Q was also present in a control subject. In addition, c.259C>A(p.(R87=)) and c.-145G>A were identified in two control subjects. In summary, we observed GBA mutations in 8% and 6% of Malay PD cases and control subject, respectively. The prevalence of GBA mutations was higher in EOPD (10%) than LOPD (6%). However, these differences were not statistically significant; [PD vs. controls: OR = 1.36, 95%CI 0.35-5.38, p = 0.752] and [EOPD vs. LOPD: OR = 1.74, 95%CI 0.39-7.71, p = 0.715]. Conclusion: We identified five exclusive heterozygous GBA mutations in EOPD patients which might predict the increase susceptibility of Malays to develop PD at young age. These findings could add knowledge into the existing evidences linking genetic alterations in GBA and PD.

Differential expression of circulating miRNAs in Parkinson’s disease patients: Potential early biomarker?

@#Background & Objective: Circulating microRNAs (miRNAs) expressions have been suggested as potential biomarkers for Parkinson’s Disease (PD). Identification of early biomarkers for PD is important and crucial as PD symptoms occur at a late stage. Hence, these biomarkers could be used in molecular diagnosis for early detection. We therefore examined and compared the expression of circulating miRNAs between PD patients and controls. We also compared the miRNAs expression between early-onset PD (EOPD) and late-onset PD (LOPD). Methods: RNA was extracted from the plasma of EOPD (onset age <50 years; n=14), LOPD (onset age < 60 years; n=14) and healthy controls (n=11). The miRNAs expression was determined using the Affymetrix GeneChip microarray. Differential analysis was performed using the R software. Significantly differentiated miRNAs were subsequently analyzed for functional enrichment and biological pathway using the FunRich v1.3 software based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The Omics.net was used to determine the predicted target mRNAs of these miRNAs, and their interactions, based on the five most differentially expressed miRNAs. Results: In total, 273 miRNAs were upregulated in PD patients compared to controls. The most significant miRNAs were hsa-miR-301a-3p, 100-5p, 140-5p, 486-3p, 143-3p (fold change ranging from 11.2 – 32.0). A total of 140 circulating miRNAs were differentially expressed in EOPD compared to LOPD. Five of these miRNAs (one upregulated miRNA (hsa-miR-29b-3p) and four downregulated miRNAs (hsa-miR-297, 4462, 1909-5p and 346) belonged exclusively to the EOPD patients. The predicted gene targets of these miRNAs involved in dopaminergic synapse regulation, crucial to the pathogenesis of PD. Conclusion: Circulating miRNAs differ between PD patients and controls, and between EOPD and LOPD patients. A validation study with a larger and more diverse multi-ethnic population should be conducted to confirm our results.

HLA-B*15:02 screening in epileptic patients using a high resolution melting-real time PCR (HRM-QPCR) method

Background: The HLA-B*15:02 polymorphism in epileptic patients is known to be associated with carbamazepine-induced Stevens-Johnson syndrome (SJS). The prevalence of HLA-B*15:02 polymorphism seemed to be ethnic-specific with a higher frequency of HLA-B*15:02 in Asian compared to the Europeans. This study was performed to determine the frequency of the HLA-B*15:02 polymorphism in epileptic patients at the Chancellor Tuanku Muhriz Hospital-UKM Medical Centre (HCTM-UKMMC) using high resolution melting-real time PCR (HRM-QPCR) method. Methods: We performed a fast and effective in-house high resolution melting-real time polymerase chain reaction method and compared it with the conventional multiplex-PCR method. The specificity and sensitivity of each test were also determined using DNA from saliva. Results: Using the conventional multiplex-PCR approach for screening, 25 out of 64 (39.1%) epileptic patients were positive for HLA-B*15:02. However, using the HRM-QPCR technique, 24/64 (37.5%) of the patients were positive. The one patient who tested positive by the multiplex-PCR but negative using the HRM-QPCR turned out to be negative by DNA sequencing. The HRM-QPCR and DNA sequencing showed 100% sensitivity and specificity. The multiplex-PCR showed 100% sensitivity and 98.4% specificity compared to both HRM-QPCR and DNA sequencing. The HRM-QPCR is also more cost-effective (<$16.40 USD/test) and less time-consuming when compared to the multiplex-PCR ($25.15 USD/test).Conclusion: Our result suggested that multiplex PCR, HRM-QPCR and Sanger sequencing can be used for detection of HLA-B*15:02. However, a qualitative method such as multiplex PCR should be confirmed with other quantitative methods such as HRM-QPCR and Sanger sequencing.

Impulse control behaviours in a Malaysian Parkinson’s disease population

Background: Impulse control behaviours are repetitive and excessive activities that may be subsyndromal and not fulfil the criteria for impulse control disorder. These activities have potential to negatively impact on the daily lives of sufferers. We conducted a study to investigate the prevalence of impulse control behaviours and its associated features in Parkinson’s disease in our population. Methods: We conducted a prospective cross-sectional study on consecutive patients attending neurology clinic. Inclusion criteria include idiopathic Parkinson’s disease patients with Hoehn & Yahr stage I-IV. Eighty patients were enrolled and screened for impulse control behaviours using the Questionnaire for Impulsive-Compulsive Disorder for Parkinson’s disease (QUIP). Results: Prevalence of impulse control behaviours among our cohort was 11.3%; the features significantly associated with it were higher level of education (p=0.02), advanced stage of disease (p=0.03) and higher levodopa dosage (p= 0.01). The commonest impulse control behaviour in our cohort was compulsive medication use (7.5%), followed by hobbyism (6.3%), hypersexuality (5%), compulsive buying (3.75%), punding (2.5%), walkabout (2.5%), compulsive eating (1.25%) and pathological gambling (1.3%). Conclusions: There is an association between impulse control behaviour and higher levodopa dosage in a study on patients with Parkinson’s disease in Malaysia. We also found a low prevalence of pathological gambling as compared to studies performed in the West.

Hb Lepore/β0-Thalassaemia With α+-Thalassaemia Interactions, A Potential Diagnostic Pitfall

Haemoglobin (Hb) Lepore is a variant Hb consisting of two α-globin and two δβ-globin chains. In a heterozygote, it is associated with clinical findings of thalassaemia minor, but interactions with other haemoglobinopathies can lead to various clinical phenotypes and pose diagnostic challenges. We reported a pair of siblings from a Malay family, who presented with pallor and hepatosplenomegaly at the ages of 21 months and 14 months old. The red cell indices and peripheral blood smears of both patients showed features of thalassaemia intermedia. Other laboratory investigations of the patients showed conflicting results. However, laboratory investigation results of the parents had led to a presumptive diagnosis of compound heterozygote Hb Lepore/β-thalassaemia and co-inheritance α+-thalassaemia (-α3.7). Hb Lepore has rarely been detected in Southeast Asian countries, particularly in Malaysia. These two cases highlight the importance of family studies for accurate diagnosis, hence appropriate clinical management and genetic counseling.