Plateauing atrial fibrillation burden in acute ischemic stroke admissions in the United States from 2010 to 2020.

BACKGROUND: Utilization of oral anticoagulants for acute ischemic stroke (AIS) prevention in patients with atrial fibrillation (AF) increased in the United States over the last decade. Whether this increase has been accompanied by any change in AF prevalence in AIS at the population level remains unknown. The aim of this study is to evaluate trends in AF prevalence in AIS hospitalizations in various age, sex, and racial subgroups over the last decade. METHODS: We used data contained in the 2010-2020 National Inpatient Sample to conduct a serial cross-sectional study. Primary AIS hospitalizations with and without comorbid AF were identified using International Classification of Diseases Codes. Joinpoint regression was used to compute annualized percentage change (APC) in prevalence and to identify points of change in prevalence over time. RESULTS: Of 5,190,148 weighted primary AIS hospitalizations over the study period, 25.1% had comorbid AF. The age- and sex-standardized prevalence of AF in AIS hospitalizations increased across the entire study period 2010-2020 (average APC: 1.3%, 95% confidence interval (CI): 0.8-1.7%). Joinpoint regression showed that prevalence increased in the period 2010-2015 (APC: 2.8%, 95% CI: 1.9-3.9%) but remained stable in the period 2015-2020 (APC: -0.3%, 95% CI: -1.0 to 1.9%). Upon stratification by age and sex, prevalence increased in all age/sex groups from 2010 to 2015 and continued to increase throughout the entire study period in hospitalizations in men 18-39 years (APC: 4.0%, 95% CI: 0.2-7.9%), men 40-59 years (APC: 3.4%, 95% CI: 1.9-4.9%) and women 40-59 years (APC: 4.4%, 95% CI: 2.0-6.8%). In contrast, prevalence declined in hospitalizations in women 60-79 (APC: -1.0%, 95% CI: -0.5 to -1.5%) and women ⩾ 80 years over the period 2015-2020 but plateaued in hospitalizations in similar-aged men over the same period. CONCLUSION: AF prevalence in AIS hospitalizations in the United States increased over the period 2010-2015, then plateaued over the period 2015-2020 due to declining prevalence in hospitalizations in women ⩾ 60 years and plateauing prevalence in hospitalizations in men ⩾ 60 years.

Demographic Disparities in the Incidence, Clinical Characteristics, and Outcome of Posterior Reversible Encephalopathy Syndrome in the United States.

OBJECTIVES: To estimate age-specific, sex-specific, and race-specific incidence of posterior reversible encephalopathy syndrome (PRES) in the United States. METHODS: We conducted a retrospective cohort study using the State Inpatient Database of Florida (2016-2019), Maryland (2016-2019), and New York (2016-2018). All new cases of PRES in adults (18 years or older) were combined with Census data to compute incidence. We evaluated the generalizability of incident estimates to the entire country using the 2016-2019 National Readmissions Database (NRD). RESULTS: Across the study period, there were 3,716 incident hospitalizations for PRES in the selected states. The age-standardized and sex-standardized incidence of PRES was 2.7 (95% CI 2.5-2.8) cases/100,000/y. Incidence in female patients was >2 times that of male patients (3.7 vs 1.6 cases/100,000/y, p < 0.001). Incidence increased with age in both sexes (p-trend <0.001). Similar demographic distribution of first hospitalization for PRES was also noted in the entire country using the NRD. Age-standardized and sex-standardized PRES incidence in Black patients (4.2/100,000/y) was significantly greater than in Non-Hispanic White (2.7/100,000/y) and Hispanic patients (1.2/100,000/y) (p < 0.001 for pairwise comparisons). DISCUSSION: The incidence of PRES in the United States is approximately 3/100,000/y, but incidence in female patients is >2 times that of male patients. PRES incidence is higher in Black compared with non-Hispanic White and Hispanic patients.

Trends in the Incidence of Spontaneous Subarachnoid Hemorrhages in the United States, 2007-2017.

