Brain Abscess Caused by Oral Cavity Bacteria: A Nationwide, Population-based Cohort Study.

BACKGROUND: Oral cavity bacteria are the most frequent etiology of brain abscess. Yet, data on the clinical presentation and outcome are scarce. METHODS: We performed a nationwide, population-based study comprising all adults (aged ≥18 years) with brain abscess due to oral cavity bacteria in Denmark from 2007 through 2020. Prognostic factors for unfavorable outcome (Glasgow outcome scale, 1-4) were examined using modified Poisson regression to compute adjusted relative risks (RRs) with 95% confidence intervals (CIs). RESULTS: Among 287 identified patients, the median age was 58 years (interquartile range, 47-66), and 96 of 287 (33%) were female. Preexisting functional impairment was absent or mild in 253 of 280 (90%), and risk factors for brain abscess included immunocompromise in 95 of 287 (33%), dental infection in 68 of 287 (24%), and ear-nose-throat infection in 33 of 287 (12%). Overall, a neurological deficit was present in 246 of 276 (86%) and in combination with headache and fever in 64 of 287 (22%). Identified microorganisms were primarily the Streptococcus anginosus group, Fusobacterium, Actinomyces, and Aggregatibacter spp., and 117 of 287 (41%) were polymicrobial. Unfavorable outcome occurred in 92 of 246 (37%) at 6 months after discharge and was associated with antibiotics before neurosurgery (RR, 3.28; 95% CI, 1.53-7.04), rupture (RR, 1.89; 95% CI, 1.34-2.65), and immunocompromise (RR, 1.80; 95% CI, 1.29-2.51), but not with specific targeted antibiotic regimens. Identified dental infection was associated with favorable prognosis (RR, 0.58; 95% CI, .36-.93). CONCLUSIONS: Brain abscess due to oral cavity bacteria often occurred in previously healthy individuals without predisposing dental infections. Important risk factors for unfavorable outcome were rupture and immunocompromise. However, outcome was not associated with specific antibiotic regimens supporting carbapenem-sparing strategies.

Risk of tuberculosis after achieving HIV virological suppression on antiretroviral therapy: a Danish nationwide prospective cohort study.

BACKGROUND: In countries with low tuberculosis (TB) burden, the risk of TB in people with HIV (PWH) once HIV virological suppression is achieved is not fully understood. METHODS: In a nationwide cohort, we included all adult PWH from the Danish HIV Cohort initiating antiretroviral therapy (ART) (1995-2017) without prior TB disease. We used Kaplan-Meier estimation and Poisson regression to calculate TB incidence rate (IR) after six months of ART, along with associated risk factors and mortality rates (MR). RESULTS: Among 6,849 PWH initiating ART (median follow-up 7.4 years), 84 developed TB (IR 1.4/1000 person-year [PY]), 54 of them beyond six months of ART initiation, IR 0.97/1000 PY (95%CI:1.17-1.79): 1.95 (95%CI:1.34-2.76) in non-Danish born, 0.36 (95%CI:0.21-0.62) in Danish-born without injection drug use (IDU), and 2.95 (95%CI:1.53-5.66) in Danish-born with IDU. Danish-born with suppressed viremia, and no IDU or known TB exposures had the lowest risk (IR 0.05/1000 PY).In the adjusted analysis, being non-Danish born (aIRR 4.27[95%CI:2.36-7.72]), IDU (aIRR 4.95[95%CI:2.55-9.62]), and previous AIDS-defining events (aIRR 2.05[95%CI:1.06-3.94]) raised TB risk, while suppressed HIV-RNA (aIRR 0.58[95%CI:0.34-0.99]) reduced it. The overall MR for HIV/TB co-infected post- ART was high, at 48.9/1000 PY (95%CI:30.4-78.7). CONCLUSIONS: The TB risk remains elevated in PWH beyond six months of ART initiation, especially among migrants, IDU, those without suppressed HIV-RNA, and individuals exposed to high TB endemic areas or with social risk determinants of health. Conversely, PWH without these risk factors have a TB risk similar to the general population and would not require targeted TB screening strategies.

