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PubMed2000

A comparison of the efficacy and tolerance of pancrelipase and placebo in the treatment of steatorrhea in cystic fibrosis patients with clinical exocrine pancreatic insufficiency.

OBJECTIVE: The safety and efficacy of Minimicrospheres, which are enteric-coated, delayed-release pancrelipase capsules, on fat absorption in pediatric/adolescent and adult cystic fibrosis (CF) patients was assessed. Exocrine pancreatic insufficiency, common in CF patients, causes steatorrhea due to insufficient release of pancreatic enzymes. METHODS: In the open-label phase, 97 CF patients with pancreatic insufficiency and steatorrhea were stabilized on a high-fat diet and administered pancrelipase. Seventy-four patients with >80% coefficient of fat absorption received placebo or pancrelipase in the double-blind phase. Fat intake and excretion, stool frequency and consistency, and clinical global improvement were recorded. RESULTS: Average daily fat intake was comparable between treatment groups within each age group (adults vs pediatric/adolescent), but placebo patients had a significant (p < 0.001) mean decrease in coefficient of fat absorption (adult, 36.9 percentage points; pediatric/adolescent, 34.9 percentage points) from open-label to double-blind treatment compared to pancrelipase patients (adult, 2 percentage points; pediatric/adolescent, 3.25 percentage points); this difference was caused by a greater (p < or = 0.001) increase in mean fecal fat excretion (grams per day) in the placebo groups compared to pancrelipase groups (adult: 61.9 vs 2.3; pediatric/adolescent: 45.4 vs 4.1). Change in mean stool frequency from open-label to double-blind phases was significantly different (p < or = 0.002) between treatment groups, with increases in placebo groups and no difference (adult) or decrease (pediatric/adolescent) in pancrelipase groups. Pancrelipase patients' stool consistency remained about the same from open-label to double-blind. Placebo patients' stool consistency decreased (became softer) from open-label pancrelipase to double-blind placebo. Clinical global improvement data showed that > or =83% of pancrelipase patients improved or remained unchanged. CONCLUSIONS: Enteric-coated, delayed-release (Minimicrospheres) pancrelipase capsules are an effective treatment for steatorrhea associated with pancreatic insufficiency in patients with cystic fibrosis.

Adult↗
PubMed1978

A controlled long-term study of flunitrazepam, nitrazepam and placebo, with special regard to withdrawal effects.

The hypnotic effect of flunitrazepam (Ro 5-4200), nitrazepam and a placebo was studied in 117 outpatients using hypnotics for at least 3 months prior to the study. They obtained various neurotropic drugs and this and other treatments were unchanged throughout the trial period of 13 weeks. This consisted of 3 weeks on the previously used hypnotic, 3 weeks on a test drug (during the first of these a doubling of the dose was permitted if the initial dose of 1 mg flunitrazepam, 5 mg nitrazepam or one tablet of placebo was not satisfactory) and 4 weeks' observation after a request to stop medication with the test drug. The effects were evaluated every week by self-ratings. Also noted were: the frequency of dose increase after 1 week of the test period, number of drop-outs in the test period, and failure in the attempt to stop taking the test drug. A "psychological concentration test" was done, as was a follow-up interview. The self-ratings had a good reliability and showed that more patients experienced shorter sleep induction, longer sleep time, better sleep quality and a subjective feeling of having had a better rest with flunitrazepam than with either nitrazepam or placebo. There were no differences between the nitrazepam and the placebo groups. Tiredness was the most common side effect and appeared in the same frequency in all groups. The number of patients who increased the dose after 1 week's medication, as well as the number of drop-outs, was significantly higher in the nitrazepam and placebo groups than in the flunitrazepam group. There was no difference in the ability to discontinue the medication between the test groups or between groups having previously used different hypnotics. The "psychological concentration test" did not reveal any differences between groups. It was concluded that withdrawal of a hypnotic in chronic users was not facilitated by the use of a placebo. This was interpreted as due to a strong psychological dependence upon the hypnotics and their lack of pharmacological effects during long-term treatment.

