Search PubMed⌕ Search

Biomedical subjects

A Vela-Bueno

Publications and source records attributed to A Vela-Bueno.

At least 19 recordsLinked to original sources
PubMed2005

Excessive daytime sleepiness in a general population sample: the role of sleep apnea, age, obesity, diabetes, and depression.

CONTEXT: Excessive daytime sleepiness (EDS) is commonly considered a cardinal sign of sleep apnea; however, the mechanism underlying the association is unclear. OBJECTIVE: The purpose of this study was to assess the association between the complaint of EDS and sleep apnea, considering a wide range of possible risk factors in a population sample. DESIGN AND SETTING: We examined this question in the Penn State cohort (a random sample of 16,583 men and women from central Pennsylvania, ranging in age from 20 to 100 yr). A random subset of this cohort (n = 1,741) was further evaluated for one night in the sleep laboratory. MAIN OUTCOME MEASURE: The main measure was a complaint of EDS. RESULTS: The final logistic regression model indicated depression was the most significant risk factor for EDS followed by body mass index, age, typical sleep duration, diabetes, smoking, and finally sleep apnea. The strength of the association with EDS decreased with increasing age, whereas the association of depression with EDS was stronger in the young. EDS is more prevalent in the young (<30 yr), suggesting the presence of unmet sleep needs and depression, and in the very old (>75 yr), suggesting increasing medical illness and health problems. EDS was associated with a reduced report of typical sleep duration without any association with objective polysomnographic measures. CONCLUSIONS: It appears that the presence of EDS is more strongly associated with depression and metabolic factors than with sleep-disordered breathing or sleep disruption per se. Our findings suggest that patients with a complaint of EDS should be thoroughly assessed for depression and obesity/diabetes independent of whether sleep-disordered breathing is present.

Adult↗
PubMed2002

Insomnia in central Pennsylvania.

OBJECTIVE: Establish the association between insomnia and various physical and mental health symptoms as well as objective measures of sleep disturbance while controlling for age, gender and BMI in a large random sample of the general public. METHODS: A subsample (N=1741) was selected for a single-night sleep laboratory evaluation from a larger random sample (N=16,583) of the general public (20-100 years old). RESULTS: The prevalence of insomnia was 7.5% and difficulty sleeping an additional 22.4%. The complaints were more frequent in women and in non-Caucasian minorities. A multivariate logistic regression analysis indicated that depression was the single strongest factor followed by female gender associated with either insomnia or difficulty sleeping. Minority status and a history of colitis, hypertension and anemia were also associated, but to a lesser degree. The final model did not include age, BMI as well as any of the sleep laboratory findings. CONCLUSION: These findings support the conclusion that mental health variables have the primary independent association with a complaint of insomnia. Other factors including minorities and hypertension are also independently associated, though to a lesser degree. Other primary sleep disorders, e.g., sleep apnea, do not seem to play a major role in insomnia. These findings underscore the fact that insomnia is a symptom associated with a wide variety of mental and physical health problems requiring a proper psychiatric and medical management.

Adult↗
PubMed2002

Chronic insomnia is associated with a shift of interleukin-6 and tumor necrosis factor secretion from nighttime to daytime.