BACKGROUND AND OBJECTIVE: To test the hypothesis that age-specific, sex-specific, and race-specific and ethnicity-specific incidence of nontraumatic subarachnoid hemorrhage (SAH) increased in the United States over the last decade. METHODS: In this retrospective cohort study, validated International Classification of Diseases codes were used to identify all new cases of SAH (n = 39,475) in the State Inpatients Databases of New York and Florida (2007-2017). SAH counts were combined with Census data to calculate incidence. Joinpoint regression was used to compute the annual percentage change (APC) in incidence and to compare trends over time between demographic subgroups. RESULTS: Across the study period, the average annual age-standardized/sex-standardized incidence of SAH in cases per 100,000 population was 11.4, but incidence was significantly higher in women (13.1) compared with that in men (9.6), p < 0.001. Incidence also increased with age in both sexes (men aged 20-44 years: 3.6; men aged 65 years or older: 22.0). Age-standardized and sex-standardized incidence was greater in Black patients (15.4) compared with that in non-Hispanic White (NHW) patients (9.9) and other races and ethnicities, p < 0.001. On joinpoint regression, incidence increased over time (APC 0.7%, p < 0.001), but most of this increase occurred in men aged 45-64 years (APC 1.1%, p = 0.006), men aged 65 years or older (APC 2.3%, p < 0.001), and women aged 65 years or older (APC 0.7%, p = 0.009). Incidence in women aged 20-44 years declined (APC -0.7%, p = 0.017), while those in other age/sex groups remained unchanged over time. Incidence increased in Black patients (APC 1.8%, p = 0.014), whereas that in Asian, Hispanic, and NHW patients did not change significantly over time. DISCUSSION: Nontraumatic SAH incidence in the United States increased over the last decade predominantly in middle-aged men and elderly men and women. Incidence is disproportionately higher and increasing in Black patients, whereas that in other races and ethnicities did not change significantly over time.

Age-specific trends in intravenous thrombolysis and mechanical thrombectomy utilization in acute ischemic stroke in children under age 18.

OBJECTIVES: To evaluate current trends in the utilization of intravenous thrombolysis (IV-tPA) and mechanical thrombectomy (MT) in acute ischemic stroke (AIS) in various age groups of children in the United States. METHODS: We conducted a serial cross-sectional study using primary AIS admissions in children ⩽ 17 years (weighted n = 2807) contained in the 2009-2019 KIDS Inpatient Database. Age-specific utilization frequency of IV-tPA and MT were calculated. Multivariable-adjusted models were used to evaluate demographic predictors of treatment. RESULTS: From 2009 to 2019, there were 2807 AIS admissions in children in the KID of which 55.9% were in boys and 29.9% were 15-17 years old.128 (4.6%) received IV-tPA. IV-tPA utilization differed by age (5-9 years: 3.1%, 15-17 years 8.1% p value < 0.001). Overall MT usage was 2.3% and this also varied by age (1-4 years: 0.9% and 15-17years 4.0%, p value = 0.006). IV-tPA utilization almost tripled across the study period (2.5% 2009 to 6.5% in 2019, p value = 0.001) while MT use more than doubled over time (1.2% in 2009 and 3.0% in 2019, p value = 0.048). Increased IV-tPA utilization was seen primarily in children 10-14 years (0.8% in 2009 to 7.2% 2019, p value = 0.005) and 15-17 years (5.4% in 2009 to 10.4% in 2019, p value = 0.045). Utilization in younger age groups remained unchanged over time. MT usage was very variable across various age groups over time. IV-tPA and MT utilization increased over time in nonchildren's hospitals (both p values < 0.05) but usage in designated children's hospitals did not change significantly over time. In multivariable models, there was no significant difference in odds of IV-tPA and MT use by sex, race or insurance status. CONCLUSION: IV-tPA and MT utilization in pediatric AIS increased in the United States over the past decade mainly in older children 10-17 years. Utilization increased mainly in patients hospitalized in nonchildren's hospitals. Usage in children's hospitals did not change significantly over time.

