Background: Virtual reality (VR) and augmented reality (AR) have recently become popular research themes. However, there are no published bibliometric reports that have analyzed the corresponding scientific literature in relation to the application of these technologies in medicine. Objective: We used a bibliometric approach to identify and analyze the scientific literature on VR and AR research in medicine, revealing the popular research topics, key authors, scientific institutions, countries, and journals. We further aimed to capture and describe the themes and medical conditions most commonly investigated by VR and AR research. Methods: The Web of Science electronic database was searched to identify relevant papers on VR research in medicine. Basic publication and citation data were acquired using the “Analyze” and “Create Citation Report” functions of the database. Complete bibliographic data were exported to VOSviewer and Bibliometrix, dedicated bibliometric software packages, for further analyses. Visualization maps were generated to illustrate the recurring keywords and words mentioned in the titles and abstracts. Results: The analysis was based on data from 8399 papers. Major research themes were diagnostic and surgical procedures, as well as rehabilitation. Commonly studied medical conditions were pain, stroke, anxiety, depression, fear, cancer, and neurodegenerative disorders. Overall, contributions to the literature were globally distributed with heaviest contributions from the United States and United Kingdom. Studies from more clinically related research areas such as surgery, psychology, neurosciences, and rehabilitation had higher average numbers of citations than studies from computer sciences and engineering. Conclusions: The conducted bibliometric analysis unequivocally reveals the versatile emerging applications of VR and AR in medicine. With the further maturation of the technology and improved accessibility in countries where VR and AR research is strong, we expect it to have a marked impact on clinical practice and in the life of patients.

Akkermansia muciniphila and Faecalibacterium prausnitzii are highly abundant human gut microbes in healthy individuals, and reduced levels are associated with inflammation and alterations of metabolic processes involved in the development of type 2 diabetes. Dietary factors can influence the abundance of A. muciniphila and F. prausnitzii, but the evidence is not clear. We systematically searched PubMed and Embase to identify clinical trials investigating any dietary intervention in relation to A. muciniphila and F. prausnitzii. Overall, 29 unique trials were included, of which five examined A. muciniphila, 19 examined F. prausnitzii, and six examined both, in a total of 1444 participants. A caloric restriction diet and supplementation with pomegranate extract, resveratrol, polydextrose, yeast fermentate, sodium butyrate, and inulin increased the abundance of A. muciniphila, while a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols decreased the abundance of A. muciniphila. For F. prausnitzii, the main studied intervention was prebiotics (e.g. fructo-oligosaccharides, inulin type fructans, raffinose); seven studies reported an increase after prebiotic intervention, while two studies reported a decrease, and four studies reported no difference. Current evidence suggests that some dietary factors may influence the abundance of A. muciniphila and F. prausnitzii. However, more research is needed to support these microflora strains as targets of microbiome shifts with dietary intervention and their use as medical nutrition therapy in prevention and management of chronic disease.

The effect of postmenopausal hormone therapy (HT) on cardiovascular disease (CVD) risk remains controversial. We aimed to systematically review the evidence regarding the role of dose, route of hormone administration, timing of initiation and duration of HT on cardiovascular risk among postmenopausal women. The electronic databases Medline Ovid, Web of Science and Cochrane Central were systematically searched to identify studies published before 30 January 2018. Reference lists, using Elsevier's Scopus, of the included studies were searched for further identification of relevant studies. Clinical trials and observational studies that assessed clinical and subclinical cardiovascular outcomes in relation to dose, route of administration, duration of use, or timing of HT initiation among postmenopausal women were included. Data were extracted by independent reviewers using a pre-designed data collection form. The Cochrane Collaboration's tool and the Newcastle-Ottawa Scale were used by two independent investigators to assess the risk of bias in RCTs and in prospective observational studies, respectively. In total, 33 unique studies (6 trials and 27 prospective observational studies) were identified, including a total of 2 588 327 women. The synthesis of the existing knowledge on this topic was challenging due to inconsistent findings between some studies, caused by substantial diversity in scientific rigor and quality across the available literature. Overall, the evidence did not support the concerns that oral or transdermal HT increases heart disease risk. Contrary, observational data showed that a beneficial cardioprotective effect can be observed even with use of low doses of oral HT (effect of 0.3 mg/day of oral conjugated equine estrogen was similar to that seen with the standard dose of 0.625 mg/day), but clinical trials to support a cardioprotective benefit of HT in primary prevention have not been identified. Furthermore, the current data suggested that oral and transdermal HT, in dose-dependent manner and irrespective of HT formulation, may increase thromboembolic risk, as well as risk of stroke. However, transdermal estrogen with 10 years since the menopause onset (>60 years old), due to greater absolute risks of coronary heart disease, stroke and venous thromboembolism, HT should be used for the shortest time possible and in lowest possible dose and preferably transdermal administration should be recommended. However, an individualized treatment approach including baseline CVD risk assessment should be applied when prescribing HT. The majority of studies included in the current review are from North American and European populations, which might limit the generalizability of the findings of this review to the other populations. Finally, the quality of evidence included in this review was generally low or moderate, highlighting a need for more rigorous research to help us better understand HT and cardiovascular health.

