New guidelines for diagnosis and treatment of insomnia

Novas diretrizes no diagnóstico e tratamento das insônias

GUIDELINES

New guidelines for diagnosis and treatment of insomnia

Novas diretrizes no diagnóstico e tratamento das insônias

Luciano Ribeiro Pinto Jr.^I; Rosana Cardoso Alves^II; Eliazor Caixeta^III; John Araujo Fontenelle^IV; Andrea Bacellar^V; Dalva Poyares^I; Flavio Aloe^II; Geraldo Rizzo^VI; Gisele Minhoto^VII; Lia Rita Bittencourt^I; Luiz Ataide Jr.^VIII; Márcia Assis^IX; Márcia Pradella-Hallinan^I; Maria Christina Ribeiro Pinto^I; Raimundo Nonato D. Rodrigues^X; Rosa Hasan^II; Ronaldo Fonseca^XI; Stella Tavares^I

^IFederal University, São Paulo SP, Brazil. Brazilian Sleep Association

^IIUniversity, São Paulo SP, Brazil. Brazilian Sleep Association

^IIISchool of Medicine Science, MG, Brazil. Brazilian Sleep Association

^IVFederal University, RN, Brazil. Brazilian Sleep Association

^VCarlos Bacelar Clinic, RJ, Brazil. Brazilian Sleep Association

^VIMoinhos de Vento Hospital, Porto Alegre RS, Brazil. Brazilian Sleep Association

^VIICatolic University, Curitiba PR, Brazil. Brazilian Sleep Association

^VIIIUniversity, PE, Brazil. Brazilian Sleep Association

^IXSão Lucas Hospital, Curitiba PR, Brazil. Brazilian Sleep Association

^XUniversity, Brasília DF, Brazil. Brazilian Sleep Association

^XIState University, São Paulo SP, Brazil. Brazilian Sleep Association

^{Correspondence}

ABSTRACT

The Brazilian Sleep Association brought together specialists in sleep medicine, in order to develop new guidelines on the diagnosis and treatment of insomnias. The following subjects were discussed: concepts, clinical and psychosocial evaluations, recommendations for polysomnography, pharmacological treatment, behavioral and cognitive therapy, comorbidities and insomnia in children. Four levels of evidence were envisaged: standard, recommended, optional and not recommended. For diagnosing of insomnia, psychosocial and polysomnographic investigation were recommended. For non-pharmacological treatment, cognitive behavioral treatment was considered to be standard, while for pharmacological treatment, zolpidem was indicated as the standard drug because of its hypnotic profile, while zopiclone, trazodone and doxepin were recommended.

Key words: insomnia, diagnosis of insomnia, treatment of insomnia, cognitive behavioral therapy.

RESUMO

A Associação Brasileira de Sono reuniu especialistas em medicina do sono com o objetivo de desenvolver novas diretrizes no diagnóstico e tratamento das insônias. Nós consideramos quatro níveis de evidência: padrão, recomendado, opcional e não recomendado. Os tópicos abordados foram: conceito, avaliação clínica e psicossocial, indicação da polissonografia, tratamento farmacológico, terapia comportamental cognitiva, comorbidades e insônia na infância. Para o diagnóstico da insônia, foi recomendada uma avaliação psicossocial e a realização da polissonografia, enquanto que no que se refere ao tratamento, foi estabelecido como padrão a indicação da terapia comportamental cognitiva, e, quanto ao tratamento farmacológico, foi indicado o uso do zolpidem como hipnótico padrão, e sendo recomendado o zopiclone, a trazodona e a doxepina.

Palavras-chave: insônia, diagnóstico da insônia, tratamento da insônia, terapia comportamental cognitiva.

Even today, insomnia remains a clinical entity that is difficult to diagnose and complex to treat, demanding an approach with appropriate strategy and planning. Insomnia, as a symptom, syndrome or disease, has serious social and professional consequences, affecting daily activities and rendering individuals incapable of performing their tasks. It therefore generates a high cost for society.

In November 2008, the Brazilian Sleep Society brought together doctors who specialize in sleep medicine, in São Paulo. The meeting aimed to provide new guidelines for diagnosing and treating insomnia. During this meeting, the following subjects were considered: concepts, clinical and psychosocial evaluations, recommendations for polysomnography, pharmacological treatment, behavioral and cognitive therapy, comorbidities and insomnia in children.