Adult↗
PubMed1998

6-month use of 0.2% delmopinol hydrochloride in comparison with 0.2% chlorhexidine digluconate and placebo. (I). Effect on plaque formation and gingivitis.

A double-blind, randomised, 6-month clinical trial with parallel group design in 149 patients with gingivitis was conducted to study the efficacy and safety of delmopinol hydrochloride 2 mg/ml (0.2% w/v, Decapinol Mouthwash) used for partly supervised mouthrinsing in comparison with chlorhexidine digluconate 2 mg/ml (0.2% w/v, Hibitane Dental, ICI Pharmaceuticals, UK) and placebo as an addition to normal oral hygiene. Assessments of efficacy were performed using the plaque index and bleeding on probing (BOP). Delmopinol showed 22% lower plaque index scores than placebo after 3 months (p<0.01) and 13% lower scores after 6 months. The corresponding figures for chlorhexidine were 38% (p<0.001) and 38% (p<0.001) after 3 and 6 months, respectively. Bleeding on probing was reduced for delmopinol in comparison with placebo by 11% after 3 months and by 18% (p<0.05) after 6 months. For chlorhexidine the corresponding figures were 18% (p<0.01) and 22% (p<0.01) after 3 and 6 months, respectively. While chlorhexidine showed greater plaque reduction than delmopinol (p<0.01 at 6 months), no statistically significant difference was reached between these two solutions regarding BOP. Both active solutions showed an increased amount of dental calculus in comparison with placebo. A transient anaesthetic sensation in the oral mucosa and taste affection were commonly reported adverse events in both the delmopinol and the chlorhexidine groups. The number of patients withdrawn from treatment due to adverse events or lack of cooperation was 7 in the chlorhexidine group, 4 in the placebo group and 1 in the delmopinol group. The results showed that rinsing with either 0.2% delmopinol hydrochloride or 0.2% chlorhexidine digluconate twice daily for 60 secs for 6 months results in less plaque formation and gingivitis than rinsing with placebo. Mouthrinsing with the 0.2% delmopinol hydrochloride solution was well accepted in this study.

Adult↗
PubMed1985

Diltiazem and propranolol, alone and in combination, on exercise performance and left ventricular function in patients with stable effort angina: a double-blind, randomized, and placebo-controlled study.

Diltiazem and propranolol alone and in combination as antianginal agents were compared with placebo in 12 patients with stable exertional angina at Stanford University Medical Center. The patients performed symptom-limited, multi-stage upright bicycle ergometric exercise while undergoing radionuclide angiographic studies every two weeks while being treated with 90 mg of diltiazem four times daily, 60 mg of propranolol four times daily, a combination of 90 mg of diltiazem and 60 mg of propranolol four times daily, and placebo. Diltiazem, propranolol and a combination all significantly increased exercise duration compared to placebo (526 +/- 149, 525 +/- 115, and 549 +/- 129 vs 430 +/- 132 sec.). Although rate pressure product and heart rate decreased with diltiazem therapy at submaximal workloads, these values were unchanged at peak exercise in contrast to propranolol or the combination of propranolol or diltiazem. Diltiazem decreased the sub-maximal and maximal degree of exercise-induced ST segment depression by over 50% compared to placebo (P less than 0.01 vs placebo). Diltiazem resulted in a higher exercise left ventricular ejection fraction compared to placebo, propranolol or the combination of diltiazem or propranolol (all less than P less than 0.05). Sinus bradycardia or orthostatic hypertension occurred in four patients on the high-dose combination therapy and required dose reduction. We concluded that high-dose diltiazem, appeared to be even more effective than moderate-dose propranolol or the combination of diltiazem and propranolol in improving exercise tolerance, electrocardiographic evidence of myocardial ischaemia and left ventricular function in patients with stable effort angina due to occlusive coronary artery disease.

Aged↗
PubMed2004

Earliest time to onset of action leading to successful intercourse with vardenafil determined in an at-home setting: a randomized, double-blind, placebo-controlled trial.

