Clinical Health Updates

Probiotics effective in preventing acute diarrhea, but not traveler’s diarrhea

Clinical Question:
Are probiotics effective in the prevention of acute diarrhea?

Bottom Line:
Probiotics reduce the risk of antibiotic-associated diarrhea and other types of acute diarrhea, but not the risk of traveler’s diarrhea, in both children and adults. The protective effect does not vary among different probiotic strains nor by mode of delivery.

Reference:
Sazawal S, Hiremath G, Dhingra U, Malik P, Deb S, Black RE. Efficacy of probiotics in prevention of acute diarrhea: A meta-analysis of masked, randomized, placebo-controlled trials. Lancet Infect Dis 2006;6:374-382.

Study Design:
Meta-analysis (randomized controlled trials)

Synopsis:
The author did a meta-analysis of the available data from 34 masked, randomised, placebo-controlled trials. Only one trial was community based and carried out in a developing country. Most of the remaining 33 studies were carried out in a developed country in a health-care setting. Evaluating the evidence by types of acute diarrhoea suggests that probiotics significantly reduced antibiotic-associated diarrhoea by 52% (95% CI 35-65%), reduced the risk of travellers’ diarrhoea by 8% (-6 to 21%), and that of acute diarrhoea of diverse causes by 34% (8-53%). Probiotics reduced the associated risk of acute diarrhoea among children by 57% (35-71%), and by 26% (7-49%) among adults. The protective effect did not vary significantly among the probiotic strains Saccharomyces boulardii, Lactobacillus rhamnosus GG, Lactobacillus acidophilus, Lactobacillus bulgaricus, and other strains used alone or in combinations of two or more strains. Although there is some suggestion that probiotics may be efficacious in preventing acute diarrhoea, there is a lack of data from community-based trials and from developing countries evaluating the effect on acute diarrhoea unrelated to antibiotic usage. The effect on acute diarrhoea is dependent on the age of the host and genera of strain used.

Transcedental meditation effective on metabolic syndrome and CHD

Clinical Question:
Does transcedental meditation effective on components of metabolic syndrome (blood pressure, insulin resistance, etc) and coronary heart disease?

Bottom Line:
Use of TM for 16 weeks in CHD patients improved blood pressure and insulin resistance components of the metabolic syndrome as well as cardiac autonomic nervous system tone compared with a control group receiving health education. These results suggest that TM may modulate the physiological response to stress and improve CHD risk factors, which may be a novel therapeutic target for the treatment of CHD.

Reference:
Effects of a randomized controlled trial of transcendental meditation on components of the metabolic syndrome in subjects with coronary heart disease.
Paul-Labrador M, Polk D, Dwyer JH, Velasquez I, Nidich S, Rainforth M, Schneider R, Merz CN.Arch Intern Med. 2006 Jun 12;166(11):1218-24

Study Design:
Randomized Controlled Trial

Synopsis:
The metabolic syndrome is thought to be a contributor to coronary heart disease (CHD), and components of the syndrome have been identified as possible therapeutic targets. Previous data implicate neurohumoral activation related to psychosocial stress as a contributor to the metabolic syndrome. The author evaluate the efficacy of transcendental meditation (TM) on components of the metabolic syndrome and CHD. They conducted a randomized, placebo-controlled clinical trial of 16 weeks of TM or active control treatment (health education), matched for frequency and time, at an academic medical center in a total of 103 subjects with stable CHD. Main outcome measures included blood pressure, lipoprotein profile, and insulin resistance determined by homeostasis model assessment (calculated as follows: [(fasting plasma glucose level [in milligrams per deciliter] x fasting plasma insulin level [in microunits per milliliter]) x 0.0552]/22.5); endothelial function measured by brachial artery reactivity testing; and cardiac autonomic system activity measured by heart rate variability. The TM group had beneficial changes (measured as mean +/- SD) in adjusted systolic blood pressure (-3.4 +/- 2.0 vs 2.8 +/- 2.1 mm Hg; P = .04), insulin resistance (-0.75 +/- 2.04 vs 0.52 +/- 2.84; P = .01), and heart rate variability (0.10 +/- 0.17 vs -0.50 +/- 0.17 high-frequency power; P = .07) compared with the health education group, respectively. There was no effect of brachial artery reactivity testing.

