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Ian Hindmarch

Publications and source records attributed to Ian Hindmarch.

At least 19 recordsLinked to original sources
PubMed2006

A double-blind, randomized, parallel-group, flexible-dose study to evaluate the tolerability, efficacy and effects of treatment discontinuation with escitalopram and paroxetine in patients with major depressive disorder.

This multinational, randomized, double-blind, flexible-dose study evaluated the short- and long-term antidepressant tolerability and efficacy of escitalopram and paroxetine. Tolerability was assessed by monitoring adverse events throughout the study, and discontinuation events during brief treatment interruption and tapered withdrawal. Discontinuation-emergent effects were evaluated in two separate double-blind periods. First, to mimic the consequences of non-compliance, patients were randomized to one of two treatment interruption periods (placebo-substitution for 3-5 days). Second, patients were randomized to a 1-2-week tapered withdrawal period randomly scheduled between weeks 28 and 31. The pre-specified primary efficacy endpoint was the mean change from baseline in total Montgomery-Asberg Depression Rating Scale (MADRS) score at week 8, using the principle of last observation carried forward. A total of 323 patients entered 8 weeks of double-blind treatment and received at least one flexible dose of escitalopram (10-20 mg/day) or paroxetine (20-40 mg/day). Patients who demonstrated evidence of a significant clinical improvement (Clinical Global Impression-Improvement of 1 or 2) at week 8 entered a 19-week, double-blind maintenance period during which they were treated with the same dose they received at week 8, followed by a 1-2-week tapered withdrawal period. A total of 89 patients (28%) withdrew during the study; significantly (P<0.01) more patients withdrew from the paroxetine group (34%) than from the escitalopram group (21%), and significantly (P<0.05) more paroxetine patients withdrew due to lack of efficacy. The mean MADRS total score improved for both treatment groups from baseline to week 8, with no statistical difference between groups. In severely depressed patients (baseline MADRS total score >or=30), escitalopram was superior (P<0.05) to paroxetine at week 27 (end of maintenance treatment). There was a high prevalence of sexual dysfunction at baseline: the mean Arizona Sexual Experience Scale (ASEX) score was approximately 20 points in both treatment groups. Mean total ASEX scores increased slightly above baseline values during the acute period and declined slightly below baseline values towards the end of the maintenance period. During taper and cessation of treatment, patients in the paroxetine group demonstrated significantly more discontinuation symptoms relative to escitalopram based on the Discontinuation Emergent Signs and Symptoms scores.

Citalopram↗
PubMed2006

A double-blind, placebo-controlled investigation of the residual psychomotor and cognitive effects of zolpidem-MR in healthy elderly volunteers.

AIM: To assess residual psychomotor and cognitive effects of a modified-release formulation of zolpidem (zolpidem-MR), developed to provide sustained hypnotic efficacy during the whole night, compared with placebo and flurazepam. METHODS: Twenty-four healthy elderly volunteers received four study treatments (zolpidem-MR 6.25 mg and 12.5 mg, placebo and flurazepam 30 mg) using a randomized, cross-over, double-blind design. Residual psychomotor and cognitive effects were assessed with a psychometric test battery. Quality of sleep and residual effects were evaluated subjectively with the Leeds Sleep Evaluation Questionnaire. RESULTS: Psychometric performance was significantly impaired with flurazepam but not with zolpidem-MR at either dose. Ease of falling asleep and sleep quality were significantly improved with both doses of zolpidem-MR and with flurazepam. Neither active drug modified perception of well-being on awakening. CONCLUSION: In elderly subjects, zolpidem-MR showed no residual functional impairment in psychometric or cognitive tests sensitive to flurazepam.

Adult↗
PubMed2005

A double-blind, placebo- and positive-internal-controlled (alprazolam) investigation of the cognitive and psychomotor profile of pregabalin in healthy volunteers.

