RESUMO
Sleep is integral to human health. Accumulating evidence has revealed that sleep characteristics could be influenced by altitudes. However, few studies explored what the trajectories of sleep status are along with the altitudes. Therefore, this study aims to find the relationship between altitudes and sleep status using data from CHARLS, a nationwide survey data from China. The generalized additive model and generalized additive mixed-effects model were used to explore the association between sleep status and altitudes. Age, gender, education level, and other common confounding factors were included in the models as covariates. The sleep duration showed a rapid increase trend after the altitude of 1600 m. The probabilities of long sleep duration were increased with the evaluation of altitudes (edf = 1.945, P = 0.004), while the similar statistically significant change was not observed for short sleep duration (edf = 2.204, P = 0.193). Gender, residence, and ethnicity were the main influencing factors for the increase in sleep duration as altitude increased. The high-altitude environment could have effects on the sleep status of individuals, especially on the sleep duration. Long sleep duration was found more prevalent among highlanders. This study shed light on the underlying relationship between altitudes and sleep status which could provide clues for further mechanism studies. Supplementary Information: The online version contains supplementary material available at 10.1007/s41105-024-00527-y.
RESUMO
OBJECTIVE: It is crucial to conduct systematic reviews (SRs) and meta-analyses (MAs) to make causal references, in order to inform the clinical guidelines and decision-making. The high reporting quality of reviews through compliance with the guidelines Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Assessing the Methodological Quality of Systematic Reviews-2 (AMSTAR-2) could promote the consistency and reproducibility across the published articles. The purpose of this meta-epidemiological study is to evaluate the reporting methodological quality of SRs on the association between sleep duration and hypertension. METHODS: An electronic search in an online database was performed to retrieve systematic reviews and meta-analyses published up to 31st December 2022. Data screening and extraction were conducted by two investigators. The reporting quality of each included article was measured with reference to the 27-item 2020 PRISMA checklist, and methodological quality was evaluated using the AMSTAR-2. PRISMA evaluation was determined by total scores of individual SR and items scores and AMSTAR-2 assessment was also conducted using four categories. RESULTS: Of 2269 articles captured in the initial search, 15 SRs were included in the final analyses. All SRs had more than one incomplete PRISMA item. The mean of total scores was 20.5 (range 14-25), and the results of the AMSTAR-2 assessment were critically low to low. The reporting quality of "rationale," "objectives," "selection process," "study selection," "discussion," and 'support' was fully reported. SRs that reported registration information and protocol had a higher PRISMA score than articles that reported certain deficiencies. From the results of the AMSTAR-2 assessment, the methodological quality of these SRs and MAs was critically low to low. None of the included literature provided a list of excluded articles, and the report of the search strategy was incomplete; half of the SRs did not use appropriate tools to assess the risk of bias in each included study. CONCLUSIONS: Both the reporting and methodological quality of overall studies are less than ideal, with several key items being consistently under-reported. The quality measured by AMSTAR-2 is mainly consistent with the quality of reporting. Authors, reviewers, and journal editors should raise awareness and move forward to encourage completeness of SR reporting based on the results, which can aid in enhancing the quality of evidence. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42023459901.