Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic encephalopathic state, manifesting clinical symptoms of headache, altered consciousness, visual disturbances, and seizures. Although several diseases have been identified as causative of PRES, the underlying mechanism remains unclear. Song et al recently published “Posterior reversible encephalopathy syndrome (PRES) in a patient with metastatic breast cancer: A case report“ in the World Journal of Clinical Cases, highlighting and discussing the role of hypercalcemia in PRES as related to uncontrolled hypertension. To build upon this case description, we provide further insight into the possible underlying mechanisms of PRES through this commentary.

Background: Stroke patients have sleep-wake disorders, mostly in form of insomnia, excessive daytime sleepiness/fatigue, or hypersomnia (increased sleep needs). Objective: The aim of this study was to analyze types of sleep disorder (SD) and their frequency in patients with sleep apnea and acute stroke in relation to the type of stroke and side of lesion. Methods: The study analyzed 110 patients with sleep apnea and acute stroke hospitalized in the Clinic of Neurology, University Clinical Centre Tuzla. Acute stroke has been verified either by computerized tomography or magnetic resonance imaging of the brain. SD was verified according to the Berlin Questionnaire Test, The Epworth Sleepiness Scale, The Stanford Sleepiness Scale and the General sleep questionnaire. Strokes were divided by: a) type, into hemorrhagic and ischemic, and b) the localization of the stroke, to right and left cerebral hemispheres. Results: Of the total number of respondents, all had some sleep disorder. 20% of respondents had severe level of SD, 35.4% moderate, 37.3% moderate- severe and 7.3% mild problems. There were no statistically significant differences in the frequency of SD among patients with ischemic and hemorrhagic stroke (p = 0.58). In relation to the side of lesion, there was more patient with SD and stroke in the both sides, but there were no statistically significant differences (X2=1.98, p=0.161). According Epworth Sleepiness Scale, Stanford Sleepiness Scale and Berlin Questionnaire test snoring was present in 81% and daytime sleepiness in all patients. Conclusion: SD as a neuropsychological disorder has a significant incidence in the acute phase of stroke in patients with sleep apnea. Sleep disorder is more common in ischemic stroke and stroke in the both hemisphere, but it is not statistically significant difference. Daytime sleepiness, fatigue and snoring are the most common sleep problems in patients with acute stroke and apnea, but it is not statistically significant.

Background: More than 50% of stroke patients have sleep-disordered breathing (SDB), mostly in the form of obstructive sleep apnea (OSA). SDB represents both a risk factor and a consequence of stroke. The presence of SDB has been linked with the poorer long-term outcome and increased long-term stroke mortality. About 20 to 40% of stroke patients have sleep-wake disorders (SWD), mostly in form of insomnia, excessive daytime sleepiness/fatigue, or hypersomnia (increased sleep needs). Objective: The aim of this study was to analyze the frequency of risk factors in patients with acute stroke and sleep apnea. Methods: The study included patients without cognitive impairment or with mild cognitive impairment. The diagnosis of apnea syndrome was made on the basis of the Snoring and Apnea Syndrome Questionnaire, the Epworth Sleep Scale, the Berlin Questionnaire, the Stanford Sleepiness Scale, and the General Sleep Questionnaire. The severity of stroke was assessed by the National Institutes of Health Stroke Scale and the Rankin Disability Scale. Patients with a Glasgow score <8 on the day of neuropsychiatric examination were excluded from the study, as well as patients with epileptic seizures at the onset of stroke, with aphasia, with Mini - mental test <23, with verified previous dementia / cognitive impairment. Results: There is no statistically significant difference in the age of men and women, both with apnea and without apnea. In patients with apnea, heart disease was in the first place 91.8%, followed by hypertension 86.4%, Body mass index 79.1%, hyperlipidemia 50%, smoking 38.2 % and diabetes mellitus 20.9%. Hypertension was the most common risk factor in patients without apnea 83.6%, followed by heart disease 81.0%, Body mass index 60.9%, hyperlipidemia 48.21%, smoking 28.2 % and diabetes mellitus 20%. Conclusion: Heart diseases, hypertension and body mass index are significantly more frequent in patients with than in patients without sleep apnea.