INTRODUCTION: Vardenafil, a potent and selective oral PDE5 inhibitor, is efficacious and generally well-tolerated in men with erectile dysfunction (ED). Of considerable interest to patients and physicians is an understanding of the time required after dosing to attain penile erection sufficient for successful sexual intercourse. AIM: To determine the earliest time to onset of action of vardenafil 10 and 20 mg leading to successful intercourse compared to placebo in men with ED. METHODS: A prospective, randomized, double-blind, parallel-group, at-home study of 732 men with ED (mean age 55.5 years) was conducted at 64 sites in North America and Europe. Following a 4-week run-in period, patients were randomized to either vardenafil 10 (N = 237) or 20 mg (N = 248) or placebo (N = 247) to be taken on demand over 4 weeks. Using a stopwatch, patients recorded the elapsed time from dosing to attainment of an erection perceived to be adequate for penetration that led to intercourse completion. Earliest time of onset was defined as the fastest time among the first four doses for each patient. Time points from 25 to 5 minutes were tested for significance (alpha = 0.025) using a backward stepping procedure. RESULTS: Mean baseline erectile function domain score (13.4) indicated moderate ED. Within 25 minutes after dosing, 50%/53% of men on vardenafil 10/20 mg had at least one erection in the first four doses perceived to be sufficient for penetration with subsequent intercourse completion compared to 26% on placebo (P < 0.0001). A statistically superior response to vardenafil vs. placebo was observed in these responders at all times >or= 10 and >or= 11 minutes (P < 0.025) in the 10 and 20 mg groups, respectively. In a retrospective analysis using time intervals of <or= 15, <or= 20, <or= 25 and <or= 30 minutes between dosing and erection adequate for penetration, 75-77% of these intercourse attempts were successful (SEP3 positive) by patients receiving vardenafil 10/20 mg, compared to 45-47% of attempts by those who received placebo. Vardenafil 10/20 mg was generally well-tolerated with headache (7%/12% vs. 1%) and flushing (6%/9% vs. < 1%) reported more frequently than with placebo. No patient discontinued vardenafil therapy due to adverse events. CONCLUSION: In this large, at-home study, the onset of action of vardenafil with subsequent intercourse completion was recognized as early as 10 minutes after dosing.

Adult↗
PubMed1981

Symptom relief and the placebo effect in the trial of an anti-peptic drug.

In order to determine some of the factors involved in the response of duodenal ulcers to placebo treatment, the following factors were studied prospectively during a double-blind, placebo-controlled trial: demographic data; duration of illness and effect of treatment; expectation of success or failure of the new drug; presence of psychiatric problems; and suggestibility. Healing (measured by endoscopy) occurred in 37 patients, 17 of whom were receiving placebo; relief of symptoms occurred in 35 patients, 16 of whom were receiving placebo. There was no significant difference between drug and placebo. Healing was significantly associated with relief of symptoms but with no other variable. Relief of symptoms was more common in male patients and in those from higher social classes, as well as in patients who expected a complete cure and those without evidence of psychiatric problems. the natural history of the disease may be different in these patients. Unexpectedly, suggestibility was not associated with healing or relief of symptoms in the patients receiving placebo.

Adult↗
PubMed2005

Placebo controlled, randomised, double blind study of the effects of botulinum A toxin on detrusor sphincter dyssynergia in multiple sclerosis patients.

OBJECTIVE: The purpose of the study was to evaluate the efficacy and safety of botulinum A toxin in the treatment of detrusor sphincter dyssynergia in multiple sclerosis patients. METHODS: This was a multicentre, placebo controlled, randomised, double blind study. Patients with chronic urinary retention were included if they had post-voiding residual urine volume between 100 and 500 ml. They received a single transperineal injection of either botulinum A toxin (100 U Allergan) or placebo in the sphincter and also 5 mg slow release alfuzosin bid over 4 months. Main endpoint was post-voiding residual urine volume assessed 1 month after injection. Follow up duration was 4 months. Statistical analysis was performed using a sequential method, the triangular test. RESULTS: The study was stopped after the fourth analysis (86 patients had been included: placebo: 41, botulinum A toxin: 45). At inclusion, there was no significant difference between groups whichever variable was considered. Mean (standard deviation) post-voiding residual urine volume was 217 (96) and 220 (99) ml in placebo and botulinum A toxin groups, respectively. One month later, post-voiding residual urine volume was 206 (145) and 186 (158) ml (p = 0.45) in placebo and botulinum A toxin groups, respectively. However, compared to placebo, botulinum A toxin significantly increased voiding volume (+54%, p = 0.02) and reduced pre-micturition (-29%, p = 0.02) and maximal (-21%, p = 0.02) detrusor pressures. Other secondary urodynamic endpoints and tolerance were similar in the two groups. CONCLUSIONS: In multiple sclerosis patients with detrusor sphincter dyssynergia, a single injection of botulinum A toxin (100 U Allergan) does not decrease post-voiding residual urine volume.