METHOD

Based on searches in the literature for articles, reviews and meta-analyses, five levels of evidence were put forward as recommendations for managing insomnia:

Level I - Randomized trials with low false-positive (alpha) and low false-negative (beta) errors (high power); evidence obtained from meta-analyses on randomized controlled trials; Level II - Randomized trials with high false-positive (alpha) and (or) high false-negative (beta) errors (low power); evidence obtained from at least one randomized controlled trial; Level III - Nonrandomized concurrent cohort comparisons between patients with and without receiving a concomitant nutritional intervention; evidence obtained from at least one well-designed, controlled study, without randomization; Level IV - Nonrandomized historical cohort comparisons between current patients who received a nutritional intervention, and former patients (from the same institution or from the literature) who did not; Level V - Case series without controls; evidence obtained from expert committee reports or opinions and/or clinical experiences from respected authorities. Based on these five levels of evidence, the recommendations for interventions were considered to be: standard (levels I and II); recommended (levels III and IV), optional (level V) and not recommended, when no level of evidence existed^1,2.

Concept (standard)

Insomnia is defined as a disorder that is characterized by difficulty in falling asleep or maintaining sleep. Furthermore, insomnia is also related to dissatisfaction with the quality of sleep, thus resulting in daily physical and emotional symptoms that have an impact on social and cognitive performance³.

Classification (standard)

According to the latest classification of sleep disorders (2005), insomnia is divided into the following forms: acute insomnia, psychophysiological insomnia, paradoxical insomnia, idiopathic insomnia, insomnia associated with mental disorders, insomnia associated with systemic diseases and insomnia associated with inadequate habits^4-6.

Acute insomnia, transitory insomnia or adjustment insomnia

The essential element for this diagnosis is the presence of symptoms of acute insomnia caused by a triggering causal factor that is clearly identified in an individual who previously had a normal sleeping pattern, without insomnia complaints. This clinical condition lasts no longer than one month⁴.

Primary chronic insomnia

In the etiopathogenesis of primary insomnia, three points should be considered: predisposing (genetic and constitutional), precipitating and perpetuating factors. Predisposing factors depend on hyperactivity of the awakening system (stress response mechanisms), hyperactivity of the hypothalamic-pituitary-adrenal axis, anxiety and depression, abnormalities in the mechanisms of sleep-wakefulness homeostasis, abnormalities in the circadian rhythm (circadian sleep-wakefulness control) and abnormalities of the intrinsic mechanisms of sleep-wakefulness control^7-11. The precipitating and perpetuating factors depend on psychosocial factors, behavioral changes and cognitive characteristics.

Primary insomnia can be divided in three subtypes, namely psychophysiological, idiopathic and paradoxical⁴. Psychophysiological insomnia occurs concomitantly with a cognitive hyperalert state that is characterized by anxiety related to the act of sleeping and the presence of neurocognitive symptoms such as fatigue and irritability. Idiopathic insomnia starts before puberty and persists throughout adulthood, and a family history of insomnia is often present. In paradoxical insomnia, subjective complaints of poor quality sleep can be observed, despite the lack of objective sleep abnormalities on polysomnography. This subtype of insomnia is related to sleep misperception.

Associated insomnia

[1] Mental disorder - The essential factor of this type of insomnia is the temporal and causal relationship with an underlying mental disorder. Mood disorders such as depression, dysthymia, cyclothymia, bipolar disorder, anxiety, schizophrenia and somatoform disorders are examples of mental disorders associated with this type of insomnia^3-5,12-18.

[2] Inadequate sleep hygiene - This is related to habits that are inappropriate for good quality of sleep, for example psychologically stressful activities, consumption of caffeine, nicotine, alcohol and heavy meals, vigorous physical activity close to bed time, inconstant time for going to sleeping and waking up, long naps or naps near the main time for sleeping⁴.

[3] Medical condition - This sleep disorder is related to particular medical conditions, for example painful syndromes, infections, metabolic diseases, hyperthyroidism and neurological diseases⁴.

[4] Use of substances or medication - This sleep disorder is related to the use of a drug or substance such as alcohol, stimulants (amphetamine and derivatives) or antidepressives⁴.

