Effect of creatine monohydrate on clinical progression in patients with Parkinson disease: a randomized clinical trial

IMPORTANCE

There are no treatments available to slow or prevent the progression of Parkinson disease, despite its global prevalence and significant health care burden. The National Institute of Neurological Disorders and Stroke Exploratory Trials in Parkinson Disease program was established to promote discovery of potential therapies.

OBJECTIVE

To determine whether creatine monohydrate was more effective than placebo in slowing long-term clinical decline in participants with Parkinson disease.

DESIGN, SETTING, AND PATIENTS

The Long-term Study 1, a multicenter, double-blind, parallel-group, placebo-controlled, 1:1 randomized efficacy trial. Participants were recruited from 45 investigative sites in the United States and Canada and included 1741 men and women with early (within 5 years of diagnosis) and treated (receiving dopaminergic therapy) Parkinson disease. Participants were enrolled from March 2007 to May 2010 and followed up until September 2013.

INTERVENTIONS

Participants were randomized to placebo or creatine (10 g/d) monohydrate for a minimum of 5 years (maximum follow-up, 8 years).

MAIN OUTCOMES AND MEASURES

The primary outcome measure was a difference in clinical decline from baseline to 5-year follow-up, compared between the 2 treatment groups using a global statistical test. Clinical status was defined by 5 outcome measures: Modified Rankin Scale, Symbol Digit Modalities Test, PDQ-39 Summary Index, Schwab and England Activities of Daily Living scale, and ambulatory capacity. All outcomes were coded such that higher scores indicated worse outcomes and were analyzed by a global statistical test. Higher summed ranks (range, 5-4775) indicate worse outcomes.

RESULTS

The trial was terminated early for futility based on results of a planned interim analysis of participants enrolled at least 5 years prior to the date of the analysis (n = 955). The median follow-up time was 4 years. Of the 955 participants, the mean of the summed ranks for placebo was 2360 (95% CI, 2249-2470) and for creatine was 2414 (95% CI, 2304-2524). The global statistical test yielded t1865.8 = -0.75 (2-sided P = .45). There were no detectable differences (P < .01 to partially adjust for multiple comparisons) in adverse and serious adverse events by body system.

CONCLUSIONS AND RELEVANCE

Among patients with early and treated Parkinson disease, treatment with creatine monohydrate for at least 5 years, compared with placebo did not improve clinical outcomes. These findings do not support the use of creatine monohydrate in patients with Parkinson disease.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00449865.

A randomized clinical trial of high-dosage coenzyme Q10 in early Parkinson disease: no evidence of benefit

IMPORTANCE

Coenzyme Q10 (CoQ10), an antioxidant that supports mitochondrial function, has been shown in preclinical Parkinson disease (PD) models to reduce the loss of dopamine neurons, and was safe and well tolerated in early-phase human studies. A previous phase II study suggested possible clinical benefit.

OBJECTIVE

To examine whether CoQ10 could slow disease progression in early PD.

DESIGN, SETTING, AND PARTICIPANTS

A phase III randomized, placebo-controlled, double-blind clinical trial at 67 North American sites consisting of participants 30 years of age or older who received a diagnosis of PD within 5 years and who had the following inclusion criteria: the presence of a rest tremor, bradykinesia, and rigidity; a modified Hoehn and Yahr stage of 2.5 or less; and no anticipated need for dopaminergic therapy within 3 months. Exclusion criteria included the use of any PD medication within 60 days, the use of any symptomatic PD medication for more than 90 days, atypical or drug-induced parkinsonism, a Unified Parkinson's Disease Rating Scale (UPDRS) rest tremor score of 3 or greater for any limb, a Mini-Mental State Examination score of 25 or less, a history of stroke, the use of certain supplements, and substantial recent exposure to CoQ10. Of 696 participants screened, 78 were found to be ineligible, and 18 declined participation.

INTERVENTIONS

The remaining 600 participants were randomly assigned to receive placebo, 1200 mg/d of CoQ10, or 2400 mg/d of CoQ10; all participants received 1200 IU/d of vitamin E.

MAIN OUTCOMES AND MEASURES

Participants were observed for 16 months or until a disability requiring dopaminergic treatment. The prospectively defined primary outcome measure was the change in total UPDRS score (Parts I-III) from baseline to final visit. The study was powered to detect a 3-point difference between an active treatment and placebo.

RESULTS

The baseline characteristics of the participants were well balanced, the mean age was 62.5 years, 66% of participants were male, and the mean baseline total UPDRS score was 22.7. A total of 267 participants required treatment (94 received placebo, 87 received 1200 mg/d of CoQ10, and 86 received 2400 mg/d of CoQ10), and 65 participants (29 who received placebo, 19 who received 1200 mg/d of CoQ10, and 17 who received 2400 mg/d of CoQ10) withdrew prematurely. Treatments were well tolerated with no safety concerns. The study was terminated after a prespecified futility criterion was reached. At study termination, both active treatment groups showed slight adverse trends relative to placebo. Adjusted mean changes (worsening) in total UPDRS scores from baseline to final visit were 6.9 points (placebo), 7.5 points (1200 mg/d of CoQ10; P = .49 relative to placebo), and 8.0 points (2400 mg/d of CoQ10; P = .21 relative to placebo).

