Vegan/vegetarian diet and human milk donation: An EMBA survey across European milk banks.

The nutritional adequacy of human milk (HM) from vegan/vegetarian mothers has been a matter of debate, and a variety of recommendations regarding the eligibility of these mothers as human milk donors exists. According to the latest evidence, HM from vegans/vegetarians is similar in its composition to that from omnivores, however, some differences may be observed regarding vitamin B12 and omega-3 fatty acids concentrations. Maternal supplementation of these compounds has been proven effective in increasing their HM concentration. With this survey, we aimed to explore the practices currently in use in European human milk banks (HMBs) regarding potential donors following vegan/vegetarian diets. The online survey was distributed to European HMBs between January and July 2022. A total of 188 HMBs were contacted, and 118 replied (response rate 63%). Vegan and vegetarian mothers were recommended supplements of vitamin B12 to be accepted as donors in 27% and 26% of HMBs, respectively. Additional omega-3 fatty acid supplementation was required in 8% HMBs. In the remaining HMBs, these mothers were either systematically excluded or included regardless of supplementation. The dosage of the recommended supplements was extremely variable. Fifty-one percent of HMBs were following recommendations to guide their practice, national or local recommendations mainly. Great variability in European HMBs practices towards potential donors following vegan/vegetarian diets exists. Some of these practices can result in loss of donors and/or in potential nutritional deficiencies. Standardised evidence-based recommendations on this issue and their implementation in daily HMB practice are needed.

Maternal diet during breastfeeding in correlation to calcium and phosphorus concentrations in human milk.

BACKGROUND: The impact of maternal diet on mineral concentration in human milk (HM) remains unclear. The main aim of this study was to investigate the relationship between maternal dietary intake and calcium and phosphorus concentrations in HM. Furthermore, we aimed to evaluate the intake of both minerals by exclusively breastfed infants. METHODS: HM samples were obtained from 30 mothers at 6-8 weeks postpartum. Each mother was asked to express pre- and postfeeding milk four times during a 24-h period (6.00-12.00, 12.00-18.00, 18.00-24.00, 24.00-6.00). Maternal dietary assessment was based on a food frequency questionnaire and 3-day dietary records. Analysed minerals were determined using an inductively coupled plasma mass spectrometer (NexION 300D ICP mass spectrometer, Perkin Elmer SCIEX). RESULTS: The mean concentrations of calcium and phosphorus in HM samples were 278.7 ± 61.0 and 137.1 ± 21.9 mg/L, respectively, maintaining 2:1 ratio by weight. The concentration of both minerals was correlated with each other (r = 0.632, p = <0.001). The infants' mean calcium intake was 149.53 ± 36.41 mg/L, and their mean phosphorus intake was 74.62 ± 19.41 mg/L. The risk of insufficient intake of calcium was reported in 60% of infants (n = 18). Spearman's/Pearson's correlation coefficients did not reveal any correlations between HM calcium concentration and maternal diet, contrary to HM phosphorus concentration, which was positively correlated with energy (r = 0.369, p = 0.045), total protein (r = 0.464, p = 0.01), calcium (r = 385, p = 0.036), phosphorus (r = 501, p = 0.005), niacin (p < 0.001) and pyridoxine (r = 382, 0.037) intake. However, in multivariable analysis we observed that maternal dietary intake of both minerals had a positive influence on their concentration in HM. CONCLUSIONS: Maternal calcium and phosphorus intake influenced the concentration of both minerals in HM; however, the relationship was rather weak. In addition, we observed that calcium intake by most of the exclusively breastfed infants was insufficient to meet the recommended daily intake.

Cladribine tablets for highly active relapsing-remitting multiple sclerosis in Poland: a real-world, multi-centre, retrospective, cohort study during the COVID-19 pandemic.