Chronic insomnia, by far the most commonly encountered sleep disorder in medical practice, is characterized by difficulty falling or staying asleep at night and increased fatigue during the day. Interleukin-6 (IL-6) and tumor necrosis factor (TNF) are fatigue-inducing cytokines, and the daytime secretion of IL-6 is negatively influenced by the quantity and quality of the previous night's sleep. We hypothesize that the poor quality of insomniacs' sleep is associated with a hypersecretion of these 2 cytokines during the daytime, which, in turn, correlates with the fatigue experienced by these patients. Eleven young insomniacs (6 men and 5 women) and 11 (8 men and 3 women) age- and body mass index (BMI)-matched healthy controls participated in the study. Subjects were recorded in the sleep laboratory for 4 consecutive nights and serial 24-hour plasma measures of IL-6 and TNF were obtained during the 4th day. Insomniacs compared to controls slept poorly (sleep latency and wake were increased, whereas percentage sleep time was decreased during baseline nights, all P <.05). The mean 24-hour IL-6 and TNF secretions were not different between insomniacs and controls. However, the difference in the change (increase) of IL-6 plasma levels from midafternoon (2 PM) to evening (9 PM) between insomniacs and controls was significant (P <.01). Furthermore, cosinor analysis showed a significant shift of the major peak of IL-6 secretion from nighttime (4 AM) to evening (7 PM) in insomniacs compared to controls (P <.05). Also, while TNF secretion in controls showed a distinct circadian rhythm with a peak close and prior to the offset of sleep (P <.05), such a rhythm was not present in insomniacs. Finally, daytime secretion of TNF in insomniacs was characterized by a regular rhythm of 4 hours (P <.05); such a distinct periodicity was not present in controls. We conclude that chronic insomnia is associated with a shift of IL-6 and TNF secretion from nighttime to daytime, which may explain the daytime fatigue and performance decrements associated with this disorder. The daytime shift of IL-6 and TNF secretion, combined with a 24-hour hypersecretion of cortisol, an arousal hormone, may explain the insomniacs' daytime fatigue and difficulty falling asleep.

Adult↗
PubMed2001

Prevalence of sleep-disordered breathing in women: effects of gender.

The prevalence of sleep-disordered breathing has not been well studied in women, especially in terms of the effects of age, body mass index (BMI), and menopause. We evaluated this question using a two-phase random sample from the general population. In Phase I, 12,219 women and 4,364 men ranging in age from 20 to 100 yr were interviewed; and in Phase II, 1,000 women and 741 men of the Phase I subjects were selected for one night of sleep laboratory evaluation. The results of our study indicated that, for clinically defined sleep apnea (apnea/hypopnea index > or = 10 and daytime symptoms), men had a prevalence of 3.9% and women 1.2%, resulting in an overall ratio of sleep apnea for men to women of 3.3:1 (p = 0.0006). The prevalence of sleep apnea was quite low in premenopausal women (0.6%) as well as postmenopausal women with hormone replacement therapy (HRT) (0.5%). Further, in these women the presence of sleep apnea appeared to be associated exclusively with obesity (BMI > or = 32.3 kg/m2). Postmenopausal women without HRT had a prevalence of sleep apnea that was significantly higher than the prevalence in premenopausal women with HRT (2.7 versus 0.6%, p = 0.02) and was more similar to the prevalence in men (3.9%), although it remained significantly less when controlling for age and BMI (p = 0.001). These data combined indicate that menopause is a significant risk factor for sleep apnea in women and that hormone replacement appears to be associated with reduced risk.

Adult↗
PubMed2001

Middle-aged men show higher sensitivity of sleep to the arousing effects of corticotropin-releasing hormone than young men: clinical implications.

The prevalence of insomnia associated with emotional stress increases markedly in middle-age. Both the top and end hormones of the hypothalamic-pituitary-adrenal axis, i.e. CRH and glucocorticoids, stimulate arousal/wakefulness and inhibit slow wave (deep) sleep in experimental animals and man. The objective of this study was to test the hypothesis that middle-age is characterized by increased sensitivity to the sleep-disturbing effects of the hypothalamic-pituitary-adrenal axis. We studied 12 healthy middle-aged (45.1 +/- 4.9) and 12 healthy young (22.7 +/- 2.8) men by monitoring their sleep by polysomnography for 4 consecutive nights, including in tandem 1 adaptation and 2 baseline nights and a night during which we administered equipotent doses of ovine CRH (1 microg/kg, iv bolus) 10 min after sleep onset. Analyses included comparisons within and between groups using multiple ANOVA and regression analysis. Although both middle-aged and young men responded to CRH with similar elevations of ACTH and cortisol, the former had significantly more wakefulness and suppression of slow wave sleep compared with baseline sleep; in contrast, the latter showed no change. Also, comparison of the change in sleep patterns from baseline to the CRH night in the young men to the respective change observed in middle-aged men showed that middle-age was associated with significantly higher wakefulness and significantly greater decrease in slow wave sleep than in young age. We conclude that middle-aged men show increased vulnerability of sleep to stress hormones, possibly resulting in impairments in the quality of sleep during periods of stress. We suggest that changes in sleep physiology associated with middle-age play a significant role in the marked increase of prevalence of insomnia in middle-age.