Update and approach to patients with brain abscess.

PURPOSE OF REVIEW: The epidemiology of brain abscess has changed in recent decades. Moreover, acute and long-term management remains challenging with high risks of mortality and neurological sequelae. This review describes recent advances in epidemiology, diagnosis, and treatment of brain abscess. RECENT FINDINGS: The incidence of brain abscess is increasing, especially among elderly individuals. Important predisposing conditions include dental and ear-nose-throat infections, immuno-compromise, and previous neurosurgery. Molecular-based diagnostics have improved our understanding of the involved microorganisms and oral cavity bacteria including anaerobes are the predominant pathogens. The diagnosis relies upon a combination of magnetic resonance imaging, neurosurgical aspiration or excision, and careful microbiological examinations. Local source control by aspiration or excision of brain abscess combined with long-term antimicrobials are cornerstones of treatment. Long-term management remains important and should address neurological deficits including epilepsy, timely diagnosis and management of comorbidities, and potential affective disorders. SUMMARY: A multidisciplinary approach to acute and long-term management of brain abscess remains crucial and source control of brain abscess by neurosurgery should be pursued whenever possible. Numerous aspects regarding diagnosis and treatment need clarification. Nonetheless, our understanding of this complicated infection is rapidly evolving.

Pulmonary arteriovenous malformations in patients with previous brain abscess: a cross-sectional population-based study.

BACKGROUND AND PURPOSE: Pulmonary arteriovenous malformations (PAVMs) may cause recurrent brain abscess. The primary aim was to determine the prevalence of PAVM amongst survivors of brain abscess. The proportion with cardiac right-to-left shunts was also assessed post hoc. METHODS: This was a cross-sectional population-based study of adult (≥18 years) survivors of cryptogenic bacterial brain abscess in Denmark from 2007 through 2016. Patients were invited for bubble-echocardiography to detect vascular right-to-left shunting and, if abnormal, subsequent computed tomography thorax for diagnosis of PAVM. Data are presented as n/N (%) or median with interquartile range (IQR). RESULTS: Study participation was accepted by 47/157 (30%) eligible patients amongst whom two did not appear for scheduled bubble-echocardiography. The median age of participants was 54 years (IQR 45-62) and 19/57 (33%) were females compared with 59 years (IQR 48-68, p = 0.05) and 41/85 females (48%, p = 0.22) in non-participants. Bubble-echocardiography was suggestive of shunt in 10/45 (22%) participants and PAVM was subsequently confirmed by computed tomography in one patient with grade 1 shunting. The corresponding prevalence of PAVM was 2% (95% confidence interval 0.06-11.8) amongst all examined participants. Another 9/45 (20%) were diagnosed with patent in persistent foramen ovale (n = 8) or atrial septum defect (n = 1), which is comparable with the overall prevalence of 25% amongst adults in the Danish background population. CONCLUSIONS: Undiagnosed PAVM amongst adult survivors of cryptogenic bacterial brain abscess is rare but may be considered in select patients. The prevalence of cardiac right-to-left shunts amongst brain abscess patients corresponds to the prevalence in the general population.

Clinical features and prognostic factors in adults with brain abscess.

