Clinical Briefs
With Comments from John La Puma, MD, FACP
T’ai Chi to Treat Hypertension
May 1999; Volume 2: 58-59
Young DR, et al. The effects of aerobic exercise and T’ai Chi on blood pressure in older people: Results of a randomized trial. J Am Geriatr Soc 1999;47:277-284.
In a suburban baltimore clinic, 62 sedentary older adults (45% black, 79% women, aged > 59 years) with systolic blood pressure 130-159 mm Hg and diastolic blood pressure < 95 mm Hg were randomized to a 12-week, moderate-intensity aerobic exercise program and a T’ai Chi program of light activity. The goal of each condition was to exercise four days per week, 30 minutes per day.
Blood pressure was measured during three screening visits and every two weeks during the intervention period. Estimated maximal oxygen uptake and measures of physical activity level were determined at baseline and at the end of the intervention period.
Mean BMI was 30.6 kg/m2; mean age was 66.7 years. Nearly half of the population met criteria for systolic hypertension. Mean (SD) baseline systolic and diastolic blood pressures were 139.9 (9.3) mm Hg and 76.0 (7.3) mm Hg, respectively. For systolic blood pressure, adjusted mean (SE) changes during the 12-week intervention period were -8.4 (1.6) mm Hg and -7.0 mm Hg in the aerobic exercise and T’ai Chi groups, respectively (each within group P < 0.001; between group P = 0.56).
For diastolic blood pressure, corresponding changes were -3.2 (1.0) mm Hg in the aerobic exercise group and -2.4 (1.0) mm Hg in the T’ai Chi group (each within group P < 0.001; between group P = 0.54). Body weight did not change in either group. Estimated maximal aerobic capacity tended to increase in aerobic exercise (P = > 0.06) but not in T’ai Chi (P = 0.24). Programs of moderate intensity aerobic exercise and light exercise may have similar effects on blood pressure in previously sedentary individuals.
COMMENT
The value of physical activity in reducing hypertension is not in question, but the intensity and type of activity is. Can T’ai Chi work as well as aerobics in older adults?
These Johns Hopkins investigators excluded patients on antihypertensives and insulin and patients with cardiovascular symptoms, and measured fitness using VO2max before randomly assigning subjects to a 1-hour group exercise conducted twice weekly, supplemented by home-based exercise.
The aerobic exercise increased progressively from 20-40 minutes by the ninth week. The goal of exercise was 40-60% of heart rate reserve (estimated maximum heart rate minus resting pulse rate).
The T’ai Chi intervention was taught in the Yang style (13 movements practiced in sequence in a slow fluid and continuous manner). According to those subjects returning exercise logs (mean 59% of the aerobic group; 45% of the T’ai Chi group), 96% practiced T’ai Chi four or more sessions per week but only 58% practiced aerobic activity that often.
Udani writes, "The three basic principles of T’ai Chi are: 1) the body should be extended and relaxed; 2) the mind must be alert but calm; and 3) all body movements require a well-coordinated sequencing of segments. This stance is combined with deep diaphragmatic breathing, which is common among the martial arts and many forms of meditation." (See Alternative Medicine Alert, October 1998, p. 116.)
To their credit, these investigators did not try to prescribe exercise times in Workout World settings, and recognized that most adults prefer light and moderate activity to vigorous exercise (for better or worse). Similarly, T’ai Chi does not require a specific set of clothes, special shoes, a particular setting or new equipment—all of which can be barriers to people who are not used to exercising.
The problems in this study are those the authors recognize: no no-exercise group; a widely variable adherence to prescribed regimens (average 65%); reliance on a seven-day physical activity recall (often inaccurate); and likely selection bias. Adverse events are not reported, but T’ai Chi is safely practiced by literally tens of millions of Chinese daily. Musculoskeletal injuries from aerobic exercise, conversely, are well-documented.
Recommendation
Much better studies need to be done before we can say with surety that T’ai Chi lowers blood pressure. But this promising pilot deserves a longer trial with better controls and adherence.
Steroids in Chinese Herbal Creams
May 1999; Volume 2: 59-60
Keane FM, et al. Analysis of Chinese herbal creams prescribed for dermatological conditions. BMJ 1999;318:563-564.
To determine whether chinese herbal creams used for the treatment of dermatalogical conditions contain steroids, 11 herbal creams obtained from patients attending general and pediatric dermatology outpatient clinics were analyzed with high resolution gas chromatography and mass spectrometry. Eight creams contained dexamethasone at a mean concentration of 456 mcg/g (range 64-1500 mcg/g). All were applied to sensitive skin areas such as face and flexures, sometimes several times daily. Greater regulations should be imposed on Chinese herbalists to prevent illegal and inappropriate prescribing of potent steroids.
Comment
People gravitate to Chinese herbalists for a cure, just like they come to primary care physicians for an itchy, scratchy rash that just won’t go away. This report, from the Departments of Dermatology and Clinical Biochemistry at King’s College Hospital in London, arose from the clinical observation that patients with eczema often reported improvement with Chinese herbal creams. These same patients returned to the National Health Service clinic after seeing the herbalist "when they could no longer afford the herbs (the cost was up to 35 pounds per week)"—approximately $45.
