Nocturnal visual hallucinations in patients with disorders of arousal: a novel behavioral and EEG pattern.

AIM: To investigate clinical and video-polysomnography (VPSG) findings of hallucinatory experiences in patients suffering from disorders of arousal (DOA) in the absence of other pathologies. METHODS: The authors retrospectively reviewed the records of 370 adults with DOA. Thirty (8.1%) patients concomitantly reported complex nocturnal visual hallucinations. VPSG recordings were scrutinized, and motor behavioral and electroencephalogram (EEG) patterns were classified according to previous descriptions of DOA. RESULTS: Thirty DOA patients reported seeing images of objects, people, and animals; either distorted, static, or mobile. The images disappeared with increased illumination in 80% of patients, and 23.3% reported preceding dream imagery. In addition to the classical DOA patterns on VPSG, a distinct pattern of behavioral and EEG manifestation associated with complex hallucinatory episodes was identified in 16 (53.3%) DOA patients. This consisted of low-voltage mixed-frequency EEG activity before eye opening that persisted while patients were observed staring or visually tracking before the onset of motor behavior. CONCLUSION: A novel, distinct behavioral and EEG pattern in patients with DOA and history of reported complex nocturnal visual hallucinations was identified. This may represent a unique phenotype of dissociation between sleep states that merits further investigation.

Sodium glucose-linked transport protein 2 inhibitors: An overview of genitourinary and perioperative implications.

Sodium glucose-linked transport protein 2 inhibitors are relatively novel drugs, used for the treatment of type 2 diabetes mellitus. Their use since Pharmaceutical Benefits Scheme approval in Australia has increased drastically, possibly due to the low risk of hypoglycemic events and their advertised cardiovascular mortality benefits. However, as with any novel drug, adverse effects regarding their use require medical practitioner awareness for optimal patient outcomes. This paper aims to cover the major urological implications, including those pertinent perioperatively, that concern this class of drugs. There is a clear risk of developing genital mycotic infections with the use of sodium glucose-linked transport protein 2 inhibitors, including serious infections such as Fournier's gangrene. Evidence for developing urinary tract infections has been mixed. Sodium glucose-linked transport protein 2 inhibitor-induced lower urinary tract symptoms may have impacts on quality of life via pollakiuria and nocturia, of which there are increased reports. Perioperative use increases the risk of euglycemic diabetic ketoacidosis. It is recommended that sodium glucose-linked transport protein 2 inhibitors be ceased perioperatively.

Co-activation of rhythms during alpha band oscillations as an interictal biomarker of exploding head syndrome.

BACKGROUND: Exploding head syndrome is a rarely reported benign sensory parasomnia that may nonetheless have significant impact on patients' quality of life and their perceived well-being. To date, the mechanisms underlying attacks, characterised by a painless perception of abrupt, loud noises at transitional sleep-wake or wake-sleep states, are by and large unclear. METHODS AND RESULTS: In order to address the current gap in the knowledge of potential underlying pathophysiology, a retrospective case-control study of polysomnographic recordings of patients presenting to a tertiary sleep disorders clinic with exploding head syndrome was conducted. Interictal (non-attack associated) electroencephalographic biomarkers were investigated by performing macrostructural and event-related dynamic spectral analyses of the whole-night EEG. In patients with exploding head syndrome, additional oscillatory activity was recorded during wakefulness and at sleep/wake periods. This activity differed in its frequency, topography and source from the alpha rhythm that it accompanied. CONCLUSION: Based on these preliminary findings, we hypothesise that at times of sleep-wake transition in patients with exploding head syndrome, aberrant attentional processing may lead to amplification and modulation of external sensory stimuli.

Video polysomnographic findings in non-rapid eye movement parasomnia.

