Treatment outcomes of obstructive sleep apnoea in obese community-dwelling children: the NANOS study

The first line of treatment of obstructive sleep apnoea syndrome (OSAS) in children consists of adenotonsillectomy (T&A). The aim of the present study was to evaluate treatment outcomes of OSAS among obese children recruited from the community.A cross-sectional, prospective, multicentre study of Spanish obese children aged 3–14 years, with four groups available for follow-up: group 1: non-OSAS with no treatment; group 2: dietary treatment; group 3: surgical treatment; and group 4: continuous positive airway pressure treatment.117 obese children (60 boys, 57 girls) with a mean age of 11.3±2.9 years completed the initial (T0) and follow-up (T1)assessments. Their mean body mass index (BMI) at T1was 27.6±4.7 kg·m−2, corresponding to a BMI Z-score of 1.34±0.59. Mean respiratory disturbance index (RDI) at follow-up was 3.3±3.9 events·h−1. Among group 1 children, 21.2% had an RDI ≥3 events·h−1at T1, the latter being present in 50% of group 2, and 43.5% in group 3. In the binary logistic regression model, age emerged as a significant risk factor for residual OSAS (odds ratio 1.49, 95% confidence interval 1.01–2.23; p<0.05) in obese children surgically treated, and RDI at T0as well as an increase in BMI emerged as significant risk factors for persistent OSAS in obese children with dietary treatment (OR 1.82, 95% CI 1.09–3.02 (p<0.03) and OR 8.71, 95% CI 1.24–61.17 (p=0.03)).Age, RDI at diagnosis and obesity are risk factors for relatively unfavourable OSAS treatment outcomes at follow-up.

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Multi-Center Phase II Study of CAMPATH-1H Dose De-Escalation Prior to Nonmyeloablative HLA-Identical Sibling Transplantation.

Blood ◽

10.1182/blood.v110.11.1055.1055 ◽

2007 ◽

Vol 110 (11) ◽

pp. 1055-1055

Author(s):

Ronjon Chakraverty ◽

Nilusha Manji ◽

Richard Clark ◽

Charles Crawley ◽

Peter Johnson ◽

...

Keyword(s):