RATIONALE: Pregabalin potently and selectively binds to the alpha(2)-delta subunit of voltage-dependent calcium channels, reducing calcium influx and modulating release of downstream excitatory neurotransmitters, such as glutamate. Pregabalin has demonstrated robust efficacy for several disease states, but its neuropharmacology is still being elucidated. OBJECTIVE: This study was conducted to evaluate the cognitive and psychomotor effects of oral pregabalin (150 mg t.i.d.) using alprazolam (1 mg t.i.d.) as a positive internal control and placebo. METHODS: Twenty-four healthy volunteers were randomised to a double-blind, three-way crossover study. Each period consisted of 3-day double-blind treatment followed by 1 day of single-blind placebo. Psychometrics included tests of Choice Reaction Time (CRT), CNS arousal (Critical Flicker Fusion, CFF), vigilance (Rapid Visual Information Processing, RVIP), serial memory scanning (Sternberg Short-Term Memory Scanning Test, STM), divided attention (Compensatory Tracking Task, CTT), Brake Reaction Time (BRT) in an on-the-road vehicle, and subjective Line Analogue Rating Scales (LARS) for sedation. RESULTS: Pregabalin showed no significant effects on the objective psychometrics-CRT, BRT, RVIP, STM-compared with placebo. Pregabalin produced a limited, significant decrement on CFF and CTT and a significant effect on the LARS. Pregabalin was associated with improvement relative to placebo in BRT. The positive control, alprazolam, produced significant impairment on all objective measures and significant impairment on the LARS, thus establishing the sensitivity of the test battery used in the study. CONCLUSIONS: Pregabalin did not differ on most assessments from placebo, producing only minor, transient impairment on some objective cognitive and psychomotor measures, suggesting a relatively benign CNS side-effect profile.

Alprazolam↗
PubMed2005

Effects of fexofenadine and hydroxyzine on brake reaction time during car-driving with cellular phone use.

Antihistamines are a mainstay treatment for allergic rhinitis; however, many older agents cause adverse events, including sedation and central nervous system (CNS) impairment. Research has shown sedating effects of antihistamines on driving; currently, no known study has examined whether cellular phone usage while driving further compounds impairment in individuals administered antihistamines. The aim of this study was to examine this endpoint. In a randomized, double-blind, placebo-controlled, three-way crossover study, healthy volunteers received fexofenadine HCl 120 mg, hydroxyzine HCl 30 mg and placebo. Brake reaction time (BRT) was used to examine driving performance across four conditions: driving only; driving while completing simple calculations; complex calculations; and conversing on a cellular phone. Subjective sedation assessments were also conducted. Brake reaction time with and without cellular phone usage in fexofenadine-treated subjects did not differ significantly from placebo in any condition. In contrast, hydroxyzine-treated subjects were significantly more sedated and had slower BRTs, suggesting slower hazard recognition and brake application, compared with the fexofenadine and placebo groups in all conditions. Importantly, cellular phone operation was an additive factor, increasing BRTs in hydroxyzine-treated volunteers. Fexofenadine did not impair CNS function in subjects involved in a divided attention task of driving and cellular phone operation.

Adult↗
PubMed2005

A double-blind study in healthy volunteers to assess the effects on sleep of pregabalin compared with alprazolam and placebo.

STUDY OBJECTIVES: To assess the effects of pregabalin compared with alprazolam and placebo on aspects of sleep in healthy volunteers. DESIGN: Randomized, double-blind, placebo- and active-controlled, 3-way crossover. SETTING: Single research center. PARTICIPANTS AND INTERVENTIONS: Healthy adult (12 men) volunteers (N=24) received oral pregabalin 150 mg t.i.d., alprazolam 1 mg t.i.d., and placebo t.i.d. for 3 days. MEASUREMENTS AND RESULTS: Objective sleep was measured by an 8-channel polysomnograph; subjective sleep was measured using the Leeds Sleep Evaluation Questionnaire. Compared with placebo, pregabalin significantly increased slow-wave sleep both as a proportion of the total sleep period and the duration of stage 4 sleep. Alprazolam significantly reduced slow-wave sleep. Pregabalin and alprazolam produced modest, but significant, reductions in sleep-onset latency compared with placebo. Rapid eye movement sleep latency after pregabalin was no different than placebo but was significantly shorter than that found with alprazolam. Although there were no differences between the active treatments, both pregabalin and alprazolam reduced rapid eye movement sleep as a proportion of the total sleep period compared with placebo. Pregabalin also significantly reduced the number of awakenings of more than 1 minute in duration. Leeds Sleep Evaluation Questionnaire ratings of the ease of getting to sleep and the perceived quality of sleep were significantly improved following both active treatments, and ratings of behavior following awakening were significantly impaired by both drug treatments. CONCLUSIONS: Pregabalin appears to have an effect on sleep and sleep architecture that distinguishes it from benzodiazepines. Enhancement of slow-wave sleep is intriguing, since reductions in slow-wave sleep have frequently been reported in fibromyalgia and general anxiety disorder.