Although video polysomnography (vPSG) is not routinely recommended for the evaluation of typical cases of non-rapid eye movement (NREM) parasomnias, it can aid diagnosis of unusual cases, other sleep disorders and complicated cases with REM behaviour disorder (RBD), and in differentiating parasomnias from epilepsy. In this study, we aimed to assess vPSG findings in consecutive patients with a clinical diagnosis of NREM-parasomnia covering the whole phenotypic spectrum. Five hundred and twelve patients with a final diagnosis of NREM parasomnia who had undergone vPSG were retrospectively identified. vPSGs were analysed for features of NREM parasomnia and for the presence of other sleep disorders. Two hundred and six (40.0%) patients were clinically diagnosed with sleepwalking, 72 (14.1%) with sleep terrors, 39 (7.6%) with confusional arousals, 15 (2.9%) with sexsomnia, seven (1.4%) with sleep-related eating disorder, 122 (23.8%) with mixed phenotype, and 51 (10.0%) with parasomnia overlap disorder (POD). The vPSG supported the diagnosis of NREM parasomnia in 64.4% of the patients and of POD in 98%. In 28.9% of the patients, obstructive sleep apnea (OSA) or/and periodic limb movements during sleep (PLMS) were identified, most commonly in older, male, sleepy and obese patients. vPSG has a high diagnostic yield in patients with NREM parasomnia and should be routinely performed when there is diagnostic doubt, or in patients where there is a suspicion of OSA and PLMS.

Maternal outcomes following massive obstetric haemorrhage in an inner-city maternity unit.

This retrospective study evaluates the effects of a massive postpartum haemorrhage (PPH) on maternal outcomes in an inner-city London hospital. One hundred and eighty-four cases of a massive primary PPH (>2000 mL) were identified over a seven-year period. A sub-group analysis was performed to assess whether 2000-3000 mL blood loss (134 cases) was associated with specific maternal characteristics or reduced adverse outcomes compared with >3000 mL blood loss (50 cases). Bakri balloon tamponade (BBT) was the most frequent form of surgical management in both groups (21 vs. 46%), followed by compression sutures (16.4 vs. 24%), the 'uterine sandwich' technique (6.7 vs. 14%) and the hysterectomy (0 vs. 4%). There were significant differences between these groups in placenta praevia as the cause of blood loss (8 vs. 22%, p = .01), length of stay (4.6 vs. 5.9 d, p = .02), use of BBT (p = <.01) and hysterectomy (p = .03). PPH is associated with premature maternal morbidity and mortality. The incidence is increasing in high income countries despite various guidelines, skills training and identification of risk factors. A prediction and assessment of blood loss remain the very cornerstone for a prompt, effective management. Our study shows that the morbidity is clearly related to the amount of blood loss and highlights the existing variable practices for the management of PPH. Impact statement What is already known on this subject? A postpartum haemorrhage (PPH) remains a common cause of maternal morbidity and mortality. Massive PPH (>2000 mL) rates continue to rise in developed countries. The management of PPH includes the medical treatment followed by surgical methods including the Bakri balloon tamponade (BBT), compression sutures or a hysterectomy. What do the results of this study add? This retrospective study evaluates the effects of a massive PPH (blood loss >2000 mL) on maternal outcomes. One hundred and eighty-four cases of a massive PPH were identified over a seven-year period. Sub-group analysis was performed to assess whether a 2000-3000 mL blood loss was associated with specific maternal characteristics and differences in obstetric practice compared with a >3000 mL blood loss. There were significant differences between these groups in placenta praevia, as the cause of blood loss, the length of stay, the use of BBT and the hysterectomy rates. What are the implications of these findings for clinical practice and/or further research? An early identification of the risk factors of a massive PPH is essential to improve maternal outcomes and is an important part of the antenatal, intrapartum and postpartum period. The prediction and assessment of blood loss remain key for a prompt, effective management. The amount of blood loss is related to adverse maternal outcomes and the management techniques applied. BBT has an essential role to play and should be included as part of the core training in the management of a PPH.