Nimodipine in Clinical Practice: A Pharmacological Update.

ABSTRACT: INTRODUCTION: Enteral nimodipine provides a neuroprotective effect in patients who have experienced an aneurysmal subarachnoid hemorrhage (aSAH). Nimodipine remains the only US Food and Drug Administration-approved medication for aSAH. CONTENT: Nimodipine has been prescribed for patients with aSAH; however, little is known about factors to consider regarding dosing or patient-specific variables that may affect tolerability to nimodipine. Clinical impact of dose or dosing frequency changes has also been much debated based on risk of hypotension with currently approved dosing regimens. CONCLUSION: This review article addresses factors to consider for dosing and administration, pharmacokinetic and pharmacogenetic impact on nimodipine, and, finally, drug interaction considerations to assess as patients are initiated on enteral nimodipine for aSAH.

Targeting SR proteins improves SMN expression in spinal muscular atrophy cells.

Spinal muscular atrophy (SMA) is one of the most common inherited causes of pediatric mortality. SMA is caused by deletions or mutations in the survival of motor neuron 1 (SMN1) gene, which results in SMN protein deficiency. Humans have a centromeric copy of the survival of motor neuron gene, SMN2, which is nearly identical to SMN1. However, SMN2 cannot compensate for the loss of SMN1 because SMN2 has a single-nucleotide difference in exon 7, which negatively affects splicing of the exon. As a result, most mRNA produced from SMN2 lacks exon 7. SMN2 mRNA lacking exon 7 encodes a truncated protein with reduced functionality. Improving SMN2 exon 7 inclusion is a goal of many SMA therapeutic strategies. The identification of regulators of exon 7 inclusion may provide additional therapeutic targets or improve the design of existing strategies. Although a number of regulators of exon 7 inclusion have been identified, the function of most splicing proteins in exon 7 inclusion is unknown. Here, we test the role of SR proteins and hnRNP proteins in SMN2 exon 7 inclusion. Knockdown and overexpression studies reveal that SRSF1, SRSF2, SRSF3, SRSF4, SRSF5, SRSF6, SRSF7, SRSF11, hnRNPA1/B1 and hnRNP U can inhibit exon 7 inclusion. Depletion of two of the most potent inhibitors of exon 7 inclusion, SRSF2 or SRSF3, in cell lines derived from SMA patients, increased SMN2 exon 7 inclusion and SMN protein. Our results identify novel regulators of SMN2 exon 7 inclusion, revealing potential targets for SMA therapeutics.

The DcpS inhibitor RG3039 improves motor function in SMA mice.

Spinal muscular atrophy (SMA) is caused by mutations of the survival motor neuron 1 (SMN1) gene, retention of the survival motor neuron 2 (SMN2) gene and insufficient expression of full-length survival motor neuron (SMN) protein. Quinazolines increase SMN2 promoter activity and inhibit the ribonucleic acid scavenger enzyme DcpS. The quinazoline derivative RG3039 has advanced to early phase clinical trials. In preparation for efficacy studies in SMA patients, we investigated the effects of RG3039 in severe SMA mice. Here, we show that RG3039 distributed to central nervous system tissues where it robustly inhibited DcpS enzyme activity, but minimally activated SMN expression or the assembly of small nuclear ribonucleoproteins. Nonetheless, treated SMA mice showed a dose-dependent increase in survival, weight and motor function. This was associated with improved motor neuron somal and neuromuscular junction synaptic innervation and function and increased muscle size. RG3039 also enhanced survival of conditional SMA mice in which SMN had been genetically restored to motor neurons. As this systemically delivered drug may have therapeutic benefits that extend beyond motor neurons, it could act additively with SMN-restoring therapies delivered directly to the central nervous system such as antisense oligonucleotides or gene therapy.

