Real-world outcomes upon second-line treatment in patients with chronic lymphocytic leukaemia.

For chronic lymphocytic leukaemia (CLL), targeted drugs have become the standard of care, in particular for second-line treatment. In this study, overall survival (OS), treatment-free survival (TFS) and adverse events (AE) were registered retrospectively in a Danish population-based cohort upon second-line treatment for CLL. Data were collected from medical records and the Danish National CLL register. For 286 patients receiving second-line treatment, three-year TFS was higher upon targeted treatment (ibrutinib/venetoclax/idelalisib) [63%, 95% confidence interval (CI) 50%-76%] compared with fludarabine, cyclophosphamide and rituximab or bendamustine and rituximab (FCR/BR) (37%, CI: 26%-48%) and chlorambucil+/-CD20-antibody (CD20Clb/Clb) (22%, CI: 10%-33%). Upon targeted treatment, three-year OS estimates were higher for targeted treatment (79%, CI: 68%-91%) compared with FCR/BR (70%, CI: 60%-81%) or CD20Clb/Clb (60%, CI: 47%-74%). The most common AEs were infections and haematological AEs; 92% of patients treated with targeted drugs had AEs, 53% of which were severe. Upon FCR/BR and CD20Clb/Clb, AEs were present for 75% and 53% respectively, of which 63% and 31% were severe. These real-world data demonstrate higher TFS and a tendency towards higher OS following targeted second-line treatment for CLL compared to chemoimmunotherapy, also for patients who may be frailer and more comorbid.

Impact of type 2 diabetes on mortality, cause of death, and treatment in chronic lymphocytic leukemia.

Age-related comorbid conditions are exceedingly common in patients with chronic lymphocytic leukemia (CLL). As the prevalence of type 2 diabetes (T2D) is predicted to double during the next two decades, a better understanding of the interplay between CLL and T2D is of increasing importance. In this study, analyses were performed in parallel in two separate cohorts, based on Danish national registers and the Mayo Clinic CLL Resource. The primary outcomes were overall survival (OS) from time of CLL diagnosis, OS from time of treatment, and time to first treatment (TTFT), studied using Cox proportional hazard regression analysis and Fine-Gray regression analysis. In the Danish CLL cohort, the prevalence of T2D was 11%, in the Mayo CLL cohort, it was 12%. Patients with CLL and T2D had shorter OS both from time of diagnosis and from first-line treatment for were less likely to receive treatment for CLL compared with patients with CLL and without T2D. The increased mortality was largely driven by an increased risk of death due to infections, especially in the Danish cohort. The findings of this study emphasize a substantial subgroup of CLL patients with co-occurring T2D with an inferior prognosis and a possible unmet treatment need requiring additional interventions and further research.

Increased incidence rates of positive blood cultures shortly after chemotherapy compared to radiotherapy among individuals treated for solid malignant tumours.

BACKGROUND: Cancer treatments suppress immune function and are associated with increased risk of infections, but the overall burden of serious infectious diseases in treated patients has not been clearly elucidated. METHODS: All patients treated for solid malignant tumours with radiotherapy (RT) and/or standard first-line chemotherapy (C) at the Department of Oncology at Rigshospitalet between 01/1/2010 and 31/12/2016 were included. Patients were followed from treatment initiation until the first of new cancer treatment, 1 year after treatment initiation, end of follow-up or death. Incidence rates (IR) of positive blood culture (PBC) per 1000 person-years follow-up (PYFU) were calculated. FINDINGS: 12,433 individuals were included, 3582 (29%), 6349 (51%), and 2502 (20%) treated with RT, C, or both RT & C, respectively, contributing 8182 PYFU. 429 (3%) individuals experienced 502 unique episodes of PBC, incidence rate (95% CI) 52.43 (47.7, 57.6) per 1000 PYFU. The 30-day mortality rate after PBC was 24% independent of treatment modality. Adjusted incidence rate ratios in the first 3 months (95% CI) after PBC significantly varied by treatment: 2.89 (1.83, 4.55) and 2.52 (1.53, 4.14) for C and RT & C compared to RT. Escherichia coli (n = 127, 25%) was the top microorganism identified. INTERPRETATION: PBCs are not common, but when they occur, mortality is high.

