Eveli Truksinas

Continuous positive airway pressure therapy improves hypoadiponectinemia in severe obese men with obstructive sleep apnea without changes in insulin resistance.

BACKGROUND Obstructive sleep apnea (OSA) is associated with several conditions that could facilitate the onset of cardiovascular and metabolic dysfunctions. Continuous positive airway pressure (CPAP) therapy has been shown to improve cardiovascular morbidity and mortality related to OSA, but the mechanisms underlying this association are not fully understood. OBJECTIVE The aim of the present study was to evaluate whether sleep apnea contributes to insulin resistance and inflammatory marker alterations and to evaluate the benefits of nasal CPAP therapy in severe obese patients with OSA. METHODS Plasma inflammatory cytokines and the homeostasis model assessment of insulin resistance index (HOMA-IR, Insulin Sensitivity Index [ISI]) were measured in severe obese male with OSA (n = 16) and compared with body mass index (BMI)-matched male controls without OSA (n = 13). Seven patients with severe sleep apnea (apnea-hypopnea index >30 events/h) were reevaluated after 3 months of nasal CPAP therapy. RESULTS OSA patients had a significantly lower adiponectin levels than obese controls (8.7 +/- 1.18 ng/mL vs. 15.0 +/- 2.55 ng/mL, P = 0.025). HOMA-IR, ISI, tumor necrosis factor-alpha (TNF-alpha, C-reactive protein (CRP), and interleukin-6 (IL-6) levels were not different between groups. Although insulin resistance index and BMI values did not change after 3 months of nCPAP therapy, adiponectin levels increased (P = 0.036) and the levels of TNF-alpha tended to decrease (P = 0.065). Changes in adiponectin levels during nCPAP therapy were positively correlated with an improvement in minimum oxygen saturation (r = 0.773; P = 0.041) and negatively correlated with changes in TNF-alpha levels (r = -0.885; P = 0.008). CONCLUSIONS nCPAP therapy reverses hypoadiponectinemia levels present in obese men with OSA, probably through reductions in hypoxia and inflammation activity.

Sleep perception in insomniacs, sleep-disordered breathing patients, and healthy volunteers – An important biologic parameter of sleep

BACKGROUND The mechanisms involved in sleep perception are not widely known. Therefore, we believe that investigating this phenomenon is the best way to understand some of the mechanisms involved in several sleep disturbances, particularly insomnias. OBJECTIVE The objective of our study was to evaluate sleep perception in insomniacs, sleep-disordered breathing (SDB) patients, and healthy volunteers. Our hypothesis was that insomniacs have less sleep perception than healthy individuals and patients with sleep respiratory disorders. METHODS We studied 199 individuals who were divided into the following four groups: (1) insomnia group; (2) patients with sleep-disordered breathing; (3) patients with insomnia complaints and an associated sleep respiratory disorder; and (4) healthy individuals with no sleep complaints. All patients were subjected to polysomnography (PSG) followed by a questionnaire addressing their perception about the previous nights sleep. In addition to analysis of all sleep parameters, we determined sleep perception as the percentage of the ratio between total sleep time perceived by the patient and the total sleep time obtained by PSG. RESULTS Sleep perception was significantly lower in insomnia patients than in sleep-disordered breathing patients or the normal group. In addition, no significant differences across the four groups were observed in sleep efficiency and total sleep time. CONCLUSIONS The results showed that the reported sleep perception of insomniacs is lower than that of sleep-disordered breathing patients or normal individuals. We believe that sleep perception is as important as other commonly measured parameters, such as sleep efficiency.

Polysomnography findings in spinocerebellar ataxia type 6.

Spinocerebellar ataxia type 6 (SCA6) is usually described as a pure ataxia syndrome. However, SCA6 patients may have sleep complaints. In this paper, sleep disorders were investigated in patients with SCA6. Twelve SCA6 patients and 12 subjects matched by gender, age and body mass index (control group) underwent polysomnography and clinical investigation for sleep disorders. SCA6 had a higher frequency of snoring (P = 0.01), a higher index of awakening due to respiratory events (P = 0.003) and central apnea events during sleep (P = 0.024), a longer sleep Stage N1 (P = 0.02) and a lower sleep Stage N3 (P = 0.05) in SCA6 patients than in control subjects. SCA6 patients had a reduction in slow wave sleep and a higher frequency of snoring and respiratory disorders during sleep when compared to the control group.

Can we improve stroke rehabilitation after a circadian preference study

Individual circadian preferences represent the rhythmic expression of biological and behavioral patterns, such as the sleep– wake cycle (1). Several physiological parameters follow this intrinsic tendency. For instance, increased body temperature near the circadian acrophase is associated with improvement in motor and cognitive performances (2). In stroke patients, the possible trend of behavioral and motor-disability oscillations during daytime has been less studied. Data indicate that morningpreferring patients with cognitive impairments performed the worst when tested in the evening (nonpreferred time) during rehabilitation (3). Motor performance also exhibits a circadian pattern. Among inpatients in rehabilitation with neuromuscular disorders, longer durations of motor activity such as writing and walking were observed at 8 am, 11 am, and 11 pm (4). These findings suggest a possible influence of the circadian clock on cognitive performance and physical exercises during rehabilitation. Although the role of the circadian pattern in the onset of stroke is already well established (5), studies investigating the effectiveness of performing rehabilitation sessions during the preferred circadian time of patients after stroke are still warranted. We believe that individual circadian features could affect the motor and cognitive performances of stroke patients, influencing the time of recovery during rehabilitation. We strongly recommend that rehabilitation sessions should occur during the preferred period of stroke patients. Unfortunately, this is not always possible. Indeed, our public rehabilitation system is overloaded, and patient’s followup depends on the center’s availability. Thus, further investments and studies must be done to clarify the relationship between circadian preference and rehabilitation status in stroke patients. A rehabilitation schedule following circadian preferences may improve the stroke patient’s recovery, which could decrease treatment duration and lead to greater cost-effectiveness in the rehabilitation system.