Studies on brain abscess are hampered by single-centre design with limited sample size and incomplete follow-up. Thus, robust analyses on clinical prognostic factors remain scarce. This Danish nationwide, population-based cohort study included clinical details of all adults (≥18 years) diagnosed with brain abscess in the Danish National Patient Registry from 2007 through 2014 and the prospective clinical database of the Danish Study Group of Infections of the Brain covering all Danish departments of infectious diseases from 2015 through 2020. All patients were followed for 6 months after discharge. Prognostic factors for mortality at 6 months after discharge were examined by adjusted modified Poisson regression to compute relative risks with 95% confidence intervals (CI). Among 485 identified cases, the median age was 59 years [interquartile range (IQR 48-67)] and 167 (34%) were female. The incidence of brain abscess increased from 0.4 in 2007 to 0.8 per 100 000 adults in 2020. Immuno-compromise was prevalent in 192/485 (40%) and the clinical presentation was predominated by neurological deficits 396/485 (82%), headache 270/411 (66%), and fever 208/382 (54%). The median time from admission until first brain imaging was 4.8 h (IQR 1.4-27). Underlying conditions included dental infections 91/485 (19%) and ear, nose and throat infections 67/485 (14%), and the most frequent pathogens were oral cavity bacteria (59%), Staphylococcus aureus (6%), and Enterobacteriaceae (3%). Neurosurgical interventions comprised aspiration 356/485 (73%) or excision 7/485 (1%) and was preceded by antibiotics in 377/459 (82%). Fatal outcome increased from 29/485 (6%) at discharge to 56/485 (12%) 6 months thereafter. Adjusted relative risks for mortality at 6 months after discharge was 3.48 (95% CI 1.92-6.34) for intraventricular rupture, 2.84 (95% CI 1.45-5.56) for immunocompromise, 2.18 (95% CI 1.21-3.91) for age >65 years, 1.81 (95% CI 1.00-3.28) for abscess diameter >3 cm, and 0.31 (95% CI 0.16-0.61) for oral cavity bacteria as causative pathogen. Sex, neurosurgical treatment, antibiotics before neurosurgery, and corticosteroids were not associated with mortality. This study suggests that prevention of rupture of brain abscess is crucial. Yet, antibiotics may be withheld until neurosurgery, if planned within a reasonable time period (e.g. 24 h), in some clinically stable patients. Adjunctive corticosteroids for symptomatic perifocal brain oedema was not associated with increased mortality.

Risk of Psychiatric Disorders, Use of Psychiatric Hospitals, and Receipt of Psychiatric Medication in Patients With Brain Abscess in Denmark.

BACKGROUND: It is unknown whether patients diagnosed with brain abscess have an increased risk of psychiatric disorders. METHODS: In this nationwide, population-based matched cohort study from Denmark, we compared the incidence of psychiatric disorders, use of psychiatric hospitals, and receipt of psychiatric medications between patients diagnosed with brain abscess and individuals from the general population, matched on date of birth, sex, and residential area. RESULTS: We included 435 patients diagnosed with brain abscess and 3909 individuals in the comparison cohort: 61% were male and median age was 54 years. Patients diagnosed with brain abscess were more likely to suffer from comorbidity. The risk of a hospital diagnosis of psychiatric disorders was increased the first 5 years of observation. In the subpopulation, who had never been in contact with psychiatric hospitals or received psychiatric medication before study inclusion, the risk of developing psychiatric disorders was close to that of the background population, especially when we excluded dementia from this outcome. There was a substantial increase in the receipt of anxiolytics and antidepressants. The difference in the proportion of individuals who received anxiolytics and antidepressants increased from 4% (95% confidence interval [CI], 0%-7%) and 2% (95% CI, -1% to 5%) 2 years before study inclusion to 17% (95% CI, 12%-21%) and 11% (95% CI, 7%-16%) in the year after study inclusion. CONCLUSIONS: Patients with brain abscess without prior psychiatric disorders or receipt of psychiatric medicine are not at increased risk psychiatric disorders diagnosed in psychiatric hospitals, but they have an increased receipt of psychiatric medication.

Experience with sotrovimab treatment of SARS-CoV-2-infected patients in Denmark.