Adolescent↗
PubMed2005

Suppression of the histamine-induced wheal and flare response by fexofenadine HCl 60 mg twice daily, loratadine 10 mg once daily and placebo in healthy Japanese volunteers.

BACKGROUND: The effects of the selective H1-receptor antagonist fexofenadine have been widely demonstrated in Western populations; however, to date, limited data comparing the effects of fexofenadine with other antihistamines have been reported in Japanese subjects. OBJECTIVE: To investigate the effect of fexofenadine and loratadine on the histamine-induced cutaneous wheal and flare response in healthy Japanese volunteers. METHODS: Eighteen healthy male and female Japanese volunteers aged 20-53 years were randomized to receive fexofenadine HCl 60 mg twice daily, loratadine 10 mg once daily or placebo in a 1-day, three-period, double-blind, crossover study. For each treatment, the wheal and flare response to 100 mg/mL histamine was assessed at baseline and at 1, 1.5, 2, 2.5, 3, 3.5, 4, 8, 12 and 24 hours post-dose. Blood samples were taken for pharmacokinetic analysis. RESULTS: Fexofenadine produced significantly greater percentage suppression of the overall wheal response compared with placebo and loratadine (43.1% versus 10.0% and 15.2%, respectively; p < 0.001). Similarly, fexofenadine significantly suppressed the overall flare response compared with placebo and loratadine (43.0% versus 3.5% and -8.9%, respectively; p < 0.01). Loratadine was statistically no different from placebo in terms of both overall wheal and flare suppression. Area under the curve analysis for wheal and flare reduction (0-12 hours post-dose) confirmed these findings. For wheal inhibition, fexofenadine had a significantly faster onset of action (defined as time to > or = 35% inhibition) compared with placebo (p < 0.001) and loratadine (p < 0.01); for flare, fexofenadine had a significantly faster onset of action than loratadine (p < 0.01). Mean maximum inhibition (the mean of the greatest inhibition achieved from baseline for each treatment) for wheal was achieved significantly faster with fexofenadine than loratadine (p < 0.01), and fexofenadine had a significantly longer duration of effect on suppressing wheal and flare compared with placebo and loratadine (p < 0.05 for all). The antihistamine effects of fexofenadine correlated significantly with its Cmax, while loratadine activity did not correlate significantly with its plasma levels. CONCLUSIONS: Fexofenadine is a potent suppressor of the histamine-induced wheal and flare response in healthy Japanese volunteers. These results support findings in Caucasian subjects, and confirm that fexofenadine has greater antihistaminergic activity than loratadine in this human model.

Adult↗
PubMed2005

Development of a portable psychometric testing device for use in the field: an alcohol investigation.

Cognitive and psychomotor performance have traditionally been assessed in the laboratory. There is a need for an objective portable assessment tool to assess cognitive and psychomotor performance. This study investigated the viability of a portable psychometric test battery, in a controlled laboratory environment, possibly leading to use in the field. A randomised, double-blind placebo controlled, three-way crossover design was employed. 16 subjects received 50 mg/100 ml and 80 mg/100 ml of alcohol and alcohol placebo. Performance was assessed with a tracking task, and an attention task presented on a small ruggedised handheld computer. The attention task showed no significant training effects; however, an element of the tracking task did. Statistical significance, effect size, and test-retest reliability analyses are presented indicating sensitivity of the portable psychometric test battery to the impairing effects of two separate doses of alcohol. Ability to undertake wide-scale impairment testing in the field with meaningful results in the absence of baseline data collection may have wide reaching implications, particularly in relation to the assessment of drivers impaired by drug use.

Adolescent↗
PubMed2005

Acute sleep responses in a normobaric hypoxic tent.