Interpretation of Serum Gonadotropin Levels in Hyperprolactinaemia.

BACKGROUND/AIMS: Hyperprolactinaemia is a common cause of amenorrhoea due to hypogonadotropic hypogonadism. Prolactin is hypothesised to impede the reproductive axis through an inhibitory action at the hypothalamus. However, limited data exist to aid the interpretation of serum gonadotropins in the context of hyperprolactinaemia. METHODS: Serum gonadotropin values were reviewed in 243 patients with elevated serum monomeric prolactin due to discrete aetiologies at a tertiary reproductive endocrine centre between 2012 and 2015. The cause of hyperprolactinaemia was categorised by an experienced endocrinologist/pituitary multidisciplinary team, unless superseded by histology. The most frequently encountered diagnoses were microprolactinoma (n = 88), macroprolactinoma (n = 46), non-functioning pituitary adenoma (NFPA) (n = 72), drug-induced hyperprolactinaemia (n = 22) and polycystic ovarian syndrome (PCOS) (n = 15). RESULTS: In patients with prolactinoma and modestly raised serum prolactin levels (< 4,000 mU/L), increasingly FSH-predominant gonadotropin values were observed with rising prolactin level, consistent with a progressive reduction in hypothalamic gonadotropin-releasing hormone (GnRH) pulsatility. Patients with prolactinoma and higher prolactin values (> 4,000 mU/L) were more likely to have a reduction in serum levels of both FSH and LH, consistent with direct pituitary gonadotrope dysfunction. Patients with macroadenoma and extremes of serum gonadotropin values (either serum FSH or LH > 8 IU/L) were more likely to have NFPA than prolactinoma. Patients with PCOS and hyperprolactinaemia had LH-predominant secretion in keeping with increased GnRH pulsatility despite a raised prolactin level. CONCLUSION: The pattern of gonadotropin secretion in patients with hyperprolactinaemia reflects the underlying aetiology.

Effectiveness and side-effect profile of stimulant therapy as monotherapy and in combination in the central hypersomnias in clinical practice.

Effectiveness and side-effect profile data on pharmacotherapy for daytime sleepiness in central hypersomnias are based largely upon randomized controlled trials. Evidence regarding the use of combination therapy is scant. The aim of this study was to examine the effectiveness and occurrence of drug-related side effects of these drugs in routine clinical practice. Adult patients diagnosed with a central hypersomnia during a 54-month period at a tertiary sleep disorders centre were identified retrospectively. Side effects were recorded at every follow-up visit. A total of 126 patients, with 3275 patient-months of drug exposure, were categorized into narcolepsy type 1 (n = 70), narcolepsy type 2 (n = 47) and idiopathic hypersomnia (n = 9). Modafinil was the most common drug used as a first-line treatment (93%) and in combination therapy (70%). Thirty-nine per cent of the patients demonstrated a complete, 25% partial and 36% a poor response to treatment. Combination treatment improved daytime sleepiness in 55% of the patients with residual symptoms despite monotherapy. Sixty per cent of patients reported side effects, and 30% reported treatment-limiting side effects. Drugs had similar side-effect incidence (P = 0.363) and their side-effect profile met those reported in the literature. Twenty-seven per cent of the patients received combination treatment and had fewer side effects compared to monotherapy (29.4% versus 60%, respectively, P = 0.001). Monotherapy appears to achieve satisfactory symptom control in most patients with central hypersomnia, but significant side effects are common. Combination therapy appears to be a useful and safe option in patients with refractory symptoms.

A second dose of kisspeptin-54 improves oocyte maturation in women at high risk of ovarian hyperstimulation syndrome: a Phase 2 randomized controlled trial.