AIMS: To evaluate the experience with use of sotrovimab following severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in high-risk groups. METHODS: In a nationwide, population-based cohort study, we identified all individuals treated with sotrovimab (N = 2933) and stratified them by 4 high-risk groups: (A) malignant haematological disease, (B) solid organ transplantation, (C) anti-CD20 therapy ≤1 year and (D) other risks. Cox regression analysis was used to calculate hazard ratios for hospitalization, death and associated prognostic factors. RESULTS: Of 2933 sotrovimab-treated individuals, 83% belonged to high-risk groups (37.6% haematological malignancy, 27.4% solid organ transplantation and 17.5% treatment with anti-CD20 ≤1 year). Only 17.8% had other risks (11.8% were pregnant, 10.7% primary immunodeficiency, 21.2% other malignancy, 4.3% received anti-CD20 >1 year and 52.0% other/unknown causes). Within 90 days of infusion, 30.2% were hospitalized and 5.3% died. The main prognostic factors were the predefined high-risk groups, mainly malignant haematological disease and age ≥65 years. Number of COVID-19 vaccines (≥3) was associated with a decreased risk of hospitalization. The Delta but not the Omicron BA.2 variant was associated with a higher risk of death compared to the BA.1 variant. CONCLUSION: More than 90% of the patients treated with sotrovimab belonged to the very high-risk groups as described in the Danish guidelines. Sotrovimab-treated individuals remained at a high risk of hospitalization and death which was strongly associated with the underlying immunocompromised state and age. Having received >3 COVID-19 vaccines was association with decreased risk of death and hospitalization.

Dentist's Visits and Risk of Brain Abscess: A Nationwide, Population-Based Case-Control Study.

BACKGROUND: Brain abscesses are frequently caused by oral cavity bacteria, but whether dental status and invasive dental procedures are important risk factors is unknown. METHODS: A nationwide, population-based, case-control study examined the association between dentist's visits and invasive dental procedures and risk of brain abscess caused by oral cavity bacteria from 1989 through 2016. Date of brain abscess diagnosis was considered the index date. Using risk-set sampling, 10 population controls per case were individually matched by age, sex, and residential area. Conditional logistic regression was used to compute odds ratios with 95% confidence intervals (CIs), adjusted for comorbidity. RESULTS: We identified 362 patients with culture-proven brain abscess caused by oral cavity bacteria. The median age was 53 years (interquartile range, 39-65 years) and 220 (61%) were male. Invasive dental procedures within 6 months before the index date was observed in 21 of 362 (6%) patients with brain abscess and 179 of 3257 (5%) population controls (adjusted odds ratio [aOR], 1.07 [95% CI, .67-1.70]). Two hundred thirteen of 362 (59%) patients with brain abscess had visited their dentist within 1 year before the index date compared with 1944 of 3257 (60%) of population controls (aOR, 0.99 [95% CI, .77-1.26]). Using no dentist's visits as reference, we observed aORs of 0.95 (95% CI, .64-1.40) for 1-2 visits within 3 years of the index date and 1.01 (95% CI, .76-1.35) for 3 or more visits. CONCLUSIONS: Recent invasive dental procedures and number of dentist's visits were not associated with culture-verified brain abscess caused by oral cavity bacteria.

Length of stay in Denmark before HIV diagnosis and linkage to care: a population-based study of migrants living with HIV, Denmark, 1995 to 2020.

BackgroundMigrants face an increased risk of HIV infection and late presentation for HIV care.AimTo examine delays in HIV diagnosis, linkage to care (LTC), and risk of late presentation for migrants living with HIV in Denmark.MethodsWe conducted a population-based, nationwide study of adult migrants (n = 2,166) presenting for HIV care between 1 January 1995 and 31 December 2020 in Denmark. Time from immigration to HIV diagnosis and from diagnosis to LTC, and late presentation were assessed, stratified by migrants' geographical regions of origin, using descriptive statistics.ResultsThe demographics of the migrant population changed over time. Overall, migrants diagnosed with HIV after immigration to Denmark resided a median of 3.7 (IQR: 0.8-10.2) years in Denmark before diagnosis. Median time from HIV diagnosis to LTC was 6 (IQR: 0-24) days. Migrants diagnosed with HIV infection before immigration had a median of 38 (IQR: 0-105) days from arrival in Denmark to LTC. The corresponding median times for 2015-20 alone were 4.1 (IQR: 0.9-13.1) years, 0 (IQR: 0-8) days, and 62 (IQR: 25-152) days, respectively. The overall proportion of late presentation among migrants diagnosed with HIV after immigration was 60%, and highest among migrants from sub-Saharan Africa and East and South Asia.ConclusionHIV diagnosis is still substantially delayed in Danish migrants, while LTC is timely. The proportions with late presentation are high. These results call for targeted interventions to reduce the number of migrants with undiagnosed HIV infections and of late presenters.

