Chronotype and circadian rhythm in bipolar disorder: A systematic review.

Despite a complex relationship between mood, sleep and rhythm, the impact of circadian disruptions on bipolar disorder (BD) has not been clarified. The purpose of this systematic review was to define current evidence regarding chronotype and circadian rhythm patterns in BD patients. 42 studies were included, involving 3432 BD patients. Disruption of the biological rhythm was identified, even in drug-naïve BD patients and independently of mood status. Daily profiles of melatonin levels and cortisol indicated a delayed phase. Depression was more frequently associated with circadian alterations than euthymia. Few studies evaluated mania, demonstrating irregular rhythms. Evening type was more common in BD adults. Studies about the influence of chronotype on depressive symptoms showed conflicting results. Only one investigation observed the influences of chronotype in mania, revealing no significant association. Effects of psychoeducation and lithium on rhythm in BD patients were poorly studied, demonstrating no improvement of rhythm parameters. Studies about genetics are incipient. In conclusion, disruption in circadian rhythm and eveningness are common in BD. Prospective research evaluating the impact of circadian disruption on mood symptoms, metabolism, seasonality, the influence of age and the effects of mood stabilizers are needed.

Actigraphic assessment of sleep in chronic obstructive pulmonary disease.

PURPOSE: Previously, sleep in chronic obstructive pulmonary disease (COPD) has been objectively investigated only by lab-based polysomnography. The main purpose of this study was to evaluate sleep quality in COPD patients in their home environment using actigraphy. We also investigated the factors associated with sleep impairment and the relationship between objective and subjective sleep quality and daytime somnolence in these patients. METHODS: Twenty-six patients with moderate to very severe COPD and 15 controls were studied by actigraphy for at least 5 days. Subjective sleep quality was evaluated by the Pittsburgh Sleep Quality Index and daytime sleepiness by the Epworth Sleepiness Scale (ESS). Dyspnea was quantified by the modified Medical Research Council (MMRC) scale. RESULTS: COPD patients showed increased sleep latency (p = 0.003), mean activity (p = 0.003), and wake after sleep onset (p = 0.003) and reduced total sleep time (TST; p = 0.024) and sleep efficiency (p = 0.001), as compared to controls. In patients, severity of dyspnea was correlated with sleep activity (r = 0.41; p = 0.04) and TST (r = -0.46; p = 0.02) and multiple regression analysis showed that MMRC score was the best predictor of TST (p = 0.02) and sleep efficiency (p = 0.03). Actigraphy measures during daytime were not significantly different between patients and controls. Subjective sleep quality was poorer in patients than controls (p = 0.043). ESS scores were not significantly different between the two groups. Actigraphy measures were not correlated with subjective sleep quality or daytime somnolence in both groups. CONCLUSIONS: Nocturnal sleep is markedly impaired in stable COPD patients studied by actigraphy in their home environment and this impairment is related to severity of dyspnea.

Hyponatremia, acute kidney injury, and mortality in HIV-related toxoplasmic encephalitis.

BACKGROUND: There are no reports on hyponatremia and acute kidney injury (AKI) involved in the course of HIV-related toxoplasmic encephalitis (TE). The main objective of this study was to describe the occurrence of hyponatremia and its relationship with AKI and mortality in HIV-related toxoplasmic encephalitis (TE). METHODS: This was a retrospective cohort study on patients with HIV-related TE. AKI was considered only when the RIFLE (risk, injury, failure, loss, end-stage) criterion was met, after the patient was admitted. RESULTS: A total of 92 patients were included, with a mean age of 36±9 years. Hyponatremia at admission was observed in 43 patients (46.7%), with AKI developing in 25 (27.1%) patients during their hospitalization. Sulfadiazine was the treatment of choice in 81% of the cases. Death occurred in 13 cases (14.1%). Low serum sodium level correlated directly with AKI and mortality. Male gender (OR 7.89, 95% CI 1.22-50.90, p = 0.03) and hyponatremia at admission (OR 4.73, 95% CI 1.22-18.30, p = 0.02) were predictors for AKI. Independent risk factors for death were AKI (OR 8.3, 95% CI 1.4-48.2, p < 0.0001) and hyponatremia (OR 9.9, 95% CI 1.2-96.3, p < 0.0001). CONCLUSION: AKI and hyponatremia are frequent in TE. Hyponatremia on admission is highly associated with AKI and mortality.

Risk factors for depressive symptoms in a large population on chronic hemodialysis.

Despite their significant influence on the quality of life, depressive symptoms are not usually included as a clinical parameter in the evaluation of hemodialysis patients. We aimed to identify depressive symptoms and associated risk factors in a large group of individuals with end-stage renal disease (ESRD) on chronic hemodialysis. This was a cross-sectional study of 400 consecutive patients. Cases were analyzed according to the presence/absence of depressive symptoms. All individuals were investigated by interview, and all variables were measured concurrently. Depressive symptoms were evaluated by the Beck Depression Inventory (BDI-II ≥16) and sleep quality by the Pittsburgh Sleep Quality Index (PSQI > 5). Among the 400 patients (59% male), depressive symptoms were present in 77 (19.3%). Depressive symptoms were more common in women and were independently associated with poor sleep quality (P = <0.005), unemployment (P = 0.001), diabetes (P = 0.02), hypoalbuminemia (P = 0.01), low education (P = 0.03), and pruritus (P = 0.04). Women with ESRD on chronic hemodialysis are at increased risk of depression. Furthermore, unemployment and the presence of diabetes, hypoalbuminemia, low education, and pruritus are significantly associated with depressive symptoms. Depressive symptoms are also independently associated with poor quality sleep and studies about the effects of sleep hygiene therapy on depressive symptoms are warranted.

