Multiple myeloma (MM) patients have increased risk of severe coronavirus disease 2019 (COVID-19) when infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Monoclonal gammopathy of undetermined significance (MGUS), the precursor of MM has been associated with immune dysfunction which may lead to severe COVID-19. No systematic data have been published on COVID-19 in individuals with MGUS. We conducted a large population-based cohort study evaluating the risk of SARS-CoV-2 infection and severe COVID-19 among individuals with MGUS. We included 75,422 Icelanders born before 1976, who had been screened for MGUS in the Iceland Screens Treats or Prevents Multiple Myeloma study (iStopMM). Data on SARS-CoV-2 testing and COVID-19 severity were acquired from the Icelandic COVID-19 Study Group. Using a test-negative study design, we included 32,047 iStopMM participants who had been tested for SARS-CoV-2, of whom 1754 had MGUS. Among these participants, 1100 participants, tested positive, 65 of whom had MGUS. Severe COVID-19 developed in 230 participants, including 16 with MGUS. MGUS was not associated with SARS-CoV-2 infection (Odds ratio (OR): 1.05; 95% confidence interval (CI): 0.81–1.36; p = 0.72) or severe COVID-19 (OR: 0.99; 95%CI: 0.52–1.91; p = 0.99). These findings indicate that MGUS does not affect the susceptibility to SARS-CoV-2 or the severity of COVID-19.

Background Cardiomyopathy is a known complication of organic acidemias but generally thought to be secondary to poor metabolic control. Methods Our patient was found through biochemical testing and Sanger sequencing to harbor an Icelandic founder mutation: NM_052845.4(MMAB):c.571C > T(p.Arg191Trp), leading to an early presentation (4 h after birth) of cblB‐type methylmalonic acidemia (MMA). Biochemical testing of this patient suggested B‐12‐responsiveness and thus the patient was treated with cyanocobalamin throughout life. Informed parental consent was obtained for this report. Results Our patient had three metabolic decompensations in her life (at birth, at 1 month, and at 5 months). The first decompensation was probably linked to stress of delivery, second to rhinovirus infection, and third by co‐infection of norovirus and enterovirus. At 3 months, the patient was noted to be tachypneic, although this was attributed to her underlying metabolic acidosis. At 5 months and 10 days, the patient was admitted with minor flu‐like symptoms but developed severe diarrhea in hospital and upon rehydration had cardiac decompensation and was found to have undiagnosed dilated cardiomyopathy. Although, patient was treated aggressively with dextrose, hemodialysis, levocarnitine, and vasoactive agents, there was limited response to medications to treat cardiac failure, and eventually the patient passed away before turning 6 months old. Conclusions Other than these three mild decompensations, patient had very good metabolic control, thus demonstrating that even without frequent metabolic decompensation, cardiomyopathy can be an observed phenotype in cblB‐type MMA even very early in life, suggesting that this phenotype may be independent of metabolic control.

