Statistical normalization techniques for magnetic resonance imaging

While computed tomography and other imaging techniques are measured in absolute units with physical meaning, magnetic resonance images are expressed in arbitrary units that are difficult to interpret and differ between study visits and subjects. Much work in the image processing literature on intensity normalization has focused on histogram matching and other histogram mapping techniques, with little emphasis on normalizing images to have biologically interpretable units. Furthermore, there are no formalized principles or goals for the crucial comparability of image intensities within and across subjects. To address this, we propose a set of criteria necessary for the normalization of images. We further propose simple and robust biologically motivated normalization techniques for multisequence brain imaging that have the same interpretation across acquisitions and satisfy the proposed criteria. We compare the performance of different normalization methods in thousands of images of patients with Alzheimer's disease, hundreds of patients with multiple sclerosis, and hundreds of healthy subjects obtained in several different studies at dozens of imaging centers.

Neurological injury in adults treated with extracorporeal membrane oxygenation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) may be urgently used as a last resort form of life support when all other treatment options for potentially reversible cardiopulmonary injury have failed.

OBJECTIVE

To examine the range and frequency of neurological injury in ECMO-treated adults.

DESIGN

Retrospective clinicopathological cohort study.

SETTING

Mayo Clinic, Rochester, Minnesota.

PATIENTS

A prospectively collected registry of all patients 15 years or older treated with ECMO for 12 or more hours from January 2002 to April 2010.

INTERVENTION

Patients were analyzed for potential risk factors for neurological events and death using logistic regression and Cox proportional hazards models.

MAIN OUTCOME MEASURES

Neurological diagnosis and/or death.

RESULTS

A total of 87 adults were treated (35 female [40%]; median age, 54 years [interquartile range, 31]; mean duration of ECMO, 91 hours [interquartile range, 100]; overall survival >7 days after ECMO, 52%). Neurological events occurred in 42 patients who received ECMO (50%; 95% confidence interval [CI], 39%-61%). Diagnoses included subarachnoid hemorrhage, ischemic watershed infarctions, hypoxic-ischemic encephalopathy, unexplained coma, and brain death. Death in patients who received ECMO who did not require antecedent cardiopulmonary resuscitation was associated with increased age (odds ratio, 1.24 per decade; 95% CI, 1.03-1.50; P = .02) and lower minimum arterial oxygen pressure (odds ratio, 0.79; 95% CI, 0.68-0.92; P = .03). Although stroke was rarely diagnosed clinically, 9 of 10 brains studied at autopsy demonstrated hypoxic-ischemic and hemorrhagic lesions of vascular origin.

CONCLUSION

Severe neurological sequelae occur frequently in adult ECMO-treated patients with otherwise reversible cardiopulmonary injury (conservative estimate, 50%) and include a range of potentially fatal neurological diagnoses that may be due to the precipitating event and/or ECMO treatment.

Night-shift work and risk of breast cancer: a systematic review and meta-analysis

A 2007 report by the International Agency for Research on Cancer classified night-shift work as possibly carcinogenic to humans, emphasizing, in particular, its association with breast cancer. Since this report and the publication of the last systematic review on this topic, several new studies have examined this association. Hence, to provide a comprehensive update on this topic, we performed a systematic review and meta-analysis. We searched Medline, Embase, CINAHL, Web of Science (Conference Proceedings), and ProQuest dissertations for studies published before March 1, 2012, along with a manual search of articles that cited or referenced the included studies. Included were observational case-control or cohort studies examining the association between night-shift work and breast carcinogenesis in women, which all ascertained and quantified night-shift work exposure. The search yielded 15 eligible studies for inclusion in the systematic review and meta-analysis. Using random-effects models, the pooled relative risk (RR) and 95 % confidence intervals (CIs) of breast cancer for individuals with ever night-shift work exposure was 1.21 (95 % CI, 1.00-1.47, p = 0.056, I (2) = 76 %), for short-term night-shift workers (<8 years) was 1.13 (95 % CI, 0.97-1.32, p = 0.11, I (2) = 79 %), and for long-term night-shift workers (≥8 years) was 1.04 (95 % CI, 0.92-1.18, p = 0.51, I (2) = 55 %), with substantial between-study heterogeneity observed in all analyses. Subgroup analyses suggested that flight attendants with international or overnight work exposure and nurses working night-shifts long-term were at increased risk of breast cancer, however, these findings were limited by unmeasured confounding. Overall, given substantial heterogeneity observed between studies in this meta-analysis, we conclude there is weak evidence to support previous reports that night-shift work is associated with increased breast cancer risk.