Coffee does not increase risk of developing coronary artery disease

Clinical Question:
Does coffee consumption increase the risk of heart disease?

Bottom Line:
There is no evidence that coffee consumption increases the likelihood that someone will develop heart disease. (LOE = 2b)

Reference:
Lopez-Garcia E, van Dam RM, Willett WC, et al. Coffee consumption and coronary heart disease in men and women: a prospective cohort study. Circulation 2006;113:2045-2053.

Study Design:
Cohort (prospective)

Synopsis:
The author examined the association between long-term habitual coffee consumption and risk of coronary heart disease (CHD). They performed a prospective cohort study with 44,005 men and 84,488 women without history of cardiovascular disease or cancer. Coffee consumption was first assessed in 1986 for men and in 1980 for women and then repeatedly every 2 to 4 years; the follow-up continued through 2000. We documented 2173 incident cases of coronary heart disease (1449 nonfatal myocardial infarctions and 724 fatal cases of CHD) among men and 2254 cases (1561 nonfatal myocardial infarctions and 693 fatal cases of CHD) among women. Among men, after adjustment for age, smoking, and other CHD risk factors, the relative risks (RRs) of CHD across categories of cumulative coffee consumption (<1> or =6 cups/d) were 1.0, 1.04 (95% confidence interval 0.91 to 1.17), 1.02 (0.91 to 1.15), 0.97 (0.86 to 1.11), 1.07 (0.88 to 1.31), and 0.72 (0.49 to 1.07; P for trend=0.41); among women, the RRs were 1.0, 0.97 (0.83 to 1.14), 1.02 (0.90 to 1.17), 0.84 (0.74 to 0.97), 0.99 (0.83 to 1.17), and 0.87 (0.68 to 1.11; P for trend=0.08). Stratification by smoking status, alcohol consumption, history of type 2 diabetes mellitus, and body mass index gave similar results. Similarly, we found no effect when the most recent coffee consumption was examined. RRs for quintiles of caffeine intake varied from 0.97 (0.84 to 1.10) in the second quintile to 0.97 (0.84 to 1.11) in the highest quintile (P for trend=0.82) in men and from 1.02 (0.90 to 1.16) to 0.97 (0.85 to 1.11; P for trend=0.37) in women.

Single dose azithromycin (Zithromax) effective for cholera

Clinical Question:
Is a single dose of azithromycin (Zithromax) effective for the treatment of severe cholera?

Bottom Line:
While tetracycline (1 g to 2 g) or doxycycline (300 mg) in a single dose remains an effective and inexpensive treatment for cholera in older children and adults, azithromycin in a single 1-g dose is an effective (although somewhat more expensive) alternative. It has been shown in previous studies to be a good choice for younger children who cannot take tetracycline or doxycycline.The lack of efficacy of ciprofloxacin may result from its diminished activity against V. cholerae O1 strains currently circulating in Bangladesh

Reference:
Saha D, Karim MM, Khan WA, Ahmed S, Salam MA, Bennish ML. Single-dose azithromycin for the treatment of cholera in adults. N Engl J Med 2006;354:2452-2462.

Study Design:
Randomized controlled trial (double-blinded)

Synopsis:
Single-dose azithromycin is effective in the treatment of severe cholera in children, but its effectiveness in adults has not been evaluated. The author conducted a double-blind, randomized trial comparing the equivalence of azithromycin and ciprofloxacin (each given in a single 1-g dose of two 500-mg tablets) among 195 men with severe cholera caused by Vibrio cholerae O1 or O139. Patients were hospitalized for five days. A stool culture was performed daily. Primary outcome measures were clinical success (the cessation of watery stools within 48 hours after drug administration) and bacteriologic success (the inability to isolate V. cholerae after 48 hours). Therapy was clinically successful in 71 of 97 patients receiving azithromycin (73 percent) and in 26 of 98 patients receiving ciprofloxacin (27 percent) (P<0.001) and bacteriologically successful in 76 of 97 patients receiving azithromycin (78 percent) and in 10 of 98 patients receiving ciprofloxacin (10 percent) (P<0.001). Patients who were treated with azithromycin had a shorter duration of diarrhea than did patients treated with ciprofloxacin (median, 30 vs. 78 hours); a lower frequency of vomiting (43 percent vs. 67 percent); fewer stools (median, 36 vs. 52); and a lower stool volume (median, 114 vs. 322 ml per kilogram of body weight). The median minimal inhibitory concentration of ciprofloxacin for the 177 isolates of V. cholerae O1 was 0.25 mug per milliliter, which was 11 to 83 times as high as that in previous studies at this site.