Botulinum Toxins, Type A↗
PubMed1991

Subcutaneous interferon alpha 2a combined with cryotherapy vs cryotherapy alone in the treatment of primary anogenital warts: a randomised observer blind placebo controlled study.

OBJECTIVE: To compare patient tolerance and treatment efficacy of subcutaneous interferon (IFN) alpha 2a plus cryotherapy versus cryotherapy alone in treatment of primary anogenital (AG) warts. DESIGN: Randomised placebo controlled observer blind study. Statistical analysis was by chi square and Mann Whitney U tests. PATIENTS: 60 patients with newly diagnosed AG warts. INTERVENTION: 29 and 31 patients were treated with subcutaneous IFN alpha 2a plus cryotherapy or placebo injections plus cryotherapy, respectively. MAIN OUTCOME MEASURES: Clinical presence or absence of AG warts. Patients wart-free at 8 weeks were asked to re-attend at 12 weeks; those with persistent warts at 8 weeks were withdrawn from the study. RESULTS: At 8 weeks 60.7% (17/28 patients) of the IFN group and 67.9% (19/28 patients) of the placebo group were clinically wart-free (not significant); corresponding figures at 12 week review were 29.6% (8/27 patients) and 40% (10/25 patients) respectively (not significant). There was no difference in treatment response between males and females. Recurrence of warts at three month review, in patients cleared of warts at 8 weeks, was seen in 50% (8/16) and 37.5% (6/16) of patients in the IFN and placebo groups respectively (not significant). Multiple warts and the presence of perianal/anal canal warts, either alone or concurrent with warts on the genitalia, at first clinic attendance, were adverse prognostic indicators (p less than 0.001, and p = 0.05 respectively). Cervical human papilloma virus (HPV) infection, exophytic or subclinical, was present in 58.3% and 77.2% of females in the IFN and placebo groups respectively, at trial entry. Although these lesions were not directly treated, colposcopic resolution was seen in 12.5% of affected women, in both treatment groups, by the end of the 7 week treatment period. Systemic side effects were significantly more common in the IFN than in the placebo group, 50% versus 10.7% of patients (p less than 0.01). Severe influenza like symptoms occurred, after the first three injections only, in one patient treated with IFN; all other reported side effects were mild. CONCLUSIONS: Subcutaneous IFN alpha 2a combined with cryotherapy is no more effective than cryotherapy alone in the treatment of primary AG warts. The presence of multiple warts and perianal/anal canal warts are adverse prognostic indicators.

Anus Diseases↗
PubMedDate not supplied

The problem of the placebo response in clinical trials for psychiatric disorders: culprits, possible remedies, and a novel study design approach.

The placebo response is a major issue in clinical trials for psychiatric disorders. Possible contributing factors to this problem include diagnostic misclassification, issues concerning inclusion/exclusion criteria, outcome measures' lack of sensitivity to change, measurement errors, poor quality of data entry and verification, waxing and waning of the natural course of illness, regression toward the mean phenomenon, patient and clinician expectations about the trial, study design issues, non-specific therapeutic effects, and high attrition. Over the past few decades, researchers have attempted to reduce the placebo effect in a variety of ways. Unfortunately, approaches with very little or no benefit have included restricting enrollment to selected populations, rater training, requirement of same rater, and placebo lead-in phases. Some benefits, although often marginal, have been derived from standardizing diagnostic procedures, managing clinicians' overestimation of change, simplification of study visits and assessments, minimizing non-specific, therapeutic effects, extending trial duration, reducing number of sites, increasing the sensitivity of outcome measures, and reducing the number of treatment arms. Thus far, there has been no attempt to develop new study designs aimed at reducing the placebo effect. We are proposing a novel study design, called 'Sequential Parallel Comparison Design', suitable for double-blind, placebo-controlled trials in psychiatric disorders. This design is aimed at reducing both the overall placebo response rate and the sample size required for such trials. Its usefulness in clinical research needs to be tested empirically. If this study design were to be found to meet its stated goals, this could markedly facilitate the process of clinical development of new compounds for the treatment of psychiatric disorders.