Progressive multifocal leukoencephalopathy in transplant recipients

OBJECTIVE

Transplant recipients are at risk of developing progressive multifocal leukoencephalopathy (PML), a rare demyelinating disorder caused by oligodendrocyte destruction by JC virus.

METHODS

Reports of PML following transplantation were found using PubMed Entrez (1958-July 2010). A multicenter, retrospective cohort study also identified all cases of PML among transplant recipients diagnosed at Mayo Clinic, Johns Hopkins University, Washington University, and Amsterdam Academic Medical Center. At 1 institution, the incidence of posttransplantation PML was calculated.

RESULTS

A total of 69 cases (44 solid organ, 25 bone marrow) of posttransplantation PML were found including 15 from the 4 medical centers and another 54 from the literature. The median time to development of first symptoms of PML following transplantation was longer in solid organ vs bone marrow recipients (27 vs 11 months, p = 0.0005, range of <1 to >240). Median survival following symptom onset was 6.4 months in solid organ vs 19.5 months in bone marrow recipients (p = 0.068). Case fatality was 84% (95% confidence interval [CI], 70.3-92.4%) and survival beyond 1 year was 55.7% (95% CI, 41.2-67.2%). The incidence of PML among heart and/or lung transplant recipients at 1 institution was 1.24 per 1,000 posttransplantation person-years (95% CI, 0.25-3.61). No clear association was found with any 1 immunosuppressant agent. No treatment provided demonstrable therapeutic benefit.

INTERPRETATION

The risk of PML exists throughout the posttransplantation period. Bone marrow recipients survive longer than solid organ recipients but may have a lower median time to first symptoms of PML. Posttransplantation PML has a higher case fatality and may have a higher incidence than reported in human immunodeficiency virus (HIV) patients on highly-active antiretroviral therapy (HAART) or multiple sclerosis patients treated with natalizumab.

Brain death declaration: Practices and perceptions worldwide

OBJECTIVE

To assess the practices and perceptions of brain death determination worldwide and analyze the extent and nature of variations among countries.

METHODS

An electronic survey was distributed globally to physicians with expertise in neurocritical care, neurology, or related disciplines who would encounter patients at risk of brain death.

RESULTS

Most countries (n = 91, response rate 76%) reported a legal provision (n = 63, 70%) and an institutional protocol (n = 70, 77%) for brain death. Institutional protocols were less common in lower-income countries (2/9 of low [22%], 9/18 lower-middle [50%], 22/26 upper-middle [85%], and 37/38 high-income countries [97%], p < 0.001). Countries with an organized transplant network were more likely to have a brain death provision compared with countries without one (53/64 [83%] vs 6/25 [24%], p < 0.001). Among institutions with a formalized brain death protocol, marked variability occurred in requisite examination findings (n = 37, 53% of respondents deviated from the American Academy of Neurology criteria), apnea testing, necessity and type of ancillary testing (most commonly required test: EEG [n = 37, 53%]), time to declaration, number and qualifications of physicians present, and criteria in children (distinct pediatric criteria: n = 38, 56%).

CONCLUSIONS

Substantial differences in perceptions and practices of brain death exist worldwide. The identification of discrepancies, improvement of gaps in medical education, and formalization of protocols in lower-income countries provide first pragmatic steps to reconciling these variations. Whether a harmonized, uniform standard for brain death worldwide can be achieved remains questionable.

Titles versus titles and abstracts for initial screening of articles for systematic reviews

Background

There is no consensus on whether screening titles alone or titles and abstracts together is the preferable strategy for inclusion of articles in a systematic review.

Methods

Two methods of screening articles for inclusion in a systematic review were compared: titles first versus titles and abstracts simultaneously. Each citation found in MEDLINE or Embase was reviewed by two physician reviewers for prespecified criteria: the citation included (1) primary data; (2) the exposure of interest; and (3) the outcome of interest.

Results

There were 2965 unique citations. The titles first strategy resulted in an immediate rejection of 2558 (86%) of the records after reading the title alone, requiring review of 239 titles and abstracts, and subsequently 176 full text articles. The simultaneous titles and abstracts review led to rejection of 2782 citations (94%) and review of 183 full text articles. Interreviewer agreement to include an article for full text review using the titles-first screening strategy was 89%–94% (kappa = 0.54) and 96%–97% (kappa = 0.56) for titles and abstracts combined. The final systematic review included 13 articles, all of which were identified by both screening strategies (yield 100%, burden 114%). Precision was higher in the titles and abstracts method (7.1% versus 3.2%) but recall was the same (100% versus 100%), leading to a higher F-measure for the titles and abstracts approach (0.1327 versus 0.0619).