Background The severity of SARS-CoV-2 infection varies from asymptomatic state to severe respiratory failure and the clinical course is difficult to predict. The aim of the study was to develop a prognostic model to predict the severity of COVID-19 in unvaccinated adults at the time of diagnosis. Methods All SARS-CoV-2-positive adults in Iceland were prospectively enrolled into a telehealth service at diagnosis. A multivariable proportional-odds logistic regression model was derived from information obtained during the enrollment interview of those diagnosed between February 27 and December 31, 2020 who met the inclusion criteria. Outcomes were defined on an ordinal scale: (1) no need for escalation of care during follow-up; (2) need for urgent care visit; (3) hospitalization; and (4) admission to intensive care unit (ICU) or death. Missing data were multiply imputed using chained equations and the model was internally validated using bootstrapping techniques. Decision curve analysis was performed. Results The prognostic model was derived from 4756 SARS-CoV-2-positive persons. In total, 375 (7.9%) only required urgent care visits, 188 (4.0%) were hospitalized and 50 (1.1%) were either admitted to ICU or died due to complications of COVID-19. The model included age, sex, body mass index (BMI), current smoking, underlying conditions, and symptoms and clinical severity score at enrollment. On internal validation, the optimism-corrected Nagelkerke’s R2 was 23.4% (95%CI, 22.7–24.2), the C-statistic was 0.793 (95%CI, 0.789-0.797) and the calibration slope was 0.97 (95%CI, 0.96–0.98). Outcome-specific indices were for urgent care visit or worse (calibration intercept -0.04 [95%CI, -0.06 to -0.02], Emax 0.014 [95%CI, 0.008–0.020]), hospitalization or worse (calibration intercept -0.06 [95%CI, -0.12 to -0.03], Emax 0.018 [95%CI, 0.010–0.027]), and ICU admission or death (calibration intercept -0.10 [95%CI, -0.15 to -0.04] and Emax 0.027 [95%CI, 0.013–0.041]). Conclusion Our prognostic model can accurately predict the later need for urgent outpatient evaluation, hospitalization, and ICU admission and death among unvaccinated SARS-CoV-2-positive adults in the general population at the time of diagnosis, using information obtained by telephone interview.

Background: The severity of SARS-CoV-2 infection varies from asymptomatic state to severe respiratory failure and the clinical course is difficult to predict. The aim of the study was to develop a prognostic model to predict the severity of COVID-19 at the time of diagnosis and determine risk factors for severe disease. Methods: All SARS-CoV-2-positive adults in Iceland were prospectively enrolled into a telehealth service at diagnosis. A multivariable proportional-odds logistic regression model was derived from information obtained during the enrollment interview with those diagnosed before May 1, 2020 and validated in those diagnosed between May 1 and December 31, 2020. Outcomes were defined on an ordinal scale; no need for escalation of care during follow-up, need for outpatient visit, hospitalization, and admission to intensive care unit (ICU) or death. Risk factors were summarized as odds ratios (OR) adjusted for confounders identified by a directed acyclic graph. Results: The prognostic model was derived from and validated in 1,625 and 3,131 individuals, respectively. In total, 375 (7.9%) only required outpatient visits, 188 (4.0%) were hospitalized and 50 (1.1%) were either admitted to ICU or died due to complications of COVID-19. The model included age, sex, body mass index (BMI), current smoking, underlying conditions, and symptoms and clinical severity score at enrollment. Discrimination and calibration were excellent for outpatient visit or worse (C-statistic 0.75, calibration intercept 0.04 and slope 0.93) and hospitalization or worse (C-statistic 0.81, calibration intercept 0.16 and slope 1.03). Age was the strongest risk factor for adverse outcomes with OR of 75- compared to 45- year-olds, ranging from 5.29-17.3. Higher BMI consistently increased the risk and chronic obstructive pulmonary disease and chronic kidney disease correlated with worse outcomes. Conclusion: Our prognostic model can accurately predict the outcome of SARS-CoV-2 infection using information that is available at the time of diagnosis.

