MO914: Development of Antibody Response to SARS-COV-2 Vaccines in Haemodialysis Patients

BACKGROUND AND AIMS

Previous data has shown a reduced immune response shortly after SARS-CoV-2 vaccinations in haemodialysis patients. We therefore investigated the long-term antibody response in patients from different outpatient dialysis centres at 4 weeks and 6 months after a complete vaccination against COVID-19. The results were compared with the humoral responses of non-dialysis subjects.

METHODS

We designed a retrospective multicentric cohort study, enrolling 106 haemodialysis patients and 50 non-dialysis patients after the SARS-CoV-2 vaccination. SARS-CoV-2 antibody testing was performed as part of routine clinical practice 4 weeks as well as 6 months after the immunization with chemiluminescence immunoassays designed to detect antibodies against the SARS-CoV-2 spike protein (Elecsys Anti-SARS-CoV-2 S, Roche Diagnostics, Mannheim, Germany). Testing was performed in the Institute of Laboratory Medicine of the University Hospital Munich. According to the manufacturer's specifications, anti-SARS-CoV-2 S titres >0.8 U/mL are considered reactive (sensitivity 98.8% and specificity 99.9%). Anti-SARS-CoV-2 S titres < 100 U/mL were defined as a low antibody response.

RESULTS

A total of 106 haemodialysis patients with a median age of 73 years received a SARS-CoV-2 vaccination (n = 105 mRNA, n = 1 AstraZeneca). Of these, 50 non-dialysis patients with a median age of 56 years received a SARS-CoV-2 vaccination (n = 45 mRNA, n = 5 mRNA/AstraZeneca). During the observational period, 8 haemodialysis patients and 2 non-dialysis patients additionally contracted a SARS-CoV-2 infection.

Between the two testings, an overall decrease in anti-SARS-CoV-2 S antibody titres was observed (haemodialysis patients from a median of 252 to 95 U/mL, non-dialysis patients from a median of 1621 to 441 U/mL). At 6 months after the complete vaccination, 99 (93%) haemodialysis patients still presented with a detectable anti-SARS-CoV-2 spike antibody response (>0.8 U/mL), comparable to 100% of the non-dialysis subjects. However, 60 (57%) haemodialysis patients showed low antibody response (<100 U/mL), whereas only 5 (10%) non-dialysis patients presented with low antibody response.

Patients with an additional infection showed an increased titre of antibodies during follow-up.

CONCLUSIONS

Our data suggest regular antibody testing as well as a need for booster vaccination in the vulnerable population of haemodialysis patients.

Correlations of UICC tumor stage and tumor regression on T2-weighted MRI sequences during definitive radiotherapy of cervical cancer

BACKGROUND

The purpose of this study is to detect a correlation between the preradiation tumor staging and the relative volumetric regression of the primary tumor through external beam radiation therapy (EBRT).

METHODS

Clinical data of 32 patients with a mean age of 60±12 years treated with primary radiation therapy (RT) of cervical carcinoma were analyzed. Union Internationale Contre le Cancer (UICC) stages were T1 = 4 patients, T2 = 15 patients, T3 = 8 patients, T4 = 5 patients; N1 = 26 patients, N0 = 6 patients; and M0 = 25 patients, M1 = 7 patients. All patients received pelvic magnetic resonance imaging (MRI) before RT as well as during RT. The cervical primary tumor was delineated as gross tumor volume (ptGTV) in T2-weighted MRI sequences. We compared ptGTV reduction by stage, lymph node status, metastatic status, and grading.

RESULTS

Mean ptGTV reduction during RT was 61.4±28.9%. T1 tumors shrank by 88.2±13.4%, T2 by 67.6±28.7%, T3 by 50.8±23.6%, and T4 by 38.7±27.2%. The difference in tumor shrinkage was statistically significant between the lower T stages and the higher T stages (p < 0.05). There was no statistical difference in the mean ptGTV before treatment in the group with lymph node metastases (LNM) (54.1±47.7 cm³) as compared to the group without LNM (76.6±52.2 cm³). Nonetheless, ptGTV shrank significantly differently: by 68.9±25.7% (N1 patients) and by 29.0±17.7% (N0 patients). No significant differences in ptGTV shrinkage were observed in M0 versus M1 and G2 versus G3 tumors.

CONCLUSION

There is a correlation between mean ptGTV reduction during EBRT and tumor stages. Tumors with higher T stages shrank less under radiation treatment, and the ptGTV of N1 patients responded better than that of N0 patients.

Overestimation of Risk and Increased Fear of Long-term Complications of Diabetes in People with Type 1 and 2 Diabetes

Objective The quality report of the disease management programmes of North Rhine Westphalia 2016 showed prevalences for long-term complications (neuropathy, nephropathy, retinopathy) of less than 30% for people with diabetes type 1 (DM1) and type 2 (DM2). The aim of this study was to assess risk expectations and fear regarding long-term complications of diabetes in people with DM1 and DM2.

Methods We assessed risk expectations and fear regarding diabetes complications in people with DM1 (n=110) and DM2 (n=143 without insulin, n=249 with insulin) visiting an University outpatient department of metabolic diseases. Fear of long-term complications was measured with the “Fear of Complications Questionnaire (FCQ)” (range 0–45 points, scores ≥30 suggest elevated fear). Participants were asked to estimate general and personal risks of long-term complications 10 years after developing diabetes in %.

Results Elevated fear of complications (FCQ scores ≥30) was observed in 34.5, 25.9, and 43.0% of those with DM1, DM2 without insulin and DM2 with insulin, respectively. Participants estimated a mean general risk of diabetes-related complications after 10 years amounting to 45.9±15.8% (DM1), 49.7±15.4% (DM2 without insulin), and 52.5±16.4% (DM2 with insulin) and personal risk with 52.5±24.4% (DM1), 45.8±22.7% (DM2 without insulin), and 54.1±23.4% (DM2 with insulin), respectively. Higher risk expectations were associated with higher fear of complications (p<0.001).

Conclusion Risk estimations regarding long-term complications were exaggerated in people with DM1 and DM2. About one third of the participants reported elevated fear of complications. Participants’ risk expectations and fear regarding diabetes complications appear excessive compared to population-based prevalence rates.