SARS-CoV-2 seroprevalence and antibody trends in vaccinated, multi-ethnic healthcare employees.

Understanding of antibody kinetics against SARS-CoV-2 and its vaccines is rapidly evolving. This study aims to (1) determine post-vaccination seroprevalence; (2) compare antibody levels between vaccine types and various clinical/demographic determinants; and (3) determine post-vaccination antibody concentrations against time. This is a retrospective cross-sectional study involving 148 healthcare employees all over Malaysia. IgG Spike (RBD), IgM Spike and IgG Nucleocapsid concentration medians were compared using Mann-Whitney U or Kruskal-Wallis tests. Chi Square and Spearman correlation coefficient tests were performed to identify variables associated with antibody titers. A scatter plot of IgG Spike (RBD) against time from last vaccine dose was also plotted. At 1-month post-vaccination, all employees successfully seroconverted regardless of vaccine type, health status and COVID- 19 history. Comirnaty, convalescent, female or Malay vaccinees had significantly higher IgG Spike (RBD) titers compared to their respective counterparts. No correlation was found between age and IgG Spike (RBD) levels. Concentration of all three antibodies waned with time post-vaccination, with IgM Spike and IgG Nucleocapsid waning faster than IgG Spike (RBD).

SARS-CoV-2 seroprevalence and antibody trends in vaccinated, multi-ethnic healthcare employees

@#Understanding of antibody kinetics against SARS-CoV-2 and its vaccines is rapidly evolving. This study aims to (1) determine post-vaccination seroprevalence; (2) compare antibody levels between vaccine types and various clinical/demographic determinants; and (3) determine post-vaccination antibody concentrations against time. This is a retrospective cross-sectional study involving 148 healthcare employees all over Malaysia. IgG Spike (RBD), IgM Spike and IgG Nucleocapsid concentration medians were compared using Mann-Whitney U or Kruskal-Wallis tests. Chi Square and Spearman correlation coefficient tests were performed to identify variables associated with antibody titers. A scatter plot of IgG Spike (RBD) against time from last vaccine dose was also plotted. At 1-month post-vaccination, all employees successfully seroconverted regardless of vaccine type, health status and COVID19 history. Comirnaty, convalescent, female or Malay vaccinees had significantly higher IgG Spike (RBD) titers compared to their respective counterparts. No correlation was found between age and IgG Spike (RBD) levels. Concentration of all three antibodies waned with time post-vaccination, with IgM Spike and IgG Nucleocapsid waning faster than IgG Spike (RBD).

Restless legs symptoms in thyroid disorders.

Dopaminergic dysfunction is associated with thyroid disorders and restless legs syndrome (RLS). In a 'face-to-face' interview, we evaluated for RLS using the diagnostic criteria of the International Restless Legs Syndrome Study Group (IRLSSG) in patients diagnosed biochemically with either hyper- or hypothyroidism, and in controls without thyroid disorders. Amongst 146 consecutive patients with biochemically confirmed thyroid disorders, none satisfied all the IRLSSG criteria of RLS, similar to the control population (0.2%, 1/434). However, we found 8.2% (12/146) with RLS-like symptoms (satisfied the first 3 IRLSSG criteria) compared to 0.9% (4/434) in the controls (p < 0.0001). Four (33.3%) of these patients reported complete resolution of these symptoms after treatment for their thyroid condition. In conclusion, while RLS-like symptoms were observed in some patients with thyroid disorders, our study demonstrates no significant difference of RLS prevalence between patients with thyroid disorders and euthyroid controls.

Statin therapy and small fibre neuropathy: a serial electrophysiological study.

We describe three patients who developed small fibre neuropathy after 1 month of statin therapy with clinical resolution upon prompt drug withdrawal. All patients showed abnormal sympathetic skin responses (SSR) in comparison with controls. SSRs returned to normal in tandem with clinical improvement. One patient redeveloped small and large fibre neuropathy when the similar drug was readministered. The SSR is of value in the electrophysiological assessment and follow-up of statin-related small fibre neuropathy.

The TaqIB and -629C>A polymorphisms at the cholesteryl ester transfer protein locus: associations with lipid levels in a multiethnic population. The 1998 Singapore National Health Survey.

The Singapore population comprises Chinese, Malays and Asian Indians. Within this population, Asian Indians have the highest rates of coronary heart disease, whereas Chinese have the lowest. Conversely, Indians have the lowest high-density lipoprotein cholesterol (HDL-C) concentrations, followed by Malays and Chinese. We studied the TaqIB and -629C>A polymorphisms at the CETP locus in 1300 Chinese, 364 Malay and 282 Asian Indian men, and in 1558 Chinese, 397 Malay and 306 Asian Indian women, to determine whether these polymorphisms are responsible for the ethnic difference in HDL-C concentration. The frequency of the B2 allele in Chinese, Malays and Indians was 0.384, 0.339 and 0.449 in men, and 0.379, 0.329 and 0.415 in women, respectively (p < 0.001). For the A-629 allele, the relative frequencies were 0.477, 0.423 and 0.592 in men and 0.486, 0.416 and 0.575 in women (p < 0.001). The two polymorphisms were in linkage disequilibrium (D / Dmax= 0.9772, p < 0.00001). The B2 and the A-629 alleles were associated with increased HDL-C concentrations in a dose-dependent manner. The B2 allele continued to show an association with HDL-C concentration, even after controlling for the genotype at position -629. Dietary cholesterol showed a significant interaction with the TaqIB polymorphism in determining HDL-C concentrations in Indians and Malays, but not in Chinese. In conclusion, the high frequencies of these polymorphisms in Asian Indians could not explain the observed ethnic differences in HDL-C concentration. Moreover, we observed an ethnic-specific interaction among dietary cholesterol, the TaqIB polymorphism and HDL-C concentrations.