PURPOSE: Sleeping in a hypoxic environment is becoming increasingly popular among athletes attempting to simulate a "live high, train low" training regime. The purpose of this study was to investigate the acute effects (one night) of sleeping in a normobaric hypoxic tent (NH) (PO(2) = 110 mm Hg approximately 2500 m) upon markers of sleep physiology and quality, compared with sleep in a normal ambient environment (BL) (PO(2) = 159 mm Hg approximately sea level) and sleep in a normobaric normoxic tent (NN) (PO(2) = 159 mm Hg). METHODS: Eight male recreational athletes (age 34.5 +/- 6.9 yr; stature 169.1 +/- 8.7 cm; mass 69.3 +/- 8.2 kg; VO(2max) 56.4 +/- 8.3 mL.kg(-1).min(-1)) participated in the study using a randomized, double-blind crossover design. Polysomnographic studies were undertaken to measure sleep stages, arterial oxygen saturation (SpO(2)), heart rate (HR), and the Respiratory Disturbance Index (RDI). The Leeds Sleep Evaluation Questionnaire (LSEQ) was used to measure subjective sleep quality. RESULTS: NH (89.9 +/- 4.8%) resulted in a significantly lower (P < 0.05) SpO(2) compared with both BL (95.7 +/- 1.5%) and NN (93.5 +/- 4.0%). Heart rate was significantly higher (P < 0.05) in NH (51.5 +/- 7.6 beats.min(-1)) compared with NN (48.3 +/- 6.9 beats.min(-1)) but was similar versus BL (50.3 +/- 4.3 beats.min(-1)). RDI (counts.h) and RDI (total counts) were lowest in BL (3.5 +/- 2.5; 18.1 +/- 7.9) and highest in NH (36.8 +/- 42.7; 221.9 +/- 254.5). The difference in RDI (counts.h(-1) and total counts) between NH and BL was significant (P < 0.05). The LSEQ revealed that subjects' "behavior following waking" score was significantly (P < 0.05) lower in NH (40.9 +/- 9.2) compared with BL (52.3 +/- 8.3). CONCLUSION: This study presents evidence that sleep in a normobaric hypoxic tent at a simulated altitude of 2500 m may affect sleep parameters in some individuals. This type of analysis may be useful in the early identification of poorly responding individuals to simulated altitude environments.

Adult↗
PubMed2004

Effects of word frequency on recall memory following lorazepam, alcohol, and lorazepam alcohol interaction in healthy volunteers.

Free recall of words has been extensively used in psychopharmacology to assess the effects of CNS-active drugs on memory functions. However, there is a relative lack of information on the impact of word frequency on the subsequent recall of words following the administration of psychoactive drugs. The present double-blind, placebo-controlled, repeated-measures experiment used lorazepam and alcohol to test the effects of word frequency on immediate and delayed word recall in 24 healthy volunteers. One half of the words contained in the lists had a high frequency (HF) of occurrence and the remainder were of low frequency (LF). The results showed that LF words were more sensitive to memory impairment than HF words. However, the more accurate recall of HF words (with respect to LF words) was eliminated when a combination of lorazepam with alcohol was administered. These findings indicate that word frequency has a significant impact on memory and, as such, is a factor to be taken into account when using memory recall tasks to assess the effects of psychoactive drugs on memory.

Adolescent↗
PubMed2004

The effects of Ginkgo biloba extract (LI 1370) supplementation and discontinuation on activities of daily living and mood in free living older volunteers.

The aim of the study was to investigate the effects of continuing treatment with Ginkgo biloba extract (GBE) 120 mg/day on the activities of daily living (ADLs) and mood in healthy older volunteers who had immediately previously participated in a survey of the effects of a 4 month treatment with the drug. Following a prior postal survey investigating the effects of 4 months supplementation with GBE on ADLs and various aspects of mood and sleep, 1570 volunteers continued onto a 6 month follow-up postal survey. Subjects selected their own treatment option for the follow-up survey, which effectively created four groups: a continuation group who received GBE in the initial 4 month study and during the 6 month follow-up (GBE-GBE), a discontinuation group who received GBE in the initial study but not during the follow-up (GBE-NT), a new treatment group who did not receive GBE in the initial 4 month study but who did receive GBE during the 6 month follow-up (NT-GBE), and a no treatment group who received no treatment in either survey (NT-NT). At the end of the 6 month follow-up period each subject completed a line analogue rating scale (LARS) and a self-rating activities of daily living scale (SR-ADL). There were signi fi cant differences in the mean overall LARS and SR-ADL scores between the four treatment combination groups at the end of the follow-up period. A factor analysis of the LARS revealed two factors, 'mood' and 'alertness'. When scores from each of the treatment groups were examined over the whole 10 month period it was evident that the ratings of overall competence in the SR-ADL and both factors of the LARS were diminished on cessation of treatment with GBE, and improved when GBE treatment was initiated. The magnitude of the improvements on all scales was related to the overall duration of GBE supplementation.Signi fi cant differences between the groups of subjects treated with GBE for different periods of time (4-10 months) suggests that the extract has a demonstrable effect in improving mood and the self-assessed performance of the tasks of everyday living.