INTRODUCTION: Treatment with cladribine tablets is indicated in highly active relapsing-remitting multiple sclerosis (RRMS). Cladribine tablets proved safe and effective in the pivotal CLARITY trial, but that trial included primarily treatment-naïve patients. In clinical practice however, cladribine tablets are often given to patients who have failed other treatments. Therefore, this study investigated the real-world safety and efficacy of cladribine tablets. MATERIAL AND METHODS: We gathered data from nine MS clinical centres across Poland for patients with RRMS who started treatment with cladribine tablets from December 2019 to June 2022. RESULTS: We enrolled 140 patients, with follow-up data available for 136 in year 1 and for 66 in year 2. At baseline, the mean age was 35.6 years, mean disease duration was 7.3 years, median EDSS score was 2.5, and 94% of patients were treatment- -experienced. Thirty-nine patients (27.9%) had undergone COVID-19, and 94 (67.1%) were vaccinated against COVID-19. The annualised relapse rate (ARR) decreased from 1.49 at baseline to 0.33 in year 1 (p < 0.001) and to 0.25 in year 2 (p < 0.001). The percentage of relapse-free patients increased from 11.5% at baseline to 70.2% in year 1 and 82.1% in year 2. The percentage of patients with active lesions decreased from 91.4% at baseline to 36.2% in year 1 and 18.2% in year 2. EDSS score remained stable or improved in 83.7% of patients in year 1 and 89.6% in year 2. No evidence of disease activity (NEDA-3) was achieved in 42.7% of patients in year 1 and 66.7% in year 2. Only one patient (0.72%) had grade 4 lymphopenia and 21 (15.1%) had grade 3 lymphopenia. Varicella zoster virus infections occurred in three patients. Eight patients discontinued treatment with cladribine: five due to inefficacy, one due to lymphopenia, and two due to a personal decision. CONCLUSIONS: Cladribine tablets proved safe and effective in a real-world cohort of treatment-experienced patients. However, the efficacy measures improved to a lesser extent in our cohort than in the pivotal clinical trial, which is probably due to a higher proportion of treatment-experienced patients in our cohort.

Nutrients and Bioactive Components of Human Milk After One Year of Lactation: Implication for Human Milk Banks.

OBJECTIVE: Specifying the nutrient content and bioactive compounds in milk from long-term lactation for the purpose of finding additional sources of donors' milk for human milk banks. METHOD: Human milk samples were collected from 43 mothers of term infants (term infant human milk, TIHM) (3-6 weeks of lactation) and 50 mothers who have breastfed for over a year (long-nursing human milk, LNHM). The milk collection time was 24 hours. The analyses of fat, protein, carbohydrate and energy content were performed with human milk analyzer MIRIS (Miris HMA™ ); lactoferrin and vitamin C content using high performance liquid chromatography in reversed phase (RP-HPLC); total antioxidant activity (TAC) and lysozyme by enzyme-linked immunosorbent assay (ELISA); and the activity of glutathione peroxidase (GPx) and catalase (CAT) via spectrophotometric methods. Sociodemographic characteristics of both groups of mothers have been compiled. RESULTS: Higher fat content and energy value was found in LNHM than in TIHM. Protein content in LNHM and TIHM did not differ. Carbohydrate content was lower in LNHM than in TIHM. TAC, CAT and GPx activity were higher in LNHM compared to TIHM. No significant differences in the content of lysozyme, lactoferrin and vitamin C between the studied groups were found. CONCLUSIONS: The findings suggest that after 12 months of lactation, human milk still has significant nutritional value, does not lose bioactive components and can be considered for use in human milk banks.

The legislative framework of donor human milk and human milk banking in Europe.

Data about the regulatory approaches to donor human milk (DHM) in European countries are lacking. The aim of this study is to describe the various regulations of DHM within European countries, to assess its legislative context and its impact in relation to donor milk banking. We performed a cross-sectional survey using a semistructured online questionnaire addressing 29 national European milk-banking representatives from June 2020 to February 2021. Representatives of 26 national DHM services participated in this study. The legal classification and regulatory status of DHM were defined in 9 out of 26 areas of jurisdiction (35%) as either food product (n = 6), product of human origin according to a blood, tissue, cell regulation (n = 2), or medicinal product (n = 1). In the remainder, DHM remains unclassified. Most legislations did not provide a comprehensive framework concerning DHM and costs to cover milk bank operations were rarely reimbursed. In general, the lack of national legislative governance and the actual legislative regulations in place do not support the use of DHM in European countries. National medical guidelines for the use of DHM have been issued in only 11 countries. The current number and distribution of milk banks (n = 239) within participating countries may not provide an equitable access to DHM for eligible infants. These findings could guide stakeholders aiming to establish a regulatory framework for DHM.