Consumption of oat and buckwheat have been associated with various health benefits that may be attributed to their nutritional composition. We performed a systematic review to evaluate the profile and quantity of bioactive compounds present in oat and buckwheat. Among 154 studies included in final analysis, 113 and 178 bioactive compounds were reported in oat and buckwheat, respectively. Total phytosterols, tocols, flavonoids and rutin content were generally higher in buckwheat, β-glucans were significantly higher in oat, while avenanthramides and saponins were characteristically present in oat. The majority of studies included in current review were published before 2010s. The heterogeneous methodological procedures used across the studies precluded our possibility to meta-analyse the evidence and raises the need for harmonization of separation and extraction methods in future studies. Our findings should further stimulate the exploration of metabolites related to identified phytochemicals and their roles in human health.

Aims: The association between progestin-only contraceptive (POC) use and the risk of various cardiometabolic outcomes has rarely been studied. We performed a systematic review and meta-analysis to determine the impact of POC use on cardiometabolic outcomes including venous thromboembolism, myocardial infarction, stroke, hypertension and diabetes. Methods and results: Nineteen observational studies (seven cohort and 12 case–control) were included in this systematic review. Of those, nine studies reported the risk of venous thromboembolism, six reported the risk of myocardial infarction, six reported the risk of stroke, three reported the risk of hypertension and two studies reported the risk of developing diabetes with POC use. The pooled adjusted relative risks (RRs) for venous thromboembolism, myocardial infarction and stroke for oral POC users versus non-users based on the random effects model were 1.06 (95% confidence interval (CI) 0.70–1.62), 0.98 (95% CI 0.66–1.47) and 1.02 (95% CI 0.72–1.44), respectively. Stratified analysis by route of administration showed that injectable POC with a RR of 2.62 (95% CI 1.74–3.94), but not oral POCs (RR 1.06, 95% CI 0.7–1.62), was associated with an increased risk of venous thromboembolism. A decreased risk of venous thromboembolism in a subgroup of women using an intrauterine levonorgestrel device was observed with a RR of 0.53 (95% CI 0.32–0.89). No effect of POC use on blood pressure was found, but there was an indication for an increased risk of diabetes with injectable POCs, albeit non-significant. Conclusions: This systematic review and meta-analysis suggests that oral POC use is not associated with an increased risk of developing various cardiometabolic outcomes, whereas injectable POC use might increase the risk of venous thromboembolism.

Objective: Although positive psychology interventions (PPIs) are increasingly popular in chronic pain treatment their efficacy is still unclear. The objective is to summarize evidence on the effect of PPIs on pain, physical functioning, and emotional functioning in adults with chronic pain. Methods: Four electronic databases and additional references were searched for randomized controlled trials (RCTs) published between 1990 and 2020. Findings from included studies were qualitatively and quantitatively synthesized, and study quality was assessed for risk of bias. A random effects meta-analysis model was applied for outcomes with more than four findings. Results: Of 16 included RCTs, almost half delivered PPIs as self-help online interventions, and half conducted guided face-to-face interventions which lasted mostly eight weeks. Results from meta-analysis showed beneficial effects of PPIs compared to the control group on pain intensity and emotional functioning (i.e., less depressive symptoms, pain catastrophizing, negative affect; more positive affect) post-intervention. At 3-month follow-up, beneficial effects were maintained for depressive symptoms and positive and negative affect, but not for pain catastrophizing. However, the evidence on the long-term efficacy of PPIs and the efficacy of PPIs on physical functioning remains limited. Conclusions: This review supports the notion that PPIs are beneficial to chronic pain treatment, although further, high quality research is needed to support this conclusion.