Do Singapore patients require lower doses of statins? The SGH Lipid Clinic experience.

A substantial number of physicians in Asian countries believe that Asian patients need lower doses of statins to achieve therapeutic lipid target because of the smaller size of patients. This belief is deep rooted and we looked at the SGH Lipid Clinic to determine if our experience bears out this belief. Between 1996 and August 2000, the Lipid Unit treated a total of 841 patients, of which 548 patients (77.5% Chinese, 12.1% Malays, 7.6% Asian Indians; 49.6% males, 50.4% females; 54.7% diabetics, 45.3% non-diabetic) were on statins alone. These patients had > or =2 coronary risk factors, diabetes mellitus or documented coronary heart disease. The pre-treatment lipid levels or the worst lipid levels available were entered as the baseline lipid values (mean LDL-C: 5.38+1.5 mmol/l). Duration of therapy ranged from six months to five years. The choice and titration of statins were determined by attending physicians. The median statin dose (Simvastatin equivalent) was 20.0 mg with 52.5% requiring 20 mg or more. Statin dose did not differ between diabetic and non-diabetic subjects. The median statin dose was 15 mg for the lower two tertiles and 20 mg for the upper tertile; this difference did not achieve statistical significance. The reduction in LDL cholesterol was 41.5% (40.1-42.8) and total cholesterol was 33.0% (32.9-34.1). Only 25% of our patients achieved LDL cholesterol of less than 2.6 mmol/l whilst 77.5% had LDL cholesterol less than 3.4 mmol/l. Our experience at the Lipid Clinic suggests that the Asian patients require similar statin doses to achieve target cholesterol levels.

Compound heterozygous familial hypercholesterolemia and familial defective apolipoprotein B-100 produce exaggerated hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) and familial defective apolipoprotein B-100 (FDB) represent ligand-receptor disorders that are complementary. Individuals with both FH and FDB are unusual. We report a family with both disorders and the impact of the mutations on the phenotypes of the family members. METHODS: We used single strand conformation polymorphism (SSCP) and denaturing gradient gel electrophoresis (DGGE) for genetic analysis of all 18 exons and the promoter region of the LDL receptor and DGGE for genetic analysis of the apolipoprotein B-100 (apo B-100) gene. The functional significance of the apo B-100 mutation was studied using a U937 cell proliferation assay. Fasting serum lipid profiles were determined for the index case and seven first-degree relatives. RESULTS: One of the patient's sisters had a missense mutation (Asp(407)-->Lys) in exon 9 of the LDL receptor and a serum LDL-cholesterol concentration of 4.07 mmol/L. Four other first-degree relatives had hyperlipidemia but no LDL-receptor mutation. However, these subjects had a mutation of the apo B-100 gene (Arg(3500)-->Trp). The cell proliferation rate of U937 cells fed with LDL from other subjects with the same mutation was fourfold less than that of controls. The index case had both FH- and FDB-related mutations. Her serum LDL-cholesterol (9.47 mmol/L) was higher than all other relatives tested. CONCLUSIONS: Existence of both FH and FDB should be considered in families with LDL-receptor mutations in some but not all individuals with hypercholesterolemia or when some individuals in families with FH exhibit exaggerated hypercholesterolemia.

Benefits of micronised Fenofibrate in type 2 diabetes mellitus subjects with good glycemic control.

AIMS: To determine the effects of micronised fenofibrate on lipids and low density lipoprotein (LDL) subfraction in well-controlled diabetic subjects with mild elevations in cholesterol levels. METHODS: Thirty-five male type 2 diabetic subjects with LDL(3) greater than 100 mg/dl and good glycemic control (mean HbA1c 6.7%) were treated with micronised fenofibrate in an open labeled study for 6 months. Anthropometric indices, blood pressure, lipids, glucose, insulin, apolipoprotein A-I and B, and LDL subfraction by density ultracentrifugation were obtained after an overnight fast of 10 h, at the beginning and end of the 6 months treatment period. RESULTS: The blood pressure, waist to hip ratio, body mass index and glycemic control remained unchanged throughout the 6 months study period. Mean serum triglyceride fell from 2.49 to 1.72 mmol/l (33%) whilst HDL cholesterol increased from 0.88 to 0.96 mmol/l (10.8%). There were no significant changes in total or LDL cholesterol. Both LDL(1) and LDL(2) rose significantly whilst the dense LDL(3) fell from a mean of 148 to 85 mg/dl (43% reduction). Fenofibrate changed the LDL subfraction distribution from dense LDL(3) particles towards buoyant LDL(1) and LDL(2) particles in 63% of the subjects. No subjects had elevations in transaminases greater than three-fold or creatine kinase greater than ten-fold from pre-treatment levels. CONCLUSION: Diabetic subjects with mild hypercholesterolemia and good glycemic control may benefit from therapy with micronised fenofibrate because of the reduction in serum triglyceride, elevation in HDL cholesterol and a shift in LDL subfraction towards a non-atherogenic form.