Clinical Briefs
With Comments from Russell H. Greenfield, MD, Dr. Greenfield is Medical Director, Carolinas Integrative Health, Carolinas HealthCare System, Charlotte, NC, and Clinical Assistant Professor, School of Medicine, University of North Carolina, Chapel Hill, NC.
Chicken a la Microbe: Food Safety
Source: Kieke AL, et al. Use of streptogramin growth promoters in poultry and isolation of streptogramin-resistant Enterococcus faecium from humans. J Infect Dis 2006;194:1200-1208.
Goal: To examine the relationship between poultry exposure and isolation of quinupristin-dalfopristin-resistant (QD-resistant) Enterococcus faecium from human digestive tracts.
Study design: Twelve-month epidemiologic, cross-sectional survey of the presence of QD-resistant E. faecium.
Subjects: Recently admitted hospitalized patients (n = 567) and healthy vegetarian volunteers (n = 100), all older than age 14, and readily available retail poultry, all within four communities in Wisconsin and Minnesota.
Methods: Vegetarian volunteers were recruited from local health-food cooperatives, and stool samples were obtained. Rectal swab samples were obtained from hospitalized patients within 36 hours of admission. Both vegetarian volunteers and hospitalized patients were interviewed about potential dietary and environmental sources of E. faecium (including consumption of meat products, touching raw meat, and contact with live food animals). Information was obtained from medical records regarding antibiotic use prior to hospital admission and presence of chronic disease. Retail poultry samples were collected four times during the study period from local grocery stores (conventional retail poultry that has typically been exposed to virginiamycin) and from health-food stores (products confirmed to be antibiotic-free poultry). Genetic markers were investigated as well (of the 10 genetic markers tested, only three were found, so testing was limited to vatE, vatD, and ermB). E. faecium isolates that were sensitive or had intermediate resistance to QD were tested for inducible resistance.
Results: E. faecium was isolated from 105 hospitalized patients and 65 vegetarians. None of the human isolates displayed full QD resistance, but a majority of isolates from both hospitalized and vegetarian subjects displayed intermediate QD resistance. Regarding genetic markers, vatE was commonly found in isolates from hospitalized subjects but not in vegetarians (vatD and ermB were rarely identified in the study population). Inducible resistance was markedly higher in isolates from hospitalized patients, and was associated with the presence of vatE. E. faecium was found in almost half of conventional retail poultry samples, and in the vast majority of antibiotic-free retail poultry products as well; however, both QD-resistance and vatE were much more common in isolates from conventional than antibiotic-free poultry products. A markedly higher level of inducible resistance to QD was found in isolates originating from conventional poultry products than from antibiotic-free chicken and turkey. Touching raw poultry and more frequent ingestion of poultry products were independently associated with the presence of vatE and inducible QD resistance in those who had not used antibiotics immediately prior to enrollment (no vegetarians had used antibiotics prior to enrollment).
Conclusion: When poultry are exposed to virginiamycin they are at increased risk of carrying E. faecium that contains streptogramin resistance genes with readily inducible resistance. This points to the potential for an increased incidence of streptogramin-resistant E. faecium infection in humans.
Study strengths: Examination of genetic markers; confirmation of antibiotic-free nature of specific poultry; use of polymerase chain reaction to confirm presence of E. faecium.
Study weaknesses: Characteristics of the hospitalized patients and vegetarian volunteers were markedly different; only 39% of eligible hospitalized patients agreed to participate; self-reporting of food exposures; temporal relationships between time of poultry ingestion and characteristics of E. faecium could not be determined due to cross-sectional nature of study.
Of note: Virginiamycin, a streptomycin antibiotic related to QD, has been used as a growth promoter in the United States for decades, increasing the weight of poultry when added to feed; a number of studies have demonstrated a relationship between exposure to virginiamycin and prevalence of QD-resistant E. faecium in food animals, and significant evidence of QD-resistant E. faecium in retail chicken and turkey in the United States already exists; streptogramin resistance is mediated in part through genes located on plasmids, meaning that resistance can be transferred; prior FDA assessments may have substantially underestimated the risk of foodborne acquisition of QD-resistant E. faecium.
