The American journal of medicine
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Due to the growing awareness of exercise-related arrhythmias and improved sensitivity of diagnostic modalities, physicians are increasingly faced with choices that may have life-changing impact for the athlete. This article surveys recent research and expert opinion addressing benign and pathogenic cardiac changes underlying arrhythmias in athletes.
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Comparative effectiveness research (CER) may be defined informally as an assessment of available options for treating specific medical conditions in selected groups of patients. In this context, the most prominent features of CER are the various patient populations, medical ailments, and treatment options involved in any particular project. Yet, each research investigation also has a corresponding study design or "architecture," and in patient-oriented research a common distinction used to describe such designs are randomized controlled trials (RCTs) versus observational studies. The purposes of this overview, with regard to CER, are to (1) understand how observational studies can provide accurate results, comparable to RCTs; (2) recognize strategies used in selected newer methods for conducting observational studies; (3) review selected observational studies from the Veterans Health Administration; and (4) appreciate the importance of fundamental methodological principles when conducting or evaluating individual studies.
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Drug-induced osteoporosis is common and has a significant impact on the prognosis of patients suffering from chronic debilitating diseases. Glucocorticoids are the drugs causing osteoporotic fractures most frequently, but osteoporosis with fractures is observed also in women treated with aromatase inhibitors for breast cancer, in men receiving anti-androgen therapy for prostate cancer, in postmenopausal women treated with high doses of thyroxine, and in men and women treated with thiazolinediones for type 2 diabetes mellitus. Bone loss with fractures also occurs in patients treated with drugs targeting the immune system, such as calcineurin inhibitors, antiretroviral drugs, selective inhibitors of serotonin reuptake, anticonvulsants, loop diuretics, heparin, oral anticoagulants, and proton pump inhibitors.
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Statins reduce cardiovascular events and cardiovascular and total mortality in persons at risk for and with coronary disease, but there remains a significant residual event rate, particularly in those with the atherogenic lipid phenotype that is characterized by a low high-density lipoprotein (HDL) cholesterol and increase in non-HDL cholesterol. Large outcome trials designed to assess the value of combining statins with other agents to target HDL cholesterol and non-HDL cholesterol will not be completed for a few years, but there is ample evidence for the clinician to consider combination therapy. The choices for therapies to supplement statins include niacin, fibrates, and omega-3 fatty acids. ⋯ Evidence supports the addition of niacin as the second agent. In some situations, high-dose omega-3 fatty acid therapy could be the first agent added to statins. Although fibrate monotherapy alone or in combination with non-statin low-density lipoprotein cholesterol-lowering agents can be effective in mixed hyperlipidemia when statins are not tolerated, the combination of statin+fibrate should be considered second-line therapy until the efficacy and safety are established.
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Review Case Reports
Adult nonhepatic hyperammonemia: a case report and differential diagnosis.
This article presents a case report of nonhepatic hyperammonemia, i.e., elevated serum ammonia secondary to a nonhepatic etiology. It then discusses the importance of broadening one's differential diagnosis to include such nonhepatic causes of elevated ammonia levels, and provides a short review of rarer causes of hyperammonemia in the adult population. Treating the underlying condition is the best way to prevent recurrence of hyperammonemia. However, symptomatic treatment should not be delayed while investigating the underlying source.