Neurotrophic Factors in Human Milk in Early Lactation and the Effect of Holder and Microwave Pasteurization on Their Concentrations.

OBJECTIVES: The objective of this study was to determine the level of brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) in human milk in the first 2 weeks of breast-feeding and compare the effects of Holder pasteurization (HoP, 62.5 °C, 30 minutes) and microwave pasteurization (MP) at constant temperature (62.5 °C) on the concentraion of both neurotrophic factors (NFs). METHODS: Concentration of NFs in human milk was determined using a commercially available ELISA assay. RESULTS: The average concentration of BDNF and GDNF in milk was 11 ±â€Š6 ng/mL and 336 ±â€Š238 pg/mL, respectively. There was a positive correlation between the concentrations of BDNF and GDNF in human milk and day of lactation (r = 0.441, P < 0.05 and r = 0.482, P < 0.05, respectively). In addition, there was a significant correlation between the levels of BDNF and GDNF (r = 0.366, P < 0.05). HoP and MP for 10 minutes affected both NF levels similarly, causing degradation of BDNF by about 24% and 17%, and GDNF by 47% and 45%, respectively. Use of MP for 5 minutes resulted in preservation of nearly 91% BDNF and 79% GDNF in human milk. CONCLUSIONS: In the pasteurization processes carried out, results showed that GDNF is more susceptible to degradation under the influence of high temperature. To the authors' best knowledge, this is the first study evaluating the effects of HoP and MP at constant temperature on the concentration of NFs in human milk. It was found that the MP for 5 minutes is the optimal method.

Maintaining human milk bank services throughout the COVID-19 pandemic: A global response.

If maternal milk is unavailable, the World Health Organization recommends that the first alternative should be pasteurised donor human milk (DHM). Human milk banks (HMBs) screen and recruit milk donors, and DHM principally feeds very low birth weight babies, reducing the risk of complications and supporting maternal breastfeeding where used alongside optimal lactation support. The COVID-19 pandemic has presented a range of challenges to HMBs worldwide. This study aimed to understand the impacts of the pandemic on HMB services and develop initial guidance regarding risk limitation. A Virtual Collaborative Network (VCN) comprising over 80 HMB leaders from 36 countries was formed in March 2020 and included academics and nongovernmental organisations. Individual milk banks, national networks and regional associations submitted data regarding the number of HMBs, volume of DHM produced and number of recipients in each global region. Estimates were calculated in the context of missing or incomplete data. Through open-ended questioning, the experiences of milk banks from each country in the first 2 months of the pandemic were collected and major themes identified. According to data collected from 446 individual HMBs, more than 800,000 infants receive DHM worldwide each year. Seven pandemic-related specific vulnerabilities to service provision were identified, including sufficient donors, prescreening disruption, DHM availability, logistics, communication, safe handling and contingency planning, which were highly context-dependent. The VCN now plans a formal consensus approach to the optimal response of HMBs to new pathogens using crowdsourced data, enabling the benchmarking of future strategies to support DHM access and neonatal health in future emergencies.

Effect of Nonthermal Processing on Human Milk Bactericidal Activity Against Escherichia coli.

Nonthermal methods are more efficient at preserving various biological properties of human milk, as compared with holder pasteurization (HoP), which is the most common preservation method. This study was performed to assess the effects of nonthermal processing on bactericidal activity against Escherichia coli in human milk. Milk samples obtained from the Regional Human Milk Bank in Warsaw at Holy Family Hospital were processed by HoP, irradiated with ultraviolet-C (UV-C) for 5, 10, and 15 minutes (6720 J/L each minute), subjected to 2 variations of high-pressure processing (HPP): 450 MPa for 15 minutes and 200 MPa for 10 minutes + 400 MPa for 10 min, with a 10-minutes break. The samples were then evaluated by a bactericidal assay (raw untreated human milk was used as a control). The bactericidal capacity after HoP was preserved in 12.1% of samples, showing a significant reduction in bactericidal properties compared with in raw milk (P < 0.05). The differences between samples preserved by nonthermal methods and raw milk were not significant (P > 0.05). Nonthermal methods of human milk treatment better preserve the bactericidal capacity compared with holder pasteurisation. Those alternative technologies to HoP can be proposed after further investigation for milk processing for Human Milk Banks facilities.

