Veralice Meireles Sales de Bruin

Effect of exogenous melatonin on sleep and motor dysfunction in Parkinson's disease. A randomized, double blind, placebo-controlled study.

Insomnia, sleep fragmentation and excessive daytime sleepiness are common in Parkinsons disease (PD) and may contribute to the reduction of cognition and alertness in those patients. Melatonin has been shown to improve sleep in several conditions. In experimental models of PD, melatonin can ameliorate motor symptoms. To evaluate the effect of melatonin on sleep and motor dysfuntion in PD, we studied 18 patients (Hoehn & Yahr I to III) from a PD clinic. Prior to treatment, motor dysfunction was assessed by UPDRS II, III and IV. Subjective sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI) and daytime somnolence by the Epworth Sleepiness Scale (ESS). Full polysomnography (PSG) was performed in all subjects. Patients were then randomized to receive melatonin (3mg) or placebo one hour before bedtime for four weeks. All measures were repeated at the end of treatment. On initial assessment, 14 patients (70%) showed poor quality sleep (PSQI > 6) and eight (40%) excessive daytime sleepiness (ESS > 10). Increased sleep latency (50%), REM sleep without atonia (66%), and reduced sleep efficiency (72%) were found on PSG. Eight patients had an apnea/ hipopnea index greater than 15 but no severe oxygen desaturation was observed. Sleep fragmentation tended to be more severe in patients on lower doses of levodopa (p = 0.07). Although melatonin significantly improved subjective quality of sleep (p = 0.03) as evaluated by the PSQI index, PSG abnormalities were not changed. Motor dysfunction was not improved by the use of melatonin. Undetected differences in motor scores and PSG findings may have been due to a small sample size and a type II error.

Snoring and excessive daytime sleepiness in Parkinson's disease.

Recent recognition of daytime sleepiness in Parkinsons disease (PD) has prompted a search for its causes. Sleepy patients may be more susceptible to sleep attacks after the use of dopamine agonists and the recognition of sleep disturbances in PD may influence important therapeutic decisions. To identify clinical factors influencing excessive daytime sleepiness (EDS) and sleep complaints in PD, we studied 86 consecutive patients with clinical diagnosis of PD using a sleep questionnaire, the Epworth Sleepiness Scale, the Unified Parkinsons Disease Rating Scale and the Montgomery and Asberg Depression Rating Scale. Patients with cognitive dysfunction were not included in the study. We found that 49 patients (53.3%) had insomnia, 45 (49.9%) restless legs syndrome (RLS), 51 (55.4%) vivid dreams, 61 (71.8%) snoring and 29 (31.5%) had EDS. RLS was more frequent in patients with longer duration of illness. Snoring was the most important risk factor associated with EDS (OR=3.64, 95% CI=1.11-11.9, P=0.03) and a marginal association between motor dysfunction and EDS was observed (OR=1.06, 95% CI=1.00-1.12, P=0.05).

Swallowing abnormalities and dyskinesia in Parkinson's disease

Gastrointestinal abnormalities in Parkinsons disease (PD) have been known for almost two centuries, but many aspects concerning their pathophysiology have not been completely clarified. The aim of this study was to characterize the oropharyngeal dynamics in PD patients with and without levodopa‐induced dyskinesia. Fifteen dyskinetic, 12 nondyskinetic patients, and a control group were included. Patients were asked about dysphagia and evaluated with the Unified Parkinsons Disease Rating Scale Parts II and III and the Hoehn and Yahr scale. Deglutition was assessed using modified barium swallow with videofluoroscopy. Nondyskinetic patients, but not the dyskinetic ones, showed less oropharyngeal swallowing efficiency (OPSE) for liquid food than controls (Dunnett, P = 0.02). Dyskinetic patients tended to have a greater OPSE than nondyskinetic (Dunnett, P = 0.06). Patients who were using a higher dose of levodopa had a greater OPSE and a trend toward a smaller oral transit time (Pearsons correlation, P = 0.01 and 0.08, respectively). Neither the report of dysphagia nor any of the PD severity parameters correlated to the videofluoroscopic variables. In the current study, dyskinetic patients performed better in swallowing function, which could be explained on the basis of a greater levodopa dose. Our results suggest a role for levodopa in the oral phase of deglutition and confirm that dysphagia is not a good predictor of deglutition alterations in PD.