Clinical Trials as Topic↗
PubMed2004

Inhibition of (-)-trans-(1S,2S)-U50488 hydrochloride by its enantiomer in white mice -- a placebo-controlled, randomized study.

BACKGROUND: Previous studies have been performed to see if toxicity of optically active compounds may be inhibited by potentized preparations of their enantiomers. The present study is based on the hypothesis that the toxic effects of an optical isomer may be counteracted or reversed by the administration of a potentized preparation of one of its stereoisomers and in particular the enantiomer (patent applied for). METHODS: The design was prospective, blind, randomized, and placebo-controlled. 210 ICR conventional mice were used. 105 mice were administered a mixture of (+)-U50488 hydrochloride homeopathic potencies prior to and during the experiment, and the other 105 were administered indistinguishable placebo. The first 52 mice were used to establish an LD(50) of intraperitoneally administered (-)-U50488 hydrochloride under the conditions of this experiment. The estimated LD(50) was 25 mg/kg. The remaining 158 mice were then administered this LD(50) of (-)-U50488 HCl intraperitoneally. One mouse from the placebo group was excluded from the analysis because it died immediately after the possibly intravenous injection of (-)-U50488 HCl. RESULTS: 67% of homeopathy mice survived compared with 47% of placebo mice. The end point for statistical analysis was the difference in survival between the placebo and homeopathy mice. The analysis was adjusted for mouse weight using a logistic regression (LR) model. The LR treatment odds ratio for survival of treatment mice relative to placebo mice was 2.301 and the LR treatment chi-square was 6.2030 (1 degree of freedom), which has a p-value of 0.0128. Consequently, we reject the null hypothesis of no treatment effect on survival. CONCLUSION: We conclude that toxicity of intraperitoneal injection of (-)-U50488 hydrochloride may be inhibited by administration of a mixture of potencies of its enantiomer.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMed1984

Nifedipine therapy for patients with threatened and acute myocardial infarction: a randomized, double-blind, placebo-controlled comparison.

Preliminary clinical and laboratory observations suggest that nifedipine might prevent progression of threatened myocardial infarction by reversing coronary spasm or might limit necrosis during the course of acute myocardial infarction. We screened 3143 patients with ischemic pain of greater than 45 min duration and randomly assigned 105 eligible patients with threatened myocardial infarction and 66 with acute myocardial infarction to receive nifedipine (20 mg orally every 4 hr for 14 days) or placebo plus standard care. Treatment was started 4.6 +/- 0.1 hr after the onset of pain. Infarct size index was calculated by the MB-creatine kinase (CK) method and expressed as CK-geq/m2 +/- SE. The incidence of progression to infarction among patients with threatened myocardial infarction was not significantly altered by nifedipine (36 of 48 [75%] for placebo-treated and 43 of 57 [75%] for nifedipine-treated patients). Furthermore, infarct size index was similar among placebo- and nifedipine-treated patients (16.9 +/- 1.5 MB-CK-geq/m2, n = 65, and 17.0 +/- 1.5 MB-CK-geq/m2, n = 68, respectively) with threatened myocardial infarction who exhibited infarction and for those with acute myocardial infarction. Among the 171 eligible patients randomly assigned to drug or placebo, 6 month mortality did not differ significantly (8.5% for placebo vs 10.1% for nifedipine, NS), but mortality in the 2 weeks after randomization was significantly higher for nifedipine-treated patients (0% for placebo compared with 7.9% for nifedipine, p = .018).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

A double-blind, placebo-controlled study of ketanserin in patients with Prinzmetal's angina. Evidence against a role for serotonin in the genesis of coronary vasospasm.

