Julio Fernandez-Mendoza

Insomnia With Objective Short Sleep Duration and Incident Hypertension The Penn State Cohort

Insomnia with objective short sleep duration appears to be a biologically more severe phenotype of the disorder. No longitudinal study to date has examined the association of this type of insomnia with incident hypertension using polysomnography. From a random, general population sample of 1741 adults of the Penn State Cohort, 1395 were followed-up after 7.5 years, and 786 did not have hypertension at baseline. Hypertension was determined by a self-report of receiving treatment for high blood pressure. Chronic insomnia was defined as a complaint of insomnia lasting ≥1 year, whereas poor sleep was defined as moderate-to-severe sleep difficulties. All of the subjects underwent 8-hour polysomnography. Sleep-disordered breathing (SDB) was defined as an obstructive apnea/hypopnea index ≥5. We used the median polysomnographic percentage of sleep time to define short sleep duration (ie, <6 hours). We controlled for sex, race, age, caffeine, cigarettes and alcohol consumption, depression, sleep-disordered breathing, diabetes mellitus, obesity, and blood pressure in our analyses. Compared with normal sleepers who slept ≥6 hours, the highest risk for incident hypertension was in chronic insomniacs with short sleep duration (odds ratio, 3.8 [95% CI, 1.6–9.0]). The risk for incident hypertension in poor sleepers with short sleep duration was significantly increased but became marginally significant after controlling for obesity (odds ratio, 1.6 [95% CI, 0.9–2.8]). Chronic insomnia with short sleep duration is associated with an increased risk for incident hypertension in a degree comparable to sleep-disordered breathing. Objective short sleep duration in insomnia may serve as a useful predictor of the biological severity of the disorder.

Risk Factors for Incident Chronic Insomnia: A General Population Prospective Study

OBJECTIVE The few population-based, prospective studies that have examined risk factors of incident insomnia were limited by small sample size, short follow-up, and lack of data on medical disorders or polysomnography. We prospectively examined the associations between demographics, behavioral factors, psychiatric and medical disorders, and polysomnography with incident chronic insomnia. METHODS From a random, general population sample of 1741 individuals of the adult Penn State Sleep Cohort, 1395 were followed-up after 7.5 years. Only subjects without chronic insomnia at baseline (n = 1246) were included in this study. Structured medical and psychiatric history, personality testing, and 8-h polysomnography were obtained at baseline. Structured sleep history was obtained at baseline and follow-up. RESULTS Incidence of chronic insomnia was 9.3%, with a higher incidence in women (12.9%) than in men (6.2%). Younger age (20-35 years), non-white ethnicity, and obesity increased the risk of chronic insomnia. Poor sleep and mental health were stronger predictors of incident chronic insomnia compared to physical health. Higher scores in MMPI-2, indicating maladaptive personality traits, and excessive use of coffee at baseline predicted incident chronic insomnia. Polysomnographic variables, such as short sleep duration or sleep apnea, did not predict incident chronic insomnia. CONCLUSION Mental health, poor sleep, and obesity, but not sleep apnea, are significant risk factors for incident chronic insomnia. Focusing on these more vulnerable groups and addressing the modifiable risk factors may help reduce the incident of chronic insomnia, a common and chronic sleep disorder associated with significant medical and psychiatric morbidity and mortality.

Cognitive-emotional hyperarousal as a premorbid characteristic of individuals vulnerable to insomnia.