Total Dose ◽

Chronic Gvhd ◽

Conditioning Regimen ◽

Significant Risk ◽

Post Transplantation ◽

Group 4 ◽

Group 3 ◽

Group 2 ◽

Group 1

Abstract Inclusion of CAMPATH-1H as part of a Fludarabine/Melphalan conditioning regimen is effective at preventing GVHD and reducing non-relapse mortality (NRM)following allogeneic stem cell transplantation. However, these benefits are offset by high rates of infection and potentially a loss of graft-versus-tumor effects. When used at a total dose of 100mg, CAMPATH-1H antibody can still be detected at levels in excess of those required to induce ADCC for several weeks. We reasoned that a reduction in the dose of CAMPATH-1H would permit improved immune reconstitution post-transplantation. We report here the analysis of a national, multi-center trial in which the total dose of CAMPATH-1H was reduced step-wise in separate cohorts from 60mg to 20mg prior to HLA-identical sibling transplantation (n=106). Eligibility criteria included patients with haematological malignancies who were aged 18–65, who had a life expectancy >3 months and who were not suitable for standard myeloablative conditioning. Primary endpoints included PK data, chimerism, NRM and incidence of GVHD or infection. The study received IRB approval and all patients gave informed consent. Four total doses of CAMPATH-1H were tested in consecutive cohorts: group 1, 60mg split between d-2 and d-1 (n=26); group 2, 40mg split between d-2 and d-1 (n=27); group 3, 30mg d-1 (n=28); and group 4, 20mg on day -1 (n=25). 97/106 patients recruited to the study are evaluable with a median follow up of 12 months. Median age was 50 (range 19–64). No major differences were identified in patient characteristics between each cohort. 1-year OS and PFS for the whole population was 80.8% and 67.2% respectively. Peak CAMPATH-IH levels (ug/ml) measured by ELISA on day 0 (n=5 each group) were 7.7 ±1.1 in group 1, 4.3 ±0.7 in group 2, 4.9 ±0.8 in group 3 and 2.7± 0.7 in group 4 (p<0.05 groups 1 vs. each group 2–4). By day 28, CAMPATH-1H levels had fallen substantially in all groups, but especially groups 3/4: 1.1 ±0.4 in group1, 0.6 ±0.1 in group 2, 0.1 ±0.06 in group 3 and 0.1 ±0.06 in group 4 (p<0.05 group 1 vs. each group 3 and 4). In groups 3 and 4, 40% of patients had undetectable CAMPATH-1H levels by day 28. Chimerism data was available in 78 patients and of these, 1 patient showed autologous reconstitution, 52 were mixed chimeras and 25 were full chimeras, with no differences between the groups. Day 100 NRM was 4% in group 1, 8% in group 2, 0% in group 3 and 12% in group 4. Grade III-IV GVHD was 0% in group 1, 4% in group 2, 0% in group 3 and 11% in group 4 (p=0.09 group 1 vs. 4). It is noteworthy that 2 patients in group 4 died of complications secondary to grade IV GVHD, although no patients died of this complication in any of the other cohorts. There were no significant differences in the rates of initial CMV reactivation between the groups, or in the rates of CD4 reconstitution. Cumulative incidences of chronic GVHD at 1-year were 55% and 30% in groups 1 and 2, although further follow up is required in later cohorts. We conclude that significant de-escalation of the CAMPATH-1H dose prior to HLA-identical sibling transplantation is feasible without increasing NRM, although reductions below 30mg are associated with a clinically significant risk of severe acute GVHD. Further studies are warranted to determine whether reductions in CAMPATH-1H dosage will translate into improvements in progression-free survival.

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Continuous Positive Airway Pressure Device Time to Procurement in a Disadvantaged Population

Sleep Disorders ◽

10.1155/2015/747906 ◽

2015 ◽

Vol 2015 ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

Lourdes M. DelRosso ◽

Romy Hoque ◽

Andrew L. Chesson

Keyword(s):

Continuous Positive Airway Pressure ◽

Airway Pressure ◽

Positive Airway Pressure ◽

Apnea Hypopnea Index ◽

Disadvantaged Population ◽

Obstructive Sleep ◽

Group 3 ◽

Group 2 ◽

Group 1

Introduction.The management of obstructive sleep apnea (OSA) in patients who cannot afford a continuous positive airway pressure (CPAP) device is challenging. In this study we compare time to CPAP procurement in three groups of patients diagnosed with OSA: uninsured subsidized by a humanitarian grant (Group 1), uninsured unsubsidized (Group 2), and those with Medicare or Medicaid (Group 3). We evaluate follow-up and adherence in Group 1. We hypothesize that additional factors, rather than just the ability to obtain CPAP, may uniquely affect follow-up and adherence in uninsured patients.Methods.30 patients were in Groups 1 and 2, respectively. 12 patients were in Group 3. Time of CPAP procurement from OSA diagnosis to CPAP initiation was assessed in all groups. CPAP adherence data was collected for Group 1 patients at 1, 3, 6, and 9 months.Results.There were no significant differences between groups in gender, age, body mass index, or apnea hypopnea index. The mean time to procurement in Group 1 was shorter compared to Group 2 but not significant. Compared to both Group 1 and Group 2, Group 3 patients had significantly shorter times to device procurement.Conclusion.Time to procurement of CPAP was significantly shorter in those with Medicaid/Medicare insurance compared to the uninsured.

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Effects of posterior tibial slope on the mid-term results of medial unicompartmental knee arthroplasty

Arthroplasty ◽

10.1186/s42836-021-00070-y ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Zhijie Chen ◽

Kaizhe Chen ◽

Yufei Yan ◽

Jianmin Feng ◽

Yi Wang ◽

...