Venous Thromboembolism and Major Bleeding in Patients With Coronavirus Disease 2019 (COVID-19): A Nationwide, Population-Based Cohort Study.

BACKGROUND: Venous thromboembolism (VTE) is a potentially fatal complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and thromboprophylaxis should be balanced against risk of bleeding. This study examined risks of VTE and major bleeding in hospitalized and community-managed SARS-CoV-2 patients compared with control populations. METHODS: Using nationwide population-based registries, 30-day risks of VTE and major bleeding in SARS-CoV-2 positive patients were compared with those of SARS-CoV-2 test-negative patients and with an external cohort of influenza patients. Medical records of all COVID-19 patients at 6 departments of infectious diseases in Denmark were reviewed in detail. RESULTS: The overall 30-day risk of VTE was 0.4% (40/9460) among SARS-CoV-2 patients (16% hospitalized), 0.3% (649/226 510) among SARS-CoV-2 negative subjects (12% hospitalized), and 1.0% (158/16 281) among influenza patients (59% hospitalized). VTE risks were higher and comparable in hospitalized SARS-CoV-2 positive (1.5%), SARS-CoV-2 negative (1.8%), and influenza patients (1.5%). Diagnosis of major bleeding was registered in 0.5% (47/9460) of all SARS-CoV-2 positive individuals and in 2.3% of those hospitalized. Medical record review of 582 hospitalized SARS-CoV-2 patients observed VTE in 4% (19/450) and major bleeding in 0.4% (2/450) of ward patients, of whom 31% received thromboprophylaxis. Among intensive care patients (100% received thromboprophylaxis), risks were 7% (9/132) for VTE and 11% (15/132) for major bleeding. CONCLUSIONS: Among people with SARS-CoV-2 infection in a population-based setting, VTE risks were low to moderate and were not substantially increased compared with SARS-CoV-2 test-negative and influenza patients. Risk of severe bleeding was low for ward patients, but mirrored VTE risk in the intensive care setting.

Improved Survival Among Hospitalized Patients With Coronavirus Disease 2019 (COVID-19) Treated With Remdesivir and Dexamethasone. A Nationwide Population-Based Cohort Study.

BACKGROUND: There are limited data on outcomes of moderate to severe coronavirus disease 2019 (COVID-19) among patients treated with remdesivir and dexamethasone in a real-world setting. We sought to compare the effectiveness of standard of care (SOC) alone versus SOC plus remdesivir and dexamethasone. METHODS: Two population-based nationwide cohorts of individuals hospitalized with COVID-19 during February through December 2020 were studied. Death within 30 days and need of mechanical ventilation (MV) were compared by inverse probability of treatment weighted (ITPW) logistic regression analysis and shown as odds ratio (OR) with 95% confidence interval (CI). RESULTS: The 30-days mortality rate of 1694 individuals treated with remdesivir and dexamethasone in addition to SOC was 12.6% compared to 19.7% for 1053 individuals receiving SOC alone. This corresponded to a weighted OR of 30-day mortality of 0.47 (95% CI: .38-.57) for patients treated with remdesivir and dexamethasone compared to patients receiving SOC alone. Similarly, progression to MV was reduced (OR 0.36; 95% CI: .29-.46). CONCLUSIONS: Treatment of moderate to severe COVID-19 during June through December that included remdesivir and dexamethasone was associated with reduced 30-day mortality and need of MV compared to treatment in February through May.

Risk of skin cancer in patients with HIV: A Danish nationwide cohort study.