Correlation between human milk composition and maternal nutritional status

Background: Human milk is the optimal nutrition for newborns and infants during the first period of their life ­ from birth to 6-th month. It contains a uniquely quantitative and qualitative balanced nutrients profile. Composition of breast milk is dynamic and may vary according to maternal nutritional status. Objective: The aim of this study was to investigate associations between human milk composition and maternal nutritional status. Material and methods: One-day milk samples were provided by exclusively breastfeeding mothers (n=40) at the first month of lactation. Protein ­ total and true, fat, carbohydrate, dry matter and energy content were determined using the Human Milk Analyzer by MIRIS. The anthropometric measurements (current body weight, height) were used to calculate current body mass index (BMI). On this basis, we assessed nutritional status of examined population. Results: For the majority of women (75%, n=30) currently BMI value was in range of 18.5-24.9 kg/m2, for the rest of women it was ≥ 25 kg/m2. The median macronutrient composition per 100 ml of mature breast milk was 7.0 g for carbohydrate, 1.1 g for protein, 3.5 g for fat, 11.9 for dry matter and energy content was 66.0 kcal. Maternal body mass index was positively related to lipid, dry matter and energy breast milk content (p<0.05). Conclusions: The majority of examined women in the first month of lactation was in normal state of nutrition. For the rest of women BMI values indicated for overweight. Our results confirm correlation between human milk composition and maternal nutritional status, especially in matters of energy value and fat content in human milk.

Nutrition during breastfeeding - impact on human milk composition.

Breastfeeding or breast milk feeding is a gold standard of feeding of newborns and infants. According to the guidelines of the World Health Organisation exclusive feeding with breast milk should be applied until the end of 6 months of age and should be continued during subsequent months with simultaneous introduction of supplementary food. Composition of breast milk varies and the composition of individual nutrients is affected by, among others, the diet of a breastfeeding mother. The paper aimed to present a literature review in order to assess a correlation between the mother's diet and breast milk composition. It has been observed that nutrients with the greatest correlation between their levels in human milk and their levels in the mother's diet include polyunsaturated fatty acids, especially DHA; however, no correlation was observed for mineral elements, mainly trace elements (zinc, chromium and iron).

Characteristics of the regional human milk bank in Poland - donors, recipients and nutritional value of human milk

Background: In case of shortage of breast milk despite proper lactation care or the poor state of the mother's health, breast milk from human milk bank is recommended for feeding preterm infants Objective: This study retrospectively evaluated the first year of the operation of the Regional Human Milk Bank Material and methods: Data concerning donors was collected in the human milk bank during the cooperation. The clinical characteristics of the recipients was made on the basis of medical documentation from the Holy Family Hospital in Warsaw, Poland. Analysis of nutritional value was performed with the human milk analyzer (MIRIS AB) Results: In the first year of activity, 45 voluntary donors established cooperation, donating from 650 to 32030 ml of human milk. The content of nutrients in milk provided by donors was variable - protein 0.4-1.5 g / 100 ml, fat 1.1-7.4 g / 100 ml, carbohydrates 6.3-7.9 g / 100 ml. The average length of using donated human milk was 4 days and the average volume of milk for one infant was 282 ml Conclusions: The donor profiles have a significant impact on the milk composition form HMB. The nutritional value can be improved by recruitment donors from mothers that gave birth prematurely and by beginning donation at earlier stages of lactation as soon as lactation is stabilized. In case of shortage of mothers own milk the immediate implementation of donors milk as a short-term support can significantly reduce the food intolerance incidence in the group of prematurely born infants

Essential and non-essential element concentrations in human milk samples and the assessment of infants' exposure.

