Incidence of Mild Cognitive Impairment with Ascending Altitude

Abstract

Background: This study aimed to longitudinally quantify the prevalence of mild cognitive impairment (MCI) in individual trekkers at three different ascending altitudes (Site 1: *3500 m, Site 2: *4400 m, and Site 3: *5100 m). We correlated these findings with the presence of acute mountain sickness (AMS). Materials and Methods: We performed serial assays using the environmental quick mild cognitive impairment (eQMCI) score on 103 English-speaking 18-to 65-year-old volunteers trekking to Everest Base Camp in Nepal during spring 2016. We defined MCI as a score less than 67 (lower scores indicating more cognitive impairment). Additional data collected included the Lake Louise Score, demographics, and other possible confounders. Results: eQMCI scores significantly decreased with ascent from Site 1 to 2 (a score of 78.95 [SD = 7.96] to 74.67 [SD = 8.8] [Site 1-2 p = 0.04]), but then increased on ascent to Site 3 to 83.68 (SD = 8.67) (Site 1-3 p = <0.0001, Site 2-3 p = <0.0001). However, subjects who fulfilled eQMCI criteria for MCI increased despite the overall improvement in score: 6.8% (N = 7) at Site 1, 18.7% (N = 14) at Site 2, and 3.3% (N = 2) at Site 3. Incidence of AMS at Sites 1, 2, and 3 was 22.3% (N = 23), 21.3% (N = 16), and 48.3% (N = 29), respectively. Of those with MCI, 1.94% met criteria for AMS at Site 1 ( p = 0.0017), 2.67% at Site 2 ( p = 0.6949), and 3.33% at Site 3 ( p = <0.0001). Conclusions: There is a significant incidence of MCI at high altitude, even in those without subjective findings of AMS. Interestingly, subjects with a decline in cognitive function show an increasing trend for developing AMS at higher altitude. Future research on the clinical impact of MCI on a subject's health, judgment, and performance remains to be elucidated.

Clinical prediction of magnetic resonance image compilation in patients with mild cognitive impairment

“…At present, numerous treatment methods such as drug treatment, psychotherapy, and surgery are utilized to treat the patients with MCI, and these treatment methods have certain protective effect in preventing or slowing the development progress of MCI. However, the study by Overton M reports that nearly 30% of patients with MCI will develop to Alzheimer's disease, and Alzheimer's disease will cause greater damage to health, cognitive function, memory function, and lives in patients (Algaze et al, 2020; Overton et al, 2019). How to choose an appropriate method to prevent MCI development is an urgent problem to solve.…”

The role of post-translational modifications in driving abnormal cardiovascular complications at high altitude

“…Specifically, it was reported that high altitude could induce irreversible/reversible damage to high oxygen and energy demanding tissues, such as the brain, heart, liver, gastrointestinal tract, and ocular tissue, over a certain period of time (15)(16)(17)(18)(19)(20). The clinical characteristics commonly include blood pressure fluctuation, loss of memory function (declined cognitive function), absence of equilibrium function, headache, indigestion, decreased appetite, and so on (21)(22)(23)(24).…”

Intermittent hypoxia training effectively protects against cognitive decline caused by acute hypoxia exposure

“…Deyar reported that Air Force crew members exposed to a simulated HA of 20000 feet (equivalent to 6096 meters) for 15 minutes suffered from rapid learning and memory de cits, although visual and auditory memory were basically preserved with little change (Deyar et al, 2013). Short-term memory decreased following exposure to chronic hypoxia at 4400 m, and this effects was exacerbated as the altitude increased (Algaze et al, 2020). Therefore, the adverse effects of acute hypoxia exposure require e cient interventions to protect human cognitive functions.…”