BackgroundWhen lowlanders rapidly ascend to altitudes > 2500 m, they may develop acute mountain sickness (AMS). The individual susceptibility, ascending velocity, time spent at altitude, activity levels and altitude reached are considered risk factors for AMS. However, it is not clear whether sex is a risk factor. The results have been inconclusive. We conducted a meta-analysis to test whether there were sex-based differences in the prevalence of AMS using Lake Louise Scoring System.MethodsSystematic searches were performed in August 2019 in EMBASE, PubMed, and Web of Science for prospective studies with AMS data for men and women. The titles and abstracts were independently checked in the primary screening step, and the selected full-text articles were independently assessed in the secondary screening step by the two authors (YPH and JLW) based on pre-defined inclusion criteria. The meta-analysis was performed using by the STATA 14.1 software program. A random-effects model was employed.ResultsEighteen eligible prospective studies were included. A total of 7669 participants (2639 [34.4%] women) were tested. The results showed that there was a statistically significant higher prevalence rate of AMS in women than in men (RR = 1.24, 95%CI 1.09–1.41), regardless of age or race. Howerver, the heterogeneity was significant in the analysis (Tau2 = 0.0403, Chi2 = 50.15, df = 17; I2 = 66.1%, P = 0.000), it was main caused by different numbers of subjects among the studies (coefficient = − 2.17, P = 0.049). Besides, the results showed that there was no evidence of significant publication bias in the combined studies on the basis of Egger’s test (bias coefficient = 1.48, P = 0.052) and Begg’s test (P = 0.130).ConclusionsAccording to this study, the statistically significant finding emerging from this study was that women have a higher prevalence of AMS. However, the authors could not exclude studies where patients were on acetazolamide. Our analysis provided a direction for future studies of the relationship of sex and the risk of AMS, such as the pathological mechanism and prevention research.

The potential association between medical resources and the proportion of oldest-old (90 years of age and above) in the Chinese population was examined, and we found that the higher proportion of oldest-old was associated with the higher number of beds in hospitals and health centers.

Summary Laparoscopic adjustable gastric banding (LAGB) is gaining popularity as a technique for achieving effective weight loss in the severely obese population. It is a minimally invasive procedure and the reported early morbidity is low. However, we have observed at our institution that occasional patients complain of central chest pain, mimicking angina (verbal pain score of > 7 out of 10), within 2 h after the procedure. This is a worrying symptom because obesity is known to be a major risk factor for developing cardiovascular complications. We have now performed 250 LAGB operations at our hospital. The following four case reports document our patients who presented with early chest pain postoperatively. Common characteristics of male gender, morbid obesity and some degree of obstructive sleep apnoea were identified among the cases. The aetiology of the chest pain is uncertain; nevertheless, close monitoring is vital to exclude pathological events such as acute coronary syndrome.