Activities of Daily Living↗
PubMed2004

A double-blind, randomized, 26-week study comparing the cognitive and psychomotor effects and efficacy of 75 mg (37.5 mg b.i.d.) venlafaxine and 75 mg (25 mg mane, 50 mg nocte) dothiepin in elderly patients with moderate major depression being treated in general practice.

To investigate the efficacy and cognitive and psychomotor effects of venlafaxine and dothiepin in elderly patients with moderate major depression. A prospective, randomized, double-blind, parallel-group, active comparator controlled study was conducted. Eighty-eight patients (aged > or = 60 years) were enrolled. Each patient received either venlafaxine (immediate release formulation) 37.5 mg twice per day or dothiepin 25 mg mane followed by 50 mg nocte for 26 weeks. Efficacy was assessed with the Montgomery-Asberg Depression Rating Scale and the Hamilton Depression Rating Scale. A psychometric test battery to assess cognitive function, activities of daily living and sleep consisted of Critical Flicker Fusion (CFF), Short-term Memory--Kim's Game, Cognitive Failures Questionnaire, Milford Epworth Sleepiness Scale, Leeds Sleep Evaluation Questionnaire, and an Accident Scoring Questionnaire. Quality of Life Questionnaires (Short Form 36 and Quality of Life in Depression Scale) were also administered. Venlafaxine significantly (p < 0.05) raised CFF scores compared to baseline but had no effect on any other measure. Dothiepin significantly (p < 0.05) lowered CFF threshold, and increased ratings of both sedation and difficulty in waking. The results showed that venlafaxine at doses of 37.5 mg b.i.d. in elderly depressed patients is free from disruptive effects on cognitive function and psychomotor performance.

Aged↗
PubMed2003

Comparative study of acute effects of single doses of fexofenadine, olopatadine, d-chlorpheniramine and placebo on psychomotor function in healthy volunteers.

Since most classical (first-generation) antihistamines have undesirable sedative effects on the central nervous system (CNS), newer (second-generation) antihistamines have been developed to relieve the sedative effects and to improve the patient's quality of life. However, the psychomotor profiles of second-generation antihistamines are not fully elucidated. In this randomized, double-blind, crossover study, the acute effects of single doses of second-generation antihistamines, fexofenadine (120 mg) and olopatadine (10 mg), on cognitive and psychomotor performance were investigated in comparison with those of placebo and d-chlorpheniramine (4 mg), a first-generation antihistamine, using objective and subjective assessments, in 11 healthy Japanese volunteers. In a battery of psychomotor tests, d-chlorpheniramine impaired tracking ability in the compensatory tracking task and caused a reduction in behavioural activity as continuously measured by wrist actigraphy. Olopatadine, like d-chlorpheniramine, reduced the behavioural activity, while fexofenadine had no effect in any of the tests. No significant changes in the subjects' self-ratings of drowsiness were found with the three antihistamines. These results suggest that d-chlorpheniramine and olopatadine, but not fexofenadine, produce sedative effects on psychomotor performance, and that the CNS profile of fexofenadine is different from that of olopatadine.

Adult↗
PubMed2003

A single-center, randomized, double-blind, placebo-controlled, crossover investigation of the effects of fexofenadine hydrochloride 180 mg alone and with alcohol, with hydroxyzine hydrochloride 50 mg as a positive internal control, on aspects of cognitive and psychomotor function related to driving a car.