Adrenocorticotropic Hormone↗
PubMed2001

Chronic insomnia is associated with nyctohemeral activation of the hypothalamic-pituitary-adrenal axis: clinical implications.

Although insomnia is, by far, the most commonly encountered sleep disorder in medical practice, our knowledge in regard to its neurobiology and medical significance is limited. Activation of the hypothalamic-pituitary-adrenal axis leads to arousal and sleeplessness in animals and humans; however, there is a paucity of data regarding the activity of the hypothalamic-pituitary-adrenal axis in insomniacs. We hypothesized that chronic insomnia is associated with increased plasma levels of ACTH and cortisol. Eleven young insomniacs (6 men and 5 women) and 13 healthy controls (9 men and 4 women) without sleep disturbances, matched for age and body mass index, were monitored in the sleep laboratory for 4 consecutive nights, whereas serial 24-h plasma measures of ACTH and cortisol were obtained during the fourth day. Insomniacs, compared with controls, slept poorly (significantly higher sleep latency and wake during baseline nights). The 24-h ACTH and cortisol secretions were significantly higher in insomniacs, compared with normal controls (4.2 +/- 0.3 vs. 3.3 +/- 0.3 pM, P = 0.04; and 218.0 +/- 11.0 vs. 190.4 +/- 8.3 nM, P = 0.07). Within the 24-h period, the greatest elevations were observed in the evening and first half of the night. Also, insomniacs with a high degree of objective sleep disturbance (% sleep time < 70), compared with those with a low degree of sleep disturbance, secreted a higher amount of cortisol. Pulsatile analysis revealed a significantly higher number of peaks per 24 h in insomniacs than in controls (P < 0.05), whereas cosinor analysis showed no differences in the temporal pattern of ACTH or cortisol secretion between insomniacs and controls. We conclude that insomnia is associated with an overall increase of ACTH and cortisol secretion, which, however, retains a normal circadian pattern. These findings are consistent with a disorder of central nervous system hyperarousal rather than one of sleep loss, which is usually associated with no change or decrease in cortisol secretion or a circadian disturbance. Chronic activation of the hypothalamic-pituitary-adrenal axis in insomnia suggests that insomniacs are at risk not only for mental disorders, i.e. chronic anxiety and depression, but also for significant medical morbidity associated with such activation. The therapeutic goal in insomnia should be to decrease the overall level of physiologic and emotional arousal, and not just to improve the nighttime sleep.

Adrenocorticotropic Hormone↗
PubMed2000

Hypnic headache associated with stage 3 slow wave sleep.

We describe the polysomnographic data of a 79-year-old woman with an 11-year history of nocturnal headaches that were clinically consistent with hypnic headache. A polysomnographic study showed arousal at stage 3 slow wave sleep because of a headache episode. Although this finding could be nonspecific, it suggests the possible relationship between stage 3 slow wave sleep and hypnic headache.

Aged↗
PubMed1999

DSM-III-R co-morbidity in benzodiazepine dependence.