Comorbidities

Obstructive sleep apnea

In 1973, Guilleminault et al described the association between insomnia and obstructive sleep apnea, and called it "sleep-insomnia apnea syndrome"¹⁹. The relationship between these two common sleep disorders is complex and unclear. There is a higher incidence of breathing disorders in insomniac patients than there is in the general population^20,21. The severity of insomnia symptoms is strongly correlated with the severity of apnea, thereby characterizing comorbidity. Lichstein et al demonstrated that high proportions of individuals, particularly the elderly, present this combined condition of undiagnosed sleep apnea and insomnia²². Therefore, polysomnography (PSG) can help identify a substantial number of breathing disorders that are associated with insomnia^23,24.

Women at the premenopausal and menopausal periods are more likely to develop sleep complaints and disorders than are women of a fertile age. Conjugated hormonal therapy (estrogen and progesterone) has been shown to efficiently improve general sleep complaints, as well as insomnia and OSAS²⁵. Benzodiazepine drugs are associated with reductions in wakefulness, reductions in the muscle tonus of airways and decreases in the ventilatory response to hypoxemia. Therefore, these drugs are considered to be inappropriate for treating these comorbidities. The use of CPAP or oral devices also interferes negatively in the quality of sleep, particularly during the adaptation phases.

Fibromyalgia

Patients with fibromyalgia present persistent tiredness and physical fatigue, associated with non-restoring sleep and diffuse muscle pain. Usually, these patients have the perception of a sleep disorder associated with fatigue. Pharmacological treatment mainly consists of tricycles antidepressants and cyclobenzaprine^26-32.

Circadian rhythm disorders

The delayed sleep phase syndrome is a circadian rhythm disorder, characterized by delays in falling asleep and in waking in the morning. This condition usually starts during childhood and adolescence, and is seldom misinterpreted as insomnia, particularly idiopathic insomnia^33-42.

Restless legs syndrome and periodic movements of limbs

The restless legs syndrome is characterized by sensory disorders that mainly affect the lower limbs, particularly before falling sleep, thus leading to difficulty in falling asleep. Periodic movements of limbs usually accompany the restless legs syndrome during sleep, leading to a fragmented sleeping pattern, which affects the quality of sleep. Periodic movements of the lower limbs can occur during sleep, independently of the existence of restless legs syndrome. In these cases, the repercussions on the sleep profile, with insomnia or daytime hypersomnolence, must be analyzed one by one, in each case⁴³.

Evaluation

When considering the etiopathogenesis of insomnia, it is important to highlight that insomnia may be of biological, environmental, behavioral or psychological nature. Likewise, the factors causing and perpetuating insomnia are interrelated with social, professional and family factors. Therefore, insomnia evaluations need to be broad-based, covering the patients' medical, psychological and social characteristics.

Medical evaluation (standard)

Evaluations on insomniac patients should begin by taking a rigorous and detailed medical history in which the history of symptoms is recorded, including the start of insomnia and its progression to a chronic condition, along with treatments already used and repercussions of the abnormal sleeping pattern during the day, such as somnolence, tiredness, fatigue and reduction of attention, concentration and memory⁴⁴.

Nighttime habits that should be recorded include: bedtime, activities in bed, turning off lights, time to fall asleep, time to waking up in the morning, time to getting up, sleep quality, number of awakenings, time spent awake during the night and reports of snoring and leg movements.

Day habits that should be recorded include: mealtimes, work and study periods, daytime naps, physical activity, smoking habit, alcohol intake, use of drugs and medications.

Bedroom conditions that should be recorded include: condition of the bed, mattress and pillows, number of people who sleep in the same bed, luminosity, noise, temperature and presence of a TV, computer or audio equipment in the bedroom.

Psychosocial evaluation (recommended)

This has the aim of investigating, in greater detail, the main precipitating and perpetuating factors of insomnia. A psychosocial evaluation must be carried out, taking into account the systemic focus, i.e. the insomnia symptoms are analyzed within the context of patients lives, and what these symptoms allow or cover^45-48.

Subsidiary examinations (recommended)

It is recommended that every insomniac patient should undergo complementary examinations when there is a suspicion of any systemic disease.