Increased IGF-1 in muscle modulates the phenotype of severe SMA mice.

Spinal muscular atrophy (SMA) is an inherited motor neuron disease caused by the mutation of the survival motor neuron 1 (SMN1) gene and deficiency of the SMN protein. Severe SMA mice have abnormal motor function and small, immature myofibers early in development suggesting that SMN protein deficiency results in retarded muscle growth. Insulin-like growth factor 1 (IGF-1) stimulates myoblast proliferation, induces myogenic differentiation and generates myocyte hypertrophy in vitro and in vivo. We hypothesized that increased expression of IGF-1 specifically in skeletal muscle would attenuate disease features of SMAΔ7 mice. SMAΔ7 mice overexpressing a local isoform of IGF-1 (mIGF-1) in muscle showed enlarged myofibers and a 40% increase in median survival compared with mIGF-1-negative SMA littermates (median survival = 14 versus 10 days, respectively, log-rank P = 0.025). Surprisingly, this was not associated with a significant improvement in motor behavior. Treatment of both mIGF-1(NEG) and mIGF-1(POS) SMA mice with the histone deacetylase inhibitor, trichostatin A (TSA), resulted in a further extension of survival and improved motor behavior, but the combination of mIGF-1 and TSA treatment was not synergistic. These results show that increased mIGF-1 expression restricted to muscle can modulate the phenotype of SMA mice indicating that therapeutics targeted to muscle alone should not be discounted as potential disease-modifying therapies in SMA. IGF-1 may warrant further investigation in mild SMA animal models and perhaps SMA patients.

The genetics of spinal muscular atrophies.

PURPOSE OF REVIEW: This article reviews clinical, genetic, and therapeutic advances in spinal muscular atrophies (SMAs), inherited disorders characterized by motor neuron loss and muscle weakness. RECENT FINDINGS: There has been progress in defining the clinical and genetic features of at least 16 distinct forms of SMA. The genes associated with 14 of these disorders have been identified in the last decade, including four within the last year: TRPV4, ATP7A, VRK1, and HSPB3. Genetic testing is now available for many SMAs, providing important diagnostic and prognostic information. Cell and animal models of SMAs have been used to further understand how mutations in SMA-associated genes, which code for proteins involved in diverse functions such as transcriptional regulation, RNA processing, and cytoskeletal dynamics, lead to motor neuron dysfunction and loss. In the last year, there has also been remarkable progress in preclinical therapeutics development for proximal SMA using gene therapy, antisense oligonucleotides, and small molecules. SUMMARY: The advances in the clinical and genetic characterization of different forms of SMAs have important implications for clinical evaluation and management of patients. The identification of multiple, novel SMA-causing genes will lead to an improved understanding of motor neuron disease biology and may provide novel targets for therapeutics development.

Inhibition of myostatin does not ameliorate disease features of severe spinal muscular atrophy mice.

There is currently no treatment for the inherited motor neuron disease, spinal muscular atrophy (SMA). Severe SMA causes lower motor neuron loss, impaired myofiber development, profound muscle weakness and early mortality. Myostatin is a transforming growth factor-beta family member that inhibits muscle growth. Loss or blockade of myostatin signaling increases muscle mass and improves muscle strength in mouse models of primary muscle disease and in the motor neuron disease, amyotrophic lateral sclerosis. In this study, we evaluated the effects of blocking myostatin signaling in severe SMA mice (hSMN2/delta7SMN/mSmn(-/-)) by two independent strategies: (i) transgenic overexpression of the myostatin inhibitor follistatin and (ii) post-natal administration of a soluble activin receptor IIB (ActRIIB-Fc). SMA mice overexpressing follistatin showed little increase in muscle mass and no improvement in motor function or survival. SMA mice treated with ActRIIB-Fc showed minimal improvement in motor function, and no extension of survival compared with vehicle-treated mice. Together these results suggest that inhibition of myostatin may not be a promising therapeutic strategy in severe forms of SMA.