Keyword(s):

Knee Flexion ◽

Tibial Slope ◽

Posterior Tibial ◽

Significant Difference ◽

Medial Unicompartmental Knee Arthroplasty ◽

Group 3 ◽

Group 2 ◽

Postoperative Knee ◽

Group 1

Abstract Objective To evaluate the effect of medial posterior tibial slope (PTS) on mid-term postoperative range of motion (ROM) and functional improvement of the knee after medial unicompartmental knee arthroplasty (UKA). Methods Medical records of 113 patients who had undergone 124 medial UKAs between April 2009 through April 2014 were reviewed retrospectively. The mean follow-up lasted 7.6 years (range, 6.2–11.2 years). Collected were demographic data, including gender, age, height, weight of the patients. Anteroposterior (AP) and lateral knee radiographs of the operated knees were available in all patients. The knee function was evaluated during office follow-up or hospital stay. Meanwhile, postoperative PTS, ROM, maximal knee flexion and Hospital for Special Surgery (HSS) knee score (pre−/postoperative) of the operated side were measured and assessed. According to the size of the PTS, patients were divided into 3 groups: group 1 (<4°), group 2 (4° ~ 7°) and group 3 (>7°). The association between PTS and the knee function was investigated. Results In our cohort, the average PTS was 2.7° ± 0.6° in group 1, 5.6° ± 0.9° in group 2 and 8.7° ± 1.2° in group 3. Pairwise comparisons showed significant differences among them (p < 0.01). The average maximal flexion range of postoperative knees in each group was 112.4° ± 5.6°, 116.4° ± 7.2°, and 117.5° ± 6.1°, respectively, with significant difference found between group 1 and group 2 (p < 0.05), and between group 1 and group 3 (p < 0.05). However, the gender, age, and body mass index (BMI) did not differ between three groups and there was no significant difference between groups in terms of pre−/postoperative HSS scores or postoperative knee ROM. Conclusion A mid-term follow-up showed that an appropriate PTS (4° ~ 7°) can help improve the postoperative flexion of knee. On the other hand, too small a PTS could lead to limited postoperative knee flexion. Therefore, the PTS less than 4° should be avoided during medial UKA.

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The Relationship between Serum Ferritin Levels and 5-Year All-Cause Mortality in Hemodialysis Patients

Blood Purification ◽

10.1159/000515639 ◽

2021 ◽

pp. 1-7

Author(s):

Emre Erdem ◽

Ahmet Karatas ◽

Tevfik Ecder

Keyword(s):

Serum Ferritin ◽

Hemodialysis Patients ◽

Rank Test ◽

Significant Difference ◽

All Cause Mortality ◽

Group 3 ◽

Group 2 ◽

The Relationship ◽

Group 1

Introduction: The effect of high serum ferritin levels on long-term mortality in hemodialysis patients is unknown. The relationship between serum ferritin levels and 5-year all-cause mortality in hemodialysis patients was investigated in this study. Methods: A total of 173 prevalent hemodialysis patients were included in this study. The patients were followed for up to 5 years and divided into 3 groups according to time-averaged serum ferritin levels (group 1: serum ferritin <800 ng/mL, group 2: serum ferritin 800–1,500 ng/mL, and group 3: serum ferritin >1,500 ng/mL). Along with the serum ferritin levels, other clinical and laboratory variables that may affect mortality were also included in the Cox proportional-hazards regression analysis. Results: Eighty-one (47%) patients died during the 5-year follow-up period. The median follow-up time was 38 (17.5–60) months. The 5-year survival rates of groups 1, 2, and 3 were 44, 64, and 27%, respectively. In group 3, the survival was lower than in groups 1 and 2 (log-rank test, p = 0.002). In group 1, the mortality was significantly lower than in group 3 (HR [95% CI]: 0.16 [0.05–0.49]; p = 0.001). In group 2, the mortality was also lower than in group 3 (HR [95% CI]: 0.32 [0.12–0.88]; p = 0.026). No significant difference in mortality between groups 1 and 2 was found (HR [95% CI]: 0.49 [0.23–1.04]; p = 0.063). Conclusion: Time-averaged serum ferritin levels >1,500 ng/mL in hemodialysis patients are associated with an increased 5-year all-cause mortality risk.