Conclusion

Screening via a titles-first approach may be more efficient than screening titles and abstracts together.

Availability, accessibility, and affordability of neurodiagnostic tests in 37 countries

OBJECTIVE

To determine the availability, accessibility, and affordability of EEG, EMG, CSF analysis, head CT, and brain MRI for neurologic disorders across countries.

METHODS

An online, 60-question survey was distributed to neurology practitioners in 2014 to assess the presence, wait time, and cost of each test in private and public health sectors. Data were stratified by World Bank country income group. Affordability was calculated with reference to the World Health Organization's definition of catastrophic health expenditure as health-related out-of-pocket expenditure of >40% of disposable household income, and assessment of providers' perceptions of affordability to the patient.

RESULTS

Availability of EEG and EMG is correlated with higher World Bank income group (correlation coefficient 0.38, test for trend p = 0.046; 0.376, p = 0.043); CSF, CT, and MRI did not show statistically significant associations with income groups. Patients in public systems wait longer for neurodiagnostic tests, especially MRI, EEG, and urgent CT (p < 0.0001). The mean cost per test, across all tests, was lower in the public vs private sector (US $55.25 vs $214.62, p < 0.001). Each drop in World Bank income group is associated with a 29% decrease in the estimated share of the population who can afford a given test (95% confidence interval -33.4, 25.2; p < 0.001). In most low-income countries surveyed, only the top 10% or 20% of the population was able to afford tests below catastrophic levels. In surveyed lower-middle-income countries, >40% of the population, on average, could not afford neurodiagnostic tests.

CONCLUSIONS

Neurodiagnostic tests are least affordable in the lowest income settings. Closing this "diagnostic gap" for countries with the lowest incomes is essential.

Acute Disseminated Encephalomyelitis and Acute Hemorrhagic Leukoencephalitis Following COVID-19: Systematic Review and Meta-synthesis

BACKGROUND AND OBJECTIVES

Since the onset of the COVID-19 pandemic, a growing number of reports have described cases of acute disseminated encephalomyelitis (ADEM) and acute hemorrhagic leukoencephalitis (AHLE) following infection with COVID-19. Given their relatively rare occurrence, the primary objective of this systematic review was to synthesize their clinical features, response to treatments, and clinical outcomes to better understand the nature of this neurologic consequence of COVID-19 infection.

METHODS

Patients with a history of COVID-19 infection were included if their reports provided adequate detail to confirm a diagnosis of ADEM or AHLE by virtue of clinical features, radiographic abnormalities, and histopathologic findings. Cases purported to be secondary to vaccination against COVID-19 or occurring in the context of a preexisting relapsing CNS demyelinating disease were excluded. Case reports and series were identified via PubMed on May 17, 2021, and 4 additional cases from the authors' hospital files supplemented the systematic review of the literature. Summary statistics were used to describe variables using a complete case analysis approach.

RESULTS

Forty-six patients (28 men, median age 49.5 years, 1/3 >50 years old) were analyzed, derived from 26 case reports or series originating from 8 countries alongside 4 patient cases from the authors' hospital files. COVID-19 infection was laboratory confirmed in 91% of cases, and infection severity necessitated intensive care in 67%. ADEM occurred in 31 cases, whereas AHLE occurred in 15, with a median presenting nadir modified Rankin Scale score of 5 (bedridden). Anti-MOG seropositivity was rare (1/15 patients tested). Noninflammatory CSF was present in 30%. Hemorrhage on brain MRI was identified in 42%. Seventy percent received immunomodulatory treatments, most commonly steroids, IV immunoglobulins, or plasmapheresis. The final mRS score was ≥4 in 64% of patients with adequate follow-up information, including 32% who died.

DISCUSSION

In contrast to ADEM cases from the prepandemic era, reported post-COVID-19 ADEM and AHLE cases were often advanced in age at onset, experienced severe antecedent infection, displayed an unusually high rate of hemorrhage on neuroimaging, and routinely had poor neurologic outcomes, including a high mortality rate. Findings are limited by nonstandardized reporting of cases, truncated follow-up information, and presumed publication bias.