Multidetector CT accurate for pulmonary embolism, but requires clinical context

Clinical Question:
How accurate is multidetector computed tomography for pulmonary embolism?

Bottom Line:
In patients with suspected pulmonary embolism, multidetector CTA-CTV has a higher diagnostic sensitivity than does CTA alone, with similar specificity. The predictive value of either CTA or CTA-CTV is high with a concordant clinical assessment, but additional testing is necessary when the clinical probability is inconsistent with the imaging results.

Reference:
Stein PD, Fowler SE, Goodman LR, et al, for the PIOPED II Investigators. Multidetector computed tomography for acute pulmonary embolism. N Engl J Med 2006;354:2317-2327.

Study Design:
Diagnostic test evaluation

Synopsis:
CT technology continues to evolve, now moving from single slice CT to 4-slice or 16-slice multidetector scans. In this study, 824 patients with suspected PE underwent a standard clinical evaluation using the Wells clinical decision rule, CTA, CTA-CTV, ventilation perfusion (VQ) scanning, venous compression ultrasound of the legs, and pulmonary digital subtraction angiography (DSA), if necessary. Patients were drawn from a group of 7284 patients with suspected PE, but large numbers were excluded because they couldn’t complete testing within 36 hours, had abnormal renal function, declined to participate, were using anticoagulants, or were otherwise unable to complete the protocol. The mean age of participants was 51 years, 65% were white, and 62% were women. Defined by the composite reference standard (high probability VQ scan, abnormal DSA result, or abnormal venous ultrasound and nondiagnostic VQ scan), 192 (23%) had a PE. Among those who’d had PE ruled out using this reference standard, only 2 had a likely PE during the 6-month follow-up. Also, 51 had CTA that was of insufficient quality and 87 had a CTA-CTV of poor quality, and they were excluded from the analysis. The CTA was 83% sensitive and 96% specific (positive likelihood ratio [LR+] = 19.6; negative likelihood ratio [LR-] = 0.18) and the CTA-CTV was 90% sensitive and 95% specific (LR+ = 16.5; LR- = 0.11).

It’s important to note that the predictive value of the tests depended on the clinical assessment. The Wells rule was used to stratify patients as high, intermediate, or low risk. The positive predictive value of CTA and CTA-CTV was 96%, but the negative predictive value was only 60% to 82% for those tests. However, for patients with a low clinical probability, the positive predictive value was only 57% to 58%, while the negative predictive value was a robust 96% to 97%. Values for positive and negative predictive value in intermedate probability patients were between 89% and 92%.

Metronidazole gel prevents recurrences of Bacterial Vaginosis

Clinical Question:
Does suppressive therapy with metronidazole intravaginal gel prevent recurrences of bacterial vaginosis?

Bottom Line:
Suppressive therapy with twice-weekly metronidazole gel achieves a significant reduction in the recurrence rate of bacterial vaginosis; however, secondary vaginal candidiasis is common.

Reference:
Sobel JD, Ferris D, Schwebke J, et al. Suppressive antibacterial therapy with 0.75% metronidazole vaginal gel to prevent recurrent bacterial vaginosis. Am J Obstet Gynecol 2006;194:1283-1289.