This study was designed to test the hypothesis of a possible role of serotonin in the pathogenesis of myocardial ischemia in patients with pure vasospastic angina, since serotonin is known to cause contraction in isolated coronary arteries. This effect, as well as serotonin-induced platelet aggregation, is reversed by ketanserin, a specific S2-receptor blocker. Five male patients (49 to 68 years old) with more than six episodes/day of myocardial ischemia at rest as characterized by ST segment elevation on the electrocardiogram (ECG) were selected for the study after a 2 day run-in period of continuous ECG Holter monitoring in the absence of any therapy except that with sublingual nitrates. In a double-blind crossover protocol they received consecutive infusions of 6 hr each of ketanserin (2 mg/hr iv, preceded by a 10 mg bolus in three patients) and placebo in the following sequence: ketanserin-placebo-ketanserin-placebo in the first and placebo-ketanserin-placebo-ketanserin in the second 24 hr period. The efficacy of the infused drug was tested by exposing platelet-rich plasma, obtained from the study patients at a fixed morning time before and during ketanserin infusions, to a series of serotonin concentrations from 10(-5) to 10(-8)M in a conventional aggregometer. A complete suppression of aggregation curves in the range of serotonin concentrations tested resulted during administration of ketanserin. The efficacy of the drug in preventing ischemic episodes was assessed by computing the ischemic episodes (recorded by Holter monitoring) and nitroglycerin consumption in each 6 hr ketanserin period and in the corresponding placebo period. A total of 171 ischemic episodes were recorded, 33 of which (19%) were symptomatic.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1987

A randomized, blinded, placebo-controlled trial of recombinant human tissue-type plasminogen activator in patients with unstable angina pectoris.

Twenty-four patients with unstable angina pectoris, defined as chest pain at rest with transient ST segment deviation of at least 1 mm, were randomly assigned to blinded treatment with either placebo or intravenous recombinant human tissue-type plasminogen activator (rt-PA). Before randomization, all patients were treated with oral beta-blockers, calcium antagonists, nitrates, and continuous intravenous heparin for a monitoring period of 12 to 28 hr. After this monitoring period the 24 patients were randomly assigned to receive either placebo or 1.75 mg/kg intravenous rt-PA given over 12 hr at a rate of 0.75 mg/kg over 1 hr, 0.5 mg/kg over 4 hr, and 0.5 mg/kg over 7 hr. One patient, assigned to receive placebo, developed acute myocardial infarction after randomization but before receiving the study drug. Ischemic events were recorded during a hospital follow-up period of at least 4 days unless a further intervention was indicated or the coronary angiogram was normal. The follow-up period was 7 +/- 5 days (mean +/- SD) after the placebo infusion and 8 +/- 4 days after the infusion of rt-PA. Unstable angina pectoris persisted after the completion of the infusion in six of 11 patients receiving placebo and only one of 12 patients receiving rt-PA (p less than .03). Coronary angiography, performed 38 +/- 19 hr after the infusion, demonstrated subocclusive thrombus in eight of 11 patients receiving placebo but in none of 11 patients treated with rt-PA (p less than .002). One patient on rt-PA refused coronary angiography.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗
PubMed1997

Placebo-controlled biofeedback blood pressure effect in hypertensive humans.