Objective: To examine whether cognitive-emotional hyperarousal is a premorbid characteristic of middle-aged and young good sleepers vulnerable to stress-related insomnia. Methods: Self-reported information was collected from two samples of 305 middle-aged and 196 young adults. From those adults, 149 middle-aged (50.34 ± 4.47 years) and 85 young (20.19 ± 1.31 years) good sleepers were selected for the present study. The Ford Insomnia Response to Stress Test (FIRST) was used to measure vulnerability to stress-related insomnia. Trait measures of personality, arousability, rumination, presleep arousal, and coping skills were entered as predictors in the linear regression models, at the same time controlling for gender, depression, and anxiety. Results: The regression models showed that arousability (&bgr; = 0.546), neuroticism (&bgr; = 0.413), perceived stress (&bgr; = 0.375), and rumination (&bgr; = 0.214) were associated with FIRST scores in middle-aged adults. Among young adults, the regression models revealed that presleep cognitive arousal (&bgr; = 0.448), arousability (&bgr; = 0.426), neuroticism (&bgr; = 0.320), presleep somatic arousal (&bgr; = 0.290), emotion-oriented coping (&bgr; = 0.220), and rumination (&bgr; = 0.212) were associated with FIRST scores. Finally, individuals with high FIRST scores did not show lower scores in measures of cognitive-emotional hyperarousal compared with chronic insomniacs. Conclusions: These data suggest that cognitive-emotional hyperarousal may be a premorbid characteristic of subjects vulnerable to insomnia. It seems that maladaptive coping stress strategies and cognitive-emotional hyperarousal predispose to the development of insomnia and that interventions targeting these characteristics may be important in the prevention and treatment of chronic insomnia. BMI = body mass index; DSM-IV-TR = Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition, Text Revised; FIRST = Ford Insomnia Response to Stress Test; ISI = Insomnia Severity Index; PSQI = Pittsburgh Sleep Quality Index.

Sleep misperception and chronic insomnia in the general population: role of objective sleep duration and psychological profiles.

Objective: To examine the role of objective sleep duration, a novel marker in phenotyping insomnia, and psychological profiles on sleep misperception in a large, general population sample. Sleep misperception is considered by some investigators a common characteristic of chronic insomnia, whereas others propose it as a separate diagnosis. The frequency and the determinants of sleep misperception in general population samples are unknown. Methods: A total of 142 insomniacs and 724 controls selected from a general random sample of 1,741 individuals (aged ≥20 years) underwent a polysomnographic evaluation, completed the Minnesota Multiphasic Personality Inventory-2, and were split into two groups based on their objective sleep duration: “normal sleep duration” (≥6 hours) and “short sleep duration” (<6 hours). Results: The discrepancy between subjective and objective sleep duration was determined by two independent factors. Short sleepers reported more sleep than they objectively had, and insomniacs reported less sleep than controls with similar objective sleep duration. The additive effect of these two factors resulted in underestimation only in insomniacs with normal sleep duration. Insomniacs with normal sleep duration showed a Minnesota Multiphasic Personality Inventory-2 profile of high depression and anxiety and low ego strength, whereas insomniacs with short sleep duration showed a profile of a medical disorder. Conclusions: Underestimation of sleep duration is prevalent among insomniacs with objective normal sleep duration. Anxious-ruminative traits and poor resources for coping with stress seem to mediate the underestimation of sleep duration. These data further support the validity and clinical utility of objective sleep measures in phenotyping insomnia. BMI = body mass index; DSM-IV = Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition; MANCOVA = multivariate analysis of covariance; MMPI-2 = Minnesota Multiphasic Personality Inventory-2; PLMS = periodic limb movements; SDB = sleep disordered breathing.

Clinical and polysomnographic predictors of the natural history of poor sleep in the general population.