STUDY QUESTION: Can increasing the duration of LH-exposure with a second dose of kisspeptin-54 improve oocyte maturation in women at high risk of ovarian hyperstimulation syndrome (OHSS)? SUMMARY ANSWER: A second dose of kisspeptin-54 at 10 h following the first improves oocyte yield in women at high risk of OHSS. WHAT IS KNOWN ALREADY: Kisspeptin acts at the hypothalamus to stimulate the release of an endogenous pool of GnRH from the hypothalamus. We have previously reported that a single dose of kisspeptin-54 results in an LH-surge of ~12-14 h duration, which safely triggers oocyte maturation in women at high risk of OHSS. STUDY DESIGN, SIZE, DURATION: Phase-2 randomized placebo-controlled trial of 62 women at high risk of OHSS recruited between August 2015 and May 2016. Following controlled ovarian stimulation, all patients (n = 62) received a subcutaneous injection of kisspeptin-54 (9.6 nmol/kg) 36 h prior to oocyte retrieval. Patients were randomized 1:1 to receive either a second dose of kisspeptin-54 (D; Double, n = 31), or saline (S; Single, n = 31) 10 h thereafter. Patients, embryologists, and IVF clinicians remained blinded to the dosing allocation. PARTICIPANTS/MATERIALS, SETTING, METHODS: Study participants: Sixty-two women aged 18-34 years at high risk of OHSS (antral follicle count ≥23 or anti-Mullerian hormone level ≥40 pmol/L). Setting: Single centre study carried out at Hammersmith Hospital IVF unit, London, UK. Primary outcome: Proportion of patients achieving an oocyte yield (percentage of mature oocytes retrieved from follicles ≥14 mm on morning of first kisspeptin-54 trigger administration) of at least 60%. Secondary outcomes: Reproductive hormone levels, implantation rate and OHSS occurrence. MAIN RESULTS AND THE ROLE OF CHANCE: A second dose of kisspeptin-54 at 10 h following the first induced further LH-secretion at 4 h after administration. A higher proportion of patients achieved an oocyte yield ≥60% following a second dose of kisspeptin-54 (Single: 14/31, 45%, Double: 21/31, 71%; absolute difference +26%, CI 2-50%, P = 0.042). Patients receiving two doses of kisspeptin-54 had a variable LH-response following the second kisspeptin dose, which appeared to be dependent on the LH-response following the first kisspeptin injection. Patients who had a lower LH-rise following the first dose of kisspeptin had a more substantial 'rescue' LH-response following the second dose of kisspeptin. The variable LH-response following the second dose of kisspeptin resulted in a greater proportion of patients achieving an oocyte yield ≥60%, but without also increasing the frequency of ovarian over-response and moderate OHSS (Single: 1/31, 3.2%, Double: 0/31, 0%). LIMITATIONS, REASONS FOR CAUTION: Further studies are warranted to directly compare kisspeptin-54 to more established triggers of oocyte maturation. WIDER IMPLICATIONS OF THE FINDINGS: Triggering final oocyte maturation with kisspeptin is a novel therapeutic option to enable the use of fresh embryo transfer even in the woman at high risk of OHSS. STUDY FUNDING/COMPETING INTEREST(S): The study was designed, conducted, analysed and reported entirely by the authors. The Medical Research Council (MRC), Wellcome Trust & National Institute of Health Research (NIHR) provided research funding to carry out the studies. There are no competing interests to declare. TRIAL REGISTRATION NUMBER: Clinicaltrial.gov identifier NCT01667406. TRIAL REGISTRATION DATE: 8 August 2012. DATE OF FIRST PATIENT'S ENROLMENT: 10 August 2015.

Migraine with brainstem aura presenting as recurrent hypersomnia (Kleine-Levin syndrome).

