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Generations of healers have believed in the therapeutic benefits of bed rest, including commentary by Hippocrates himself. Through the 1800s, with few efficacious tools at hand, bed rest was a primary treatment for many disorders. Contrary to this time-honored wisdom, consequences like DVT, osteoporosis, pressure sores, contractures, and atrophy have all been ascribed to bed rest. Only a few areas of medicine have specifically examined the role of bed rest as a therapeutic modality.
Allen and colleagues were able to identify 39 randomized trials referable to 15 different disorders such as bed rest for post-lumbar puncture, radiculography, cardiac catheterization, liver biopsy, low back pain, labor, threatened abortion, myocardial infarction, and rheumatoid arthritis.
Among 24 trials of bed rest after a medical procedure, none demonstrated significantly improved outcome, though a number did show statistically significantly worse outcome. Even in trials of spinal headache post-lumbar puncture, no significant benefit of bed rest was discernible. No benefit of bed rest is demonstrated for acute low back pain, myocardial infarction, tuberculosis, or hepatitis. Similarly, obstetrical trials not only show no improvement when bed rest is employed in first-stage labor, they actually show worse outcomes.
That bed rest is of questionable value has not seemed to effect change among clinicians. Seventeen years after the publication of a trial on the absence of benefit from bed rest after lumbar puncture, 80% of neurologists in the United Kingdom continued to insist upon the practice. Scientifically substantiated indications for bed rest remain to be defined.
Allen C, et al. Lancet 1999;354: 1229-1233.
Tuberculosis occurring many years after primary infection is called postprimary TB. Previous to the availability of DNA fingerprinting, it was unclear whether postprimary TB was a consequence of reactivation of endogenous primary disease or reinfection, though traditional opinion held that endogenous reactivation was the primary method. With currently available tools, it is now possible to discern whether postprimary TB is caused by the same strain that was etiologic for the primary infection or another strain.
The population studied, from Cape Town, South Africa, reflects a high number of cases of TB per year (1000 cases per 100,000 population per year). Subjects sustained at least two episodes of postprimary TB within a six-year period. These patients were all HIV negative, free from diabetes, end-stage renal disease, or other immunosuppressive disorder.
A different DNA pattern than had been causative of the primary infection was reported in 75% of postprimary TB cases. Twenty-five percent of postprimary TB involved drug-resistant strains, of which half were due to exogenous reinfection and half due to endogenous reactivation.
Since, in this population, most postprimary TB is a result of exogenous reinfection, van Rie and colleagues suggest additional emphasis on early case detection to prevent exposure to active disease in those with cured primary TB. It is unknown whether these data will be reflective of post-primary TB etiologies in settings with less prominent background disease rates, where opportunity of exposure to new active cases is substantially less.
van Rie A, et al. N Engl J Med 1999; 341:1174-1178.
As many as half of hiv-1 infected individuals treated with antiviral therapy may develop resistance. Contributing factors include serial monotherapy, uninhibited viral replication due to inadequate suppression by less than maximally effective agents, difficulty adhering to complicated regimens often associated with substantial burden of side effects, and therapy begun late in the course of the disease. Transmission of multidrug-resistant HIV-1 virus is a serious concern. To evaluate the demographics of this problem, Boden and associates evaluated mutations in 80 newly HIV-1 infected individuals who acquired the disease between July 1995 and April 1998; during this time, multidrug treatment of HIV had become the standard methodology.
More than 16% of samples analyzed demonstrated resistance to one or more antiretroviral agents and almost twice that number showed a three-fold or greater reduction in susceptibility to at least one retroviral agent. Only about 4% of samples demonstrated multidrug resistance.
Study subjects in this group came primarily from a population of urban homosexual men. Hence, demographics here described may not reflect other community settings and may not be applicable to women or heterosexual men. Boden et al suggest that clinical trials that evaluate potential virological and immunological benefits achieved by using resistance assay-guided therapeutic regimens are in order.
Boden D, et al. JAMA 1999;282: 1135-1141.