CONCLUSIONS AND RELEVANCE

Coenzyme Q10 was safe and well tolerated in this population, but showed no evidence of clinical benefit.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00740714.

A double-blind placebo-controlled pilot study of controlled-release paroxetine on depression and quality of life in chronic heart failure

BACKGROUND

Depression is frequently observed in patients with heart failure and is associated with poor quality of life and adverse prognosis. However, the prevalence of depression in heart failure could be overestimated because symptoms of depression overlap with those of heart failure. Similarly, the importance of depression may be overestimated if depression merely reflects worse heart failure. Because the response to depression treatment has not been evaluated in this patient population, we evaluated the efficacy of controlled-release paroxetine (paroxetine CR), a selective serotonin reuptake inhibitor, on depression and quality of life in chronic heart failure.

METHODS

A double-blind, randomized, placebo-controlled design was used to evaluate reductions in depression following 12 weeks of treatment with paroxetine CR (n = 14, age 62.1 +/- 12.3 years) or placebo (n = 14, age = 61.9 +/- 9.0 years). Patients with symptomatic congestive heart failure and a score of at least 10 on the Beck Depression Inventory (BDI) were eligible. Beck Depression Inventory was obtained at baseline and 4, 8, and 12 weeks of follow-up. Quality of life was assessed using the Medical Outcomes Study Short Form and the Minnesota Living with Heart Failure Questionnaire.

RESULTS

Controlled-release paroxetine resulted in significantly more recovery from depression (BDI <10) than placebo (69% vs 23%, P = .018) and resulted in lower continuous BDI scores throughout the intervention (P = .024). Controlled-release paroxetine was associated with higher general health levels compared with placebo on the Medical Outcomes Study 36-Item Short Form survey (38 +/- 10 vs 30 +/- 6, P = .016) at 12 weeks of follow-up. Reductions in depression were correlated with improvements in psychological aspects of quality of life (P < .05) but not with physical quality of life measures (P > .10).

CONCLUSION

Antidepressant therapy with paroxetine CR results in significant reductions in depression among patients with heart failure. The reductions in depression with paroxetine CR are accompanied by improvements in psychological aspects of quality of life. Larger controlled trials are needed to further document the effectiveness of paroxetine CR and other selective serotonin reuptake inhibitors in patients with heart failure and to determine patient subgroups that are most likely to benefit from antidepressive interventions.

Effects of BG9719 (CVT-124), an A1-adenosine receptor antagonist, and furosemide on glomerular filtration rate and natriuresis in patients with congestive heart failure

OBJECTIVES

To determine the effects of furosemide and the selective A1 adenosine receptor BG9719 on renal function in patients with congestive heart failure (CHF).

BACKGROUND

Studies suggest that adenosine may affect renal function by various mechanisms, but the effects of blockade of this system in humans is unknown. In addition, the effects of a therapeutic dose of furosemide on glomerular filtration rate (GFR) and renal plasma flow (RPF) in heart failure patients are controversial.

METHODS

On different days, 12 patients received placebo, BG9719 and furosemide. Glomerular filtration rate, RPF and sodium and water excretion were assessed immediately following drug administration.

RESULTS

Glomerular filtration rate was 84 +/- 23 ml/min/1.73m2 after receiving placebo, 82 +/- 24 following BG9719 administration and a decreased (p < 0.005) 63 +/- 18 following furosemide. Renal plasma flow was unchanged at 293 +/- 124 ml/min/1.73m2 on placebo, 334 +/- 155 after receiving BG9719 and 374 +/- 231 after receiving furosemide. Sodium excretion increased from 8 +/- 8 mEq following placebo administration to 37 +/- 26 mEq following BG9719 administration. In the six patients in whom it was measured, sodium excretion was 104 +/- 78 mEq following furosemide administration.

CONCLUSIONS

Natriuresis is effectively induced by both furosemide and the adenosine A1 antagonist BG9719 in patients with CHF. Doses of the two drugs used in this study did not cause equivalent sodium and water excretion but only furosemide decreased GFR. These data suggest that adenosine is an important determinant of renal function in patients with heart failure.

Torsades de pointes with administration of high-dose intravenous d-sotalol to a patient with congestive heart failure

A patient with heart failure was administered d-sotalol 3.0 mg/kg infused over 2 minutes. The patient had normal electrolytes and baseline QT. Six minutes after drug administration the QT prolonged to 600 msec, and the patient developed torsades de pointes and required electrical cardioversion. This emphasizes the need to consider both rate of administration and the dosage when evaluating the safety and efficacy of a new class III antiarrhythmic drug.

