Daniel J. Taylor

Quantitative criteria for insomnia

Formal diagnostic systems (DSM-IV, ICSD, and ICD-10) do not provide adequate quantitative criteria to diagnose insomnia. This may not present a serious problem in clinical settings where extensive interviews determine the need for clinical management. However, lack of standard criteria introduce disruptive variability into the insomnia research domain. The present study reviewed two decades of psychology clinical trials for insomnia to determine common practice with regard to frequency, severity, and duration criteria for insomnia. Modal patterns established frequency (> or =3 nights a week) and duration (> or =6 months) standard criteria. We then applied four versions of severity criteria to a random sample and used sensitivity-specificity analyses to identify the most valid criterion. We found that severity of sleep onset latency or wake time after sleep onset of: (a) > or =31 min; (b) occurring > or =3 nights a week; (c) for > or =6 months are the most defensible quantitative criteria for insomnia.

Insomnia as a health risk factor

This article reviewed insomnia epidemiological research, identifying areas where insomnia was a risk factor and isolating areas deserving of further investigation. Insomnia was consistently predictive of depression, anxiety disorders, other psychological disorders, alcohol abuse or dependence, drug abuse or dependence, and suicide, indicating insomnia is a risk factor for these difficulties. Additionally, insomnia was related to decreased immune functioning. The data were inconclusive regarding insomnia as a risk factor for cardiovascular disease and mortality, but sleep medication use was predictive of mortality. These results must be tempered with the knowledge that significant weaknesses existed in the studies reviewed. The main weaknesses were inadequate definition of insomnia and inadequate control for alternative explanations. Despite these limitations, this review suggests that insomnia is a risk factor for poor mental and physical health.

Sleep tendency during extended wakefulness: insights into adolescent sleep regulation and behavior.

Sleep tendency (latency to sleep onset) was examined during extended waking in prepubertal and mature adolescents to determine whether sleep pressure is lower near bedtime in the latter group. Participants were nine prepubertal (pubertal stage Tanner 1, mean age 11.1 years, SD ± 1.3 years, five males) and 11 pubertally mature adolescents (Tanner 5, 13.9 ± 1.2 years, three males). They spent 10 nights at home on an identical fixed 10‐h sleep schedule followed by a 36‐h constant routine with sleep latency tests at 2‐h intervals using standard polysomnography. Saliva was collected to assess dim‐light melatonin onset (DLMO) phase. DLMO was earlier in the Tanner 1 (mean clock time = 20:33 hours, SD = 49 min) than Tanner 5 group (21:29 hours ± 42 min). Sleep latency compared at a ‘critical period’ spanning 12.5 (20:30 hours clock time) to 18.5 h (02:30 hours) after waking did not differ at 20:30 hours, but was shorter for the Tanner 1 group at 22:30 hours (Tanner 1 = 9.2 ± 6.3 min; Tanner 5 = 15.7 ± 5.8 min), 00:30 hours (Tanner 1 = 3.6 ± 1.7 min; Tanner 5 = 9.0 ± 6.4 min), and 02:30 hours (Tanner 1 = 2.0 ± 1.7 min; Tanner 5 = 4.3 ± 3.2 min; trend). These differences were apparent controlling for circadian phase by partial correlation. Sleep tendency after 14.5, 16.5, and 18.5 h awake was lower in mature versus prepubertal adolescents, supporting our hypothesis that a developmental change of intrinsic sleep–wake regulation may provide physiologically mediated ‘permission’ for later bedtimes in older adolescents.

Epidemiology of Sleep : Age, Gender, and Ethnicity

Contents: Goals and Distinctive Characteristics of This Survey. A Review of Epidemiological Studies of Insomnia and Sleep. Methods of This Survey. An Archive of Normal Sleep. An Archive of Insomnia. An Archive of the Sleep of African Americans. Summary of Main Findings. Appendix: Alphabetical Listing of Abbreviations and Acronyms.

Socioeconomic status and insomnia

This investigation compared the likelihood of insomnia and insomnia-related health consequences among individuals of different socioeconomic status. A random-digit dialing procedure was used to recruit at least 50 men and 50 women in each age decade from 20 to 80+ years old. Participants completed 2 weeks of sleep diaries as well as questionnaires related to fatigue, sleepiness, and psychological distress. Socioeconomic status was measured by education status assessed at 3 different levels: individual, household, and community. Results indicated that individuals of lower individual and household education were significantly more likely to experience insomnia even after researchers accounted for ethnicity, gender, and age. Additionally, individuals with fewer years of education, particularly those who had dropped out of high school, experienced greater subjective impairment because of their insomnia.