Questionnaires (recommended)

The use of a sleep diary, as well as other questionnaires, is fundamental to cognitive-behavioral therapy.

Polysomnography (recommended)

In order to investigate comorbidities such as obstructive sleep apnea, and for objective evaluation of sleep in cases of diagnosing inadequate perception, polysomnography is recommended as an auxiliary method for diagnosing of insomnia, whenever possible^49-52.

Treatment of primary insomnia

Cognitive-behavioral therapy (standard)

Today, cognitive-behavioral therapy (CBT) is a standard treatment for primary insomnia. It must not be used alone but, rather, in association with pharmacological therapy^53-58. CBT presents an advantage over pharmacological treatment: the low risk of side effects and the long-term maintenance of sleep pattern improvement. CBT has a limited and defined period of use, from four to eight sessions. It is a focal and direct type of therapy, in which patients play an active role and are co-responsible for their treatment. It can be undertaken individually or in groups^59-62.

The interventions are educational, behavioral and cognitive, and their theoretical basis is the behavioral model of insomnia proposed by Spielman. According to this model, three main factors can cause insomnia: predisposing, precipitating and perpetuating factors. The main CBT targets are the precipitating and perpetuating factors. The main behavioral and cognitive techniques are sleep hygiene, stimulus-control therapy, therapy of bedtime and sleeping time restriction, relaxation techniques, cognitive restructuring, paradoxical intention and cognitive therapy in sleep misperception disorders^63-67.

[1] Sleep hygiene: This is a psychoeducational intervention containing basic information on sleep habits and hygiene. It includes instructions for establishing regular sleeping times; going to bed only when feeling sleepy and not using the bed as a means of trying to sleep; not spending the day worrying about sleeping time; having control over time; avoiding the use of stimulants (coffee, cigarettes, drugs, black tea, Coca-Cola and chocolate); avoiding alcohol consumption before sleeping; and avoiding high liquid consumption before sleeping. It includes suggestions for dinner (light foods) not less than two hours before going to sleep, and for regular physical activity, preferably in the mornings. It evaluates the bedroom conditions: comfort, temperature, noise, and stresses the importance of having a bedroom that is silent, aired, clean and organized.

[2] Stimulus-control therapy: This aims towards educating insomniac patients on how to establish a more appropriate sleep-wakefulness rhythm and limit the time awake and the behavior allowed in the bedroom/bed. The main instructions for patients include the following items: to go to bed only when feeling sleepy; avoid any behavior other than sleep or sex in the bedroom/bed; if feeling incapable of sleeping, the patient should get up from bed and go to another place to do some relaxing activity in an environment with little light, and only go back to bed when feeling somnolence again; to keep to a fixed time for waking up, seven days per week, independently of the amount of sleep obtained; not to nap or to lie down during the day, to remove the TV, stereo and computer from the bedroom; not to eat, read, work, watch TV or use a computer in the bedroom/bed.

[3] Therapy of bedtime and sleeping time restriction: The aim of this therapy is to consolidate sleep through restricting the time that patients spend in bed to the average time they spend sleeping (i.e. the number of hours that they really spend sleeping), based on the information in the sleep diary. This technique creates a mild state of sleep deprivation that may cause daytime somnolence. However, at the same time, it provides sleep consolidation, thus making it easier to fall asleep, improving sleep efficiency and decreasing latency and variability between nights. It is not recommended to have less than four to five hours of sleep, and the necessary adjustments must be made in relation to time spent in bed, according to patients' responses to the proposed treatment. If patients reach 90% sleep efficiency, 15 minutes are added to the time allowed in bed and, if the efficiency is less than 85%, 15 minutes are taken away.

[4] Relaxation techniques: The aim of teaching relaxation techniques is to show patients how tense and hypervigilant they are during both day and night. Progressive relaxation is the treatment for insomnia that has been studied most. Patients are guided to tension and relax the major muscle groups sequentially, while observing the sensation of tension and relaxation.

[5] Cognitive restructuring: This is mainly based on cognitive symptoms that can cause or perpetuate insomnia. Cognitive restructuring works on concerns, thoughts, false attitudes, irrational beliefs about sleep and amplification of its consequences, false ideas about the causes of insomnia and disbelief about sleep induction practices and about their own capacity to sleep. The idea is to make patients abandon the symptoms of insomnia, by reminding them that the way in which events are thought about or judged determines the way that individuals feel about them.