Study Design:
Randomized controlled trial (double-blinded)

Synopsis:
A total of 112 women with a history of recurrent bacterial vaginosis who’d responded to a course of treatment with 0.75% metronidazole vaginal gel were randomized to receive additional 5 g doses twice weekly or placebo as suppressive therapy for 28 weeks. They were then followed up for an additional 28 weeks. Women were evaluated every 4 weeks using Amsel criteria and Nugent score. Fifteen percent of women did not return for any follow-up visit. The probability of remaining cured was 70% for the treated group and 39% for the control group during active treatment, which declined to 34% and 18% during the follow-up period. The mean number of recurrences during the study year was 1.6 in the treated group and 3.2 in the control group. There were 2 adverse effects that occurred more frequently in the treated group: vaginal candidiasis (43% vs 21%; P = .02; number needed to treat to harm [NNTH] = 5) and complaints of head, low back, abdominal, or leg pain (28% vs 9%; P = .023; NNTH = 5).

Role of Olmesartan on migraine

Clinical Question:
Does olmesartan (OLMETEC) effective as prophylactic agent on preventing migraine attack?

Bottom Line:
The favorable results and low rate of adverse effects, in this open migraine prevention study in patients with hypertension or prehypertension, are similar to results of the randomized, double-blind, placebo-controlled, crossover study in patients taking candesartan. Olmesartan shows a potential as an effective and well-tolerated migraine prophylactic agent for patients with comorbid hypertension and prehypertension.

Reference:
Prevention of migraine with olmesartan in patients with hypertension/prehypertension.Charles JA, Jotkowitz S, Byrd LH.Headache. 2006 Mar;46(3):503-7.

Study Design:
Randomized Controlled Trial

Synopsis:
To explore the effects of olmesartan on frequency and severity of migraine attacks in patients with comorbid hypertension and prehypertension. A randomized, double-blind, placebo-controlled, crossover study with a total of 60 patients has demonstrated the efficacy and safety of the angiotensin II receptor blocker candesartan in migraine prophylaxis. The author study the potential efficacy and tolerability of olmesartan in preventing migraine in patients with hypertension and prehypertension. Twenty-four adults, aged 27 through 76, with either hypertension or prehypertension, were included in this open-label study. Participants suffered from migraines (diagnosed according to International Headache Society classifications) for at least 3 months. Patients were treated with 10 to 40 mg of olmesartan per various observational periods of at least 3 months. Frequency and severity were recorded by office visits or by telephonic interview. Patients reported an 82.5% average reduction in the frequency of migraine attacks. Patients also experienced a 45% average reduction in the severity of migraine attacks measured on a numeric pain scale of 1 to 10. The only undesired effect was dizziness or presyncope. No serious adverse events occurred and no adverse event caused a premature termination. Two patients had no reduction in headache frequency, intensity, and blood pressure.

Condom versus indwelling urinary catheters

Clinical Question:
Which is better in terms of risk of infection and patient satisfaction, condom catheter or indwelling catheter?

Bottom Line:
The use of condom catheters is less likely to lead to bacteriuria, symptomatic UTI, or death than the use of indwelling catheters. This protection is especially apparent in men without dementia.

Reference:
Condom versus indwelling urinary catheters: a randomized trial.Saint S, Kaufman SR, Rogers MA, Baker PD, Ossenkop K, Lipsky BA.J Am Geriatr Soc. 2006 Jul;54(7):1055-61.

Study Design:
A prospective, randomized, unblinded, controlled trial

Synopsis:
To compare condom and indwelling urinary catheters in terms of infection risk and patient satisfaction. A prospective, randomized, unblinded, controlled trial. An academically affiliated Veterans Affairs Medical Center. Hospitalized men aged 40 and older who required a urinary collection device. The incidence of adverse outcomes (bacteriuria, symptomatic urinary tract infection (UTI), or death) and patient device-related satisfaction as determined according to a questionnaire. Dementia status was recorded to assess effect modification by the presence of dementia. Seventy-five subjects were randomized: 41 receiving an indwelling catheter and 34 a condom catheter. The incidence of an adverse outcome was 131/1,000 patient-days with an indwelling catheter and 70/1,000 patient-days with a condom catheter (P=.07). The median time to an adverse event was 7 days in the indwelling group and 11 days in the condom group. After adjusting for other risk factors, it was found that condom catheter use reduced adverse outcomes (P=.04). Patients without dementia who had an indwelling catheter were approximately five times as likely to develop bacteriuria or symptomatic UTI or to die (hazard ratio=4.84, 95% confidence interval=1.46-16.02) as those with a condom catheter (P=.01). Patients reported that condom catheters were more comfortable (P=.02) and less painful (P=.02) than indwelling catheters.

