title: Hematocrit increase by mental stress in hypertensive patients.
abstract: Hematocrit (Hct) changes during mental stress were studied in 21 patients with mild hypertension. A 10 min arithmetic stress test increased blood pressure from 129 +/- 2/80 +/- 2 mmHg (mean +/- SEM) to 167 +/- 5/98 +/- 3 mmHg, and heart rate from 64 +/- 2 to 81 +/- 3 (p less than 0.001). Concomitantly, a significant (p less than 0.001) increase in Hct was observed (from 41.5 +/- 0.7% to 42.2 +/- 0.8%), and increments of Hct (-0.1% to 2.2%) were significantly (r = 0.61, p less than 0.01) correlated with those of systolic blood pressure. Plasma levels of norepinephrine (NE), epinephrine (E) and atrial natriuretic peptide (ANP) also showed a significant increase after mental stress. All these changes disappeared after a 60 min recovery period. The results suggest that mental stress increases Hct promptly, which may be due to concomitant increases in plasma NE, E and ANP levels. Hct elevation resulting from mental stress may be clinically relevant, at least, in hypertensive patients who are at risk of occlusive vascular diseases.
authors.affiliation: Institute for Adult Diseases, Asahi Life Foundation, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kitahara
authors.forename: K
authors.initials: K
authors.lastname: Imataka
authors.forename: H
authors.initials: H
authors.lastname: Nakaoka
authors.forename: M
authors.initials: M
authors.lastname: Ishibashi
authors.forename: T
authors.initials: T
authors.lastname: Yamaji
authors.forename: J
authors.initials: J
authors.lastname: Fujii
mesh_terms: D000328:Adult; D000368:Aged; D009320:Atrial Natriuretic Factor / Q000097:blood; D001794:Blood Pressure; D002395:Catecholamines / Q000097:blood; D004906:Erythrocyte Count; D005260:Female; D006339:Heart Rate; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000503:physiopathology / Q000523:psychology; D008297:Male; D008875:Middle Aged; D013315:Stress, Psychological / Q000097:blood* / Q000503:physiopathology
chemical_list: D002395:Catecholamines; D006454:Hemoglobins; D009320:Atrial Natriuretic Factor