BACKGROUND: The risk of skin cancer in patients with HIV has not been extensively studied. OBJECTIVE: We sought to determine the risk of skin cancer in patients with HIV and compare it with the risk in the background population. METHODS: In a matched, nationwide, population-based cohort study, we compared the risk of skin cancer in 4280 patients with HIV from the Danish HIV cohort study with a background population cohort, according to the level of immunosuppression and route of transmission. Primary outcomes were time to first basal cell carcinoma (BCC), squamous cell carcinoma (SCC), or malignant melanoma. RESULTS: Patients with HIV had an increased risk of BCC and SCC with incident rate ratios of 1.79 (95% confidence interval 1.43-2.22) and 5.40 (95% confidence interval 3.07-9.52), respectively, compared with the background population. We observed no increased risk of malignant melanoma. Low nadir CD4 cell count was associated with an increased risk of SCC. The increased risk of BCC among patients with HIV was restricted to men who had sex with men. LIMITATIONS: This study was observational and included a small number of patients with melanoma. CONCLUSION: Patients with HIV have an increased risk of BCC and SCC. Low nadir, but not current, CD4 cell count as a marker of immunosuppression was associated with an increased risk of SCC.

Fracture risk in hepatitis C virus infected persons: results from the DANVIR cohort study.

BACKGROUND & AIMS: The association between Hepatitis C virus (HCV)-infection and fracture risk is not well characterized. We compared fracture risk between HCV-seropositive (HCV-exposed) patients and the general population and between patients with cleared and chronic HCV-infection. METHODS: Outcome measures were time to first fracture at any site, time to first low-energy and first non-low-energy (other) fracture in 12,013 HCV-exposed patients from the DANVIR cohort compared with a general population control cohort (n=60,065) matched by sex and age. Within DANVIR, 4500 patients with chronic HCV-infection and 2656 patients with cleared HCV-infection were studied. RESULTS: Compared with population controls, HCV-exposed patients had increased overall risk of fracture [adjusted incidence rate ratio (aIRR) 2.15, 95% Confidence Interval (CI) 2.03-2.28], increased risk of low-energy fracture (aIRR 2.13, 95% CI: 1.93-2.35) and of other fracture (aIRR 2.18, 95% CI: 2.02-2.34). Compared with cleared HCV-infection, chronic HCV-infection was not associated with increased risk of fracture at any site (aIRR 1.08, 95% CI: 0.97-1.20), or other fracture (aIRR 1.04, 95% CI: 0.91-1.19). The aIRR for low-energy fracture was 1.20 (95% CI: 0.99-1.44). CONCLUSIONS: HCV-exposed patients had increased risk of all fracture types. In contrast, overall risk of fracture did not differ between patients with chronic vs. cleared HCV-infection, although chronic HCV-infection might be associated with a small excess risk of low-energy fractures. Our study suggests that fracture risk in HCV-infected patients is multi-factorial and mainly determined by lifestyle-related factors associated with HCV-exposure.

Repeated doxycycline treatment among patients with neuroborreliosis: a nationwide, population-based, registry-based, matched cohort study.

OBJECTIVES: To investigate receipt of antibiotics among patients with neuroborreliosis after initial antibiotic treatment, likely attributable to posttreatment symptoms. METHODS: We performed a nationwide, matched, population-based cohort study in Denmark (2009-2021). We included all Danish patients with neuroborreliosis, i.e. a positive Borrelia burgdorferi intrathecal antibody index test and a cerebrospinal fluid leukocyte count ≥10 × 106/l, and initially treated with doxycycline. To form a comparison cohort, we randomly extracted individuals from the general population matched 1:10 to patients with neuroborreliosis on date of birth and sex. The main outcome was receipt of doxycycline, and the secondary outcome was receipt of phenoxymethylpenicillin. We calculated short-term (<1 year) and long-term (≥1 year) hazard ratios (HR) with 95% confidence intervals (95%CI). RESULTS: We included 463 patients with neuroborreliosis and 2,315 comparison cohort members. Compared with the comparison cohort members, patients with neuroborreliosis initially treated with doxycycline had increased receipt of additional doxycycline within 1 year (HR: 38.6, 95%CI: 17.5-85.0) and ≥1 years (HR: 3.5, 95%CI: 1.9-6.3). Compared with comparison cohort members, patients with neuroborreliosis had no increased receipt of phenoxymethylpenicillin (<1 year HR 1.0, 95%CI: 0.7-1.3; ≥1 years HR 1.2, 95%CI: 0.9-1.5). CONCLUSIONS: After initial antibiotic treatment, patients with neuroborreliosis have increased receipt of doxycycline particularly within one year after initial antibiotic therapy but also subsequently. The lack of increased receipt of phenoxymethylpenicillin suggests that the receipt of doxycycline was not merely due to differences in healthcare-seeking behaviour, increased risk of early Lyme borreliosis due to exposure, or differences in antibacterial usage in general.