Recurrent hypersomnia, or Kleine-Levin syndrome, is rare and frequently causes substantial diagnostic anxiety and delay. Patients often undergo multiple investigations to rule out other causes of encephalopathy. The treatment options are unsatisfactory. Migraine with brainstem aura has not previously been widely considered in the medical literature as a differential diagnosis. We describe two patients referred to a tertiary sleep neurology service with a putative diagnosis of Kleine-Levin syndrome. Each described attacks of hypersomnia with elements of migraine with brainstem aura, in addition to having a history of migraine with aura. Simple acute migraine treatment clearly attenuated further attacks. These cases generate discussion as to the common features and potential mechanisms underlying both disorders. Furthermore, they highlight a hitherto underexplored alternative diagnosis of Kleine-Levin syndrome. This provides scope for offering established and effective migraine treatment options to patients who with a potential misdiagnosis of Kleine-Levin syndrome, providing scope for offering established and effective migraine treatment to some patients originally diagnosed with a rare condition for which there is no current consistently effective therapeutic options.

Headache, drugs and sleep.

BACKGROUND: Headache and sleep mechanisms share multiple levels of physiological interaction. Pharmacological treatment of headache syndromes may be associated with a broad range of sleep disturbances, either as a direct result of the pharmacology of the drug used, or by unmasking physiological alterations in sleep propensity seen as part of the headache symptom complex. PURPOSE: This review summarises known sleep and circadian effects of various drugs commonly used in the management of headache disorders, with particular attention paid to abnormal sleep function emerging as a result of treatment. METHOD: Literature searches were performed using MEDLINE, PubMed, and the Cochrane database using search terms and strings relating to generic drug names of commonly used compounds in the treatment of headache and their effect on sleep in humans with review of additional pre-clinical evidence where theoretically appropriate. CONCLUSIONS: Medications used to treat headache disorders may have a considerable impact on sleep physiology. However, greater attention is needed to characterise the direction of the changes of these effects on sleep, particularly to avoid exacerbating detrimental sleep complaints, but also to potentially capitalise on homeostatically useful properties of sleep which may reduce the individual burden of headache disorders on patients.

Out of synch with society: an update on delayed sleep phase disorder.

PURPOSE OF REVIEW: Delayed sleep phase disorder is the most common of the circadian rhythm sleep disorders. Its treatment involves exploiting the intrinsic biological properties of the circadian pacemaker to advance biological rhythms, most notably the sleep-wake cycle, to a time which affords the individual an appropriate sleep opportunity compatible with normal societal functioning. This review highlights several new studies published in the last 18 months concerning sleep and circadian physiology relevant to the disorder and its management. RECENT FINDINGS: In addition to new information regarding the epidemiology and associations of the disorder, the pathophysiological importance of light exposure across the entire day, with special relevance to the phase-delaying effects of artificial evening light, is being unravelled. Furthermore, disorder-specific differences in period length and sleep homeostasis are being considered as pathophysiological contributors to delayed sleep phase disorder. The molecular effects of chronic sleep deprivation and circadian misalignment are currently being explored as potential mechanistic markers of the deleterious health consequences associated with these states. SUMMARY: Advances in our understanding of the dynamics of circadian physiology, sleep-wake regulation and the deleterious effects of misalignment and sleep deprivation, are spurring on efforts to find optimal treatment paradigms for patients presenting to sleep clinics with delayed sleep phase disorder.

Comorbidities of migraine: Sleep disorders.

Sleep disorders are commonly found as comorbid problems in patients with migraine. Indeed, there are likely to be numerous levels of interaction between migraine and sleep, including physiological, pathological, and pharmacological. Of note, the presence of sleep disorders may be a modifiable factor in the trajectory of migraine, and therefore active enquiry to elicit their presence, and manage them appropriately, could be an important component in the holistic care of patients with migraine. This review attempts to provide an outline of what is known about these relationships and highlight where relevant which facets could be exploited for therapeutic gain.

PSMA-PET detected port site recurrence of prostate cancer following minimally invasive radical prostatectomy and utilisation of hookwire localisation for excision.

