Physiological Adaptation Buffers Personality-Linked Psychopathology Under High-Altitude Hypoxia

High-altitude hypoxia imposes persistent physiological stress that may influence psychological health. While personality traits such as neuroticism are known predictors of psychological symptom burden, little is known about whether physiological adaptation-specifically hematologic compensation-is associated with personality-related differences in psychological symptoms under chronically hypoxic conditions.

Healthy adults residing at high altitude completed the Chinese version of the Big Five Inventory-2 and provided blood data for RBC, HGB, and HCT. k-Means clustering identified two personality clusters (high vs. low neuroticism) and three hematologic compensation clusters (low, medium, and high). Psychological symptoms across nine domains were assessed using the Symptom Checklist-90 (SCL-90), a 90-item self-report inventory designed to assess a broad range of psychological symptoms.

A 2 (personality) × 3 (hematologic compensation) multivariate general linear model revealed no significant interactions on most SCL-90 dimensions after controlling for gender, age, and hypoxic exposure time, except for a significant interaction on the SCL-90 psychoticism dimension (F(2, 120) = 4.026, p = 0.02, ${\eta }_p^2$  = 0.063). Simple-effect analysis showed that in the high hematologic compensation group, individuals in the high-neuroticism cluster reported lower SCL-90 psychoticism scores than those in the low-neuroticism cluster.

These findings provide preliminary evidence for a domain-specific interaction between personality profiles and hematologic compensation on the SCL-90 psychoticism dimension under chronic high-altitude hypoxia. Importantly, this dimension reflects self-reported subclinical psychoticism-related tendencies rather than clinical psychosis. Because this interaction was not observed across most SCL-90 dimensions, the results should be interpreted cautiously and require replication.