Cancer in refugees in Jordan and Syria between 2009 and 2012: challenges and the way forward in humanitarian emergencies

Treatment of non-communicable diseases such as cancer in refugees is neglected in low-income and middle-income countries, but is of increasing importance because the number of refugees is growing. The UNHCR, through exceptional care committees (ECCs), has developed standard operating procedures to address expensive medical treatment for refugees in host countries, to decide on eligibility and amount of payment. We present data from funding applications for cancer treatments for refugees in Jordan between 2010 and 2012, and in Syria between 2009 and 2011. Cancer in refugees causes a substantial burden on the health systems of the host countries. Recommendations to improve prevention and treatment include improvement of health systems through standard operating procedures and innovative financing schemes, balance of primary and emergency care with expensive referral care, development of electronic cancer registries, and securement of sustainable funding sources. Analysis of cancer care in low-income refugee settings, particularly in sub-Saharan Africa, is needed to inform future responses.

Tumor-Educated Platelet RNA for the Detection and (Pseudo)progression Monitoring of Glioblastoma

Tumor-educated platelets (TEPs) are potential biomarkers for cancer diagnostics. We employ TEP-derived RNA panels, determined by swarm intelligence, to detect and monitor glioblastoma. We assessed specificity by comparing the spliced RNA profile of TEPs from glioblastoma patients with multiple sclerosis and brain metastasis patients (validation series, n = 157; accuracy, 80%; AUC, 0.81 [95% CI, 0.74–0.89; p < 0.001]). Second, analysis of patients with glioblastoma versus asymptomatic healthy controls in an independent validation series (n = 347) provided a detection accuracy of 95% and AUC of 0.97 (95% CI, 0.95–0.99; p < 0.001). Finally, we developed the digitalSWARM algorithm to improve monitoring of glioblastoma progression and demonstrate that the TEP tumor scores of individual glioblastoma patients represent tumor behavior and could be used to distinguish false positive progression from true progression (validation series, n = 20; accuracy, 85%; AUC, 0.86 [95% CI, 0.70–1.00; p < 0.012]). In conclusion, TEPs have potential as a minimally invasive biosource for blood-based diagnostics and monitoring of glioblastoma patients.

TEP RNA enables blood-based brain tumor diagnostics

TEP RNA is dynamic throughout anti-tumor treatment

TEP RNA may be employed for therapy monitoring

Clinically suspected fibrocartilaginous embolism: clinical characteristics, treatments, and outcomes

OBJECTIVE

To study the frequency, demographics, clinical characteristics, and outcomes of patients with an antemortem diagnosis of fibrocartilaginous embolism (FCE), a rare cause of spinal cord and cerebral infarction because of the presumed embolization of nucleus pulposus material into the vascular circulation.

METHODS

We retrospectively reviewed the institutional experience of patients who received an antemortem diagnosis of FCE by their treating physician at the Mayo Clinic (Rochester, MN, USA) from 1997 to 2009. All patients underwent laboratory, radiological, and clinical exclusion of other possible and related diagnoses.

RESULTS

Of 164 patients with acute spinal cord infarction seen during the study timeframe, 9 (5.5%; 95% CI 2.5, 10.2%) met inclusion criteria for high likelihood of FCE (6 men, 3 women; median age 46 years old, range 21-64). All patients were severely affected (median modified Rankin Scale 4, median Barthel index 45; mean time to evaluation 57 days). One patient (1/9) experienced concomitant cerebral infarction. No patients had noticeable improvement from steroid treatment.

CONCLUSION

The diagnosis of FCE in life is common at this referral center, accounting for 5.5% of all cases of acute spinal cord infarction seen. Although FCE is a postmortem diagnosis, we propose clinical criteria for FCE in life to better characterize the relatively high number of patients with unexplained ischaemic myelopathy.

High risk of postpartum relapses in neuromyelitis optica spectrum disorder

OBJECTIVE

To study the effect of pregnancy on the frequency of neuromyelitis optica spectrum disorder (NMOSD) relapse and evaluate rates of pregnancy-related complications in an international multicenter setting.

METHODS

We administered a standardized survey to 217 women with NMOSD from 7 medical centers and reviewed their medical records. We compared the annualized relapse rate (ARR) during a baseline period 2 years prior to a participant's first pregnancy to that during pregnancy and to the 9 months postpartum. We also assessed pregnancy-related complications.