Restless legs syndrome in end-stage renal disease: Clinical characteristics and associated comorbidities

BACKGROUND Despite being frequently described in patients with end-stage renal disease (ESRD), clinical characteristics and comorbidities in association with restless legs syndrome (RLS) are still to be confirmed. OBJECTIVES The aim of this study was to investigate clinical factors associated with RLS in ESRD patients in hemodialysis. METHODS This is a cross-sectional study of 400 patients on hemodialysis, evaluating RLS, clinical features and other sleep abnormalities. RESULTS Out of 400, 86 patients presented RLS (21.5%; mean age 48.8+/-13.8y), being more frequent in females (p<0.005). Forty-eight individuals (12% mean age 50.7+/-13.1y) had moderate/severe RLS, 14 reported symptoms prior to hemodialysis, 13 described family history of RLS, and eight described symptoms as disturbing during dialysis. RLS cases showed lower hemoglobin (p<0.005), poorer quality of sleep (Pittsburgh Sleep Quality Index >5, p=0.002), higher scores on the Beck Depression Inventory Scale (p<0.005), greater scores on the Charlson Comorbidity Index (p=0.01) and the Epworth Sleepiness Scale (p=0.001) and higher risk of obstructive sleep apnea (OSA; Berlin questionnaire, p=0.01). Hypertension was more frequent in cases with moderate/severe RLS (p=0.01) and remained after controlling for the risk of OSA (p=0.02). CONCLUSION In ESRD patients in hemodialysis, RLS is present in 21.5%; 16% report symptoms prior to hemodialysis and a family history of RLS. Symptoms are disturbing during hemodialysis in 9% of cases. RLS is associated with lower hemoglobin, worse sleep quality, excessive daytime sleepiness, depressive symptoms and higher risk of OSA. Hypertension is associated with moderate/severe RLS.

HYPERSOMNOLENCE AND ACCIDENTS IN TRUCK DRIVERS: A CROSS-SECTIONAL STUDY

Truck drivers are more likely to suffer severe injury and death due to certain truck driving characteristics. Identifying and preventing factors associated with accidents in this population is important to minimize damage and improve road safety. Excessive daytime sleepiness is a major public health problem, leading to impaired cognitive function, reduced alertness, and increased risk of motor vehicle crashes. The aim of this cross‐sectional study was to determine the prevalence and predictors of hypersomnolence (defined as an Epworth Sleepiness Scale score greater than 10) among truck drivers. Three hundred male truck drivers were studied. Quality of sleep was assessed by the Pittsburgh Sleep Quality Index, and the association between demographic, clinical, and occupational data with excessive sleepiness was analyzed. The mean daily sleep duration was 5.6±1.3 h, and poor quality of sleep was found in 46.3% of the individuals. Hypersomnolence was found in 46% of the drivers and was associated with younger age, snoring, and working >10 h without rest. A positive correlation between hypersomnolence and previous accidents was detected (p=0.005). These results show that sleep deprivation and hypersomnolence are frequent among truck drivers. The treatment of sleep‐disordered breathing and the implementation of educational programs, particularly targeting younger drivers and promoting increased awareness of the deleterious effects of sleep loss and work overload, may help to reduce hypersomnolence and accidents among truck drivers.

Depression in Medical School: The Influence of Morningness‐Eveningness

Medical students are at higher risk for depression, affecting not only their lives but also patient care. This article studied a population of medical students engaged in lecture‐based learning regarding the presence of depressive symptoms and its relation to morningness‐eveningness. Depressive symptoms were assessed by the Beck Depressive Inventory scale (BDI>10), and diurnal preference was assessed by the Horne & Östberg Morningness/Eveningness Questionnaire (MEQ). Family history of depression and involvement in regular physical activity were also investigated. A total of 161 students, 77 (47.8%) males, aged 19 to 30 yrs (22.1±2.1) living in a city close to the equator were evaluated. Fifty‐three individuals (32.9%) had depressive symptoms. Depressive individuals showed a trend to be female (p=0.07). Also, female gender showed a non‐significant shift toward morningness. Fifty‐eight (36.0%) subjects participated in regular physical activity. In 57 cases (35.4%), there was a history of depression in the family. Fifteen individuals (9.3%) were definitely evening type, 42 (26.1%) were moderately evening type, 44 (27.3%) were indifferent, 42 (26.1%) were moderately morning type, and 18 (11.2%) were definitely morning type. Family history of depression (OR=0.29, 95% CI=1.37–6.12) and sedentary life (OR=0.28, 95% CI=0.12–0.65) were associated with depressive symptoms. Eveningness was associated with depressive symptoms (OR=0.66, 95% CI=0.50–0.88), and this association remained significant after adjusting for the presence of familial depression and physical activity (OR=0.71, 95% CI=0.52–0.95). In conclusion, depressive symptoms are independently associated with “eveningness” in medical students. These results should be confirmed by future studies involving a larger number of subjects.

Attenuating effects of melatonin on pilocarpine-induced seizures in rats.

Daily melatonin (10-50 mg/kg, i.p.) treatment at 08.30 h or 17.00 h for 1 week of female rats (2-months-old) increased the latency to the appearance of the first convulsion in the pilocarpine-induced seizure model. Other behavior parameters remained unaltered. The anticonvulsant effect of melatonin seemed to be more intense at the light-dark transition. Moreover, the effect of repeated melatonin treatment was also age-related, since it showed a lower threshold in 2-month-old than in 21-day-old rats, and the acute treatment was not efficient. [3H]N-methylscopolamine binding was unaltered in the hippocampus and striatum of adult rats after the association of melatonin and pilocarpine. While muscarinic binding was unaltered in adult rats, it increased in the hippocampus of young rats in the presence of melatonin (50 mg/kg) and pilocarpine, and did not change in the striatum. Melatonin partially recovered [3H]GABA binding in the hippocampus in the presence of pilocarpine-induced seizures, and intensified pilocarpine effects in the striatum of adult rats.

