Omar K. Siddiqi

Trends in hospitalizations for adults with congenital heart disease in the U.S.

OBJECTIVES The purpose of this study was to better define the epidemiology of hospitalizations for adults with congenital heart disease (ACHD) in the U.S. BACKGROUND There is a growing population of ACHD as the result of advances in pediatric care and diagnostic testing. METHODS We used nationally representative data from the 1998 to 2005 Nationwide Inpatient Sample to identify patients > or =18 years of age admitted to an acute care hospital with an International Classification of Diseases-9th Revision code designating a CHD diagnosis. National estimates of hospitalizations and total hospital charges by year were calculated. RESULTS The number of ACHD hospitalizations increased 101.9% from 35,992 +/- 2,645 in 1998 to 72,656 +/- 5,258 in 2005. During this period, the annual number of admissions grew for both simple (19,448 +/- 1,614 to 44,707 +/- 3,644) and complex (12,507 +/- 1,172 to 19,973 +/- 1,624) diagnoses. The percentage of admissions originating in the emergency department (41.7 +/- 0.8%) or involving cardiac surgery (17.7 +/- 0.7%) remained stable during the study period. The average patient age (52.3 +/- 0.8 years to 53.8 +/- 0.6 years, p < 0.0001) and proportion of patients with > or =2 medical comorbidities (23.3 +/- 0.9% to 33.0 +/- 0.7%, p < 0.0001) increased. Mean hospital charges per hospitalization increased 127% from 19,186 +/- 803 to 43,496 +/- 2,166 US dollars, and the estimated total national charges for these hospitalizations increased 357% from 691 million US dollars in 1998 to 3.16 billion US dollars in 2005 (in inflation-adjusted 2005 dollars). CONCLUSIONS The number of hospital admissions for ACHD in the U.S. more than doubled between 1998 and 2005. Hospital charges attributable to these admissions have grown even more dramatically.

Maternal cardiovascular events during childbirth among women with congenital heart disease

Objectives To define the epidemiology of adverse cardiovascular events among women with congenital heart disease (CHD) hospitalised for childbirth in the USA. Design and setting The 1998–2007 Nationwide Inpatient Sample, an administrative dataset representative of overall US hospital admissions, was used to identify hospitalisations for delivery. Main outcome measures Logistic regression was used to estimate ORs for cardiovascular outcomes (arrhythmia, heart failure, cerebrovascular accident, embolism, death or a combined outcome) for women with and without CHD. Covariates included age, number of medical comorbidites, pulmonary hypertension, hospital teaching status, insurance status and method of delivery. Results Annual deliveries for women with CHD increased 34.9% from 1998 to 2007 compared with an increase of 21.3% in the general population. Women with CHD were more likely to sustain a cardiovascular event (4042/100 000 vs 278/100 000 deliveries, univariate OR 15.1, 95% CI 13.1 to 17.4, multivariable OR 8.4, 95% CI 7.0 to 10.0). Arrhythmia, the most common cardiovascular event, was more frequent among women with CHD (2637/100 000 vs 210/100 000, univariate OR 12.9, 95% CI 10.9 to 15.3, multivariable OR 8.3, 95% CI 6.7 to 10.1). Death occurred in 150/100 000 patients with CHD compared with 8.2/100 000 patients without CHD (multivariable OR 6.7, 95% CI 2.9 to 15.4). Complex CHD was associated with greater odds of having an adverse cardiovascular event than simple CHD (8158/100 000 vs 3166/100 000, multivariable OR 2.0, 95% CI 1.4 to 3.0). Conclusions Maternal CHD is associated with a markedly increased risk of adverse cardiovascular events and death during admission for delivery.

Very late stent thrombosis: current concepts.

Purpose of review Drug-eluting stents (DES) are effective in reducing neointimal proliferation and in-stent restenosis. However, the procedure is complicated by early and late stent thrombosis that is related to incomplete healing, leading to stent malapposition and incomplete reendothelialization. Stent restenosis results in significant mortality and morbidity and portends a poor long-term outcome. In this article, we review recent findings regarding the prevalence of late and very late stent thrombosis (VLST) and the mechanisms that may be at play. Recent findings Long-term follow-up from large registry studies and randomized controlled trials of DES implantation have recently created an awareness of the persistence of VLST (0.26%/year) for up to at least 5 years. Recent findings utilizing intravascular ultrasound and optical coherence tomography have also provided important insights into the mechanism of VLST and suggest that delayed healing and neoatherosclerosis are important. Finally, the development of novel stent scaffolds and antiplatelet agents holds much promise for reducing the risk of VLST. Summary DES implantation continues to be complicated by the risk of VLST. Recent insights into the mechanisms of this significant clinical problem have important implications in preventing VLST.