We knew that: The prevalence of ampicillin- and vancomycin-resistant E. faecium in hospitalized patients has risen dramatically; QD (brand name Synercid) is one of only three drugs approved by the FDA for treatment of vancomycin-resistant E. faecium infection; Denmark banned the use of virginiamycin as a growth promoter in 1997, and the European Union followed suit shortly thereafter; studies suggest that human colonization by QD-resistant E. faecium is rare in the United States, but those studies did not evaluate genetic markers or inducible resistance; research suggests that streptogramin-resistant E. faecium occurs less often in animals raised without antibiotics; the FDA has classified streptogramin antibiotics as 'highly important' for human use, but it is uncommonly employed at present; the presence of vatE and inducible resistance in newly hospitalized patients creates a reservoir for the emergence of vancomycin-resistant, streptogramin-resistant E. faecium in the hospital.
Comments: One of the authors of this study was quoted as saying, 'We don't want to suggest to anyone that they should alter their diet based on this.' Indeed, one cannot offer a blanket recommendation that only antibiotic-free poultry should be eaten, as the largest part of the population would be unable participate. Antibiotic-free and organic products remain beyond the reach of most people, though improvements are in the offing. However, the results of the study also clearly impel us to look to government regulators to act and only allow the use of antibiotic therapy as treatment for infection, and not in widespread application to enhance weight gain of food animals. This study adds to the growing suspicion that antibiotic resistance may be spread through food. As the authors point out, this study needs to be replicated in the general population, but we need not wait for results of such a study to ask our representatives to act in the best interest of everyone, not just we lucky few who have ready access to antibiotic-free food.
What to do with this article: Make copies to hand out to your peers.
Squeeze for a Squeeze: OMT for Tension Headache
Source: Anderson RE, et al. A comparison of selected osteopathic treatment and relaxation for tension-type headaches. Headache 2006;46:1273-1280.
Goal: To compare the effects of osteopathic manipulative therapy (OMT) and progressive muscle relaxation (PMR) on people with tension-type headache (TTH).
Study design: Single-blind, randomized clinical trial performed at the Canadian College of Osteopathy.
Subjects: Twenty-nine subjects age 16 years or older with TTH (26 completed trial).
Methods: Participants were recruited through ads in the local media and flyers placed in medical offices. Subjects were randomized to perform PMR at home or to receive three OMT sessions together with home PMR exercises. Headache frequency and intensity were recorded in a headache diary (HD) for two weeks prior to study interventions. Subjects then met with the assessing practitioner and underwent a physical assessment, and also were asked to complete a health history questionnaire. Each patient received a PMR exercise audiotape and typed instructions, and was asked to practice PMR daily for 20 minutes and to record the sessions in a relaxation diary (RD). Patients in the experimental group also received one OMT session for three consecutive weeks, with treatment focused on areas previously noted in the osteopathic literature to be involved in TTH. Participants were re-assessed within two weeks following OMT, at which time HDs and RDs were collected, and repeat physical assessments were performed. Using data from the HDs, four headache outcome measures were then determined.
Results: Subjects in the experimental group experienced fewer headaches per week. Other measures showed a trend towards improvement, save for head-ache intensity, which did not reveal a significant difference between groups.
Conclusion: People with TTH who receive three OMT sessions together with home performance of PMR exercises may expect fewer headaches per week than those with TTH who only use home PMR.
Study strength: Combination of individualized OMT with generally agreed upon approaches to abnormalities found at time of physical assessment.
Study weaknesses: Potential bias introduced by setting of study (osteopathic college); small sample size; no explanation of why 17 people refused participation in the study; nearly 25% of subjects in both groups did not perform their PMR exercises.