Introduction Multiple myeloma (MM) patients have an increased risk of severe coronavirus disease 2019 (COVID-19) when infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Monoclonal gammopathy of undetermined significance (MGUS) precedes MM and related disorders and affects 4.2% of the general population over the age of 50 years. MM and MGUS are associated with immune dysfunction that is believed to contribute to the development of severe COVID-19. Currently, no systematic data on MGUS and COVID-19 have been published. We conducted a large population-based cohort study to evaluate whether MGUS was associated with SARS-CoV-2 infection and the development of severe COVID-19. Methods Data on all SARS-CoV-2 test results and COVID-19 severity was acquired from the COVID-19 Outpatient Clinic at Landspitali - The National University Hospital of Iceland. The first case of COVID-19 in Iceland was diagnosed on February 28 th, 2020. Since then, the Icelandic authorities have followed an aggressive strategy of SARS-CoV-2 testing and contact tracing. All SARS-CoV-2-positive individuals were immediately contacted and those with active infection were enrolled into telehealth monitoring consisting of repeated standardized interviews conducted by a nurse or physician. If clinical deterioration was detected, patients were assessed in person at the COVID-19 Outpatient Clinic and admitted if needed. Study participants were included from the Iceland Screens Treats or Prevents Multiple Myeloma study (iStopMM). The study is an ongoing population-based screening study for MGUS and randomized trial of follow-up strategies. Out of the 148,708 Icelanders who were born 1976 and earlier and were alive on September 9 th 2016, 80,759 (54%) provided informed consent for study participation and 75,422 (94%) of those provided a blood sample for MGUS screening by serum protein electrophoresis (SPEP) and free light chain (FLC) assay. MGUS was determined by current criteria using SPEP and FLC assay data. Individuals who had died, been diagnosed with MM and related disorders, or were undergoing treatment for smoldering MM prior to February 28 th were excluded. First, the association of MGUS and testing positive for SARS-CoV-2 was evaluated. We used a test negative design and included participants who had been tested at least once for SARS-CoV-2 between February 28 th and December 31 st, 2020. The association of MGUS and a positive test for SARS-CoV-2 was assessed using logistic regression, adjusted for sex and age. Next, the association of MGUS and severe COVID-19 was evaluated. Those who tested positive for SARS-CoV-2 were included unless they were hospitalized or living in a nursing home at diagnosis. Participants were followed until discharge from telehealth monitoring or until considered having severe COVID-19. Severe COVID-19 was defined as the composite outcome of the need for outpatient visit or hospital admission and death and as the composite outcome of hospital admission and death. Logistic regression was then performed adjusting for sex and age. Results Of the 75,422 individuals screened for MGUS, 32,047 (42%) were tested for SARS-CoV-2 during the study period of whom 1,754 had MGUS (5.5%). Those with MGUS were older (mean age 66.3 vs 59.1 p<0.001) and more likely to be male (50% vs 41% p<0.001). In total, 1,100 (3.4%) of the participants tested positive for SARS-CoV-2 of whom 65 had MGUS. After adjusting for sex and age, MGUS was not found to be associated with testing positive for SARS-CoV-2 (odds ratio (OR): 1.05; 95% confidence interval (CI): 0.81-1.36; p=0.72; Table; Figure A). Of those who tested positive for SARS-CoV-2, a total of 230 had the composite outcome of requiring an outpatient visit or hospital admission, and death, and 117 had the composite outcome of hospital admission and death. After adjusting for age and sex, MGUS was not found to be associated with either endpoint (OR: 0.99; 95%CI: 0.52-1.91; p=0.99 and OR: 1.13; 95%CI: 0.52-2.46; p=0.76; Table; Figure B) Conclusions: In this large population-based study that included 75,422 individuals screened for MGUS, we did not find MGUS to be associated with SARS-CoV-2 susceptibility or COVID-19 severity. This is contrary to MM which is preceded by MGUS. These findings suggest that immunosuppression in MGUS differs significantly from that of MM and are important since they can inform management and recommendations for individuals with MGUS. Figure 1 Figure 1. Disclosures Kampanis: The Binding Site: Current Employment. Hultcrantz: Intellisphere LLC: Consultancy; Daiichi Sankyo: Research Funding; Curio Science LLC: Consultancy; Amgen: Research Funding; GlaxoSmithKline: Membership on an entity's Board of Directors or advisory committees, Research Funding. Durie: Amgen, Celgene/Bristol-Myers Squibb, Janssen, and Takeda: Consultancy; Amgen: Other: fees from non-CME/CE services . Harding: The Binding Site: Current Employment, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties. Landgren: Amgen: Honoraria; Janssen: Honoraria; Celgene: Research Funding; Janssen: Other: IDMC; Janssen: Research Funding; Takeda: Other: IDMC; Amgen: Research Funding; GSK: Honoraria. Kristinsson: Amgen: Research Funding; Celgene: Research Funding.