Sadly, seven of these patients were children, one only four months old and the one who received the greatest amount of steroid. The indications for prescription were eczema in seven cases, scaly scalp in two cases and eczema herpeticum in one case. All the bottles prescribed for eczema contained dexamethasone. Of the two bottles that were labeled (in Chinese), none contained dexamethasone; 456 mcg/g of dexamethasone is roughly equivalent to 0.05% betamethasone valerate.
The authors could not discover the original source of the creams, but speculate that individual mixing occurred at different shops, and that "personalized, unlabeled, unstandardized preparations" were given to patients. They note the "inadvertent use of topical steroid can cause severe exacerbation of eczema herpeticum" and denounce the use of steroids in "concentrations inappropriate for use on the face or in children." Like in the U.S., the source and quality of ingredients in the U.K. is not standardized, and hepatotoxicity has been reported from oral preparations for eczema.
Eczema (atopic dermatitis) usually spontaneously subsides by the time infants become toddlers. Though steroids suppress the itching, so do hydrating emollients, and the use of even topical steroids remains controversial. Schiedermayer writes, "Clinical trials are notoriously difficult to perform, because of the inherent variability of the clinical state, the subjective nature of the assessment, and a large placebo response." (See Alternative Medicine Alert, January 1999, p.9.)
Recommendation
Patients who use individually prepared Chinese herbal creams for skin disorders have a good chance of receiving steroids—in this case, high-powered dexamethasone. Until such creams are manufactured, labeled, and regulated like the powerful medications they are, no parent should apply these creams to the face of a child, and no physician should recommend them.
PENS for Relief of Low Back Pain
May 1999; Volume 2: 60
Ghoname EA, et al. Percutaneous electrical nerve stimulation for low back pain: A randomized crossover study. JAMA 1999;281: 818-823.
Low back pain (lbp) contributes to considerable disability and lost wages in the United States. Commonly used opioid and nonopioid analgesic drugs produce adverse effects and are of limited long-term benefit in the management of this patient population.
The effectiveness of a novel nonpharmacologic pain therapy, percutaneous electrical nerve stimulation (PENS), was compared to transcutaneous electrical nerve stimulation (TENS) and flexion-extension exercise therapies with long-term LBP. We used a randomized, single-blinded sham-controlled crossover design from 3/97-12/97 in an ambulatory pain management center at a university medical center.
Twenty-nine men and 31 women with LBP from degenerative disk disease of at least three months duration were randomized to four administered therapeutic modalities (sham-PENS, PENS, TENS, and exercise therapies) for 30 minutes three times a week for three weeks, with one week off between therapies. PENS was significantly more effective in decreasing visual analog scale (VAS) pain scores after each treatment than sham-PENS, TENS, and exercise therapies.
After treatment, mean +/- SD VAS scores for pain were 3.4/1.4 for sham PENS, 5.5/1.9 for PENS, 5.6/1.9 for TENS, and 6.4/1.9 for exercise therapy. The average +/- SD daily oral intake of nonopioid analgesics (2.6/1.4 pills daily) was decreased to 1.3/1.0 daily with PENS (P < 0.008) compared with 2.5/1.1, 2.2/1.0, and 2.6/1.2 daily with sham-PENS, TENS and exercise, respectively. Compared with the other three modalities, 91% of the patients reported that PENS was the most effective in decreasing their LBP. The PENS therapy was also significantly more effective in improving physical activity, quality of sleep, and sense of well-being (P < 0.05 for each). The SF-36 survey confirmed that PENS improved post-treatment function more than sham-PENS, TENS, and exercise.
In this sham-controlled study, PENS was more effective than TENS or exercise therapy in providing short-term pain relief and improved physical function in patients with long-term LBP.
Comment
This well-designed Dallas study has some flaws: the exercise prescribed was a simple spine flexion-extension repeated 30 times in 30 minutes; follow-up was limited to 72 hours; patients using opioids for LBP were excluded; how many patients had radiculopathy, if any, is not stated; and a double-blind design was not possible. Overall, its results are impressive in a notoriously difficult-to-treat population, albeit over the short-term.
PENS produced an acute analgesic effect immediately after each treatment, though it took three to four treatments to change their VAS scores for pain, activity, and sleep, and to decrease the consumption of oral analgesics, significantly beating TENS treatment alone.
PENS combines TENS with electroacupuncture to stimulate peripheral sensory nerves at the dermatomal levels corresponding to the local pathology. Ten 32 gauge stainless steel probes were connected to five bipolar leads connected to a small, non-FDA-approved electrical generator. The probes were placed deliberately into soft tissue or muscle from T12 to S2 and were stimulated at a frequency of 4 Hz for 0.5 milliseconds. In contrast, TENS used 4 one-inch cutaneous electrode pads, stimulated at 4 Hz for 0.1 milliseconds.
A recent randomized controlled trial with two-year follow-up comparison of chiropractic, physiotherapy, and an educational booklet for LBP showed approximately equivalent effectiveness (N Engl J Med 1998;339:1021-1029) with highest patient satisfaction for chiropractic and least cost for the educational booklet.
A new field of medicine—perhaps called "musculoskeletal medicine"—is emerging from between the cracks of rheumatology, physiatry, orthopedics, sports medicine, and anesthesiology. Physicians seriously interested in these patients approach their diseases from a multimodal rehabilitative perspective rather than a curative one. The main barriers to their success will be the time required to establish a therapeutic alliance.
Recommendation
As part of a multimodal approach to back pain, PENS warrants serious consideration in longer trials to test whether it can improve short- or long-term pain or improve function in a lasting fashion.
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