Thalassemia Phenotypes and Genotypes in Taiwan: A Retrospective Study Based on Thalassemia Screening of Young Men for Military Conscription

Anemia after pancreaticoduodenectomy in patients followed-up for 5 years

BACKGROUND

Anemia is a common long-term metabolic sequela caused by anatomical changes after major gastrointestinal surgery, such as bariatric surgery and gastrectomy. Pancreaticoduodenectomy (PD) involves resection of the duodenum and enteral bypass, which may contribute to malabsorption and nutrient deficiency. Hence, PD may cause anemia.

METHODS

This study included 322 patients who presented with PD during the 5-year follow-up from 2006 to 2017. The Kaplan-Meier method and the Cox regression model were used to investigate the association between risk factors and anemia.

RESULTS

Approximately 44.4% of patients developed post-PD anemia during the 5-year post-PD follow-up. Further, 30 (9.3%) patients were treated with oral iron supplementation for anemia with associated symptoms. In the Cox multivariate model, a higher Charlson Comorbidity Index (CCI) score and pancreatic ductal adenocarcinoma were significantly associated with the development of post-PD anemia.

CONCLUSION

Post-PD anemia is a common sequela among long-term survivors. A higher CCI and pancreatic ductal adenocarcinoma diagnosis were considered as independent risk factors for post-PD anemia. Therefore, regular monitoring of hematological profiles and appropriate management of post-PD anemia are required during follow-up.

Causal links of α-thalassemia indices and cardiometabolic traits and diabetes: MR study

Our study aimed to investigate if genetic variants around 16p13.3's HBA1 locus, associated with erythrocyte indices and HbA1c levels, predict α-thalassemia-related erythrocyte indices, cardiometabolic traits, and diabetes risk in Taiwanese individuals. We analyzed Taiwan Biobank data, including whole-genome sequencing from 1,493 participants and genotyping arrays from 129,542 individuals. First, we performed regional association analysis using whole-genome sequencing data to identify genetic variants significantly associated with erythrocyte indices, confirming their linkage disequilibrium with the α0 thalassemia --SEA deletion mutation, a common cause of α-thalassemia in Southeast Asian populations. Deletion mutation sequencing further validated these variants' association with α-thalassemia. Subsequently, we analyzed genotyping array data, revealing associations between specific genetic variants and cardiometabolic traits, including lipid profiles, HbA1c levels, bilirubin levels, and diabetes risk. Using Mendelian randomization, we established causal relationships between α-thalassemia-related erythrocyte indices and cardiometabolic traits, elucidating their role in diabetes susceptibility. Our findings highlight genetic variants around the α-globin genes as surrogate markers for common α-thalassemia mutations in Taiwan, emphasizing the causal links between α-thalassemia-related erythrocyte indices, cardiometabolic traits, and heightened diabetes risk.

A validation and modification of PLASMIC score by adjusting the criteria of mean corpuscular volume and international normalized ratio

BACKGROUND

The PLASMIC score was developed for distinguishing thrombotic thrombocytopenic purpura (TTP) from other types of thrombotic microangiopathy. However, two components of the PLASMIC score, mean corpuscular volume (MCV) and international normalized ratio (INR), showed non-significant differences between TTP and non-TTP patients in previous validations. Here, we validate the PLASMIC score and aim to modify it by adjusting the criteria of MCV and INR.

MATERIALS AND METHODS

A retrospective validation of suspected TTP patients was performed by reviewing electronic medical records from two medical centers in Taiwan. The performance of different modified types of the PLASMIC score was carried out.

RESULTS

Among 50 patients included in the final analysis, 12 were diagnosed with TTP based on deficiency of ADAMTS13 activity and clinical judgement. When stratified by high (score ≥ 6) and low-intermediate risk (score < 6), the positive predictive value (PPV) of the PLASMIC score to predict TTP was 0.45 (95% confidence interval [CI]: 0.29-0.61). The area under curve (AUC) was 0.70 (95% CI: 0.56-0.82). When adjusting the criteria of the PLASMIC score from MCV < 90 fL to MCV ≥ 90 fL, the PPV increased to 0.57 (95% CI: 0.37-0.75). The AUC was 0.75 (95% CI: 0.61-0.87). When adjusting the INR from >1.5 to >1.1, the PPV increased to 0.56 (95% CI: 0.39-0.71). The AUC was 0.81 (95% CI: 0.68-0.90).

CONCLUSION

MCV ≥ 90 fL and/or INR > 1.1 might be suitable modifications for PLASMIC score but should be validated in a larger sample size.

Influence of hemoglobin on blood pressure among people with GP.Mur blood type☆

BACKGROUND/PURPOSE

GP.Mur is a clinically important red blood cell (RBC) type. GP.Mur and band 3 interact on the RBCs. We previously observed that healthy adults with GP.Mur type present slightly higher blood pressure (BP). Because band 3 and Hb comodulate nitric oxide (NO)-dependent vasodilation and hemoglobin (Hb) is positively associated with BP, we aimed to test whether these could contribute to higher BP in GP.Mur+ people.

METHODS

We recruited 989 non-elderly adults (21% GP.Mur) free of catastrophic illness and not on cardiovascular or anti-hypertensive medication. Their body indices, blood lab data and lifestyle data were collected for analyses of potential BP-related factors (BMI, age, smoking, Hb, and GP.Mur).

RESULTS

BMI and age remained the most significant contributors to BP. GP.Mur slightly increased systolic BP (SBP). The direct correlation between Hb and BP was only found in Taiwanese non-anemic men, not women. After age and BMI adjusted, we estimated an increase of 1.8 mmHg and 2.6 mmHg of SBP by 1 g/dL Hb among men without and with GP.Mur type, respectively. Hb was generally lower among people expressing GP.Mur, which likely limited their larger impact on BP.

CONCLUSION

GP.Mur contributed to BP in both Hb-dependent and Hb-independent fashion. A pronounced impact of hemoglobin on BP likely requires sufficient Hb, as GP.Mur increased the sensitivity of SBP to Hb only in non-anemic Taiwanese men, and not in Taiwanese women or anemic men. The mechanism through which GP.Mur affected BP independent of Hb is unknown.