Vaccine effectiveness against SARS-CoV-2 reinfection during periods of Alpha, Delta, or Omicron dominance: A Danish nationwide study.

BACKGROUND: Individuals with a prior Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection have a moderate to high degree of protection against reinfection, though seemingly less so when the Omicron variant of SARS-CoV-2 started to circulate. The aim of this study was to evaluate the vaccine effectiveness (VE) against SARS-CoV-2 reinfection, Coronavirus Disease 2019 (COVID-19)-related hospitalization, and COVID-19-related death, in individuals with prior SARS-CoV-2 infection, and to assess the effect of time since vaccination during periods with different dominant SARS-CoV-2 variants. METHODS AND FINDINGS: This study used a nationwide cohort design including all individuals with a confirmed SARS-CoV-2 infection, who were alive, and residing in Denmark between 1 January 2020 and 31 January 2022. Using Danish nationwide registries, we obtained information on SARS-CoV-2 infections, COVID-19 vaccination, age, sex, comorbidity, staying at hospital, and country of origin. The study population included were individuals with prior SARS-CoV-2 infection. Estimates of VE against SARS-CoV-2 reinfection with 95% confidence intervals (CIs) were calculated using a Poisson regression model and adjusted for age, sex, country of origin, comorbidity, staying at hospital, calendar time, and test incidence using a Cox regression model. The VE estimates were calculated separately for three periods with different dominant SARS-CoV-2 variants (Alpha (B.1.1.7), Delta (B.1.617.2), or Omicron (B.1.1.529)) and by time since vaccination using unvaccinated as the reference. In total, 148,527 person-years and 44,192 SARS-CoV-2 infections were included for the analysis regarding reinfections. The study population comprised of 209,814 individuals infected before or during the Alpha period, 292,978 before or during the Delta period, and 245,530 before or during the Omicron period. Of these, 40,281 individuals had completed their primary vaccination series during the Alpha period (19.2%), 190,026 during the Delta period (64.9%), and 158,563 during the Omicron period (64.6%). VE against reinfection following any COVID-19 vaccine type administered in Denmark, peaked at 71% (95% CI: -Inf to 100%) at 104 days or more after vaccination during the Alpha period, 94% (95% CI: 92% to 96%) 14 to 43 days after vaccination during the Delta period, and 60% (95% CI: 58% to 62%) 14 to 43 days after vaccination during the Omicron period. Waning immunity following vaccination was observed and was most pronounced during the Omicron period. Due to too few events, it was not possible to estimate VE for hospitalization and death. Study limitations include potentially undetected reinfections, differences in health-seeking behavior, or risk behavior between the compared groups. CONCLUSIONS: This study shows that in previously infected individuals, completing a primary vaccination series was associated with a significant protection against SARS-CoV-2 reinfection compared with no vaccination. Even though vaccination seems to protect to a lesser degree against reinfection with the Omicron variant, these findings are of public health relevance as they show that previously infected individuals still benefit from COVID-19 vaccination in all three variant periods.

Differences and Temporal Changes in Risk of Invasive Pneumococcal Disease in Adults with Hematological Malignancies: Results from a Nationwide 16-Year Cohort Study.

BACKGROUND: Patients with hematological malignancies (HM) are known to carry an increased risk of invasive pneumococcal disease (IPD). However, temporal variations in IPD risks following a cancer diagnosis remain poorly characterized. To inform vaccine guidelines and patient management, we assessed the IPD incidence among patients with HM and other malignancies. METHODS: The study population included all individuals aged ≥15 years during 2000-2016 in Denmark. Variations in incidences of IPD over time and between different types of hematological malignancies and diagnoses were assessed by Poisson regression. RESULTS: During 85 002 224 person-years of observation, 13 332 episodes of a first IPD were observed, of which 765 (5.7%) occurred among individuals with HM. Among HM patients, the IPD incidence rate decreased continuously during the study period (rate ratio per year, 0.91; 95% confidence interval, .90-.92). The risk of IPD in patients with HM was up to 39 times higher when compared to the background population and was highest for multiple myeloma, acute lymphoblastic leukemia, and chronic lymphocytic leukemia. Unlike other malignancies, the increased IPD risk did not wane with the time since HM diagnosis. We found a vaccination uptake of only ≤2% in patients with HM and ≤1% for those with other types of malignancies. CONCLUSIONS: Adults with HM in general and patients with lymphoid malignancies in particular have an increased risk for IPD, compared with patients with other types of cancer and with individuals free of cancer. The pneumococcal vaccination uptake is extremely low in this at risk-population. Efforts to prevent IPD in HM patients are continuously warranted.