Biochemical recurrence following prostate cancer treatment is well-known, with predictable sites typically observed in the prostate bed, lymph nodes, or skeleton. The emergence of PSMA-PET scans has revealed the potential for early recurrence in non-conventional sites, including port site metastases. Our report presents a rare case of abdominal wall metastasis detected 97 months post-prostatectomy. The excision of this subcutaneous lesion using image-guided hookwire techniques showed promise in minimising morbidity while providing successful oncologic outcomes. Further investigation is needed to establish the efficacy of PSMA-PET-guided interventions on long-term patient outcomes in treating prostate cancer port site metastases.

Primary Ewing sarcoma of the kidney presenting as haematuria in a pregnant woman - A case report highlighting the diagnostic and therapeutic dilemmas of the condition in pregnancy.

Primary Ewing sarcoma of the kidney is an extremely rare yet aggressive tumour. We present a 31-year-old pregnant female who presented to the emergency department with macroscopic haematuria and an ultrasound scan demonstrating a right renal mass. On magnetic resonance imaging, the lesion had features concerning for malignancy. She underwent a radical nephrectomy and was commenced on a personally tailored chemotherapy regime designed to permit healthy delivery of her baby while adequately treating her disease. This highlights an extremely rare differential for a renal mass which should be considered in rapidly growing renal tumours of a young patient.

Prevalence and utility of overnight pulse oximetry as a screening tool for obstructive sleep apnoea in newly diagnosed idiopathic intracranial hypertension.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a condition of raised intracranial pressure (ICP). Obstructive sleep apnoea (OSA) has been shown to cause episodic rises in ICP and is frequently reported in patients with IIH. The aim of this study is to identify the prevalence of OSA in a cohort of IIH patients. METHODS: We conducted a retrospective case notes review as part of a service evaluation of newly diagnosed IIH patients who were all referred for OSA screening with overnight pulse oximetry. The 3% oxygen desaturation index (3% ODI) was used to evaluate the presence and severity of OSA. The clinical outcomes of patients who received continuous positive airway pressure (CPAP) therapy as treatment for OSA were reviewed. RESULTS: In our cohort of newly diagnosed IIH patients, the yield of overnight pulse oximetry as a screening tool was 48.6% for OSA and 15.3% for moderate to severe OSA. We found that age (p = 0.0008), BMI (p < 0.0001), vitamin B12 (p = 0.0183), and a higher Epworth Sleep Score (p = 0.0269) correlated with more severe OSA. Eleven (10%) patients had CPAP therapy and those with good adherence alongside weight loss or medical therapy found improvements in symptoms of raised ICP. CONCLUSION: We report the largest series of consecutive IIH patients screened for OSA using overnight pulse oximetry. The high rate of OSA highlights a potential role for the recognition and management of OSA in the IIH patient cohort. Further studies on the potential contribution of OSA as a cause of raised ICP in the IIH cohort is warranted.

Digital health coaching to improve patient preparedness for elective lower limb arthroplasty: a quality improvement project.

Major surgery carries high risks with comorbidities, frailty and health risk behaviours meaning patients are often unprepared for the physiological insult. Since 2018, the Prepwell programme at South Tees Hospitals NHS Foundation Trust has supported patients to improve their preoperative health and fitness. In April 2020, the face-to-face service was suspended due to the pandemic, leading to the team implementing a three-tiered remote digital support pathway, including digital health coaching via a mobile phone application. METHODS: Patients scheduled for elective lower limb arthroplasty were offered 8 weeks of digital health coaching preoperatively. Following consent, participants were assigned a personal health coach to set individual behaviour change goals supported by online resources, alongside a digitally delivered exercise programme. Participants completed self-assessment questionnaires at Entry to, and Exit from, the programme, with outcome data collected 21 days postoperatively. The primary outcome was the change in Patient Activation Measure (PAM). RESULTS: Fifty-seven of 189 patients (30.2%) consented to referral for digital health coaching. Forty participants completed the 8-week programme. Median PAM increased from 58.1 to 67.8 (p=0.002). Thirty-five per cent of participants were in a non-activated PAM level at Entry, reducing to 15% at Exit with no participants in PAM level 1 at completion. Seventy-one percent of non-activated participants improved their PAM by one level or more, compared with 45% for the whole cohort. Median LOS was 2 days, 1 day less than the Trust's arthroplasty patient population during the study period (unadjusted comparison). CONCLUSIONS: Digital health coaching was successfully implemented for patients awaiting elective lower limb arthroplasty. We observed significant improvements in participants' PAM scores after the programme, with the largest increase in participants with lower activation scores at Entry. Further study is needed to confirm the effects of digital health coaching in this and other perioperative groups.