[6] Paradoxical intention: This technique reduces the anticipatory anxiety associated with the fear of trying to fall sleep and not being capable of doing so, since insomniacs usually believe that they have lost their natural capacity to fall asleep. Patients are instructed to go to bed and stay awake and try not to sleep; this makes them more relaxed and not under obligation to fall asleep. They consequently fall asleep faster.

[7] Cognitive therapy for sleep misperception disorders: This therapy works on the relationship between patients' subjective perceptions of total sleeping time and the total sleeping time obtained through PSG. The intention of this approach is to give patients objective data on sleep efficiency obtained through PSG and make them comprehend that they are sleeping for longer than they think. This technique also makes them more relaxed regarding the quantity of sleep they consider necessary, and it enables them to fall asleep more easily when this new reality is acquired^51-52.

Pharmacological treatment

Pharmacological treatment consists of the use of hypnotic drugs that induce sleep, mainly because they act on the main inhibitory system of the central nervous system, the GABA system. Additionally, substances presenting sedative effects, such as antidepressants, may be used. More recently, medications that act on melatoninergic receptors have been considered promising as drugs for treating insomnia^68-72.

GABA-A receptor-selective agonist hypnotics

[1] Zolpidem (standard): This is the hypnotic drug used for treating insomnia. Zolpidem is an imidazopyridine that was developed in 1980 and has been used since 1990. It was the first selective α1 agonist. It is rapidly absorbed (in approximately one hour) and presents a short half-life of 2.5 hours. Its bioavailability ranges from 65% to 70%. Plasma concentration peaks occur 1.5 hours after drug intake. The therapeutic doses range from 5 to 10 mg, and the drug is metabolized in the liver and eliminated by the kidneys. In older people, and in cases of liver or kidney failure, the recommended dose is 5 mg⁷³. Although the use of sleep inductors for treating chronic insomnia is only recommended for one month, clinic trials have suggested that zolpidem remains effective and safe for a prolonged period of use, i.e. more than 35 days, in a 10 mg doses^74,75. The use of zolpidem reduces the cyclic alternating pattern types A1 and A2, even when in intermittent use^76,77.

Slow-release zolpidem (zolpidem MR, still not available in Brazil) is a new formulation used for patients with difficulty in maintaining their sleep. This formulation comprises pills with immediate release and pills for prolonged release, which maintains plasma concentrations for three to six hours after intake^78,79. Zolpidem can also be used intermittently over the long term, in accordance with patient needs, without rebound insomnia appearing^80-82.

[2] Zopiclone (recommended): This is a hypnotic drug that is recommended for treating insomnia. Zopiclone is a cyclopyrrolone that differs from zolpidem because of its longer half-life (5.3 hours) and its action on receptors containing the subunits α1 and α2. The recommended dose is 3.7 to 7.5 mg. A few side effects after withdrawal have been described; however, the residual effects on the following day may be attributed to its long half-life⁸³.

[3] Zaleplon (recommended) - not available: This is a pyrazolopyrimidine that links to the α1 receptor, thus making the drug a hypnotic agent that can be recommended for treating insomnia. The recommended dose is 10 mg and its half-life is approximately one hour. Because of these characteristics, zaleplon is indicated for sleep induction, while showing little effect on sleep maintenance. Zaleplon has already been in the Brazilian market, but it was withdrawn, which limits its use in this country ⁸⁴.

[4] Eszopiclone (recommended) - not available: This is a zopiclone isomer of cyclopyrrolone that is recommended for treating insomnia. Eszopiclone is rapidly absorbed and presents a relatively long half-life. The dose must be individualized, but ranges from 1 to 3 mg before going to bed^85-87.

[5] Indiplon (recommended) - not available: This is a pyrazolopyrimidine with similarities to zolpidem, zopiclone and zaleplon that is selective for receptors that contain a subunit α 1. It is a hypnotic drug recommended for treating insomnia. This drug has a formulation for immediate release (indiplon IR), which is indicated for initial insomnia, and a controlled formulation (indiplon MR), which lasts six to eight hours and is indicated for patients with complaints regarding sleep maintenance. The recommended dose ranges from 15 to 30 mg, taken just before going to bed⁸⁸.