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Etiology of Cartilage Lesions Does Not Affect Clinical Outcomes of Patellofemoral Autologous Chondrocyte Implantation

Cartilage ◽

10.1177/19476035211030991 ◽

2021 ◽

pp. 194760352110309

Author(s):

Alexandre Barbieri Mestriner ◽

Jakob Ackermann ◽

Gergo Merkely ◽

Pedro Henrique Schmidt Alves Ferreira Galvão ◽

Luiz Felipe Morlin Ambra ◽

...

Keyword(s):

Clinical Outcomes ◽

Autologous Chondrocyte Implantation ◽

Second Generation ◽

Cartilage Lesion ◽

Chondrocyte Implantation ◽

Group 3 ◽

Group 2 ◽

Autologous Chondrocyte ◽

Group 1

Objective To determine the relationship between cartilage lesion etiology and clinical outcomes after second-generation autologous chondrocyte implantation (ACI) in the patellofemoral joint (PFJ) with a minimum of 2 years’ follow-up. Methods A retrospective review of all patients that underwent ACI in the PFJ by a single surgeon was performed. Seventy-two patients with a mean follow-up of 4.2 ± 2.0 years were enrolled in this study and were stratified into 3 groups based on the etiology of PFJ cartilage lesions: patellar dislocation (group 1; n = 23); nontraumatic lesions, including chondromalacia, osteochondritis dissecans, and degenerative defects (group 2; n = 28); and other posttraumatic lesions besides patellar dislocations (group 3; n = 21). Patient’s mean age was 29.6 ± 8.7 years. Patients in group 1 were significantly younger (25.4 ± 7.9 years) than group 2 (31.7 ± 9.6 years; P = 0.025) and group 3 (31.5 ± 6.6 years; P = 0.05). Body mass index averaged 26.2 ± 4.3 kg/m2, with a significant difference between group 1 (24.4 ± 3.2 kg/m2) and group 3 (28.7 ± 4.5 kg/m2; P = 0.005). A clinical comparison was established between groups based on patient-reported outcome measures (PROMs) and failure rates. Results Neither pre- nor postoperative PROMs differed between groups ( P > 0.05). No difference was seen in survivorship between groups (95.7% vs. 82.2% vs. 90.5%, P > 0.05). Conclusion Cartilage lesion etiology did not influence clinical outcome in this retrospective study after second generation ACI in the PFJ. Level of Evidence Level III, retrospective comparative study.

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A tissue-engineered urinary conduit in a porcine urinary diversion model

Scientific Reports ◽

10.1038/s41598-021-94613-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Arkadiusz Jundziłł ◽

Piotr Kwieciński ◽

Daria Balcerczyk ◽

Tomasz Kloskowski ◽

Dariusz Grzanka ◽

...

Keyword(s):

Computed Tomography ◽

Urinary Diversion ◽

Porcine Model ◽

Histological Evaluation ◽

Metabolic Complications ◽

Group 3 ◽

Group 2 ◽

The Right ◽

Group 1

AbstractThe use of an ileal segment is a standard method for urinary diversion after radical cystectomy. Unfortunately, utilization of this method can lead to numerous surgical and metabolic complications. This study aimed to assess the tissue-engineered artificial conduit for urinary diversion in a porcine model. Tissue-engineered tubular polypropylene mesh scaffolds were used for the right ureter incontinent urostomy model. Eighteen male pigs were divided into three equal groups: Group 1 (control ureterocutaneostomy), Group 2 (the right ureter-artificial conduit-skin anastomoses), and Group 3 (4 weeks before urostomy reconstruction, the artificial conduit was implanted between abdomen muscles). Follow-up was 6 months. Computed tomography, ultrasound examination, and pyelogram were used to confirm the patency of created diversions. Morphological and histological analyses were used to evaluate the tissue-engineered urinary diversion. All animals survived the experimental procedures and follow-up. The longest average patency was observed in the 3rd Group (15.8 weeks) compared to the 2nd Group (10 weeks) and the 1st Group (5.8 weeks). The implant’s remnants created a retroperitoneal post-inflammation tunnel confirmed by computed tomography and histological evaluation, which constitutes urostomy. The simultaneous urinary diversion using a tissue-engineered scaffold connected directly with the skin is inappropriate for clinical application.