Of note: Psychological stress and fatigue may precipitate TTH; potential subjects in this trial were not excluded if they were already using pain medication (all but one were using medication); 19 subjects had previously explored a variety of other therapies in attempts to obtain relief, including yoga therapy and chiropractic care; potential subjects were excluded if they had a history of temporomandibular joint dysfunction or traumatic headache; areas targeted during OMT were numerous and included the upper thoracic spine and ribs, clavicles, pelvis, cranium, and cervical spine; if deemed necessary, cranial osteopathic treatment was employed (utilized to release strain in the dura mater through gentle manipulation of the cranium and facial bones); the assessing practitioner was blind to patient group assignment.
We knew that: TTH is the most common type of headache, occurring in 30-78% of the population, and more often seen in women than men; contraction of head and neck muscles is felt to contribute to the pathophysiology of TTH, but this has not been proven (no accepted correlation between headache severity and EMG activity); a small number of studies, including those using PMR, have shown relaxation therapies to be of benefit in the setting of TTH; studies of TTH suggest that headache frequency is the variable most amenable to improvement; the placebo effect of any treatment for TTH is significant (estimated at up to 33%).
Comments: Most every health care practitioner frequently encounters people suffering from recurrent headaches, many of which could be rightly classified as tension headache. Potentially beneficial interventions abound and include nonspecific drug therapy, yet a significant number of people continue to experience some degree of discomfort following appropriate treatment. Relaxation therapies like PMR or OMT could be of benefit to our patients with TTH, but this paper does not help direct our recommendations. Questions left unanswered include the healing impact of a relationship with a caring osteopathic physician developed over three sessions, the contribution of human touch to perception of improvement, and an assessment of cost-effectiveness. In addition, many health care providers continue to have difficulty embracing the theory and practice of cranial osteopathy, an area of treatment that cries out for methodologically sound research. This paper piques our interest, but does not provide definitive answers.
What to do with this article: Keep a copy of the abstract on your computer.
'This Won't Hurt'—Acupuncture for Back Pain
Source: Thomas KJ, et al. Randomised controlled trial of a short course of traditional acupuncture compared with usual care for persistent non-specific low back pain. BMJ 2006; 333:623. Epub 15 Sep 2006.
Goal: To assess the effect of a short course of traditional acupuncture on long-term outcomes for people with persistent nonspecific lower back pain.
Design: Pragmatic, open, randomized controlled trial.
Subjects: People aged 18-65 years with nonspecific back pain of four to 52 weeks duration referred from 18 general practices in York, England (n = 289 referred, n = 241 randomized).
Methods: After being assessed suitable for participation in the trial, subjects were randomized to receive up to 10 individualized acupuncture sessions over three months (n = 160, all of whom remained under the care of their generalist) from one of six qualified acupuncturists at three acupuncture clinics, or usual care alone (n = 81). Allocation to an acupuncturist was based on patient convenience and appointment availability. Primary outcome measured was SF-36 bodily pain (scored 0-100, with 100 being no pain) determined at 12 and 24 months; secondary outcomes were assessed and included analgesic use, scores on the Oswestry pain disability index, the McGill present pain index, the seven remaining dimensions in the SF-36 questionnaire, patient satisfaction and acceptability, and safety. Evaluations took place at three, 12, and 24 months. A cost-effectiveness assessment at 24 months was also completed (and presented in a sister article in the same edition of the BMJ).
Results: The average number of acupuncture treatments received was 8.1 sessions. SF-36 scores increased in the acupuncture group slightly more than in the usual care group at 12 months (intervention effect of 5.6 points), and slightly more again at 24 months (significant intervention effect of 8.0 points). Changes in the Oswestry pain disability index and McGill present pain intensity measure favored acupuncture but did not reach statistical significance. At three months people receiving acupuncture were more likely to be very satisfied with treatment and their overall care; at 24 months the same group was less likely to voice concerns about back pain, to report use of analgesics for back pain, and more likely to report no pain for the prior 12 months. Functional improvement, however, was not identified. Expectations of improvement with acupuncture reinforced a positive treatment effect, but there was at best weak evidence of an interaction effect, as positive belief was associated with less therapeutic benefit than was neutral belief in the potential benefits of acupuncture. No serious side effects were reported in the acupuncture group. Authors of the sister article concluded that acupuncture added cost to treatment, but this was countered by improved long-term health-related quality of life.