Group Cognitive Behavioural Therapy for Non-Rapid Eye Movement Parasomnias: Long-Term Outcomes and Impact of COVID-19 Lockdown.

Prior to the COVID-19 pandemic, we demonstrated the efficacy of a novel Cognitive Behavioural Therapy programme for the treatment of Non-Rapid Eye Movement Parasomnias (CBT-NREMP) in reducing NREM parasomnia events, insomnia and associated mood severities. Given the increased prevalence and worsening of sleep and affective disorders during the pandemic, we examined the sustainability of CBT-NREMP following the U.K.'s longest COVID-19 lockdown (6 January 2021-19 July 2021) by repeating the investigations via a mail survey in the same 46 patient cohort, of which 12 responded. The survey included validated clinical questionnaires relating to NREM parasomnia (Paris Arousal Disorder Severity Scale), insomnia (Insomnia Severity Index) and anxiety and depression (Hospital Anxiety and Depression Scale). Patients also completed a targeted questionnaire (i.e., Impact of COVID-19 Lockdown Questionnaire, ICLQ) to assess the impact of COVID-19 lockdown on NREM parasomnia severity, mental health, general well-being and lifestyle. Clinical measures of NREM parasomnia, insomnia, anxiety and depression remained stable, with no significant changes demonstrated in questionnaire scores by comparison to the previous investigatory period prior to the COVID-19 pandemic: p (ISI) = 1.0; p (HADS) = 0.816; p (PADSS) = 0.194. These findings support the longitudinal effectiveness of CBT-NREMP for up to three years following the clinical intervention, and despite of the COVID-19 pandemic.

Profile of sleep disturbances in patients with recurrent depressive disorder or bipolar affective disorder in a tertiary sleep disorders service.

Bidirectional relationship between sleep disturbances and affective disorders is increasingly recognised, but its underlying mechanisms are far from clear, and there is a scarcity of studies that report on sleep disturbances in recurrent depressive disorder (RDD) and bipolar affective disorder (BPAD). To address this, we conducted a retrospective study of polysomnographic and clinical records of patients presenting to a tertiary sleep disorders clinic with affective disorders. Sixty-three BPAD patients (32 female; mean age ± S.D.: 41.8 ± 12.4 years) and 126 age- and gender-matched RDD patients (62 female; 41.5 ± 12.8) were studied. Whilst no significant differences were observed in sleep macrostructure parameters between BPAD and RDD patients, major differences were observed in comorbid sleep and physical disorders, both of which were higher in BPAD patients. Two most prevalent sleep disorders, namely obstructive sleep apnoea (OSA) (BPAD 50.8.0% vs RDD 29.3%, P = 0.006) and insomnia (BPAD 34.9% vs RDD 15.0%, P = 0.005) were found to be strongly linked with BPAD. In summary, in our tertiary sleep clinic cohort, no overt differences in the sleep macrostructure between BPAD and RDD patients were demonstrated. However, OSA and insomnia, two most prevalent sleep disorders, were found significantly more prevalent in patients with BPAD, by comparison to RDD patients. Also, BPAD patients presented with significantly more severe OSA, and with higher overall physical co-morbidity. Thus, our findings suggest an unmet/hidden need for earlier diagnosis of those with BPAD.