OBJECTIVE: This systematic review aimed to review epidemiological reports to determine the prevalence of MCI and its associated risk factors in LMICs.
METHODS: Medline, Embase, and PsycINFO were searched from inception until November 2019. Eligible articles reported on MCI in population or community-based studies from LMICs and were included as long as MCI was clearly defined.
RESULTS: 5,568 articles were screened, and 78 retained. In total, n = 23 different LMICs were represented; mostly from China (n = 55 studies). Few studies were from countries defined as lower-middle income (n = 14), low income (n = 4), or from population representative samples (n = 4). There was large heterogeneity in how MCI was diagnosed; with Petersen criteria the most commonly applied (n = 26). Prevalence of amnesic MCI (aMCI) (Petersen criteria) ranged from 0.6%to 22.3%. Similar variability existed across studies using the International Working Group Criteria for aMCI (range 4.5%to 18.3%) and all-MCI (range 6.1%to 30.4%). Risk of MCI was associated with demographic (e.g., age), health (e.g., cardio-metabolic disease), and lifestyle (e.g., social isolation, smoking, diet and physical activity) factors.
CONCLUSION: Outside of China, few MCI studies have been conducted in LMIC settings. There is an urgent need for population representative epidemiological studies to determine MCI prevalence in LMICs. MCI diagnostic methodology also needs to be standardized. This will allow for cross-study comparison and future resource planning.
EVIDENCE ACQUISITION: This study was based on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyzes) statement guidelines for a systematic review of the academic databases Scopus, Web of Science, PubMed, EBSCOhost (SportDiscus), and Google Scholar. The PEDro scale was used to assess the methodological quality of the included publications, which ranged from moderate to high quality. The systematic review protocol was registered on inplasy.com (INPLASY202380049).
EVIDENCE SYNTHESIS: Out of 249 studies identified, 93 articles were evaluated as eligible, and after the screening, 18 studies were finally included in this systematic review. Meta-analysis results showed a significant enhancement on vertical jump height in the BFRT group compared to the control group (SMD=1.39, 95% CI=0.30-2.49, P=0.01). BFRT was able to significantly increase maximal oxygen uptake (SMD=1.65, 95% CI=0.56-2.74, P<0.01). While no significant improvement in sprint time was observed (SMD= -0.18, 95% CI=-1.18-0.82, P=0.115).
CONCLUSIONS: The finding suggests that BFRT is beneficial to athletes as this training method can be effective in enhancing physical and technical performance in athletes. Nevertheless, further analysis needs to be conducted to fully determine the effectiveness of the moderators of the intervention on sports performance.