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Evaluation of the TGS TA system for the detection of anti-Toxoplasma antibodies

Microbiologia Medica ◽

10.4081/mm.2017.6583 ◽

2017 ◽

Vol 32 (1) ◽

Author(s):

Olivia Arpino ◽

Annalisa Cianflone ◽

Maria Teresa Manco ◽

Alessia Paganini ◽

Massimo De Paschale ◽

...

Keyword(s):

High Avidity ◽

Past Infection ◽

Recent Infection ◽

Igm Antibodies ◽

Igg Avidity ◽

Avidity Test ◽

Group 3 ◽

Group 2 ◽

Group 1

Background and aims. The aim of the present study was to evaluate the new chemiluminescence TGS TA system of Technogenetics (Milan, Italy) for detecting anti-Toxoplasma IgG and IgM antibodies and IgG avidity. The TGS TA system was compared with our chemiluminescence routinely used system, LIAISON XL, supplied by Diasorin (Saluggia, Italy), for the detection of IgG and IgM antibodies. Only in positive IgM samples (retrospective study) and for the IgG avidity (if existent), TGS TA system was compared to an Enzyme Linked Fluorescent Assay (ELFA) test (VIDAS, BioMérieux, Marcy-l’Étoile, France). Materials and methods. Three hundred and one sera samples, from women who came to our centre for the routine follow up pregnancy, were examined with the TGS TA system and divided in 3 groups according to IgG and IgM screening LIAISON XL tests: 106 were non-immune women (Group 1), 100 were pregnant with past infection (Group 2) and 95 were pregnant with positive or equivocal IgM (82 with positive IgG and 13 with negative IgG) (Group 3). Results. The overall concordance of the IgG results between LIAISON XL and TGS TA was 99.3%: 100% in Group 1, 98% in Group 2 and 100% in Group 3. The overall concordance of the IgM results between LIAISON XL and TGS TA was 93.9%: 100% in Group 1, 94% in Group 2 and 82.8% in Group 3. In Group 3, the concordance between the results of the IgG avidity with the ELFA and TGS TA tests was 81.7%. Comparing the clinical diagnosis obtained with our protocol and that of the TGS TA system, the overall concordance was 92.7%: 100% in Group 1, 92.0% in Group 2 and 78.9% in Group 3. Conclusions. The overall concordance of IgG antibodies is excellent for both protocols while for IgM antibodies is very high in the first group and lower in the third group, due to the presence of non-specific IgM subjects in this group. The TGS TA avidity test seems to predict ealier the maturation of the IgG compared to the ELFA test since many samples with low avidity with the ELFA were seen with moderate avidity with TGS TA and all those with borderline avidity with the ELFA were seen with high avidity with TGS TA. This system shows to be a valuable tool with overall good clinical correlation and able to clearly identify nonspecific subjects, those with a non-recent infection.

