Changes in spike protein antibody titer over 90 days after the second dose of SARS-CoV-2 vaccine in Japanese dialysis patients

Objectives

There is no report on antibody titers after vaccination against SARS-CoV-2 in Japanese dialysis patients. As dialysis is different between Japan and other countries, changes in antibody titers were examined.

Methods

Baseline characteristics and anti-spike protein antibody titers (Roche) over 90 days after administration of the BNT162b2 messenger RNA vaccine were investigated in dialysis patients.

Results

The maximum anti-spike protein antibody titer after the second dose was 738 (327 to 1143) U/mL and was reached at 19 (17 to 24) days after the second dose. Antibody titers decreased over time, with titers of 770 (316 to 1089) U/mL at 15 days, 385 (203 to 690) U/mL at 30 days, 254 (138 to 423) U/mL at 60 days, and 208 (107 to 375) U/mL at 90 days after the second dose. When an antibody titer of 137 U/mL was assumed to be a measure related to breakthrough infection, the proportion of subjects with antibody titers exceeding this level was 90.1% at 15 days, 85.3% at 30 days, 75.0% at 60 days, and 65.4% at 90 days after the second dose. When a decrease in antibody titers below the assumed breakthrough level was defined as an event, subjects with a pre-dialysis albumin ≥ 3.5 g/dL were significantly less likely to experience an event than subjects with a pre-dialysis albumin < 3.5 g/dL.

Conclusions

The presence of anti-spike protein levels ≥ 313 U/mL at 30 days after the second vaccine dose might be a factor in maintaining enough antibody titers at 90 days after. Whether an additional vaccine dose is needed should be determined based on indicators serving as factors in maintaining antibody titers as well as the status of the spread of infection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07809-1.

Serum NT-proBNP levels and histopathological myocardial fibrosis in autopsied cases from a Japanese community: The Hisayama Study

BACKGROUND

natriuretic peptide is associated with myocardial fibrosis in animal models and among patients with heart disease. However, it remains unclear whether serum N-terminal pro-B-type peptide (NT-proBNP) levels are associated with histopathologically proven myocardial fibrosis among individuals without apparent heart disease. This study aimed to evaluate the association between serum NT-proBNP levels and the histopathologically estimated myocardial fibrotic area in autopsied samples from a community.

METHODS

we selected 63 cases without apparent heart disease with available data of serum NT-proBNP concentrations within six years before death (average age: 82 years; male: 52%) from autopsied cases in a community, and evaluated the percentage areas of myocardial fibrosis in four cardiac segments from each case (i.e. 252 cardiac segments in total). The association between serum NT-proBNP levels and the percentage area of myocardial fibrosis was estimated using a linear mixed model for repeated measures.

RESULTS

serum NT-proBNP levels were positively correlated with myocardial fibrotic area [Pearson's correlation coefficient: r = 0.49 (95% confidence interval: 0.28-0.66), p <0.001]. Serum NT-proBNP levels were significantly associated with the percentage areas of myocardial fibrosis after adjusting for potential confounding factors. There was no evidence of heterogeneity in the association between the subgroups with and without reduced estimated glomerular filtration rate (<60 mL/min/1.73 m²).

CONCLUSIONS

the present study demonstrated that elevated serum NT-proBNP levels were associated with the histopathologically measured myocardial fibrotic area in autopsied cases from a community. These findings may help clarify the association between elevated serum NT-proBNP levels and myocardial fibrosis and their influence on prognosis.

Reduced Estimated GFR and Cardiac Remodeling: A Population-Based Autopsy Study

RATIONALE & OBJECTIVE

Evidence suggests that cardiac remodeling, including left ventricular hypertrophy and myocardial fibrosis, develops with progression of kidney disease. Few studies have examined cardiac pathology across a range of estimated glomerular filtration rates (eGFRs), which was the objective of this investigation.

STUDY DESIGN

Population-based cross-sectional study of deceased patients undergoing autopsy.

SETTING & PARTICIPANTS

334 of 694 consecutive deceased patients undergoing autopsy with available cardiac tissue, with a prior health examination within 6 years and without a prior diagnosis of heart disease.

EXPOSURE

eGFR.

OUTCOMES

The thickness of the left ventricular wall, sizes of cardiac cells, and percentages of fibrosis, estimated from pathology examination of autopsy samples.

ANALYTICAL APPROACH

Generalized estimating equations.

RESULTS

Lower eGFRs were associated with greater left ventricular wall thickness. Deceased patients with eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m² had left ventricular wall thicknesses of 9.1, 9.5, 9.8, and 10.3mm, respectively (P for trend<0.05). Lower eGFRs were also significantly associated with greater mean values of cardiac cell size in the left ventricular wall after adjusting for confounders: 15.3, 16.1, 16.4, and 17.4μm for eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m² (P for trend<0.01). Patients with lower eGFRs had significantly higher multivariable-adjusted geometric mean values for fibrosis percentage in the left ventricular wall: 3.22%, 4.33%, 3.83%, and 6.14% for eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m² (P for trend<0.001). The negative association of eGFR with multivariable-adjusted mean values of cardiac cell width was stronger among patients with than those without anemia.

LIMITATIONS

Cross-sectional study with a high proportion of elderly patients, no available information for severity or duration of hypertension and other cardiovascular risk factors, no information for medication use.

CONCLUSIONS

These findings suggest that reduced eGFR is associated with cardiac hypertrophy and fibrosis of the left ventricle, cardiac cell enlargement, and cardiac fibrosis.

Serum 1,25-dihydroxyvitamin d and the development of kidney dysfunction in a Japanese community

BACKGROUND

 Recent evidence indicates that vitamin D deficiency is associated with an increased risk of renal impairment, but studies addressing the influence of vitamin D deficiency on the development of chronic kidney disease (CKD) in the general Asian population have been few.

METHODS AND RESULTS

 A total of 2,417 community-dwelling individuals without CKD stage 3-5 aged ≥40 years were followed for 5 years (mean age, 60 years; women, 59.1%). The cumulative incidence of CKD stage 3-5, defined as estimated glomerular filtration rate (eGFR) <60ml·min(-1)·1.73m(-2), and the rate of decline in eGFR according to quartile of serum 1,25-dihydroxyvitamin D (1,25(OH)2D), were estimated. During follow-up, 378 subjects experienced CKD stage 3-5. The age- and sex-adjusted incidence of CKD stage 3-5 increased significantly with decreasing serum 1,25(OH)2D (P for trend <0.001). Compared with the highest quartile, the multivariate-adjusted odds ratio for the development of CKD stage 3-5 was 1.90 in the lowest quartile and 1.74 in the second lowest quartile, after adjusting for confounding factors. Additionally, lower serum 1,25(OH)2D was significantly associated with a greater change in eGFR (-0.10ml·min(-1)·1.73m(-2)·year(-1) per 10-pg/ml decrement in serum 1,25(OH)2D).

CONCLUSIONS

 Lower serum 1,25(OH)2D is a significant risk factor for the development of CKD stage 3-5 in the general Asian population.