Conclusion: Acupuncture has a weakly positive effect on people with persistent nonspecific lower back pain at 12 months, and a slightly stronger beneficial effect at 24 months.
Study strengths: Pragmatic design; protocol allowing for individualization of treatment respecting traditional Chinese medical tenets; unequal randomization to acupuncture group to allow for differential effects between acupuncturists to be assessed; intention-to-treat analysis.
Study weaknesses: Follow-up secured mainly by mail; 24% dropout rate at 24 months.
Of note: Approximately 16% of British adults seek care for back pain from their general practitioners; to be registered with the British Acupuncture Council one must have three years' training or equivalent (based on principles of Chinese medicine); each of the six participating acupuncturists had at least three years' clinical experience; all patients referred for acupuncture acted on the referral; acupuncturists determined the type and number of treatments required based on individual patient presentation; acupuncturists and generalists also employed massage therapy and advice on diet, exercise, and rest; all 11 participants who were unable to work as a result of lower back pain were randomized to the acupuncture group (excluding these subjects increased the estimated beneficial effect of acupuncture at 12 months); the SF-36 bodily pain dimension has been validated for use in primary care and for people with lower back pain, and assesses pain experienced during the prior four weeks; 30 of 133 subjects receiving acupuncture at least once and who provided data at three months noted a temporary worsening of low back pain that was very troubling, but 86% viewed acupuncture as relaxing, and 91% were willing to experience the treatment again; those lost to follow-up were generally younger and had lower SF-36 pain scores at three months (similar in both groups); being an open trial, neither participants nor researchers were blind to treatment assignment, but analysis of primary outcome was performed by a statistician who was blind to allocation; no evidence of reluctance on the part of generalists to refer for acupuncture was identified; acupuncture appointments were secured within two weeks of randomization; in the sister article it was noted that the initial acupuncture session accounted for 45% of total NHS costs associated with acupuncture.
We knew that: Nonspecific lower back pain, while intermittent, often is recurrent and associated with significant economic, health, and social costs; the existing evidence regarding the benefits of acupuncture for lower back pain is conflicting and inconclusive, but data do suggest short-term relief and functional improvement in those with chronic low back pain when compared with no or sham treatment (data are wanting with respect to long-term effects); the best form of management for nonspecific low back pain has yet to be agreed upon; previous authors have posited that the beneficial effects of acupuncture on pain are related to positive patient belief in the therapy; a difference of at least 5 points in the mean SF-36 bodily pain dimension score is considered representative of a worthwhile clinical intervention, while a difference of 5-9 points can be viewed as a moderate effect.
Clinical import: Considering the dual facts that nonspecific lower back pain represents a major reason for people to see their primary care physician, and that a gold standard for treating this all too common malady is yet to be agreed upon, one can readily grasp the potential importance of any positive clinical study that is also tied to perceived cost effectiveness. While the treatment effect was mild to moderate, it was lasting. Long-term assessment of acupuncture's impact is one reason this article is notable, but another is the use of individualized treatment based on principles of traditional Chinese medicine. Thus, specific needling was not tested so much as was an approach to care, something noteworthy indeed. Not only were physical symptoms alleviated to some degree by acupuncture, but emotional ones were as well, as patients seemed less worried about their situation after receiving acupuncture. The results of this work by no means lead to a 'slam dunk' recommendation for acupuncture for people with nonspecific low back pain, but few other therapeutic interventions have been shown to provide such long-lasting benefit in this circumstance, fewer still in a manner fiscally responsible.
What to do with this article: Keep a hard copy in your file cabinet.
SOURCE-Alternative Medicine Alert