STUDY OBJECTIVES Approximately 8-10% of the general population suffers from chronic insomnia, whereas another 20-30% of the population has insomnia symptoms at any given time (i.e., poor sleep). However, few longitudinal studies have examined risk factors of the natural history of poor sleep, and none have examined the role of polysomnographic (PSG) variables. DESIGN Representative longitudinal study. SETTING Sleep laboratory. PARTICIPANTS From a random, general population sample of 1,741 individuals of the adult Penn State Cohort, 1,395 were followed up after 7.5 yr. MEASUREMENTS Full medical evaluation and 1-night PSG at baseline and telephone interview at follow-up. RESULTS The rate of incident poor sleep was 18.4%. Physical (e.g., obesity, sleep apnea, and ulcer) and mental (e.g., depression) health conditions and behavioral factors (e.g., smoking and alcohol consumption) increased the odds of incident poor sleep as compared to normal sleep. The rates of persistent, remitted, and poor sleepers who developed chronic insomnia were 39%, 44%, and 17%, respectively. Risk factors for persistent poor sleep were physical health conditions combined with psychologic distress. Shorter objective sleep duration and a family history of sleep problems were risk factors for poor sleep evolving into chronic insomnia. CONCLUSIONS Poor sleep appears to be primarily a symptom of physical and mental health conditions, whereas the persistence of poor sleep is associated with psychologic distress. Importantly, sleep apnea appears to be associated with incident poor sleep but not with chronic insomnia. Finally, this study suggests that objective short sleep duration in poor sleepers is a biologic marker of genetic predisposition to chronic insomnia.

Unveiling the longitudinal association between short sleep duration and the incidence of obesity: the Penn State Cohort.

Objective:Several epidemiologic, longitudinal studies have reported that short sleep duration is a risk factor for the incidence of obesity. However, the vast majority of these studies used self-reported measures of sleep duration and did not examine the role of objective short sleep duration, subjective sleep disturbances and emotional stress.Design:Longitudinal, population-based study.Subjects:We studied a random sample of 815 non-obese adults from the Penn State Cohort in the sleep laboratory for one night using polysomnography (PSG) and followed them up for a mean of 7.5 years. Subjective and objective measures of sleep as well as emotional stress were obtained at baseline. Obesity was defined as a body mass index (BMI) ⩾30 kg/ m-2.Results:The incidence of obesity was 15% and it was significantly higher in women and in individuals who reported sleep disturbances, shorter sleep duration and higher emotional stress. Significant mediating effects showed that individuals with subjective sleep disturbances who developed obesity reported the shortest sleep duration and the highest emotional stress, and that subjective sleep disturbances and emotional stress were independent predictors of incident obesity. Further analyses revealed that the association between short sleep duration, subjective sleep disturbances and emotional stress with incident obesity was stronger in young and middle-age adults. Objective short sleep duration was not associated with a significantly increased risk of incident obesity.Conclusion:Self-reported short sleep duration in non-obese individuals at risk of developing obesity is a surrogate marker of emotional stress and subjective sleep disturbances. Objective short sleep duration is not associated with a significant increased risk of incident obesity. The detection and treatment of sleep disturbances and emotional stress should become a target of our preventive strategies against obesity.

Persistent Insomnia: the Role of Objective Short Sleep Duration and Mental Health

STUDY OBJECTIVES Few population-based, longitudinal studies have examined risk factors for persistent insomnia, and the results are inconsistent. Furthermore, none of these studies have examined the role of polysomnographic (PSG) variables such as sleep duration or sleep apnea on the persistence of insomnia. DESIGN Representative longitudinal study. SETTING Sleep laboratory. PARTICIPANTS From a random, general population sample of 1741 individuals of the adult Penn State Cohort, 1395 were followed-up after 7.5 years. MEASUREMENTS Individuals underwent one-night PSG and full medical evaluation at baseline and a telephone interview at follow-up. PSG sleep duration was analyzed as a continuous variable and as a categorical variable: < 6 h sleep (short sleep duration) and ≥ 6 h sleep (longer sleep duration). RESULTS The rates of insomnia persistence, partial remission, and full remission were 44.0%, 30.0%, and 26.0%, respectively. Objective short sleep duration significantly increased the odds of persistent insomnia as compared to normal sleep (OR = 3.19) and to fully remitted insomnia (OR = 4.92). Mental health problems at baseline were strongly associated with persistent insomnia as compared to normal sleep (OR = 9.67) and to a lesser degree compared to fully remitted insomnia (OR = 3.68). Smoking, caffeine, and alcohol consumption and sleep apnea did not predict persistent insomnia. CONCLUSIONS Objective short sleep duration and mental health problems are the strongest predictors of persistent insomnia. These data further support the validity and clinical utility of objective short sleep duration as a novel marker of the biological severity of insomnia.