The spectrum of neurological disorders in a Zambian tertiary care hospital

OBJECTIVES To define the spectrum of inpatient and outpatient neurological illness in a Zambian tertiary care facility where HIV is endemic. METHODS A retrospective period prevalence study of patients seen by the consulting neurologist between 1/2/06-12/20/06 at the University of Zambias University Teaching Hospital (UTH). RESULTS 443 inpatients and 368 outpatients were seen during this period. Overall, 160 (19.7%) patients underwent HIV testing: 125 (15.4%) HIV(+) and 35 (4.3%) HIV(-). The other 651 (80.3%) patients were untested. The most common inpatient neurological diseases among HIV(+) patients were infectious diseases 26 (38.8%), neuropathy/radiculopathy 10 (10.4%), cerebrovascular disease 6 (9.0%), and myelopathy 5 (7.5%). The most common inpatient neurological diseases in the general population were cerebrovascular disease 62 (16.5%), infectious diseases 47 (12.5%), neuropathy/radiculopathy 37 (9.8%), and seizures/epilepsy 27 (7.2%). In the outpatient population, the most common neurological illnesses in HIV(+) patients were neuropathy/radiculopathy 18 (31.0%), cerebrovascular disease 8 (13.8%), dementia/neurodegenerative 8 (13.8%), and encephalopathy 7 (12.1%). Outpatients in the general population most commonly had headaches/cephalgias 60 (19.4%), movement disorders 47 (15.2%), neuropathy/radiculopathy 43 (13.8%), and seizures/epilepsy 39 (12.6%). CONCLUSIONS HIV-infected individuals are a sizeable group among neurology patients in Zambia, and they are affected by a different disease spectrum than the general population. Infectious diseases make up the largest percentage of inpatient neurological illness. Non-infectious causes are responsible for the majority of outpatient neurological cases. Emphasis should be placed on treatment of both infectious and non-infectious neurological illnesses. The most common outpatient neurological conditions are symptomatically treatable with routinely available medications.

Lumbar puncture refusal in sub-Saharan Africa: A call for further understanding and intervention

In 1891, Winter1 described the first 4 cases of tuberculous meningitis (TBM), in which “paracenteses of the theca vertebralis was performed to relieve cerebrospinal fluid (CSF) fluid pressure.” Since this original description of the lumbar puncture (LP) procedure, neurologists worldwide have relied on LPs for both diagnostic and therapeutic purposes. In resource-limited settings, LPs are often the only neurologic test available to aid the clinician in neurologic diagnosis. In sub-Saharan Africa, a large number of patients present to hospitals with acute neurologic symptoms, including those who are HIV-infected and have opportunistic infections such as cryptococcal meningitis and TBM. In these clinical scenarios, LPs are an essential point-of-care diagnostic and therapeutic procedure.2 The benefits of the LP as a diagnostic tool are well-known, but it is important to emphasize that therapeutic LPs are a low-cost measure to monitor and treat intracranial pressure (ICP) due to nonobstructive hydrocephalus in regions of the world where more sophisticated testing and treatment are unavailable due to limitations of medical equipment, medication supplies, and clinical personnel, including specialized neurologists and neurosurgeons.

Outcomes with prolonged clopidogrel therapy after coronary stenting in patients with chronic kidney disease

Objectives Patients with chronic kidney disease (CKD) are at high risk of death or myocardial infarction (MI) after percutaneous coronary interventions (PCI). We assessed whether prolonged dual antiplatelet therapy beyond the recommended 12 months may prevent adverse outcomes in patients with CKD receiving drug-eluting stents (DES) or bare-metal stents (BMS). Methods We studied all Veterans receiving PCI with BMS or first-generation DES in the Veterans Affairs (VA) Healthcare System between 2002 and 2006, classified by CKD (estimated glomerular filtration rate <60 mL/min) or normal renal function. We used landmark analyses from 12 months after PCI with Cox proportional hazards multivariable and propensity-adjusted models to assess the effect of prolonged clopidogrel (more than 12 months) versus 12 months or less after PCI on clinical outcomes from 1 year to 4 years after PCI. Results Of 23 042 eligible subjects receiving PCI, 4880 (21%) had CKD. Compared with normal renal function, patients with CKD had higher risks of death or MI 1–4 years after DES (21% vs 12%, HR=1.75; 95% CI 1.51 to 2.04) or BMS (28% vs 15%, HR=2.10; 95% CI 1.90 to 2.32). In patients with CKD receiving DES, clopidogrel use of more than 12 months after PCI was associated with lower risks of death or MI (18% vs 24%, HR=0.74; 95% CI 0.58 to 0.95), and death (15% vs 23%, HR=0.61; 95% CI 0.47 to 0.80), but had no effect on repeat revascularisation 1–4 years after PCI. Conclusions In patients with CKD, prolonging clopidogrel beyond 12 months after PCI may decrease the risk of death or MI only in patients receiving first-generation DES. These results support a patient-tailored approach to prolonging clopidogrel after PCI.