As the data concerning element concentrations in human milk (HM) samples and their intake by infants are lacking in Poland, the present study aimed to explore this issue. The material consisted of HM samples obtained from 30 exclusively breastfeeding mothers during 4-6 weeks postpartum. Additionally, to identify the factors that may potentially affect HM composition, information regarding maternal data (anthropometry, body composition, and diet) was also collected. Maternal diet was assessed with two methods-a food frequency questionnaire and 3-day dietary records. In total, 18 essential and non-essential elements were determined. For the elements analysis, we used inductively coupled plasma quadrupole mass spectrometry. Most of the elements (n = 11, 61%) were detected in all HM samples. In all HM samples tin concentration was higher (5.67 ± 2.39 µg/L) than the usual range reported by the World Health Organization (~ 1.0 µg/L). HM cadmium content was positively associated with maternal salty snacks intake (r = 0.502, p = 0.005), arsenic with whole-grain products intake (r = 0.37, p = 0.043), and mercury concentration with fruits and seeds/nuts consumption (r = 0.424, p = 0.042 and r = 0.378, p = 0.039, respectively). Higher HM lead concentration was predicted by maternal age (95% CI [0.94-0.97]), intake of fish (95% CI [1.01-1.03]), and vegetables (95% CI [1.02-1.06]). The highest infants' intake was observed for copper (35.24 ± 12.48) and the lowest for arsenic (0.076 ± 0.102). Infants' exposure to lead was associated with maternal frequency consumption of canned fish (p = 0.0045). There is a need to perform further research on this topic to maximize the benefits of breastfeeding by minimizing maternal and infant exposure to potentially toxic elements.

Breastmilk mineral composition among well-educated mothers from Central Poland - Associations with maternal dietary intake, dietary patterns and infant psychomotor development.

BACKGROUND: Maternal dietary habits could affect breastmilk mineral composition, which may influence infant development. Mineral dietary intake or supplementation slightly affects its breastmilk concentration. However, the intake of selected food groups or dietary patterns that reflect diet complexity could have a greater impact. Hence, the aim of the study was to assess breastmilk mineral composition at one, three, and six months of lactation among mothers living in urban area of Central Poland, as well as the evaluate maternal dietary determinants and associations with infant anthropometric and psychomotor development. METHODS: The study was conducted among 43 healthy and exclusively breastfeeding mothers. In the first, third, and sixth months of lactation, we collected breastmilk samples and assessed the concentration of Ca, P, Zn, Fe, Se, Ni, As, Pb, and Cd using the ICP-MS method. Maternal dietary habits were evaluated by a food frequency questionnaire in the first month of lactation, whereas in the third and sixth by the three-day food record. Based on the collected data adherence to the Polish-adapted Mediterranean (Pl-aMED; 1 month) and the DASH diet (Mellen's Index; 3 and 6 months) was assessed. In the third and sixth months of lactation infant anthropometric parameters and the sixth month of lactation psychomotor development were evaluated. RESULTS: Breastmilk Se, Ni, As, Pb, and Cd levels were under the LOQ in all the breastmilk samples at all study visits. Median breastmilk mineral concentrations of Ca, P, Zn, and Fe in the first, third, and sixth months of lactation varied from 381.9 to 332.7 mg/L, 161.6 to 139.1 mg/L, 2.2 to 0.8 mg/L, and 0.26 to 0.17 mg/L, respectively. Maternal dietary intake and supplementation did not affect breastmilk Ca, P, Zn, and Fe. Pl-aMED scores were associated with breastmilk Ca (ß = 0.489, 95% CI 0.180 - 0.799, p = 0.003) and Zn (ß = 0.499, 95% CI 0.199 - 0.798, p = 0.002) in the first month of lactation, whereas no association with the DASH diet were observed in the third and sixth month of lactation. Breastmilk Fe in the third month was associated with infant motor development (ß = 0.420, 95% CI 0.113 - 0.727, p = 0.009) in the sixth month of life, but no other associations with anthropometric or psychomotor development were observed. Moreover, we estimated that few infants meet their adequate intake (AI) requirements for P, Zn, and Fe. CONCLUSION: Our study showed that maternal adherence to Pl-aMED is a significant predictor of breastmilk Ca and Zn in the first month of lactation, which may be especially important considering that more than 75% of infants had inadequate Zn intake. Moreover, we found that breastmilk Fe positively influenced infant motor development, despite the majority of infants having inadequate intake. On the other hand, no infant had deficiency symptoms, which emphasizes the necessity to evaluate of AI norms for infants.