Patterns and consequences of inadequate sleep in college students: substance use and motor vehicle accidents

We examined college sleep patterns and consequences using a cross-sectional design. We found that students get insufficient sleep and frequently use medication and alcohol as sleep aids, use stimulants as alertness aids, and fall asleep at the wheel, or have motor vehicle accidents due to sleepiness. Future studies should focus on effective interventions for sleep in college students.

Epidemiology of insomnia in college students: relationship with mental health, quality of life, and substance use difficulties.

The purpose of this study was to evaluate the prevalence and correlates of insomnia using rigorous diagnostic criteria and a comprehensive assessment battery. In a large sample (N=1,074) of college students (mean age 20.39years), participants were asked to complete a week-long sleep diary and comprehensive questionnaire packet assessing recommended daytime functioning domains (i.e., fatigue, quality of life, depression, anxiety, stress, academic performance, substance use) during the academic year. A significant portion of this sample of college students met proposed DSM-5 criteria for chronic insomnia (9.5%). The chronic insomnia group reported significantly worse sleep, fatigue, depression, anxiety, stress, and quality of life, and greater hypnotic and stimulant use for sleep problems. There were no differences between groups on excessive daytime sleepiness, academic performance, or substance use. This was a rigorous and comprehensive assessment of the prevalence and psychosocial correlates of insomnia. Insomnia is a significant problem in college students and should be regularly assessed. More research is also needed to guide treatment in this population.

Cognitive and behavioural therapy for insomnia (CBT-I) in psychiatric populations: a systematic review.

Abstract Insomnia is highly co-morbid with psychiatric disorders, making it a frequent issue in treatment planning in psychiatric clinics. Research has also shown that although insomnia may originally precede or be a consequence of a psychiatric disorder, insomnia likely becomes semi-independent, and may exacerbate those disorders if it is not addressed, leading to reduced treatment response. Cognitive behavioural therapy for insomnia (CBT-I) is now recommended as the first line of treatment of primary insomnia. The research reviewed below indicates that CBT-I in patients with co-morbid depression, anxiety, post-traumatic stress disorder (PTSD), and substance abuse disorders is generally effective for insomnia and sometimes the co-morbid disorder as well. Although more research is needed before definitive recommendations can be made, it appears as though CBT-I is a viable approach to treating the patient with co-morbid insomnia and psychiatric disorders.

The Relation Between Smoking and Sleep: The Influence of Smoking Level, Health, and Psychological Variables

The relation between smoking and sleep was examined in a randomly selected sample of 769 individuals (379 men and 390 women, ages 20 to 98). Participants completed 2 weeks of sleep diaries, provided a global report on their sleep, indicated the number of cigarettes smoked per day, and supplied information on health, depressive symptoms, anxiety, and caffeine and alcohol use. After controlling for demographic, health, psychological, and behavioral variables, light smoking (< 15 cigarettes per day), but not heavier smoking, was associated with self-reported chronic insomnia and reduced sleep diary total sleep time and time in bed. Smokers did not differ significantly from nonsmokers on diary measures of sleep-onset latency, number of awakenings during the night, wake time after sleep onset, or sleep efficiency.

Which depressive symptoms remain after response to cognitive therapy of depression and predict relapse and recurrence

BACKGROUND Major Depressive Disorder (MDD) is highly prevalent, severely debilitating, and often recurrent. Greater residual depressive symptoms after acute phase treatment predict greater relapse and recurrence. It is unknown, however, which specific depressive symptoms remain and are most predictive. METHOD The current study examined (a) which specific residual symptoms remained after effective treatment with acute phase cognitive therapy (A-CT) for recurrent depression and (b) if any of those specific residual symptoms were risk factors for relapse and recurrence over a 2-year follow-up. RESULTS After completing 20 sessions of A-CT, a substantial proportion of adult responders continued to endorse somatic anxiety (42%), psychological anxiety (37%), middle insomnia (36%), depressed mood (29%), loss of libido (29%), late insomnia (24%), anergia (21%), guilt feelings (18%), early insomnia (17%), and anhedonia (14%), as defined by the 17-item Hamilton Rating Scale for Depression (HRSD). Decreased agitation, increased psychological anxiety, increased loss of appetite, increased loss of libido, and increased hypochondriasis were all risk factors for relapse and recurrence over a 2-year follow-up (all p<.05), after stratifying on number of previous episodes and controlling for age at onset and whether A-CT responders received continuation phase CT instead of assessment only control. LIMITATIONS These findings are based on a limited sample size (n=84), which was modestly restricted in terms of gender, ethnicity, region, and mean education level. CONCLUSIONS These results confirm that residual symptoms are common after A-CT. We hypothesize that treatments, intervention modules, or durations that effect and/or target specific residual symptoms may further reduce depression relapse and recurrence.