Twenty-five years of triptans - a nationwide population study.

BACKGROUND: The efficacy of triptans as the main acute treatment strategy for migraine headache at the population-wide level needs to be understood to inform clinical decision-making. We summarise key trends in triptan use using more than 25 years of Danish nationwide data. METHODS: We conducted a nationwide register-based cohort study based on all Danish residents with access to public healthcare between 1 January 1994 and 31 October 2019 and summarise informative trends of all purchases of triptans in Denmark in the same period. Complete purchase records of Sumatriptan, Naratriptan, Zolmitriptan, Rizatriptan, Almotriptan, Eletriptan, and Frovatriptan were used. FINDINGS: Over a 25-year period, triptan use increased from 345 to 945 defined daily doses (DDD) per 1000 inhabitants per year and the yearly prevalence of triptan use increased from 5.17 to 14.57 per 1000 inhabitants. Between 2014 and 2019, 12.3% of the Danish migraine population purchased a triptan. Following their initial purchase, 43% of patients had not repurchased triptans within 5 years. At most, 10% of patients indicating triptan discontinuation tried more than one triptan. The prevalence of triptan overuse, defined as having purchased at least 20 DDDs of triptans per month for 3 consecutive months, increased in parallel with the prevalence of triptan use, prevalent in 56 of every 1000 triptan users every year between 2014 and 2019. INTERPRETATION: In a cohort with access to free clinical consultations and low medication costs, we observed low rates of triptan adherence, likely due to disappointing efficacy and/or unpleasant side effects rather than economic considerations. Triptan success continues to be hindered by poor implementation of clinical guidelines and high rates of treatment discontinuance.

Real-world outcomes for 205 patients with chronic lymphocytic leukemia treated with ibrutinib.

Ibrutinib has now been approved for treatment of chronic lymphocytic leukemia (CLL) in both front-line setting and as later-line treatment. However, knowledge about the outcomes and adverse events (AE) among patients at a population-based level is still limited. OBJECTIVES: To report outcomes and AEs in a population-based cohort treated with ibrutinib outside clinical trials. METHODS: We conducted a multicenter, retrospective cohort study including all patients with CLL treated with ibrutinib. RESULTS: In total, 205 patients were included of whom 39 (19%) were treatment-naïve. The median follow-up was 21.4 months (interquartile range (IQR), 11.9,32.8), the estimated overall survival at 12 months was 88.8% (95% confidence interval (CI); 84.3%, 93.3%), and the estimated progression-free survival at 12 months was 86.3% (95% CI; 81.3%, 91.2%). During follow-up, 200 (97.6%) patients had at least one AE and 100 (48.8%) patients had at least one grade ≥3 AE. Eighty-six patients (42.0%) discontinued ibrutinib, hereof 47 (54.7%) due to AEs and 19 (22.1%) had progression of CLL or Richter transformation. CONCLUSIONS: In our study, we find comparable, though slightly inferior, overall, and progression-free survival, and discontinuation due to toxicity was higher compared with clinical trials. Patient training and information may improve treatment adherence outside clinical trials.

Long-term clinical outcomes of patients with hematologically unexplained cytopenia after routine assessment: A single center study.

