The present disclosure provides methods of treating hypoxia-induced cognitive impairment. Also disclosed are microbiome modulators, such as ketogenic-diet-suppressed bacterial species or antibiotics effective against a ketogenic-diet-boosted bacterial species, for use in treatment of cognitive impairment. The disclosure also provides methods of selecting a subject having hypoxia-induced cognitive impairment and methods of obtaining a prognostic indicator of hypoxia-induced cognitive impairment in a subject who receives a dosage of a microbiome modulator.