RESULTS

There were 46 informative pregnancies following symptom onset in 31 women with NMOSD. Compared to baseline (0.17), ARR was increased both during pregnancy (0.44; p = 0.035) and during the postpartum period (0.69; p = 0.009). The highest ARR occurred during the first 3 months postpartum (ARR 1.33). A total of 8 of 76 (10.5%) with onset of NMOSD prior to age 40 experienced their initial symptom during the 3 months postpartum, 2.9 times higher than expected.

CONCLUSIONS

The postpartum period is a particularly high-risk time for initial presentation of NMOSD. In contrast to published observations in multiple sclerosis, in neuromyelitis optica, relapse rate during pregnancy was also increased, although to a lesser extent than after delivery.

Susac syndrome: clinical characteristics and treatment in 29 new cases

BACKGROUND AND PURPOSE

  There are few clinical studies on the attempted treatments and outcomes in patients with Susac syndrome (SS) (retinocochleocerebral vasculopathy).

METHODS

  A retrospective review was performed of all patients presenting with SS at the Mayo Clinic in Rochester, Minnesota, USA (1 January 1998-1 October 2011).

RESULTS

  There were 29 cases of SS (24 women, mean age at presentation, 35 years; range, 19-65; full triad of brain, eye, and ear involvement, n = 16; mean follow-up time, 29 months). Thirty CSF analyses were performed in 27 cases (mean protein 130 mg/dl, range 35-268; mean cell count 14, range 1-86). MRI of the brain showed corpus callosal involvement (79%), T2-weighted hyperintensities (93%), and gadolinium enhancement (50%). Average lowest modified Rankin Scale score was 2.5 (median 2, range 0-5). Most patients (93%) received immunosuppressive treatment, with a mean time to treatment of 2 months following symptomatic onset. Treatments included intravenous methylprednisolone or dexamethasone (n = 23), oral corticosteroids (n = 24), plasma exchange (PLEX) (n = 9), intravenous immunoglobulin (IVIg) (n = 15), cyclophosphamide (n = 6), mycophenolate mofetil (n = 5), azathioprine (n = 2), and rituximab (n = 1). Most patients also received an antiplatelet agent (n = 21). Improvement or stabilization was noted in eight of 11 cases treated with IVIg in the acute period (three experienced at least partial deterioration) and eight of nine cases of PLEX treatment (one lost to follow up).

CONCLUSIONS

  Susac syndrome may be severe, disabling, and protracted in some patients. PLEX may be an adjunct or alternative therapy for patients who do not experience symptomatic improvement following steroid treatment.

Neurologic disorders incidence in HIV+ vs HIV- men: Multicenter AIDS Cohort Study, 1996-2011

OBJECTIVE

To study the incidence and pattern of neurologic disorders in a large cohort of HIV-positive men, compared with HIV-negative men, in the era of highly active antiretroviral therapy (HAART).

METHODS

The Multicenter AIDS Cohort Study is a prospective study of men who have sex with men enrolled in 4 cities in the United States. We compared HIV-positive vs HIV-negative men for incidence and category of neurologic diagnoses in the HAART era (July 1, 1996, to last known follow-up or death, on or before July 1, 2011).

RESULTS

There were 3,945 participants alive during the HAART era (2,083 HIV negative, 1,776 HIV positive, and 86 who became infected with HIV during the study period) including 3,427 who were older than 40 years of age. Median age at first neurologic diagnosis among all participants alive in the HAART era was lower in HAART-treated HIV-positive vs HIV-negative men (48 vs 57 years of age, p < 0.001). Incidence of neurologic diagnoses was higher in HAART-treated HIV-positive vs HIV-negative men (younger than 40 years: 11.4 vs 0 diagnoses per 1,000 person-years [p < 0.001]; 40-49 years: 11.6 vs 2.0 [p < 0.001]; 50-60 years: 15.1 vs 3.0 [p < 0.001]; older than 60 years: 17.0 vs 5.7 [p < 0.01]). Excess neurologic disease was found in the categories of nervous system infections (p < 0.001), dementia (p < 0.001), seizures/epilepsy (p < 0.01), and peripheral nervous system disorders (p < 0.001), but not stroke (p = 0.60).

CONCLUSIONS

HIV-positive men receiving HAART have a higher burden of neurologic disease than HIV-negative men and develop neurologic disease at younger ages.

Childhood deprivation and later-life cognitive function in a population-based study of older rural South Africans

RATIONALE

Little research has evaluated the life course drivers of cognitive aging in South Africa.

OBJECTIVES

We investigated the relationships of self-rated childhood health and father's occupation during childhood with later-life cognitive function score and whether educational attainment mediated these relationships among older South Africans living in a former region of Apartheid-era racial segregation.