Survival among people with HIV and their families in Denmark 1995-2021: a nationwide population-based cohort study.

Background: Survival among people with HIV (PWH) has vastly improved globally over the last few decades but remains lower than among the general population. We aimed to estimate time trends of survival among PWH and their families from 1995 to 2021. Methods: We conducted a registry-based, nationwide, population-based, matched cohort study. We included all Danish-born PWH from 1995 to 2021 who had been on antiretroviral therapy for 90 days, did not report intravenous drug use, and were not co-infected with hepatitis C (n = 4168). We matched population controls from the general population 10:1 to PWH by date of birth and sex (n = 41,680). For family cohorts, we identified siblings, mothers, and fathers of PWH and population controls. From Kaplan-Meier tables with age as time scale, we estimated survival from age 25. We compared PWH with population controls and families of PWH with families of population controls to calculate mortality rate ratios adjusted for sex, age, comorbidities, and education (aMRR). Findings: The median age of death among PWH increased from 27.5 years in 1995-1997 to 73.9 years (2010-2014), but thereafter survival increased only marginally. From 2015 to 2021, mortality was increased among PWH (aMRR 1.87 (95% CI: 1.65-2.11)) and siblings (aMRR: 1.25 (95% CI: 1.07-1.47)), mothers (aMRR: 1.30 (95% CI: 1.17-1.43)), and fathers (aMRR: 1.15 (95% CI: 1.03-1.29)) of PWH compared to their respective control cohorts. Mortality among siblings of PWH who reported heterosexual route of HIV transmission (aMRR: 1.51 (95% CI: 1.16-1.96)) was higher than for siblings of PWH who reported men who have sex with men as route of HIV transmission (aMRR 1.19 (95% CI: 0.98-1.46)). Interpretation: Survival among PWH improved substantially until 2010, after which it increased only marginally. This may partly be due to social and behavioural factors as PWH families also had higher mortality. Funding: Preben and Anna Simonsen's Foundation and Independent Research Fund Denmark.

Obtainment of prescribed analgesics among patients with Lyme neuroborreliosis; a nationwide, population-based matched cohort study.

BACKGROUND: Radicular pain is the most predominant symptom among adults with Lyme neuroborreliosis (LNB) but the duration preceding and following diagnosis remains unknown. We aimed to investigate whether patients with LNB have increased obtainment of analgesics before and after diagnosis and for how long. METHODS: We performed a nationwide, population-based, matched cohort study (2009-2021). all Danish residents with LNB (positive Borrelia burgdorferi intrathecal antibody index test and cerebrospinal fluid pleocytosis) were included. To form a comparison cohort, individuals from the general population were randomly extracted and matched 10:1 to patients with LNB on age and sex. Outcomes were obtainment of simple analgesics, antiepileptics, tricyclic antidepressants, serotonin and noradrenaline reuptake inhibitors, tramadol, and other opioids. We calculated monthly and six-monthly proportions of individuals with obtainment of analgesics and absolute risk differences. RESULTS: 1,056 patients with LNB and 10,560 comparison cohort members were included. An increased proportion of patients with LNB obtained analgesics from 3 months before study inclusion, especially simple analgesics, tramadol, and other opioids. Within the 0-1-month period after study inclusion, patients with LNB most frequently obtained simple analgesics (15 %), antiepileptics (11 %), and tramadol (10 %). Thereafter, obtainment of analgesics declined within a few months. A slightly larger proportion of patients with LNB obtained antiepileptics up to 2.5 years after diagnosis. CONCLUSIONS: Up to 3 months preceding diagnosis, LNB was preceded by increased obtainment of analgesics, which suggests diagnostic delay. Importantly, most patients with LNB did not obtain analgesics after the immediate disease course, although obtainment remained more frequent up to 2.5 years after.