OBJECTIVE: We investigated mortality and long-term development of malignant hematological disease, cancer, liver-, renal-, and rheumatic disease in patients with unexplained cytopenia (UC). METHODS: We screened all patients referred to the outpatient clinic at the Department of Hematology, Rigshospitalet, Copenhagen, with a suspected myeloid neoplasm from June 2009 to the end of 2012. Through registry linkage, we obtained information on hospital-based ICD-10 diagnoses and survival. We estimated cumulative incidences of disease and hazard ratios of all-cause mortality using the Aalen-Johansen estimator and Cox regression. We compared incidences and mortality with a control cohort. RESULTS: Among 1820 referrals, 221 had UC. The UC group had a 5-year cumulative incidence of malignant hematological disease of 8.91% (CI 95%: 4.98-12.84) compared to 0.93(CI 95%: 0.32-1.55) in the matched controls. In addition, UC patients had higher incidences of cancer, liver, and rheumatic disease. Mortality was higher in UC patients compared to the matched controls with a HR of 1.43 [P = 0.038, CI 95%: 1.02-2.00] adjusted for comorbidity, sex, and age. Most of the mortality and morbidity were ascribed to patients 50 years or older. CONCLUSIONS: Unexplained cytopenia patients had a higher incidence of malignant hematological-, cancer-, liver-, and rheumatic disease and increased mortality compared to the general population.

Myeloproliferative Neoplasms in Danish Twins.

OBJECTIVE: Myeloproliferative neoplasms (MPNs) are a heterogeneous group of diseases characterized by clonal hyperproliferation of immature and mature cells of the myeloid lineage. Genetic differences have been proposed to play a role in the development of MPNs. Monozygotic twin pairs with MPNs have been reported in a few case reports, but the MPN concordance pattern in twins remains unknown. METHOD: All twin pairs born in the period 1900-2010 were identified in the nationwide Danish Twin Registry. Only pairs with both twins alive on January 1, 1977, and those born thereafter were included to allow identification in the Danish National Patient Registry. RESULTS: A total of 158 twin pairs were registered with an MPN diagnosis: 36 monozygotic, 104 dizygotic, and 18 pairs with unknown zygosity. MPNs were diagnosed in both twins in 4 pairs. The probandwise concordance rates for monozygotic twin pairs were higher than for dizygotic twin pairs (15 vs. 0%; p = 0.016). CONCLUSION: An estimated concordance rate of 15% (95% CI 0.059-0.31) is modest, but given the rarity of MPNs this finding is clinically relevant and provides further support for the role of genetic predisposition in the development of MPNs.

Association Between First-time Neurologic Events and Metronidazole Treatment: A Case-time Control Study.

PURPOSE: Metronidazole, a widely used antimicrobial medication, has been linked to neurologic adverse drug reactions. This study investigates the association between metronidazole use and first-time neurologic events. METHODS: We conducted a case-time-control study using data from the Danish National Patient Register and the National Prescription Register in years 2013 to 2021. Patients with a first-time diagnosis of encephalopathy, cerebellar dysfunction, or peripheral neuropathy were included. Conditional logistic regression analyses were performed to estimate the risk of neurologic events associated with metronidazole use. FINDINGS: Out of 476,066 first-time metronidazole prescriptions, the 100-day cumulative incidence of peripheral neuropathy was 0.016%, and 0.002% for cerebellar dysfunction or encephalopathy. In the case-time control study, we identified 17,667 persons with a first-time neurologic event and were included for the analysis. The estimated odds ratio for the combined neurologic events was 0.98 (95% CI, 0.59-1.64, P = 0.95) with no statistically significant association across different subgroups and time windows. IMPLICATIONS: Our findings suggest that metronidazole-induced neurologic events may be rarer than previously described, and we did not find any consistent or statistically significant association between metronidazole exposure. Nonetheless, clinicians should remain vigilant to potential neurologic risks in patients receiving metronidazole, to ensure its safe and effective use.

Erratum: Author Correction: Early stimulated immune responses predict clinical disease severity in hospitalized COVID-19 patients.

[This corrects the article DOI: 10.1038/s43856-022-00178-5.].

Pre-diagnostic trajectories of lymphocytosis predict time to treatment and death in patients with chronic lymphocytic leukemia.