The hemodynamic actions of the antiarrhythmic agent ipazilide fumarate in patients with congestive heart failure

Ipazilide fumarate is an investigational antiarrhythmic agent with Vaughan Williams class I and III actions, including prolongation of both ventricular refractoriness and action potential duration. Because of the frequent use of antiarrhythmic agents in patients with heart failure, we investigated the hemodynamic effects of oral administration of 400, 200, and 100 mg of ipazilide fumarate in 15 patients with congestive heart failure. There was a marked hemodynamic response to ipazilide, with the peak effect noted 2 hours after drug administration. In patients who received 400 mg ipazilide, the mean cardiac index was decreased by 0.5 L/min/m2 at 2 hours (p < 0.05). After 200 and 100 mg ipazilide, the decreases were a more modest 0.3 and 0.1 L/min/m2, respectively. The mean arterial pressure also decreased in a dose- and time-dependent manner, although this did not reach statistical significance for any of the doses. Left ventricular filling pressure, right atrial pressure, and heart rate were not altered by ipazilide. Plasma concentrations of ipazilide peaked 90 minutes after administration of 100 or 200 of the drug, but peak concentrations were noted 3 hours after administration of 400 mg. The hemodynamic response correlated with the plasma concentration of ipazilide determined contemporaneously. We conclude that, as with most antiarrhythmic agents, single-dose administration of ipazilide fumarate can cause clinically significant hemodynamic deterioration.

High dose oral amiodarone loading exerts important hemodynamic actions in patients with congestive heart failure

OBJECTIVES

The purpose of this study was to use invasive monitoring to analyze the hemodynamic effects of both a large single dose and a 48-h loading regimen of amiodarone in patients with severe heart failure.

BACKGROUND

Amiodarone is frequently used as an antiarrhythmic agent in patients with congestive heart failure, but the impact of this agent on cardiac function remains controversial. Recent successful experience with a rapid oral load of amiodarone makes invasive testing of the hemodynamic effects of oral amiodarone in such patients now feasible.

METHODS

After baseline hemodynamic assessment (using balloon-tipped pulmonary artery catheters) and electrocardiographic measurements, 16 patients received 12.5 mg/kg body weight of amiodarone orally. Hemodynamic measurements were obtained hourly for 4 h. Patients then received this dose an additional seven times over the next 2 days. Hemodynamic variables and QRS, QT and PR intervals were measured after 48 h of treatment.

RESULTS

Vasodilation was seen between 1 and 3 h after drug administration. Systemic vascular resistance decreased 326 +/- 135 dynes.s.cm-5, cardiac index increased 0.24 +/- 0.08 liters/min per m2 and mean arterial pressure decreased 6 +/- 3 mm Hg (mean +/- SEM, all p < 0.05). After 48 h of amiodarone administration, heart rate decreased 23 +/- 3 beats/min (p < 0.005), stroke volume increased 9 +/- 3 ml (p < 0.005), cardiac index decreased 0.23 +/- 0.09 ml/min per m2 (p < 0.05), pulmonary capillary wedge pressure increased 4 +/- 1 mm Hg (p < 0.01), right atrial pressure increased 3 +/- 1 mm Hg (p < 0.005) and QT and PR intervals were markedly prolonged (p < 0.01).

CONCLUSIONS

Although the first dose caused vasodilation, a complete loading regimen of amiodarone produced a decreased heart rate with elevated filling pressures and decreased cardiac index.

Sustained hemodynamic response to flosequinan in patients with heart failure receiving angiotensin-converting enzyme inhibitors

OBJECTIVES

We evaluated the short- and long-term effects of flosequinan in 47 patients with severe heart failure despite ongoing captopril treatment.

BACKGROUND

There have been no previous evaluations of the long-term hemodynamic effects of any direct-acting vasodilator in patients with heart failure receiving an angiotensin-converting enzyme inhibitor. Flosequinan is an arterial and venous vasodilator with actions similar to those of the hydralazine-isosorbide dinitrate combination.

METHODS

After baseline hemodynamic measurements using balloon-tipped pulmonary artery and radial arterial catheters, patients were randomized to receive 50, 100 or 150 mg of flosequinan daily. Hemodynamic variables were measured immediately before and after short-term flosequinan administration and after 8 weeks of therapy.

RESULTS

With short-term flosequinan administration, mean arterial, right atrial and left ventricular filling pressures decreased by 6.4 +/- 1.1, 3.8 +/- 0.5 and 7.3 +/- 0.7 mm Hg, respectively (all p < 0.001). Cardiac index increased by 0.5 +/- 0.1 liters/min per m2, systemic vascular resistance decreased by 616 +/- 105 dynes.s.cm-5 and heart rate increased by 4 +/- 1 beats/min (all p < 0.001). After 8 weeks of long-term flosequinan administration, the vasodilator effect of a dose of flosequinan persisted. Compared with pretreatment baseline values, mean arterial, right atrial and left ventricular filling pressures at the peak effect of flosequinan were decreased by 3.5 +/- 1.3, 2.8 +/- 0.7 and 5.1 +/- 1.3 mm Hg, respectively (all p < 0.01). Systemic vascular resistance had decreased by 585 +/- 95 dynes.s.cm-5, cardiac index had increased by 0.5 +/- 0.1 liters/min per m2 and heart rate had increased by 10 +/- 2 beats/min (all p < 0.001).

CONCLUSIONS

The arterial and venous vasodilator flosequinan exerts both short- and long-term sustained hemodynamic effects in patients with heart failure receiving angiotensin-converting enzyme inhibitors.