METHODS

Data were from baseline assessments of "Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community" (HAALSI), a population-based study of 5059 men and women aged ≥40 years in 2015 in rural Agincourt sub-district, South Africa. Childhood health, father's occupation during childhood, and years of education were self-reported in study interviews. Cognitive measures assessed time orientation, numeracy, and word recall, which were included in a z-standardized latent cognitive function score variable. Linear regression models adjusted for age, sex, and country of birth were used to estimate the total and direct effects of each childhood risk factor, and the indirect effects mediated by years of education.

RESULTS

Poor childhood health predicted lower cognitive scores (total effect = -0.28; 95% CI = -0.35, -0.21, versus good); this effect was not mediated by educational attainment. Having a father in a professional job during childhood, while rare (3% of sample), predicted better cognitive scores (total effect = 0.25; 95% CI = 0.10, 0.40, versus unskilled manual labor, 29% of sample). Half of this effect was mediated by educational attainment. Education was linearly associated with later-life cognitive function score (0.09; 95% CI = 0.09, 0.10 per year achieved).

CONCLUSION

In this post-Apartheid, rural South African context, older adults with poor self-reported childhood health or whose father worked in unskilled manual labor had relatively poor cognitive outcomes. Educational attainment strongly predicted cognitive outcomes, and appeared to be, in part, a mechanism of social stratification in later-life cognitive health in this context.

Outcomes of Thrombolysis for Acute Ischemic Stroke in Octogenarians Versus Nonagenarians

Background and Purpose— Little is reported on the outcomes of nonagenarians who are treated with intravenous tissue plasminogen activator for acute ischemic stroke. It is uncertain whether nonagenarians have higher mortality and worse functional outcomes than octogenarians.

Methods— All patients who were ≥80 years of age were extracted from the Canadian Activase for Stroke Effectiveness Study national registry, a 60-center Canadian acute ischemic stroke treatment network. Patients were divided into 2 groups: those who were 80 to 89 years of age (octogenarians) and those who were 90 to 99 years of age (nonagenarians), and compared by baseline clinical, demographic, treatment, and outcome-related measures.

Results— Twenty-eight nonagenarians and 242 octogenarians were treated with intravenous tissue plasminogen activator for acute ischemic stroke over the 2.5-year observation period. Nonagenarians and octogenarians did not differ on any of the baseline clinical or demographic variables. Both groups were predominantly female (77% nonagenarians and 61% octogenarians), hypertensive (54% and 60%), and predominantly had severe strokes (National Institutes of Health Stroke Scale score >15; 58% and 52%). The rate of symptomatic intracerebral hemorrhage (7% nonagenarians versus 4% octogenarians; P =0.359), 90-day mortality (52% versus 33%; P =0.087), and 30-day favorable functional outcomes ([modified Rankin score ≤1] 30% versus 26%; P =0.647) showed no statistically significant difference when comparing the 2 age groups.

Conclusions— There is no significant difference in 90-day mortality, 30-day functional outcome, or rate of symptomatic intracerebral hemorrhage between nonagenarians and octogenarians treated with intravenous tissue plasminogen activator when comparing populations of similar baseline risk.

Progressive multifocal leukoencephalopathy: A 25-year retrospective cohort study

OBJECTIVE

To characterize the risk factors, clinical course, and treatment of patients with progressive multifocal leukoencephalopathy (PML) diagnosed and followed over a 25-year epoch at 2 academic hospitals.

METHODS

Patients with a definite diagnosis of PML were identified by positive CSF PCR for JC virus or histopathology between January 1, 1994, and January 1, 2019. Demographic and PML-specific variables were recorded on symptomatic presentation and at follow-up, including risk factors, clinical outcome, neuroimaging findings, and modified Rankin Scale (mRS) score at last follow-up.

RESULTS

There were 91 patients with confirmed PML. HIV infection was the most common risk factor, identified in 49% (n = 45). Other frequent risk factors included lymphoma, leukemia, or myelodysplasia, identified in 31% of patients (n = 28); exposure to chemotherapeutic medications (30%, n = 27); and exposure to monoclonal antibody therapies (19%, n = 17). Thirty percent of the cohort was alive at the time of censoring, with a median mRS of 2 points, indicating slight disability at last follow-up. Median survival following PML diagnosis in HIV-infected patients was longer than in HIV-uninfected patients (1,992 vs 101 days, p = 0.024). Forty patients survived more than 1 year after PML symptom onset, of whom 24 were HIV infected (60%). Thirteen patients survived more than 10 years after PML symptom onset, all HIV infected, of the 59 patients diagnosed before June 1, 2009, and eligible for 10-year survivor status (22%).