UNLABELLED: AIM, SAMPLE AND MEASURES: Co-morbidity has been shown to influence the clinical course of mental disorders. This paper describes DSM-III-R 1-month co-morbidity across axes I, II and III in a sample of 153 benzodiazepine dependents. All patients were evaluated through several in-depth clinical interviews across all five DSM-III-R axes. RESULTS: Extensive co-morbidity existed across three DSM-III-R axes. All patients had at least one diagnosis in axis I; 81 (52.9%) in axis II and 50 (32.7%) in axis III. The most prevalent diagnoses were: insomnia, anxiety disorders and affective disorders in axis I; obsessive-compulsive, histrionic and dependent personality disorders in axis II and rheumatological, neurological and cardiovascular disorders in axis III. CONCLUSIONS: There were no cases of benzodiazepine dependence appearing alone. There were associations within and between axes, suggesting potential predisposing factors and a sequential model for benzodiazepine dependence is proposed. The findings reinforce the need for exhaustive diagnostic evaluation of patients prior to prescribing benzodiazepine.

Adult↗
PubMed1998

Chronic insomnia and activity of the stress system: a preliminary study.

The aim of this study was to assess whether there is an association between chronic insomnia and the activity of the stress system. Fifteen young adult insomniacs (<40 years) were studied. After an adaptation night, each subject was recorded in the sleep laboratory for three consecutive nights. During this period, 24-hour urine specimens were collected for measurements of urinary free cortisol (UFC), catecholamines, and growth hormone (GH). The 24-hour UFC levels were positively correlated with total wake time (p=0.05). In addition, 24-hour urinary levels of catecholamine metabolites, DHPG, and DOPAC were positively correlated with percent stage 1 sleep (p<0.05) and wake time after sleep onset (WTASO) (p<0.05). Norepinephrine tended to correlate positively with percent stage 1 sleep (p=0.063) and WTASO (p=0.074), and negatively with percent slow-wave sleep (p=0.059). Twenty-four-hour urinary GH excretion was detectable in only three insomniacs, two of whom had low indices of sleep disturbance. We conclude that, in chronic insomnia, the activity of both limbs of the stress system (i.e., the HPA axis and the sympathetic system) relates positively to the degree of objective sleep disturbance.

Adult↗
PubMed1997

Periodic leg movements in sleep in essential hypertension.

The presence of periodic leg movements in sleep (PLMS) was assessed in 91 subjects diagnosed with essential hypertension. More than 18 per cent of the sample had PLMS, which is considerably higher than in normal controls. Also, the prevalence was significantly correlated with the severity of hypertension, as well as with age. Periodic leg movements in sleep were more frequent in the first few hours of the sleep period and during sleep stages 1 and 2. The arousing effect of PLMS was minimal, with only 17 per cent of all events related to an EEG arousal. Our results suggest that PLMS are common in people with essential hypertension, although they do not seem to be associated with any particular sleep disorder.

Adult↗
PubMed1997

Rapid eye movement sleep correlates with the overall activities of the hypothalamic-pituitary-adrenal axis and sympathetic system in healthy humans.

To assess the association of the overall amount of rapid eye movement (REM) sleep and the activities of the hypothalamic-pituitary-adrenal axis and sympathetic system, we performed polysomnography and measured 24-h urinary free cortisol and catecholamine excretion in 21 healthy adults. After an adaptation night, each subject was recorded in the sleep laboratory for 3 consecutive nights while 24-h urine specimens were collected. Urinary free cortisol, epinephrine, dihydroxyphenylglycol, and dihydroxyphenylacetic acid levels were significantly and positively correlated with the average values of percent REM sleep (P < 0.05). There were no correlations between hormone values and REM latency, other variables of REM distribution, or REM density, an index of phasic activity during REM sleep. The positive correlations between stress system activity and REM sleep are consistent with hormonal and sleep alterations in melancholic depression, a state characterized by increased cortisol and catecholamine secretion.

Adult↗
PubMed1996

Benzodiazepine types in high versus therapeutic dose dependence.