"I could not find the strength to resist the pressure of the medical staff, to refuse to give commercial milk formula": a qualitative study on effects of the war on Ukrainian women's infant feeding.

Introduction: During emergencies, breastfeeding protects infants by providing essential nutrients, food security, comfort, and protection and is a priority lifesaving intervention. On February 24, 2022, the war in Ukraine escalated, creating a humanitarian catastrophe. The war has resulted in death, injuries, and mass internal displacement of over 5 million people. A further 8.2 million people have taken refuge in neighboring countries, including Poland. Among those impacted are infants and young children and their mothers. We conducted a study to explore the infant feeding challenges and needs of Ukrainian women affected by the war. Methods: We conducted a qualitative descriptive study involving in-depth interviews (IDIs) with 75 war-affected Ukrainian mothers who had at least one infant aged less than 12 months at the time of the interview. Eligible mothers were either (1) living as Ukrainian refugees in Poland, having crossed the border from Ukraine on or after February 24, 2022, when the war started (n = 30) or (2) living in Ukraine as internally displaced persons or as residents in the community (n = 45). All interviews were audio-recorded (either transcribed or had responses summarized as expanded notes) and analyzed using qualitative thematic analysis using a two-step rapid analysis process. Results: Participants in Ukraine who wanted to initiate breastfeeding right after birth faced opposition from healthcare workers at maternity hospitals. Ukrainian refugees who gave birth in Poland faced language barriers when seeking breastfeeding support. Half of the participants in Ukraine received commercial milk formula (CMF) donations even if they said they did not need them. Most respondents stated that breastfeeding information and support were urgently needed. Conclusion: Our data suggests that healthcare workers in Ukrainian maternity hospitals require additional training and motivation on delivering breastfeeding support. In addition, lactation consultants in maternity ward are needed in Ukraine, and interpretation support is needed for refugees to overcome language barriers. There is a need to control the indiscriminate donations of commercial milk formula and to ensure that complementary foods and commercial milk formula are available to those that need it. This study confirms the need for actions to ensure infant and young child feeding (IYCF) support is provided during emergencies.

Feeding Strategies in Newborns and Infants During the COVID-19 Pandemic-Polish Cross-Sectional Study.

Objective: We aimed to analyze factors affecting feeding strategies of newborns and infants during the COVID-19 pandemic in Poland. Methods: The cross-sectional study using a self-developed CAWI questionnaire was conducted between February and April 2021 among Polish mothers. The analysis included responses from 1,485 women who delivered during the COVID-19 pandemic restrictions. The inferential analysis uses Parson's chi-square test and the series of logistic models. The data were weighted to adjust age and educational level distribution. Results: When hospitalized, lack of skin-to-skin contact (OR = 0.094; p < 0.001, 95% CI [0.057 0.156]), not being informed about direct breastfeeding in the pandemic (OR = 0.195, p = 0.006, 95% CI [0.61 0.62]) and being suspected for COVID-19 (OR = 0.379, p < 0.001, 95% CI [0.223 0.642]) reduced the probability of breastfeeding. Feeding plans and feeding after leaving the hospital were impacted only by the educational level (OR = 2.463, p = 0.028, 95% CI [1.1 5.518]). Conclusion: While the mother's education level plays a key role in the nutrition plans and long-term feeding strategy, PUI status and hospital practices (lack of skin-to-skin and proper information) had a major negative impact on breastfeeding rates in the hospital.

The cytokine trio - visfatin, placental growth factor and fractalkine - and their role in myocardial infarction with non-obstructive coronary arteries (MINOCA).