Antidepressants

Sedative antidepressants (tricyclic, trazodone, doxepin and mirtazapine) are alternatives for pharmacological treatment of insomnia. However, there are no double-blind randomized studies proving the efficacy and safety of these agents. Some tricyclic antidepressants such as amitriptyline improve sleep continuity and efficiency and produce sedation during the day⁸⁹.

[1] Trazodone (recommended): Trazodone seems to be the second most commonly prescribed agent for treating insomnia. It belongs to the pharmacological group of serotonin reuptake inhibitors, and has antagonist action on the adrenergic receptors α 1, 5-HT1A and 5-HT2. Trazodone slightly suppresses REM sleep and improves sleep continuity. The recommended dose is 50 mg/day⁹⁰.

[2] Doxepin (recommended): This is a tricyclic antidepressant with antagonist effect on histamine H1/H2 receptors. It has been shown to be efficient if used in small doses (1 to 6 mg/night), for treating insomnia. It does not cause clinically significant residual or anti-cholinergic effects⁹¹.

[3] Mirtazapine (optional): This is an atypical antidepressant. Its mechanism of action depends on the increased noradrenergic activity provided by the antagonist effect of the drug on alpha-2a adrenergic receptors, and nonspecific blockage of serotonergic reuptake. Mirtazapine is a postsynaptic antagonist (blocker) of 5TH_2A and5TH _2C and 5-HT₃ with sedative and anxiolytic effects. Its histaminic H1 anti-receptor activity explains the strong sedative effect, and this is the antidepressant with the greatest sedative effect among the currently available drugs. The recommended doses range from 7 to 30 mg⁹².

[4] Amitriptyline (optional): This presents significant sedative effects due to its anticholinergic, anti-histaminic and anti-alpha₁ profile, and also due to the blockage of 5HT_2A and 5HT_2C receptors. The sedative effects are immediate, preceding the antidepressant effects, and decrease after a few weeks of treatment. The recommended dose ranges from 12.5 to 50 mg.

[5] Mianserin (optional): This is an atypical antidepressant with sedative effect that occurs through anti-histaminic 1 and 5HT_2A/2C receptor antagonistic effects. There are no long-term studies proving the efficacy and safety of mianserin for treating insomnia.

Valerian (optional)

Valerian (valepotriates) may be an option for treating insomnias and is used as an auxiliary medication when discontinuing benzodiazepine among chronic users. Some studies have reported that its mechanism of action is related to GABA. Valerian may act during sleep through other mechanisms, through MT1 and MT2 receptors (melatonin) and through the A1 adenosinergic receptor and some subtypes of 5-HT receptors⁹³.

Benzodiazepines (optional)

Benzodiazepines (BZDs) link nonspecifically to the alpha-1 and alpha-2 subunits of the GABA-A postsynaptic receptor and to any subunit of the gamma type. BZDs increase the affinity of the GABA-A postsynaptic receptor with endogenous GABA, and increase the intensity and duration of the inhibitory effects through boosting chloride channels. The link to the subunit alpha-1 is responsible for the hypnotic and cognitive effects of this drug, while the link to the subunit alpha-2 is responsible for the anxiolytic, anti-convulsion and muscle-relaxing effects. Withdrawal of BZDs may bring back the insomnia or cause rebound insomnia in patients, with worse symptoms than those presented before treatment. The presence of anxiety and the intensity of insomnia depend on patients' psychological profiles. Gradual and slow discontinuation of BZDs, with technical support, is recommended. The abstinence symptoms when discontinuing BZDs depend on a variety of factors. Many chronic users will be able to discontinue treatment successfully, provided that it is done with an appropriate technique^94-95.

Medication abuse often occurs among chronic users. Tolerance reflecting the progressive increase of BZD doses also depends on several factors. However, there are patients who do not develop tolerance after using BZDs for a long time. There are studies demonstrating the existence of a correlation between prolonged use of BZDs and increased risk of death. Amplification of obstructive ventilatory disorders during sleep, sedation, suppression of self-care, falls, confusion, amnesia and other possible drug-related symptoms may explain the increased mortality. BZDs are not indicated for individuals with drug addiction and alcohol abuse. Special care is necessary with elderly individuals, patients with kidney, liver and lung dysfunctions, and patients with psychiatric problems. BZDs may worsen the ventilatory disorders during sleep and are not indicated during pregnancy, or for individuals whose work may require prompt waking up and quick decision-making.