Two types of benzodiazepine dependence have been described: high vs. therapeutic dose dependence. So far, no systematic research has been conducted regarding the frequency with which the various benzodiazepines are represented in one type or the other. In this study, 153 dependent patients using 14 different benzodiazepines were evaluated to assess the prevalence of their use among high vs. therapeutic dose dependents. Triazolam was the single drug most frequently used by high-dose dependents, followed by Lorazepam. No significant differences were found among benzodiazepines regarding their use by therapeutic dose dependents. Our data shows that pharmacokinetic and pharmacodynamic factors appear to be related to the frequency with which the different benzodiazepines are used by high and therapeutic dose dependents.

Adult↗
PubMed1996

Narcolepsy-cataplexy and loss of sphincter control.

We describe the case of a 34-year-old man who presented intermittent faecal incontinence as a manifestation of cataplexy. The patient's sleep history was positive for the full narcoleptic tetrad (sleep attacks, cataplexy, sleep paralysis and hypnagogic hallucinations) while extensive neuropsychiatric work up was negative for any neurologic or psychiatric illness. Repeat polysomnograms (including a polysomnogram with a full seizure montage) were positive for pathologic sleepiness, but there was no evidence of a seizure disorder. The course of the patient's symptomatology and the favourable response of his symptoms to stimulants and imipramine support the theory that his intermittent loss of sphincter control is part of his narcolepsy-cataplexy.

Adult↗
PubMed1996

Daytime sleepiness and REM abnormalities in Prader-Willi syndrome: evidence of generalized hypoarousal.

The aim of this study was to clarify the nature of the sleep abnormalities (excessive daytime sleepiness [EDS] and rapid eye movement [REM] sleep alterations) in Prader-Willi; Syndrome (PWS). Eight PWS patients, 15 normal, 16 narcoleptic, and 16 obese subjects were recorded in the sleep laboratory, both during daytime and nighttime. A principal-finding was that EDS in PWS was associated with an increased amount and depth of sleep. In PWS patients with EDS, compared to those PWS patients without EDS or the narcoleptic, obese, and normal groups, there were significant decreases in wakefulness and increases in percentage of sleep time (ST) and slow-wave sleep (SWS) both during daytime and nighttime testing. Also, in the adult PWS subjects (n = 6), in contrast to normal narcoleptic subjects, intensity of EDS was correlated with increased nocturnal percentage of ST and SWS and % SWS was positively correlated with % ST (both during daytime and nighttime testing). Another principal finding was that in PWS there is a unique alteration of the distribution of REM sleep in relation to controls. PWS patients with EDS or shortened nocturnal REM latencies showed a significantly increased number of REM periods, and a decreased average REM interval between REM periods compared to PWS patients with nonshortened nocturnal REM latencies or to the three control groups. Our data suggest that EDS and REM abnormalities in PWS are not manifestations of a narcoleptic-type syndrome or consequences of obesity. We propose that generalized 24-hour hypoarousal is the primary mechanism underlying the sleep abnormalities in PWS patients.

Adolescent↗
PubMed1995

Delta sleep-inducing peptide in normal humans and in patients with sleep apnea and narcolepsy.

We measured morning plasma concentrations of delta sleep-inducing-peptide-like-immunoreactivity (DSIP-LI) in 9 sleep apnea patients, 10 narcolepsy patients, and 11 normal controls. Comparisons between the three groups showed no significant differences, although there was a trend toward association with low levels of DSIP-LI in the narcoleptic group, particularly in patients not using medications. No differences were found in the morning or evening plasma DSIP-LI levels in a second group of 11 normal controls and 8 sleep apneics. Our findings do not appear to support a biological marker role of disease activity for single measures of plasma DSIP in sleep apnea.

Adult↗
PubMed1995

Benzodiazepine withdrawal syndrome seizures.

In this study, we present five cases of seizures following withdrawal of flunitrazepam, lorazepam, or triazolam, representing 3% of a sample consisting of 153 patients dependent on benzodiazepines. Both abrupt cessation of benzodiazepine intake and high-dose use seem to be critical for the appearance of seizures. Pharmacological features, such as short elimination half-life and high potency, might explain the higher risk of seizures observed in these patients.

Adult↗