Risk factors for depression in truck drivers

OBJECTIVE Depression is a major public health problem. Work stress is associated with depression and workers whose jobs impose high levels of psychological demands, such as truck drivers, may be at increased risk. The aim of this study was to investigate the prevalence and correlates of depression in truck drivers. METHOD This was a cross-sectional study of 300 male truck drivers. Presence and severity of depression were assessed by the Mini International Neuropsychiatric Interview followed by the Beck Depression Inventory Short Form. Relevant demographic, clinical and occupational data were collected using a purpose-built questionnaire. RESULTS The prevalence of depression among truck drivers was 13.6%. Multivariate analysis showed that being 45 years or older had a protective effect (OR=0.19; P=0.02), whereas low educational level (OR=3.03; P=0.01), use of stimulants (OR=5.03; P<0.01) and wage-earning (OR=2.84; P=0.01), as opposed to self-employment, increased the risk for depression. CONCLUSIONS Truck drivers are at increased risk for depression when compared to the general population. Efforts to increase awareness of this problem and to limit the use of stimulants, as well as measures to improve job satisfaction, particularly among the wage-earning drivers, may have a positive impact on mental health in these workers.

Sleep disturbances in patients on maintenance hemodialysis: role of dialysis shift

OBJECTIVES Subjective sleep complaints have been reported in up to 80% of patients with end stage renal disease (ESRD). In these patients, sleep disturbances manifesting as insomnia, sleep apnea syndrome, restless leg syndrome (RLS), periodic limb movement disorder and excessive daytime sleepiness (EDS) have been frequently reported. Moreover, studies about the role of dialysis shift on sleep abnormalities, morbidity and mortality are still scarce. The aim of this study was to investigate the influence of dialysis shift on the quality of sleep and sleep abnormalities in patients with ESRD. METHODS We studied one hundred consecutive patients from a dialysis center. Quality of sleep was assessed by the Pittsburgh Sleep Quality Index and subjective EDS by the Epworth Sleepiness Scale. Restless leg syndrome was diagnosed using the four minimum criteria defined by the International Restless Legs Syndrome Study Group. Clinical and laboratory parameters were obtained by interview and chart review. Adequacy of dialysis was evaluated by the Kt/V index. RESULTS Poor quality sleep (PSQI>6) was found in 75% of cases and was associated with RLS (p=0.004) and with snoring (p=0.016). EDS (ESS>10) was present in 28% of cases. Patients with EDS (1.33+/-0.29) had lower values of the Kt/v index (P=0.01) than those without EDS (1.52+/-0.32). RLS was present in 48% of cases. Irrespective of dialysis shift, poor quality sleep, EDS and RLS were not different among patients. CONCLUSION Poor quality sleep, EDS and RLS were common and not related to dialysis shift.

The effect of venlafaxine on behaviour, body weight and striatal monoamine levels on sleep-deprived female rats

Partial sleep deprivation is clinically associated with fatigue, depressive symptoms and reduced memory. Previously, it has been demonstrated that venlafaxine, an atypical antidepressant, increases the levels of noradrenaline and serotonin in rat hippocampus. The aim of this study was to evaluate the effects of venlafaxine on depression, anxiety, locomotor activity and memory in a model of REM sleep (REMs) deprivation in rats. We have also studied the influence of venlafaxine on monoamine levels in the striatum. Six groups of animals (N=20 each) were treated with saline or venlafaxine (1 or 10 mg/kg) during 10 days, submitted or not to REMs deprivation and studied with the forced swimming test of Porsolt (STP), plus-maze, passive avoidance and open-field tests right after sleep deprivation. Animals were also studied for passive avoidance 24 h later (rebound period). Brain samples for monoamine measurements were collected either immediately after REMs deprivation or after 24 h. Both REMs deprivation and venlafaxine showed an antidepressant effect. An anxiolytic effect was also observed after REMs deprivation. Previous treatment with venlafaxine blocked the antidepressant and anxiolytic effects of REMs deprivation. REMs deprivation alone and treatment with venlafaxine 10 mg/kg increased locomotor activity, and this effect was inhibited by venlafaxine in REMs deprived rats. Both venlafaxine treatment and REMs deprivation induced weight loss. Venlafaxine treatment, but not REMs deprivation, induced an increase in striatal dopamine (DA) levels. The combination of REMs deprivation and venlafaxine treatment was associated with an increase in serotonin turnover 24 h after rebound sleep. In this study, venlafaxine treatment hindered most behavioral effects of REMs deprivation and was associated with an interference on dopamine and serotonin systems in the striatum.