Among BZDs, clonazepam (optional), midazolam (optional) and estazolam (optional) can be used. The other BZDs are not recommended.

Melatonin receptor agonists (optional)

[1] Ramelteon: This is a new hypnotic drug that has been approved for treating chronic insomnia. It is an agonist with high selectivity for melatonin MT1 and MT2 receptors⁹⁶. The 8 mg recommended dose is rapidly absorbed (0.75-0.94 hour) and presents a half-life of 1.3 hours. Due to its short half-life, Ramelteon is indicated for treating initial insomnia^97-99. It is not efficient in maintaining sleep. Ramelteon is safe with regard to cognitive effects on the following day, and has not been shown to cause rebound insomnia when discontinued after chronic use. It has not shown any potential for abusive use or dependence^100-102.

[2] Agomelatine: This is an antidepressant with agonist action on melatonin receptors 1 and 2, and antagonist effect on serotoninergic 5-HT2C receptors. Because of its melatoninergic agonist effect, agomelatine may be a potential regulator of the circadian rhythm of depressed patients, thus leading to an added contribution for improving depression. Use of this medication at a dose of 25 to 50 mg has been shown to improve sleep quality, with reduced sleep latency, reduced awakening and increased slow-wave sleep^103,104.

Other pharmacological and new perspectives

Antihistamines are optional, while antipsychotics are not recommended.

New GABA agonists, like tiagabine and gaboxadol, are still not available in Brazil and are not recommended. These drugs are inhibitors of GABA reuptake, and are among the new perspectives for treating insomnia^105-110.

Insomnia during childhood

Classification (standard)

Insomnia during childhood is divided into behavioral insomnia, psychophysiological insomnia, insomnia in special populations, insomnia associated with clinical conditions and insomnia associated with the use of medications. The most common clinical causes of insomnia during childhood are pain or cramps, recurrent otitis, reflux, medications (stimulants or corticoids), night asthma attacks and airway obstructions.¹¹¹ The main type of insomnia in children is behavioral insomnia, but this is an exclusion diagnosis. During the first approach towards the child, the clinical causes of insomnia must always be eliminated.

[1] Behavioral insomnia during childhood: This occurs in 10 to 30% of preschool children. The International Classification of Sleep Disorders (ICSD-2005) defines children's difficulty in falling asleep and/or maintaining sleep as the essential characteristic of behavioral insomnia. These problems are associated with certain attitudes among children or their parents, and they can be classified into two types: association disorder and lack-of-limit disorder¹¹².

[2] Association disorder: There are certain conditions associated with the start of sleep that are necessary for children to fall asleep and for them to go back to bed after each awakening during the night. Positive associations are conditions that children can provide for themselves (pacifiers/dummies or teddy bears), while negative associations need assistance from someone else (baby bottles or rocking). The negative associations also include external stimuli (television or toys) or different situations (parents' bed or a car ride). When the condition associated with sleep is present, the child falls asleep rapidly. If the condition associated with sleep is not present, the child presents frequent and long-duration nighttime awakenings.

The diagnostic criteria consist of findings that falling asleep is a slow process that requires special conditions, and that associations with falling asleep are problematic and require much effort. When association elements are absent, the start of sleep is significantly delayed or sleep is fragmented. Nighttime awakening requires intervention so that these children can fall asleep again.

[3] Lack-of-limit disorder: This is presented as a refusal or delay in going to bed at the established time. On the other hand, delaying the time for going to sleep might include several requests (feeling thirsty, needing the bathroom or asking for one more goodnight kiss) or additional activities (watching TV or reading one more story). Once these children fall asleep, their sleep quality is normal and they tend to have few awakenings. However, children with lack-of-limit disorder normally have a shorter sleeping time (30 to 60 minutes).

The diagnostic criteria consist of difficulty in falling asleep or maintaining sleep; postponing or refusing to go to bed at the appropriate time or refusing to go back to bed after nighttime awakening; inability of the parents to establish appropriate sleep behavior for the child; lack of explanation for the sleep disorder in terms of other sleep disorders, clinical conditions, mental or neurological diseases, or use of medications.