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Comparison of Changes in Number of Hyperreflective Dots After İntravitreal Ranibizumab or Dexamethasone İmplant in Patients with Branch Retinal Vein Occlusion

10.21203/rs.3.rs-736656/v1 ◽

2021 ◽

Author(s):

Aylin Karalezli ◽

Sema Kaderli ◽

Ahmet Kaderli ◽

Cansu Kaya ◽

Sabahattin Sul

Keyword(s):

First Year ◽

Intravitreal Ranibizumab ◽

Retinal Layers ◽

Vein Occlusion ◽

Significant Difference ◽

Group 3 ◽

The Mean ◽

Group 2 ◽

Group 1

Abstract Purpose: To compare the effect of intravitreal ranibizumab (IVR) or intravitreal dexamethasone implants (IVD) on regression of hyperreflective dots (HRDs) on optical coherence tomography (OCT) B-scan in patients with branch retinal vein occlusion (BRVO). Methods: 37 eyes of 37 patients with cystoid macular edema who received IVR or IVD and followed up for at least 12 months were included in this study. The patients were divided into three groups according to intravitreal treatment. Group 1 consisted of 12 eyes who received only IVD, group 2 consisted of 10 eyes who received only IVR on a pro re nata and group 3 consisted of 15 eyes who received both IVD and IVR. OCT parameters (CMT, number of HRDs, status of external limiting membrane (ELM) and ellipsoid zone (EZ)) and best-corrected visual acuity (BCVA) were compared between the groups over the follow-up time. HRDs were categorized as HRD in inner retinal layers (from the internal limiting membrane to the inner nuclear layer) or HRD in outer retinal layers (from the outer plexiform layer to the outer border of the photoreceptor layer).Results: There was no significant difference between groups in terms of BCVA, CMT, HRDs in the inner and the outer retinal layers at baseline visit. (p˃0.05 for all) Comparing the baseline values in all groups, a significant decrease was observed in CMT in the first year. (For group 1; p=0.013, group 2; p=0.010; group 3, p<0.001) The BCVA was significantly increased after 1 year in all groups. (p=0.001, p=0.006, p<0.001) The mean number of HRDs in inner and outer retinal layers were significantly decreased in group 1 and group 3. (For group 1; p<0.001, p=0.001, for group 3; p<0.001, p<0.001) However, there was no significant difference in terms of the mean number of HRDs in inner and outer retinal layers for group 2. (p=0.134, p=0.477) At the first year, the number of HRDs in inner and outer retinal layers was significantly lower in group 1 and group 3 than group 2. (For inner HRDs; group 1 vs. group 2 p=0.007, group 2 vs. group 3 p<0.001. For outer HRDs group 1 vs. group 2 p<0.001, group 2 vs. group 3 p<0.001.) The BCVA was higher in group 3 than group 2 at 1year. (p=0.048). There was no significant difference in terms of post-treatment CMT and the number of HRDs between group 1 and group3 in posthoc tests (p=0.621, p=0.876, and p=0.632).Conclusion: The reduction in HRDs at 12 months and better BCVA after IVD intimates that the HRDs should be considered as inflammatory markers in the follow-up of CME in BRVO. Thus, IVD injection could be more appropriate for patients with higher HRDs after BRVO.

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Long-term outcome of endocardial-only versus combined endocardial-epicardial homogenization of the scar for treatment of ventricular tachycardia in patients with ischemic cardiomyopathy

European Heart Journal ◽

10.1093/eurheartj/ehab724.0364 ◽

2021 ◽

Vol 42 (Supplement_1) ◽

Author(s):

S Mohanty ◽

C Trivedi ◽

D G Della Rocca ◽

C Gianni ◽

B MacDonald ◽

...

Keyword(s):