Background: Sleep is a complex process involving the interactions of several brain regions, which play a key role in regulating the sleep process, particularly the brainstem, thalamus, and anterior basal brain regions. The process of sleep is accompanied by a change in body functions, as well as a change in cerebral electrical activity, which is under the control of the autonomic nervous system. Objective: The aim of the study was to analyze the frequency of stroke recurrence and disability of patients with stroke and apnea. Methods: It was analyzed 110 acute stroke patients with sleep apnea. All patients were evaluated with: Glasgow scale, The American National Institutes of Health Scale Assessment, Mini Mental Test, The Sleep and snoring Questionnaire Test, The Berlin Questionnaire Test, The Epworth Sleepiness Scale, The Stanford Sleepiness Scale, and The general sleep questionnaire. Results: The largest number of patients with apnea on admission had a degree of disability of 4, and on discharge of 1. There was a statistically significant difference between the mean values of incapacity for admission and discharge. The student’s t - test did not determine a statistically significant difference in disability according to the Rankin scale between patients with and without apnea at admission (t = 0.059, p = 0.95) and discharge (t = 0.71, p = 0.48). According to the NIHS scale, patients of both sexes with apnea had a neurological deficit of 7.55 ± 5.22 on admission and 7.1 ± 4.3 without apnea. Statistically significant difference was not found on the neurological deficit of both sexes, with and without apnea, at admission and discharge. With apnea, there were 13 relapses of stroke during one year, and without apnea in only 3 patients. Conclusion: Patients with acute stroke have a significantly higher correlation rate according to sleep apnea. There is no significant correlation in the degree of disability between patients with and without apnea.

An Retraction to this paper has been published: 10.1007/s00198-021-06031-0

Dear Co-editors-in-Chief Kanis and Cosman, We have read with great attention the article “Osteoporosis in the age COVID-19 patients”, written by Girgis and CliftonBligh (authors) in the July issue of Osteoporosis International. We welcome the opportunity to make a short comment as well. This very interesting article evaluates treatment of osteoporosis in disaster of COVID-19. The authors emphasized that osteoporosis kills and every year almost, 750,000 people lose their lives around the world as a result of hip fracture [1]. We want to highlight that older patients (very often with osteoporosis) are also with increased risk for mortality due to novelty SARS-CoV-2 pandemic. Evidence of osteoporosis associating nutritional factors; particularly calcium and vitamin D are reviewed as association of falls risk with fracture [2]. Unfortunately, in the group of very old patients with fragility fractures, only 28.6% were on adequate osteoporosis treatment [3]. High serum homocysteine has been shown to have detrimental effects on neural cells, vascular endothelial cells, osteoblasts, and osteoclasts. Therefore, hyperhomocysteinemiamay be regarded as a factor that can reduce both bone mass and impair bone quality [4]. In addition, high serum homocysteine often associated increased risk for fractures. Unfortunately, hyperhomocysteinemia appeared to be predictive of all-cause mortality, independent of frailty, an age-related clinical state characterized by a global impairment of physiological functions and involving multiple organ systems [5]. Values of vitamin B9 (folic acid) and B12 are in negative correlation with levels of homocysteine [6]. Furthermore, according to PubMed survey, there was no reliable data due to concomitance of COVID-19, hyperhomocysteinemia, and osteoporosis/fractures. So, what to do when we have older COVID-19 patient with hyperhomocysteinemia and high risk for bone fracture? Authors highlighted: “Clinicians need to adapt to the challenges posed by this crisis and consider ways to continue serving the most vulnerable amongst us, those with chronic disease with their own substantive morbidity and mortality”. In light of this, we suggest that level of homocysteine and B9/B12 vitamin should be measured at clinical follow-up in all older patients with COVID-19, immediately after hospitalization. If persistent, hyperhomocysteinemic proosteoporotic (but also prothrombotic) state should be promptly decreased in acute phase of COVID-19, on the base of Latin phrase primum non nocere. Our studies from Bosnia and Herzegovina showed that the intake of B9 vitamin, sometimes with B12 vitamin as well, was efficient in creating normalized homocysteine levels in older patients with ischemic stroke and Parkinson’s disease [7, 8]. Fortunately, risk of side effects is minimal if the daily dose of B9 vitamin is 1–5 mg [9]. So, we point out that B9/B12 vitamin are “on the first-line”—good and safe in reduction levels of homocysteine in various older patients. In addition, B2/B3/B6 vitamins are enhancers of the immune system and might be efficient as soldiers from second echelon in battling with COVID-19 [10]. All in all, B-vitamins can, ad hoc, become the medication of choice in the treatment when unhidden hyperhomocysteinemia/osteoporosis coexists with COVID-19. Lastly, we emphasize that further studies will elucidate proosteoporotic/prothrombotic potential of hyperhomocysteinemia in COVID-19 patients as well as beneficial add-on effects of B-vitamins. * S. Kunić suljo.kunic@hotmail.com