[4] Insomnia associated with neurological and psychiatric conditions: Most syndromes with central nervous system dysfunction present some kind of sleep abnormality in their clinical presentation.

Diagnosis

Medical evaluation (standard) - The main questions in evaluating sleep disorders in pediatric cases include duration of sleep, sleep routines, events associated with sleep, daily behavior, humor and cognitive function. It is also essential to find out about significant events in the child's life, such as parents' divorce, changes of school or moving house, or events involving siblings. A sleep diary must be kept over a one or two-week period, and this is always useful for finding out about sleeping patterns and for following them over time. Parents are asked to write details about what time the child went to bed, how long the child took to fall asleep, the frequency and duration of nighttime awakening, the time and duration of daily naps, the time of waking up in the morning and the total duration of sleep¹¹³.

Polysomnography (optional): Polysomnographic testing and actigraphy are optional in diagnosing and treating insomnia in children. They are indicated only when necessary.

Consequences

Children with insufficient duration of sleep present fatigue and irritability. Parents may present negative feelings towards their children and, in order to avoid frustrations during sleeping times, they may postpone the sleep routine, which delays the start of sleep even more and prolongs the cycle of addiction.

Treatment

[1] Behavioral approach (standard): Time for going to sleep: The appropriate time for a child to go to sleep, from infancy to preschool age, should be between 7:00 and 8:30 pm. When bedtime is later than this, children get very tired, irritated and have difficulty in sleeping. The time for going to sleep should not vary between weekdays and weekends. Daytime naps are essential for the child. The need for daytime naps tends to disappear between the ages of three and six years¹¹⁴.

Bedtime routine: Establishing a routine is very important for children's lives. The bedtime routine can be started at three months of age, through establishing a constant time for going to sleep. Any electronic equipment near the child must be turned off before starting the ritual for going to sleep.

Falling asleep independently: Children with insomnia are incapable of falling asleep without their parents' intervention, such as rocking or feeding. Children must be put in the cradle or go to bed when they are sleepy, but still awake, and then they must fall asleep independently. There are several methods that help children fall asleep by themselves, for example, "extinction" alone, gradual "extinction", positive routines, brief visits and weaning children from their parents' presence¹¹⁵.

"Extinction" alone consists of leaving the child cry until falling sleep. "Extinction" is based in the theory that behavior that is reinforced increases in frequency, while behavior that is ignored will disappear with time. If parents are regular and do not attend their child's calls, in general, the child will be able to sleep alone after three to five nights. Gradual extinction is an alternative for parents who do not want to use extinction alone. This method consists of putting the sleepy, but awake, child in the cradle and then ignoring the calls or crying for gradually increasing periods. When observing the child at night, the visit must be short and uniform, without lights and without speaking loudly or touching the child.

The gradual reduction of the mother's presence includes an initial phase in which physical contact is reduced at bedtime. Mothers who feed their children at bedtime must do this activity earlier in another room and only rock the child to sleep. After achieved success with this strategy, the child must be put in the cradle and the mother must caress the child's head or arm until the child falls asleep. In the second step, the mother's presence in the bedroom must be reduced. The third step consists of increasing the time between each visit. Positive routines aim to create a pleasant and positive environment not only for the child but also for the parents.

[2] Pharmacological treatment (optional): Pharmacological treatment must be considered as the last option. Most medications prescribed for insomnia among adults are not recommended for children. However, in specific cases, generally when there is an underlying neurological or psychiatric disease, BDZs can be used (clonazepam, clobazam, midazolam or diazepam), as well as zolpidem, zopiclone, chloral hydrate, levomepromazine, promethazine, carbamazepine, clonidine, risperidone and melatonin, always considering the age of the child and the risk/benefit associated with the use of these drugs¹¹⁶.

Received 2 March 2010

Received in final form 11 March 2010

Accepted 18 March 2010

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Publication Dates

• Publication in this collection
  11 Aug 2010
• Date of issue
  Aug 2010

History

• Accepted
  18 Mar 2010
• Reviewed
  11 Mar 2010
• Received
  02 Mar 2010