Defensive coping and essential amino acid markers as possible predictors for structural vascular disease in an African and Caucasian male cohort: the SABPA study

Abstract

Defensive coping (DefS), oxidative stress, inflammation, and related amino acids (phenylalanine [Phe] and tyrosine [Tyr]) have been implicated in cardiovascular disease. This study assessed whether inflammation, oxidative stress, changes in essential amino acids, and altered coping strategies are correlated with subclinical vascular changes in African (n = 82) and Caucasian (n = 100) men from the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study. The Coping Strategy Indicator questionnaire identified DefS participants. Ambulatory blood pressure (BP) was monitored for 24 h, whereas carotid intima media thickness (CIMT) and cross-sectional wall area (CSWA) were determined ultrasonically. Essential amino acids were analyzed with a liquid chromatography tandem mass spectrometry method. Oxidative-inflammatory markers were measured by spectrophotometry. African men had poorer health than Caucasian men, including higher alcohol abuse, elevated BP, abdominal obesity, physical inactivity, and elevated inflammation. Phe (p < .001) and Phe/Tyr ratio (p = .006) as well as CIMT (p = .032) were higher in African men. DefS African men had higher levels of Phe (p = .002) and Phe/Tyr (p = .009) compared to DefS Caucasian men; these differences were not observed in non-DefS men. Systolic BP and inflammation (C-reactive protein) were positively associated with left (L-) CSWA, while Phe/Tyr was negatively associated with L-CSWA in DefS African men. African males presented with elevated Phe and Phe/Tyr ratio, catecholamine precursors, worsening during DefS—possibly driven by inflammation and BP contributing to structural vascular abnormalities