Cereal fiber intake reduced risk of type 2 diabetes mellitus

Clinical Question:
Does increased insoluble dietary fiber intake improves whole-body insulin sensitivity in overweight and obese women?

Bottom Line:
Increased insoluble dietary fiber intake for 3 days significantly improved whole-body insulin sensitivity. These data suggest a potential mechanism linking cereal fiber intake and reduced risk of type 2 diabetes.

Reference:
Cereal fiber improves whole-body insulin sensitivity in overweight and obese women.Weickert MO, Mohlig M, Schofl C, Arafat AM, Otto B, Viehoff H, Koebnick C, Kohl A, Spranger J, Pfeiffer AF. Diabetes Care. 2006 Apr;29(4):775-80.

Study Design:
Randomized, controlled, single-blind, cross-over study

Synopsis:
Cereal fiber intake is linked to reduced risk of type 2 diabetes in epidemiological observations. The pathogenic background of this phenomenon is unknown. Based on recent findings, the author hypothesized that intake of purified insoluble oat fiber may improve whole-body insulin sensitivity. A randomized, controlled, single-blind, cross-over study was performed, and 17 overweight or obese subjects with normal glucose metabolism were analyzed. After consumption of nine macronutrient-matched portions of fiber-enriched bread (white bread enriched with 31.2 g insoluble fiber/day) or control (white bread) over a time period of 72 h, whole-body insulin sensitivity was assessed by euglycemic-hyperinsulinemic clamp. Energy intake was individually adjusted by providing standardized liquid meals. Hydrogen breath tests were performed to control for dietary adherence. When analyzing the entire cohort, whole-body glucose disposal was improved after fiber consumption (M value 6.56 +/- 0.32 vs. 6.07 +/- 0.27 mg . min(-1) . kg(-1); P = 0.043). Thirteen subjects had increased hydrogen breath test concentrations after fiber consumption, indicating probable dietary adherence. Restricting analysis to these subjects, improvements in M value (6.85 +/- 0.34 vs. 6.06 +/- 0.32 mg . min(-1) . kg(-1); P = 0.003) and insulin sensitivity, expressed as M/I ratio (M value divided by mean serum insulin at steady state: 3.73 +/- 0.23 vs. 3.21 +/- 0.27; P = 0.02), after fiber consumption were more pronounced. Plasma lipids, serum magnesium, ghrelin, and adiponectin concentrations, as well as substrate utilization and body weight, were not significantly changed by fiber intake (P > 0.15).

Progestational agents reduce preterm birth

Clinical Question:
Do progestational agents started in the second trimester of pregnancy prevent preterm birth for women at increased risk?

Bottom Line:
Progestational agents, initiated in the second trimester of pregnancy, may reduce the risk of delivery less than 37 weeks’ gestation, among women at increased risk of spontaneous preterm birth, but the effect on neonatal outcome is uncertain. Larger randomized controlled trials are required to determine whether this treatment reduces perinatal mortality or serious neonatal morbidity.

Reference:
Mackenzie R, Walker M, Armson A, Hannah ME. Progesterone for the prevention of preterm birth among women at increased risk: A systematic review and meta-analysis of randomized controlled trials. Am J Obstet Gynecol 2006;194:1234-1242.

Study Design:
Meta-analysis (randomized controlled trials)

Synopsis:
This meta-analysis included 3 randomized placebo-controlled controlled trials with 648 women in which progestational agents were started in the second trimester to prevent preterm birth. Studies that did not present data according to intention to treat or with more than 20% loss to follow-up were excluded. Two studies used weekly intramuscular injections with 250 mg 17alpha-hydroxyprogesterone caproate. The other study used natural progesterone administered in 100 mg intravaginal suppositories daily. The risk of preterm delivery was significantly lower with treatment (relative risk = 0.57; 95% CI, 0.36-0.90; number needed to treat= 6). The risk of a less than 2500 g birth weight was similarly reduced. However, the meta-analysis failed to identify any differences in perinatal mortality or serious morbidity.