The role of biofeedback in blood pressure control remains ill-defined because of nonspecific (placebo) effects, small study numbers, and the technical limitations of continuous pressure feedback. Clarification of its potential is awaited by those seeking a nonpharmacological approach to blood pressure control. This study examines the capability for systolic pressure lowering of 5 mm Hg or more using continuous pressure feedback in a statistical sample of untreated, well-characterized, mildly hypertensive individuals. Subjects were randomized in a double-blind study to active or placebo biofeedback. Placebo consisted of a modified contingency approach, using a partial disguise based on a digital high pass filter with 15 elements. Blood pressure-lowering capability was assessed during two laboratory sessions. Continuous visual feedback resulted in 11 of 28 subjects on active treatment and 12 of 28 on placebo treatment lowering their systolic pressure by 5 mm Hg or more (11 +/- 5.6 and 12 +/- 8.4 mm Hg, respectively; P = NS). Prestudy pressure was well-matched (153 +/- 9/97 +/- 4 and 154 +/- 8/98 +/- 4 mm Hg, respectively). An initial small difference in diurnal profile did not change. These findings indicate that among mildly hypertensive individuals, almost half can lower systolic pressure at will for short periods. This capability is independent of the real or placebo nature of the feedback signal. We conclude that there is no specific short-term biofeedback pressure-lowering capability in hypertensive individuals. Further exploration is needed to determine whether specific components of the placebo effect can be delineated, whether personality characteristics influence the response, and whether further biofeedback training can alter the outcome.

Adult↗
PubMed1987

Double-blind, placebo-controlled trial of potassium chloride in the treatment of mild hypertension.

Epidemiological and experimental data suggest blood pressure-lowering effects of dietary potassium. A randomized, double-blind clinical trial was used to assess blood pressure response to orally administered potassium, 120 mEq/day, and to placebo in 101 adults with mild hypertension. Blood pressure was measured with a random-zero sphygmomanometer every 2 weeks of this 8-week trial. Systolic blood pressure in the potassium-treated group decreased by 6.4 +/- 13.7 (SD) mm Hg (p less than or equal to 0.025) compared with 0.11 +/- 13.0 mm Hg in the placebo-treated group (p = 0.96). Diastolic blood pressure in the potassium-treated group decreased by 4.1 +/- 8.3 mm Hg (p less than or equal to 0.05) compared with a 1.6 +/- 6.5 mm Hg decrease in placebo-treated subjects (p = 0.09). Baseline blood pressure of potassium-treated subjects was unexpectedly higher than that of controls. After correcting for baseline variation, blood pressure still decreased 3.4/1.8 mm Hg more in potassium recipients than in placebo recipients (p = 0.14 and 0.24, respectively). Blood pressure decreased by 19/13 mm Hg in five blacks taking potassium versus a 1/0 mm Hg increase in seven blacks taking placebo. Compliance with the potassium regimen was 91.5% by pill count; only one subject discontinued treatment because of side effects. In conclusion, 120 mEq/day of microencapsulated potassium chloride was well tolerated in adults with mild hypertension. An antihypertensive effect of potassium cannot be ruled out despite the fact that there was no statistically significant difference between potassium-treated and placebo-treated subjects after adjustment for differences in baseline blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2000

Nortriptyline versus fluoxetine in the treatment of depression and in short-term recovery after stroke: a placebo-controlled, double-blind study.

OBJECTIVE: This study compared nortriptyline and fluoxetine with placebo in the treatment of depression and in recovery from physical and cognitive impairments after stroke. METHOD: A total of 104 patients with acute stroke enrolled between 1991 and 1997 entered a double-blind randomized study comparing nortriptyline, fluoxetine, and placebo over 12 weeks of treatment. The majority of patients were recruited from a rehabilitation hospital in Des Moines, Iowa, but other enrollment sites were also used. Both depressed and nondepressed patients were enrolled to determine whether improved recovery could be mediated by mechanisms unrelated to depression. Nortriptyline in doses of 25 mg/day gradually increased to 100 mg/day or fluoxetine in doses of 10 mg/day gradually increased to 40 mg/day or identical placebo were given over 12 weeks. Response to treatment of depression for individual patients was defined as a greater-than-50% reduction in scores on the Hamilton Rating Scale for Depression and no longer fulfilling diagnostic criteria for major or minor depression. Improved recovery for a treatment group was defined as a significantly higher mean score from baseline to end of the treatment trial, compared with patients treated with placebo, on measures of impairment in activities of daily living and levels of cognitive and social functioning. RESULTS: Nortriptyline produced a significantly higher response rate than fluoxetine or placebo in treating poststroke depression, in improving anxiety symptoms, and in improving recovery of activities of daily living as measured by the Functional Independence Measure. There was no effect of nortriptyline or fluoxetine on recovery of cognitive or social functioning among depressed or nondepressed patients. Fluoxetine in increasing doses of 10-40 mg/day led to an average weight loss of 15. 1 pounds (8% of initial body weight) over 12 weeks of treatment that was not seen with nortriptyline or placebo. CONCLUSIONS: Given the doses of medication used in this study, nortriptyline was superior to fluoxetine in the treatment of poststroke depression. Demonstrating a benefit of antidepressant treatment in recovery from stroke may require the identification of specific subgroups of patients, alternative measurement scales, or the optimal time of treatment.