Insomnia and sleep quality among primary care physicians with low and high burnout levels

OBJECTIVE The aim of this study was to assess insomnia and sleep quality in primary care physicians with low and high burnout scores. METHODS A representative sample of 240 physicians was drawn from 70 medical centers in Madrid, Spain. Based on quartile splits of the overall index of the Shirom-Melamed Burnout Questionnaire, 55 participants were allocated to a low-burnout group, and 58 were included in a high-burnout group. The questionnaire also included sociodemographic data, insomnia symptomatology, and the Pittsburgh Sleep Quality Index. RESULTS Of the total sample, 18.8% met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for insomnia diagnoses. More individuals with high burnout scores (21.1%) than individuals with low burnout scores (6.9%) fulfilled these criteria. Results of multivariate logistic regression analyses showed that burnout was the only variable related to insomnia diagnoses (odds ratio=7.56; 95% confidence interval=2.38-14.02). Furthermore, the results of multivariate analysis of covariance, after adjustments for sociodemographic variables, indicated that subjects from the high-burnout group scored significantly higher than subjects from the low-burnout group on the global sleep quality index and its components, indicating significantly greater disturbed sleep for the former. CONCLUSION The results of the present study provide support for a clear relationship between burnout and disturbed sleep, as shown by the high prevalence of insomnia and poor sleep quality among physicians with high levels of burnout.

Insomnia and its Impact on Physical and Mental Health

In contrast to the association of insomnia with mental health, its association with physical health has remained largely unexplored until recently. Based on findings that insomnia with objective short sleep duration is associated with activation of both limbs of the stress system and other indices of physiological hyperarousal, which should adversely affect physical and mental health, we have recently demonstrated that this insomnia phenotype is associated with a significant risk of cardiometabolic and neurocognitive morbidity and mortality. In contrast, insomnia with normal sleep duration is associated with sleep misperception and cognitive-emotional arousal, but not with signs of physiological hyperarousal or cardiometabolic or neurocognitive morbidity. Interestingly, both insomnia phenotypes are associated with mental health, although most likely through different pathophysiological mechanisms. We propose that objective measures of sleep duration may become part of the routine evaluation and diagnosis of insomnia, and that these two insomnia phenotypes may respond differentially to biological versus psychological treatments.

Sleep apnoea and visceral adiposity in middle-aged male and female subjects

In obese male subjects, visceral adiposity has been associated with obstructive sleep apnoea (OSA), while studies in overweight males and females are limited. Our goal was to examine the association between OSA and visceral fat in a relatively nonobese population and assess the effects of 2 months placebo-controlled continuous positive airway pressure (CPAP) use on abdominal fat. 81 subjects, 22 middle-aged males and 20 post-menopausal females with OSA, and 19 male and 20 female controls were studied in the sleep laboratory for four nights. Abdominal (visceral (VAT) and subcutaneous (SAT) adipose tissue) and liver fat were assessed with computed tomography. OSA patients were re-assessed post-CPAP and post sham-CPAP. Apnoeic males had significantly higher VAT than controls, while apnoeic females had higher SAT than controls. In both sexes, OSA was associated with increased liver fat. In males, apnoea was associated with VAT whereas in females it was associated with subcutaneous, visceral and total fat. CPAP did not affect abdominal and liver fat. In overweight males, visceral adiposity is associated with OSA whereas in females it is associated with global adiposity. In overweight males, our therapeutic goal should be the reduction of visceral adiposity and its metabolic correlates, whereas, in females, weight loss may be sufficient. Short-term CPAP treatment does not affect general, abdominal or intra-hepatic adiposity.