CONCLUSIONS

We add to the limited literature on PML by reporting its epidemiology in a large observational cohort. These parameters may be useful for future clinical trials that measure survival and clinical outcomes.

Quality of life in epilepsy-31 inventory (QOLIE-31) scores: A global comparison

Quality of life is a pragmatic endpoint for understanding the experience of people with epilepsy (PWE) in low- and middle-income countries (LMICs), where>80% of PWE reside. However, the literature is bereft of QOL in epilepsy (QOLIE) studies among LMICs and knowledge of the variation in QOLIE globally. We therefore performed a Medline search of original research studies using the quality of life in epilepsy-31 inventory (QOLIE-31) in a recent fifteen-year period (2000-2015). Each of the 194 countries listed by the World Health Organization (WHO) was individually included as search terms. Differences in QOLIE were tested across WHO world regions and World Bank country income group classifications. Sixteen percent of all countries (n=31) reported on 7255 individuals, including only 8 LMICs. The global mean QOLIE-31 score was 59.8 (standard deviation (SD): 8.0), with a range from 42.1 (SD: 4.1) in the Russian Federation to 82 (SD: 32.8) in Canada. There was a statistically significant difference seen in the QOLIE-31 score by world region and income category, with lower country income level associated with worse QOL (test for trend, p<0.0001). There exists substantial global variation in QOLIE, and country income level may play a role. Understanding what contributes to international differences in QOLIE can help reduce disparities in QOL among PWE worldwide.

Impact of the COVID-19 pandemic on the health care of >1,000 People living with multiple sclerosis: A cross-sectional study

BACKGROUND

People with multiple sclerosis (PwMS) experienced changes in health behaviors and access to MS care due to the COVID-19 pandemic. The USA has the highest recognized number of Covid19 infections globally. The extent of the impact of COVID-19 has not been well characterized in large samples of PwMS to date. The MS patient perspective on COVID-19 would complement the physician-reported cases of MS and COVID-19 in the literature.

METHODS

A cross-sectional survey of adult PwMS was performed online, using the U.S.-based patient-powered iConquerMS™ platform, in April 2020.

RESULTS

There were 1,145 respondents (response rate: 20%). 1,019 had a diagnosis of MS and responded completely (average age: 54.2 years, range: 20-81; 79% female; 64% relapsing remitting, 22% secondary progressive, 12% primary progressive; 88% in the USA). 748 (73%) used a DMT in the last year, primarily higher-efficacy therapies: ocrelizumab (n=238), dimethyl fumarate (n=85), fingolimod (n=80). The most frequent comorbidities were depression (41%), hypertension (26%), and asthma (12%). Women were more worried than men about COVID-19 (p=0.001); non-white-identifying PwMS believed it was a greater danger to their health than white-identifying PwMS (p=0.002). Through the continuum of symptoms to care, 61% of PwMS (n=617) reported symptoms associated with COVID-19, 39% (n=395) knew someone exposed to COVID-19, 4% (n=38) were aware of a personal COVID-19 exposure, 13% (n=128) wanted testing for COVID-19 but could not access it, and 4% (n=43) were tested. Specific to their MS care, 64% (n=650) canceled a medical visit, 22% (n=222) canceled a neurologist visit, 11% (n=112) canceled an MRI, 21% (n=212) canceled a laboratory test, and 10% (n=98) changed their DMT in some way due to COVID19 including 65 delaying at least one dose. 37% (n=382) had a telehealth visit due to COVID-19. 37% of PwMS (n=374) experienced employment changes, most commonly working from home (n=194) and having work hours reduced (n=65) while 32 lost their jobs. Of the 7 cases who tested positive for COVID-19 (<1% of participants) (5 female; age range: 29-64 years), DMTs included dimethyl fumarate (n=2), ocrelizumab (n=1), rituximab (n=1), and a clinical trial drug (n=1).

CONCLUSIONS

A majority of people with MS reported interruptions to their MS care along the MS care pathway alongside limited access to COVID-19 testing. Postponements and delays in care were common with 10% of participants reporting a change in their DMT administration. Less than 1% of this self-referred convenience online cohort had a positive test for COVID-19 although more than half reported symptoms that are associated with COVID-19.