Safe Treatment of Seizures in the Setting of HIV/AIDS

Opinion statementHIV+ patients are at increased risk for developing seizures due to the vulnerability of the central nervous system to HIV-associated diseases, immune dysfunction, and metabolic disturbances. In patients with acute seizures, standard protocols still apply with urgent seizure cessation being the priority. Management of the person with established epilepsy who contracts HIV is challenging, but the decision to initiate chronic antiepileptic drug (AED) therapy in an HIV+ patient is also difficult. Chronic treatment guidelines emphasize the interactions between AEDs and antiretroviral (ARV) medications, but provide no explicit advice regarding when to initiate an AED, what medication to select, and/or the duration of treatment. Epidemiologic data regarding seizure recurrence risk in HIV+ individuals is not available. The risk of further seizures likely depends upon the underlying etiology for the seizure(s) and patients’ immune status and may be increased by the use of efavirenz (an ARV). The issues for consideration include AED-ARV interactions, organ dysfunction, seizure type, and drug side effects, which may worsen or be confused with symptoms of HIV and/or epilepsy. Co-administration of enzyme inducing (EI)-AEDs and ARVs can result in virological failure, breakthrough seizure activity, AED toxicity, and/or ARV toxicity. Where available, the AED of choice in HIV+ patients is levetiracetam due to its broad spectrum activity, ease of use, minimal drug interactions, and favorable side effect profile. Lacosamide, gabapentin, and pregabalin are also favored choices in patients with partial onset seizures and/or those failing levetiracetam. Where newer AEDs are not available, valproic acid may be the treatment of choice in terms of an AED, which will not cause enzyme induction-associated ARV failure, but its side effect profile causes other obvious problems. In resource-limited settings (RLS) where only EI-AEDs are available, there are no good treatment options and further pressure needs to be placed upon policymakers to address this care gap and public health threat.

Cardiac amyloidosis: An update on pathophysiology, diagnosis, and treatment

The amyloidoses are a group of systemic diseases characterized by organ deposition of misfolded protein fragments of diverse origins. The natural history of the disease, involvement of other organs, and treatment options vary significantly based on the protein of origin. In AL amyloidosis, amyloid protein is derived from immunoglobulin light chains, and most often involves the kidneys and the heart. ATTR amyloidosis is categorized as mutant or wild-type depending on the genetic sequence of the transthyretin (TTR) protein produced by the liver. Wild-type ATTR amyloidosis mainly involves the heart, although the reported occurrence of bilateral carpal tunnel syndrome, spinal stenosis and biceps tendon rupture in these patients speaks to more generalized protein deposition. Mutant TTR is marked by cardiac and/or peripheral nervous system involvement. Cardiac involvement is associated with symptoms of heart failure, and dictates the clinical course of the disease. Cardiac amyloidosis can be diagnosed noninvasively by echocardiography, cardiac MRI, or nuclear scintigraphy. Endomyocardial biopsy may be needed in the case of equivocal imaging findings or discordant data. Treatment is aimed at relieving congestive symptoms and targeting the underlying amyloidogenic process. This includes anti-plasma cell therapy in AL amyloidosis, and stabilization of the TTR tetramer or inhibition of TTR protein production in ATTR amyloidosis. Cardiac transplantation can be considered in highly selected patients in tandem with therapy aimed at suppressing the amyloidogenic process, and appears associated with durable long-term survival.

Emerging Subspecialties in Neurology: Global health

Global health is the study, research, and practice that places a priority on improving health and achieving equity in health for all people worldwide.1 In contrast to the public health concerns of a particular country or region, global health looks at populations irrespective of borders. One of the key elements in advancing the field of global health was the establishment of the WHO in 1948. Since its inception, the WHO has helped coordinate global efforts toward eradication of diseases such as smallpox and polio as well as elimination of onchocerciasis. It now assumes responsibility for the International Classification of Diseases. More recently, the field of global health has received considerable attention from world leaders, philanthropists, and academics. In 2009, President Obama introduced his Global Health Initiative that proposed spending

Acute EEG findings in HIV-infected Zambian adults with new-onset seizure

63 billion over 6 years to support global health programs specifically targeting areas such as HIV/AIDS, malaria, tuberculosis, nutrition, and reproductive health. On his first day of work as NIH Director, Francis Collins announced global health as one of his 5 themes of “exceptional opportunity” that would receive special priority during his tenure.2 The Fogarty International Center is a branch of the NIH that helps to support global health research for US and foreign researchers, often in resource-limited settings. The research initiatives encompass a diverse range of disciplines within the field of medicine.