Activities of Daily Living↗
PubMed2001

Sertraline treatment of generalized social phobia: a 20-week, double-blind, placebo-controlled study.

OBJECTIVE: The authors evaluated the efficacy, safety, and tolerability of sertraline, a selective serotonin reuptake inhibitor, in the treatment of generalized social phobia. METHOD: Adult outpatients with generalized social phobia (N=204) from 10 Canadian centers were randomly assigned to receive sertraline or placebo in a 2:1 ratio for a 20-week double-blind study following a 1-week, single-blind, placebo run-in. The initial dose of sertraline was 50 mg/day with increases of 50 mg/day every 3 weeks permitted after the fourth week of treatment (dosing was flexible up to a maximum of 200 mg/day). Primary efficacy assessments were the percentage of patients rated much or very much improved on the Clinical Global Impression (CGI) improvement item and the mean changes from baseline to study endpoint in total score on the social phobia subscale of the Marks Fear Questionnaire and total score on the Brief Social Phobia Scale. RESULTS: In intent-to-treat endpoint analyses of 203 of the patients, significantly more of the 134 patients given sertraline (N=71 [53%]) than of the 69 patients receiving placebo (N=20 [29%]) were considered responders according to their CGI improvement scores at the end of treatment. The mean reductions in the social phobia subscale of the Marks Fear Questionnaire and in the total score on the Brief Social Phobia Scale were 32.6% and 34.3% in the sertraline group and 10.8% and 18.6% in the placebo group, respectively. Analysis of covariance showed superiority of sertraline over placebo on all primary and secondary efficacy measures. Sertraline was well tolerated: 103 (76%) of the 135 sertraline-treated patients and 54 (78%) of the 69 placebo-treated patients completed the study. CONCLUSIONS: Sertraline is an effective treatment for patients with generalized social phobia.

Adult↗
PubMed2001

A placebo-controlled study of guanfacine in the treatment of children with tic disorders and attention deficit hyperactivity disorder.

OBJECTIVE: This study evaluated the efficacy and safety of guanfacine in treating children with tic disorders and attention deficit hyperactivity disorder (ADHD). METHOD: Subjects from a specialty tic disorders clinic were randomly assigned to receive 8 weeks of treatment with guanfacine or placebo under double-blind conditions. Follow-up visits occurred every 2 weeks for safety monitoring and dose adjustment. RESULTS: Thirty-four medication-free subjects (31 boys and three girls with a mean age of 10.4 years) with ADHD, combined type, and a tic disorder participated. After 8 weeks of treatment, guanfacine was associated with a mean improvement of 37% in the total score on the teacher-rated ADHD Rating Scale, compared to 8% improvement for placebo. Nine of 17 subjects who received guanfacine were blindly rated on the Clinical Global Improvement scale as either much improved or very much improved, compared with none of 17 subjects who received placebo. The mean score on the parent-rated hyperactivity index improved by 27% in the guanfacine group and 21% in the placebo group, not a significant difference. On the Continuous Performance Test, commission errors decreased by 22% and omission errors by 17% in the guanfacine group, compared with increases of 29% in commission errors and of 31% in omission errors in the placebo group. Tic severity decreased by 31% in the guanfacine group, compared to 0% in the placebo group. One guanfacine subject with sedation withdrew at week 4. Guanfacine was associated with insignificant decreases in blood pressure and pulse. CONCLUSIONS: Guanfacine appears to be a safe and effective treatment for children with tic disorders and ADHD.

Adolescent↗