Background: The dynamics of pre-diagnostic lymphocytosis in patients with ensuing chronic lymphocytic leukemia (CLL) need to be explored as a better understanding of disease progression may improve treatment options and even lead to disease avoidance approaches. Our aim was to investigate the development of lymphocytosis prior to diagnosis in a population-based cohort of patients with CLL and to assess the prognostic information in these pre-diagnostic measurements. Methods: All patients diagnosed with CLL in the Greater Copenhagen area between 2008 and 2016 were included in the study. Pre-diagnostic blood test results were obtained from the Copenhagen Primary Care Laboratory Database encompassing all blood tests requested by Copenhagen general practitioners. Using pre-diagnostic measurements, we developed a model to assess the prognosis following diagnosis. Our model accounts for known prognostic factors and corresponds to lymphocyte dynamics after diagnosis. Results: We explore trajectories of lymphocytosis, associated with known recurrent mutations. We show that the pre-diagnostic trajectories are an independent predictor of time to treatment. The implementation of pre-diagnostic lymphocytosis slope groups improved the model predictions (compared to CLL-IPI alone) for treatment throughout the period. The model can manage the heterogeneous data that are to be expected from the real-world setting and adds further prognostic information. Conclusions: Our findings further knowledge of the development of CLL and may eventually make prophylactic measures possible.

Early stimulated immune responses predict clinical disease severity in hospitalized COVID-19 patients.

Background: The immune pathogenesis underlying the diverse clinical course of COVID-19 is poorly understood. Currently, there is an unmet need in daily clinical practice for early biomarkers and improved risk stratification tools to help identify and monitor COVID-19 patients at risk of severe disease. Methods: We performed longitudinal assessment of stimulated immune responses in 30 patients hospitalized with COVID-19. We used the TruCulture whole-blood ligand-stimulation assay applying standardized stimuli to activate distinct immune pathways, allowing quantification of cytokine responses. We further characterized immune cell subsets by flow cytometry and used this deep immunophenotyping data to map the course of clinical disease within and between patients. Results: Here we demonstrate impairments in innate immune response pathways at time of COVID-19 hospitalization that are associated with the development of severe disease. We show that these impairments are transient in those discharged from hospital, as illustrated by functional and cellular immune reconstitution. Specifically, we identify lower levels of LPS-stimulated IL-1ß, and R848-stimulated IL-12 and IL-17A, at hospital admission to be significantly associated with increasing COVID-19 disease severity during hospitalization. Furthermore, we propose a stimulated immune response signature for predicting risk of developing severe or critical COVID-19 disease at time of hospitalization, to validate in larger cohorts. Conclusions: We identify early impairments in innate immune responses that are associated with subsequent COVID-19 disease severity. Our findings provide basis for early identification of patients at risk of severe disease which may have significant implications for the early management of patients hospitalized with COVID-19.

Antimicrobial use before chronic lymphocytic leukemia: a retrospective cohort study.

Chronic lymphocytic leukemia (CLL) is accompanied by increased risk of potentially fatal infections. While this can mostly be attributed to disease-related immune dysfunction, it is not known if CLL patients are also constitutionally susceptible to infections. We linked nation-wide Danish registers to explore this possibility, approximating infection susceptibility by use of antimicrobials. We assessed the incidence of antimicrobials among CLL patients and matched controls from the general population for up to 22 years before index diagnosis, and among children and grandchildren of CLL patients and their matched controls. Our analyses showed that for CLL patients overall antimicrobial use began to increase gradually six years before leukemia diagnosis. Before this time point, CLL patients had used significantly more macrolides (relative risk = 1.15; 95% confidence interval 1.10-1.20), antimycotics (1.18; 1.08-1.30), and antivirals (1.62; 1.45-1.81) than controls for up to 22 years before diagnosis. The same pattern of increased use was found among CLL patients' children and grandchildren. Our study suggests that CLL diagnosis is preceded by decades of increased susceptibility to infections. The duration of this time window is compatible with causal roles of immune dysfunction and/or certain infections in CLL pathogenesis, possibly mediating the association between constitutional infection susceptibility and CLL risk.

Correction: Epidemiology of bloodstream infections in patients with chronic lymphocytic leukemia: a longitudinal nation-wide cohort study.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.