Myocardial infarction with nonobstructive coronary arteries (MINOCA) remains a puzzling clinical entity. It is characterized by clinical evidence of myocardial infarction (MI) with normal or near-normal coronary arteries in angiography. Given the complex etiology including multiple possible scenarios with varied pathogenetic mechanisms, profound investigation of the plausible biomarkers of MINOCA may bring further pathophysiological insights and novel diagnostic opportunities. Cytokines have a great diagnostic potential and are used as biomarkers for many diseases. An unusual trio of visfatin, placental growth factor (PlGF) and fractalkine (CX3CL1) can directly promote vascular dysfunction, inflammation and angiogenesis through the activation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling. They are redundant in physiological processes and become overexpressed in the pathomechanisms underlying MINOCA. The knowledge about their concentration might serve as a valuable diagnostic and/or therapeutic tool for assessing vascular endothelial function. Here we analyze the current knowledge on visfatin, PlGF and CX3CL1 in the context of MINOCA and present the novel clinical implications of their combined expression as predictors or indicators of this condition.

Heart rate variability as a predictor of stroke course, functional outcome, and medical complications: A systematic review.

Background: Heart rate variability (HRV) is a non-invasive marker of autonomic nervous system function that is based on the analysis of length differences between subsequent RR intervals of the electrocardiogram. The aim of this systematic review was to assess the current knowledge gap in the utility of HRV parameters and their value as predictors of the acute stroke course. Methods: A systematic review was performed in accordance with the PRISMA guidelines. Relevant articles published between 1 January 2016 and 1 November 2022 available in the PubMed, Web of Science, Scopus, and Cochrane Library databases were obtained using a systematic search strategy. The following keywords were used to screen the publications: "heart rate variability" AND/OR "HRV" AND "stroke." The eligibility criteria that clearly identified and described outcomes and outlined restrictions on HRV measurement were pre-established by the authors. Articles assessing the relationship between HRV measured in the acute phase of stroke and at least one stroke outcome were considered. The observation period did not exceed 12 months. Studies that included patients with medical conditions influencing HRV with no established stroke etiology and non-human subjects were excluded from the analysis. To minimize the risk of bias, disagreements throughout the search and analysis were resolved by two independent supervisors. Results: Of the 1,305 records obtained from the systematic search based on keywords, 36 were included in the final review. These publications provided insight into the usability of linear and non-linear HRV analysis in predicting the course, complications, and mortality of stroke. Furthermore, some modern techniques, such as HRV biofeedback, for the improvement of cognition performance after a stroke are discussed. Discussion: The present study showed that HRV could be considered a promising biomarker of a stroke outcome and its complications. However, further research is needed to establish a methodology for appropriate quantification and interpretation of HRV-derived parameters.

Can HRV Predict Prolonged Hospitalization and Favorable or Unfavorable Short-Term Outcome in Patients with Acute Ischemic Stroke?

The aim of this study was to assess whether the heart rate variability (HRV) could predict a favorable or unfavorable stroke outcome. The endpoint was based on the National Institutes of Health Stroke Scale (NIHSS). The patient's health condition was assessed upon discharge from the hospital. An unfavorable stroke outcome was defined as death or NIHSS ≥ 9, while NIHSS < 9 meant a favorable stroke outcome. The studied group consisted of 59 patients with acute ischemic stroke AIS (mean age of 65.6 ± 13.2; 58% were females). An original and innovative non-linear measure was used to analyze HRV. It was based on symbolic dynamics consisting of comparing the "length of the longest words" in the night recording of HRV. "The length of the longest word" meant the longest sequence of identical adjacent symbols possible for a patient. An unfavorable stroke outcome occurred in 22 patients, whereas the majority of patients (37) had a favorable stroke outcome. The average hospitalization time of patients with clinical progression was 29 ± 14 days, and with favorable outcomes was 10 ± 3 days. Patients with long words (more than 150 adjacent RR intervals having the same symbol) were hospitalized no longer than 14 days and they had no clinical progression. The patients with a favorable stroke outcome were characterized by longer words. Our pilot study may be the beginning of work on the development of a non-linear, symbolic method as a predictor of prolonged hospitalization and increased risk of clinical progression in patients with AIS.