Ventricular Tachycardia ◽

Ischemic Cardiomyopathy ◽

Heart Surgery ◽

Open Heart Surgery ◽

Long Term Outcome ◽

Obstructive Sleep ◽

Number Of Patients ◽

Group 2 ◽

Group 1

Abstract Introduction We investigated the ablation success of scar homogenization with combined (epicardial + endocardial) versus endocardial-only approach for ventricular tachycardia (VT) in patients with ischemic cardiomyopathy (ICM) at 5 years of follow-up. Method Consecutive ICM patients undergoing VT ablation at our center were classified into group 1: endocardial scar homogenization and group 2: endocardial +epicardial scar homogenization. Patients with previous open heart surgery were excluded. All patients underwent bipolar substrate mapping with standard scar settings defined as normal tissue >1.5 mV and severe scar <0.5 mV. Non-inducibility of monomorphic VT was the procedural endpoint in both groups. Patients were followed up twice a year for 5 years with implantable device interrogations. Results A total of 361 (Group 1: 291 and group 2: 70) patients were included in the study (mean age: 67 years, male: 88.4%). At 5 years, significantly higher number of patients from group 2 remained arrhythmia-free (figure 1). Of those patients, 87 (45%) and 51 (89%) from group 1 and 2 respectively were off-anti-arrhythmic drugs (AAD) (p<0.001). After adjusting for age, gender, hypertension, diabetes, and obstructive sleep apnea, scar homogenization using endo-epicardial approach was associated with 51% less recurrence compared to the endocardial ablation strategy (Hazard Ratio: 0.49, 95% CI: 0.27–0.89, p: 0.02). Conclusion In this series of patients with ischemic cardiomyopathy and VT, endo-epicardial scar homogenization was associated with a lower need for AAD and a significantly lower recurrence rate at 5-years of follow-up compared to the endocardial ablation alone. FUNDunding Acknowledgement Type of funding sources: None. Figure 1

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Incidence of Severe Acute Respiratory Syndrome Coronavirus-2 infection among previously infected or vaccinated employees

10.1101/2021.07.03.21259976 ◽

2021 ◽

Author(s):

Noah Kojima ◽

Arash Roshani ◽

Matthew Brobeck ◽

Arthur Baca ◽

Jeffrey D Klausner

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Clinical Laboratory ◽

Exact Equation ◽

Previous Infection ◽

Group 3 ◽

Group 2 ◽

Measure Of Association ◽

Observation Period ◽

Group 1

Introduction: The protective effect of previous infection versus vaccination is poorly studied. Among a clinical laboratory that has been conducting routine workforce screening since the beginning of the pandemic, we aimed to assess the relative risk of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection among individuals who were SARS-CoV-2 naive, previously infected, or vaccinated. Methods: Using an electronic laboratory information system, employees were divided into three groups: (1) SARS-CoV-2 naive and unvaccinated, (2) previous SARS-CoV-2 infection, and (3) vaccinated. Person-days were measured from the date of the employee first test and truncated at the end of the observation period. SARS-CoV-2 infection was defined as two positive SARS-CoV-2 PCR tests in a 30-day period. Individuals with fewer than 14 days of follow up were excluded. Incidence estimates and the 95% confidence intervals were calculated using the Poisson Exact equation. The incidence rate ratio (IRR) was used as a measure of association between groups. Analyses were performed on StataSE (StataCorp, College Station, TX). Results: We identified 4313, 254 and 739 employee records for groups 1, 2, and 3, respectively. The median age of employees was 29.0 years (interquartile range: 23.6, 39.9). During the observation period, 254, 0, and 4 infections were identified among groups 1, 2, and 3, respectively. Group 1 had an incidence of 25.9 per 100 person-years (95% CI: 22.8-29.3). Group 2 had an incidence of 0 per 100 person-years (95% CI: 0-5.0). Group 3 had an incidence of 1.6 per 100 person-years (95% CI: 0.04-4.2). The IRR of reinfection among those with previous infection compared to SARS-CoV-2 naive was 0 (95% CI: 0-0.19). The IRR of those vaccinated compared to SARS-CoV-2 naive was 0.06 (95% CI: 0.02-0.16). The IRR of those vaccinated compared to prior SARS-CoV-2 was 0 (95% CI: 0-4.98). Conclusion: Previous SARS-CoV-2 infection and vaccination for SARS-CoV-2 were associated with decreased risk for infection or re-infection with SARS-CoV-2 in a routinely screened workforce. The was no difference in the infection incidence between vaccinated individuals and individuals with previous infection. Further research is needed to determine whether our results are consistent with the emergence of new SARS-CoV-2 variants.

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