BACKGROUND: Antihistamines (H(1)-receptor antagonists) are the mainstay of symptomatic therapy for allergic disorders. Antihistamines are needed that cause no disruptive effects on cognitive and psychomotor function. It is essential that antihistamines maintain the integrity of the cognitive system, not only in ambulatory patients at increased risk of drug-induced traffic- or work-related accidents, but also in students and others whose cognitive or intellectual impairment may adversely affect their performance.Objective; The goal of this study was to investigate the acute effects of fexofenadine hydrochloride 180 mg, alone and with a "social" dose of alcohol, on subjective feelings of sedation and on a battery of objective measures related to driving a car. These measures included information processing, psychomotor speed, and reaction time in an on-the-road car-driving task. Hydroxyzine hydrochloride 50 mg was included in the study as a positive internal control to validate the sensitivity of the psychometri tests to nonspecific impairment. METHODS: In this randomized, double-blind, 6-way, crossover study conducted at the Human Psychopharmacology Research Unit, Medical Research Centre (University of Surrey, Guildford, United Kingdom), 18 healthy volunteers received fexofenadine 180 mg, hydroxyzine 50 mg, and placebo alone and with alcohol (0.3 g/kg body weight or approximately 0.43-0.50 g/L blood-alcohol concentration). Treatment periods were separated by a washout period of at least 6 days. Subjects performed tests of cognitive and psychomotor performance at 1, 3, and 5 and hours after dosing. The test battery included subjective ratings of sedation, critical flicker fusion (CFF), choice reaction time (including recognition reaction time [RRT], motor reaction time [MRT], total reaction time [TRT], and brake reaction time [BRT]. RESULTS: Eighteen healthy male volunteers (median age, 30.5 years [range, 23-44 years]) were entered into the study. Fexofenadine alone and with alcohol had no significant effect on performance compared with placebo and was not distinguishable from placebo in any of the objective or subjective tests at any point. However, impairment was evident following the administration of hydroxyzine. Hydroxyzine caused significant impairment in CFF (P < 0.05), RRT (P < 0.001), and TRT (P < 0.001) compared with placebo. Hydroxyzine with alcohol significantly disrupted performance on all of the above measures with respect to both placebo and fexofenadine (P < 0.05) as well as MRT (P < 0.001). No significant treatment effects on BRT were found. CONCLUSION: Fexofenadine 180 mg did not have disruptive effects on objective measures related to driving a car and aspects of psychomotor and cognitive function, even when combined with a dose of alcohol equivalent to 0.3 g/kg body weight, in a study in which the psychometric assessments were shown to be sensitive to impairment.

Adult↗
PubMed2003

The effects of acute doses of fexofenadine, promethazine, and placebo on cognitive and psychomotor function in healthy Japanese volunteers.

BACKGROUND: Genetic variations in cross-cultural metabolic capability may attenuate the lack of central nervous system effects of fexofenadine. OBJECTIVE: To compare the pharmacodynamics of fexofenadine and promethazine versus placebo in Japanese volunteers. METHODS: In this randomized, crossover, double-blind study, 24 subjects received single doses of fexofenadine 60 mg and 120 mg, promethazine 25 mg, and placebo, with a 6-day washout period between treatments. Objective measures included critical flicker fusion, choice reaction time, and a compensatory tracking task. A line analog rating scale evaluated self-rated sedation. A rapid visual information-processing task evaluated vigilance at baseline and at 2 hours. RESULTS: Fexofenadine was not significantly different from placebo on any test at any timepoint. In contrast, promethazine impaired critical flicker fusion thresholds (F[3,63] = 5.37, P = 0.0023); increased recognition reaction time (F[3,63] = 13.63, P < 0.0001) and total reaction time (F[3,63] = 12.23, P < 0.0001) components of the choice reaction time test; reduced tracking accuracy (F[3,63] = 14.25, P < 0.0001) and increased reaction times to peripheral stimuli (F[3,63] = 9.29, P < 0.0001) in the compensatory tracking task; reduced the number of valid responses (F[3,63] = 14.86, P < 0.0001) and impaired reaction times (F[3,63] = 12.02, P < 0.0001) in the rapid visual information-processing task test; and impaired subjective ratings of sedation (F[3,63] = 7.55, P = 0.0002), compared with placebo. CONCLUSIONS: A battery of tests sensitive to impairment by promethazine failed to show any negative cognitive or psychomotor effects with fexofenadine 60 and 120 mg. Fexofenadine is an intrinsically non-impairing antihistamine in Japanese subjects.

Adult↗