Healthcare-seeking behaviour preceding diagnosis of Lyme neuroborreliosis: population-based nationwide matched nested case-control study.

OBJECTIVES: To identify diagnostic opportunities, we investigated healthcare-seeking behaviour among patients with Lyme neuroborreliosis (LNB) within 28 weeks before diagnosis. METHODS: We conducted a population-based, nationwide matched nested case-control study (Denmark, 2009-2021). As cases, we included all Danish residents with LNB (positive Borrelia burgdorferi intrathecal antibody index test and cerebrospinal fluid pleocytosis). We randomly selected controls from the general population and matched 10:1 on date of birth and sex. Exposures were assignment of diagnostic codes for symptoms, contact to medical specialties, medical wandering, and undergoing diagnostic procedures. We calculated the weekly and 3-month proportions of individuals with exposures and calculated absolute risk differences with corresponding 95% CI. RESULTS: We included 1056 cases with LNB and 10 560 controls. Within 3 months before diagnosis, the most frequent assigned symptoms were pain (difference: 13.0%, 95% CI: 10.9-15.1). Cases with LNB exhibited increased contact with most specialties, particularly general practitioners (difference: 48.7%, 95% CI: 46.0-51.4), neurology (difference: 14.3%, 95% CI: 11.7-16.8), and internal medicine (difference: 11.1%, 95% CI: 8.7-13.5), and medical wandering (difference: 17.1%, 95% CI: 14.3-20.0). Common diagnostic procedures included imaging of the brain (difference: 10.2, 95% CI: 8.3-12.1), the spine (difference: 8.8%, 85% CI: 7.0-10.6), and the abdomen (difference: 7.2%, 95% CI: 5.4-9.1). The increase in healthcare-seeking behaviour was observed ≤12 weeks preceding diagnosis. DISCUSSION: Pain appears to be an ambiguous symptom of LNB, potentially contributing to delays in establishing the correct diagnosis. It would be difficult to identify patients with LNB more effectively as the increased healthcare-seeking behaviour preceding diagnosis is distributed across many medical specialties.

Risk of haematologic cancers among individuals tested for Borrelia burgdorferi antibodies, and Borrelia burgdorferi seropositive individuals: a nationwide population-based matched cohort study.

OBJECTIVES: In a nationwide, matched cohort study, we aimed to investigate risks of haematologic cancers among individuals tested for Borrelia burgdorferi (Bb) antibodies, and among serum Bb seropositive individuals. METHODS: We identified all Bb seropositive individuals in Denmark (1993-2020) (n = 52 200) and constructed two age- and sex-matched comparison cohorts: (a) Bb seronegative controls (n = 104 400) and (b) background population controls (n = 261 000). We calculated short-term OR (aOR) (<1 month of study inclusion), and long-term hazard ratios (aHR) (>1 month after study inclusion) adjusted for age and sex. We stratified seropositive individuals on only Bb-IgM seropositive (n = 26 103), only Bb-IgG seropositive (n = 18 698), and Bb-IgM-and-IgG seropositive (n = 7399). RESULTS: Compared with the background population, individuals tested for Bb antibodies had increased short-term (aOR: 12.6, 95% CI: 10.1-15.6) and long-term (aHR: 1.3, 95% CI: 1.2-1.4) risk of haematologic cancers. The Bb seropositive individuals had no increased risk of haematologic cancers compared with those who tested negative for Bb, except that Bb-IgM-and-IgG seropositive individuals had increased long-term risk of chronic lymphatic leukaemia (aHR: 2.0, 95% CI: 1.2-3.4). DISCUSSION: Our results suggest that Bb antibody testing is included in the work-up of unspecific symptoms preceding diagnosis of haematologic cancers. Bb-IgM-and-IgG seropositivity was associated with a two-fold increased long-term risk of chronic lymphatic leukaemia, which warrants further investigation.