OASIS is Automated Statistical Inference for Segmentation, with applications to multiple sclerosis lesion segmentation in MRI

Magnetic resonance imaging (MRI) can be used to detect lesions in the brains of multiple sclerosis (MS) patients and is essential for diagnosing the disease and monitoring its progression. In practice, lesion load is often quantified by either manual or semi-automated segmentation of MRI, which is time-consuming, costly, and associated with large inter- and intra-observer variability. We propose OASIS is Automated Statistical Inference for Segmentation (OASIS), an automated statistical method for segmenting MS lesions in MRI studies. We use logistic regression models incorporating multiple MRI modalities to estimate voxel-level probabilities of lesion presence. Intensity-normalized T1-weighted, T2-weighted, fluid-attenuated inversion recovery and proton density volumes from 131 MRI studies (98 MS subjects, 33 healthy subjects) with manual lesion segmentations were used to train and validate our model. Within this set, OASIS detected lesions with a partial area under the receiver operating characteristic curve for clinically relevant false positive rates of 1% and below of 0.59% (95% CI; [0.50%, 0.67%]) at the voxel level. An experienced MS neuroradiologist compared these segmentations to those produced by LesionTOADS, an image segmentation software that provides segmentation of both lesions and normal brain structures. For lesions, OASIS out-performed LesionTOADS in 74% (95% CI: [65%, 82%]) of cases for the 98 MS subjects. To further validate the method, we applied OASIS to 169 MRI studies acquired at a separate center. The neuroradiologist again compared the OASIS segmentations to those from LesionTOADS. For lesions, OASIS ranked higher than LesionTOADS in 77% (95% CI: [71%, 83%]) of cases. For a randomly selected subset of 50 of these studies, one additional radiologist and one neurologist also scored the images. Within this set, the neuroradiologist ranked OASIS higher than LesionTOADS in 76% (95% CI: [64%, 88%]) of cases, the neurologist 66% (95% CI: [52%, 78%]) and the radiologist 52% (95% CI: [38%, 66%]). OASIS obtains the estimated probability for each voxel to be part of a lesion by weighting each imaging modality with coefficient weights. These coefficients are explicit, obtained using standard model fitting techniques, and can be reused in other imaging studies. This fully automated method allows sensitive and specific detection of lesion presence and may be rapidly applied to large collections of images.

Detection and localization of early- and late-stage cancers using platelet RNA

Cancer patients benefit from early tumor detection since treatment outcomes are more favorable for less advanced cancers. Platelets are involved in cancer progression and are considered a promising biosource for cancer detection, as they alter their RNA content upon local and systemic cues. We show that tumor-educated platelet (TEP) RNA-based blood tests enable the detection of 18 cancer types. With 99% specificity in asymptomatic controls, thromboSeq correctly detected the presence of cancer in two-thirds of 1,096 blood samples from stage I-IV cancer patients and in half of 352 stage I-III tumors. Symptomatic controls, including inflammatory and cardiovascular diseases, and benign tumors had increased false-positive test results with an average specificity of 78%. Moreover, thromboSeq determined the tumor site of origin in five different tumor types correctly in over 80% of the cancer patients. These results highlight the potential properties of TEP-derived RNA panels to supplement current approaches for blood-based cancer screening.

Neurological complications following adult lung transplantation

The full spectrum of neurologic complications and their impact on survival in lung recipients has not been reported. A retrospective cohort review of the Mayo Clinic Lung Transplant Registry (1988-2008) was performed to determine the range of neurologic complications in a cohort of adult lung recipients. Cox regression models were used to assess risk factors for neurological complications and death posttransplant. One hundred and twenty lung transplant recipients (53% women, median age at transplantation 53 years, range 21-73, median survival 4.8 years) were identified, of whom 95 had a neurological complication posttransplantation (median time to complication 0.8 years). Neurological complications were severe in 46 patients (requiring hospitalization or urgent care and evaluation) and were most often perioperative stroke or encephalopathy. Age predicted neurological complications of any type, whereas lung allocation score, bilateral lung transplantation, sex, underlying lung disease, elevated hemoglobin A1C, renal insufficiency and smoking history did not. Neurological complications of any severity (HR 4.3, 95% CI 2.2-8.6, p < 0.001) and high severity (HR 7.2, 95% CI 3.5-14.6, p < 0.001) were associated with increased risk of death. Neurological complications are common after lung transplantation, affecting 92% of recipients within 10 years. Severe neurologic complications are also common, affecting 53% of recipients within 10 years.