Am Fam Physician. 1999;60(6):1791-1792
New Test May Help in the Early Diagnosis of Alzheimer's Disease
(51st Annual Meeting of the American Academy of Neurology) A new modification of the magnetic resonance imaging (MRI) test, called functional MRI, can help in the early diagnosis of patients with mild memory impairment in the early stages of Alzheimer's disease, according to a study of subjects selected from a long-term, community-based aging project. This noninvasive technique can show dysfunction in the brain's entorhinal region of the hippocampus, the brain's key structure for controlling memory. The investigators note that early Alzheimer's disease targets the entorhinal region of the brain, causing dysfunction. None of the subjects had been diagnosed with dementia, Parkinson's disease, stroke or depression. Neurologic and neuropsychologic testing included evaluation of attention, orientation, memory, language ability and abstract reasoning. Among the 13 subjects with age-related memory decline, the functional MRI test revealed that five had entorhinal dysfunction and eight had normal entorhinal activity. Those with dysfunction also had greater decline over time in abstract reasoning and language function. The investigators believe that patients with dysfunction in the entorhinal region of the brain have early Alzheimer's disease, while those with age-related memory decline have dysfunction in different regions of the hippocampus.—scott small, m.d., et al., Sergievsky Center and Columbia Presbyterian Medical Center, New York City.
Moderate Alcohol Consumption May Lower Risk of Ischemic Stroke
(American Academy of Neurology) Results of a study of over 22,000 male physicians have shown that consumption of a small or moderate amount of alcohol every week can reduce the risk of ischemic stroke. Data for the study were taken from the Physicians' Health Study, which collected data on 22,071 physicians for an average of 12 years. During that time, 679 of the study participants had a stroke. Participants in the study who consumed from one drink a week to less than two drinks every day were 20 percent less likely to have a stroke than participants who never drank or who had less than one drink per week. The consumption of alcohol had no effect on hemorrhagic stroke. The investigators caution that the study's finding cannot be easily applied to the general population because the physicians overall had fewer risk factors for stroke than the general population.—klaus berger, m.d., m.p.h., et al., University of Muenster, Germany.
Zonisamide May Help Patients with Medication-Resistant Epilepsy
(American Academy of Neurology) Zonisamide (Zonegran), a drug under investigation in the United States, appears to be effective in the treatment of patients with epilepsy who have not responded to an antiepileptic drug, according to a U.S. study of eight patients with medication-resistant epilepsy who participated in a series of long-term trials of zonisamide. All of the patients had partial seizures that were inadequately controlled by a number of antiepileptic drugs before starting the trial of zonisamide. The patients in the study received zonisamide from 9.7 to 12.2 years (mean treatment duration: 11.0 years). The dosage ranged from 100 to 1,000 mg daily (mean: 500 to 700 mg daily). The most common side effects were ataxia, viral illness, dizziness, and forgetfulness or slowness of thought. Adverse events occurred most often during the initiation of therapy and became less frequent or less severe over time. The investigators believe that most patients with medication-resistant epilepsy will benefit from a total dosage of about 400 mg daily.—mark l. scheuer, m.d., et al., Comprehensive Epilepsy Center, University of Pittsburgh, Pittsburgh, Pa.
Botulinum Toxin May Help Children with Cerebral Palsy Use Their Legs
(American Academy of Neurology) Results of a study involving children with cerebral palsy indicate that injections of botulinum toxin may help children with cerebral palsy regain the use of their legs. The study included 27 children who ranged in age from two years to seven years. The children were unable to walk or to stand upright. Small doses of botulinum toxin were injected into the calves of the children at three- to four-month intervals during the three-year study. All of the children had improved muscle function beginning three to six months after receiving the injections. Six children were able to stand upright for the first time. The investigators note that the treatment was most effective when used in combination with physical therapy.—peter kanovsky, m.d., et al., Masaryk University, Brno, Czech Republic.
Study Shows Link Between Snoring and Hypertension in Pregnancy
(American Lung Association/American Thoracic Society 1999 International Conference) Partial upper airway obstruction may be responsible for an increase in blood pressure during the night in patients who have preeclampsia during pregnancy, according to results of a study conducted in Australia. The study included 21 pregnant women with severe preeclampsia and 10 women with a normal pregnancy. The women underwent sleep tests and continuous blood pressure recordings. Snoring and partial upper airway obstruction occurred in all of the women with preeclampsia during all stages of sleep. Their blood pressure increased steadily during the night. A subgroup of six patients received nasal continuous positive airway pressure (CPAP), which markedly reduced blood pressure in all stages of sleep. The investigators believe partial airway obstruction may result in increased nighttime blood pressure in women with preeclampsia and that nasal CPAP will help control hypertension in these women.—natalie edwards, m.d., et al., Australia.
Linezolid Shows Promise in Treatment of Pneumonia
(American Lung Association/American Thoracic Society) Results of an open-label, phase II, dosage-comparison study indicate that linezolid (Zyvox) is effective in the treatment of community-acquired pneumonia that is caused by Streptococcus pneumoniae. Linezolid is the first in a new class of antibiotics called oxazolidinones. Of the 126 clinically evaluable patients who received an average of nine days of therapy, 73 were microbiologically evaluable. The patients received either a low dose (250 mg three times a day or 375 mg twice a day) or a high dose (375 mg three times a day or 625 mg twice a day). The overall success rate was 96.4 percent at long-term follow-up (15 to 28 days after the end of therapy) in the patients receiving either a high dose (38 patients) or a low dose (18 patients) of linezolid. Results from 17 patients were indeterminate. The most common side effects were headache, nausea and diarrhea; these symptoms were usually mild to moderate. In phase III clinical trials, linezolid is being given in 400-mg and 600-mg dosages.—s.k. cammarata, m.d., et al., Clinical Development Infectious Diseases, Pharmacia & Upjohn, Inc., Kalamazoo, Mich.