Sleep disturbances and brain MRI morphometry in Parkinson's disease, multiple system atrophy and progressive supranuclear palsy - a comparative study.

Despite common reports in Parkinson's disease (PD), in other parkinsonian syndromes, sleep disturbances have been less frequently described. This study evaluated and compared sleep disturbances in patients with PD, multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) and analyzed associations with brain magnetic resonance imaging (MRI) morphometry. This was a cross-sectional study of 16 PD cases, 13 MSA, 14 PSP and 12 control. Sleep disturbances were evaluated by Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index (PSQI), Restless Legs Scale and Berlin questionnaire. Pons area, midbrain area, medial cerebellar peduncle (MCP) width, and superior cerebellar peduncle width were measured using MRI. Poor quality sleep, risk of obstructive sleep apnea (OSA) and restless legs syndrome (RLS) were detected in all groups. Patients with MSA showed higher risk of OSA and less frequent RLS. In MSA, a correlation between PSQI scores and Hoehn and Yahr stage was observed (p<0.05). In PSP, RLS was frequent (57%) and related with reduced sleep duration and efficiency. In PD, excessive daytime sleepiness was related to atrophy of the MCP (p=0.01). RLS was more frequent in PD and PSP, and in PSP, was associated with reduced sleep efficiency and sleep duration. Brain morphometry abnormalities were found in connection with excessive daytime sleepiness and risk of OSA in PD and PSP suggesting widespread degeneration of brainstem sleep structures on the basis of sleep abnormalities in these patients.

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.

Restless legs syndrome and quality of sleep in type 2 diabetes.

OBJECTIVE: To investigate the presence of restless legs syndrome (RLS) and the quality of sleep in a population of type 2 diabetic patients. RESEARCH DESIGN AND METHODS: The study population was composed of 100 consecutive patients regularly attending a diabetes clinic at the University Hospital of the Federal University of Ceará. The subjects' quality of sleep was assessed by the Pittsburgh Sleep Quality Index, and excessive daytime sleepiness (EDS) was measured by the Epworth Sleepiness Scale. The RLS was diagnosed using the four minimum criteria defined by the International Restless Legs Syndrome Study Group. Other relevant clinical and laboratory parameters were obtained by interview and chart review. RESULTS: RLS was found in 27% of patients. Poor sleep quality was present in 45% of cases and was associated with age (P = 0.04), peripheral neuropathy (P = 0.001), and RLS (P = 0.000). EDS was found in 26% of patients. Logistic regression analysis revealed an association between RLS and peripheral neuropathy (odds ratio 12.85 [95% CI 2.83-58.40], P = 0.001). CONCLUSIONS: RLS is common in type 2 diabetic patients and can be a major cause of sleep disruption in these patients.

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.

Melatonin improves sleep in asthma: a randomized, double-blind, placebo-controlled study.

Disturbed sleep is common in asthma. Melatonin has sleep-inducing activity and reportedly affects smooth muscle tone and inflammation. The aim of this study was to evaluate the effect of melatonin on sleep in patients with mild and moderate asthma. This was a randomized, double-blind, placebo-controlled study. Twenty-two consecutive women with asthma were randomized to receive melatonin 3 mg (n = 12) or placebo (n = 10) for 4 weeks. Sleep quality and daytime somnolence were assessed by the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale, respectively. Pulmonary function was assessed by spirometry. Use of relief medication, asthma symptoms, and morning and evening peak expiratory flow rate were recorded daily. Melatonin treatment significantly improved subjective sleep quality, as compared with placebo (p = 0.04). No significant difference in asthma symptoms, use of relief medication and daily peak expiratory flow rate was found between groups. We conclude that melatonin can improve sleep in patients with asthma. Further studies looking into long-term effects of melatonin on airway inflammation and bronchial hyperresponsiveness are needed before melatonin can be recommended in patients with asthma.

Snoring and excessive daytime sleepiness in Parkinson's disease.

Recent recognition of daytime sleepiness in Parkinson's 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 Parkinson's 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).

Event related P300 potential in NIDDM patients without cognitive impairment and its relationship with previous hypoglycemic episodes.

OBJECTIVES: The purpose of this study was to evaluate the ERP P300 in non insulin dependent diabetes mellitus (NIDDM) patients without cognitive impairment and the relationship with clinical variables, the presence of retinopathy and previous hypoglycemic episodes. METHODS: NIDDM patients (N=44) without evidence of cognitive impairment and controls (N=17) were studied clinically and with ancillary exams and the ERPs P300 were recorded. Patients were examined clinically and with the Folstein Mini-Mental Examination (MMSE) for cognitive function and all patients showed a score higher than 26 (maximal value=30). Previous hypoglycemia was evaluated through a questionnaire establishing the number of episodes and the symptoms of hypoglycemia in a scale scoring from zero to 15. RESULTS: ERP P300 latencies were significantly higher in NIDDM patients than in controls (p<0.03). ERP P300 measures were significantly related to age (Pearson, p<0.01) and not to metabolic variables, disease duration or the presence of retinopathy. Severity of hypoglycemia was not associated to ERP P300 latency. CONCLUSIONS: Our study supports the evidence that NIDDM patients, without signs of nervous system involvement, have ERP P300 alterations and this is not related to retinopathy, metabolic variables or previous hypoglycemic episodes. Chronic hyperglycemia may alter brain glucose transport and increase tolerance to hypoglycemia effects in the nervous system.

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.