Sympathetic reactivity in young women with a family history of hypertension

Abstract

Young adults with a family history of hypertension (+FH) have increased risk of developing hypertension. Furthermore, the blood pressure (BP) response to sympathoexcitatory stimuli in young adults can predict the future development of hypertension. Therefore, we hypothesized young women with a +FH would have exaggerated cardiovascular and sympathetic reactivity compared with young women without a family history of hypertension (-FH). Beat-by-beat mean arterial pressure (MAP) and muscle sympathetic nerve activity (MSNA) were measured in 14 women +FH (22 ± 1 yr, 21 ± 1 kg/m(2), MAP 80 ± 2 mmHg) and 15 women -FH (22 ± 1 yr, 22 ± 1 kg/m(2), MAP 78 ± 2 mmHg) during acute sympathoexcitatory maneuvers: cold pressor test, 2 min of isometric handgrip (HG) exercise at 30% of maximal voluntary contraction, and 3 min of postexercise ischemia (PEI; isolated activation of the skeletal muscle metaboreflex). During cold pressor test, the increase in BP was greater in women +FH (ΔMAP: +FH 16 ± 2 vs. -FH 11 ± 1 mmHg, P < 0.05), which was accompanied by an exaggerated increase in MSNA (ΔMSNA: +FH 17 ± 2 vs. -FH 8 ± 2 burst/min, P < 0.05). The increase in BP was greater in +FH during the last minute of HG (ΔMAP: +FH 23 ± 3 vs. -FH 12 ± 1 mmHg, P < 0.05) and during PEI (ΔMAP: +FH 17 ± 3 vs. -FH 9 ± 2 mmHg, P < 0.05). Similarly, the increase in MSNA was greater in +FH during both HG (ΔMSNA: +FH 12 ± 2 vs. -FH 6 ± 2 burst/min, P < 0.05) and PEI (ΔMSNA: +FH 16 ± 2 vs. -FH 4 ± 2 burst/min, P < 0.05). These data demonstrate that +FH women have greater BP and sympathetic reactivity compared with -FH women.

Sympathetic neural reactivity to mental stress in offspring of hypertensive parents: 20 years revisited

“…These differences across studies are likely due to a number of methodological details and higher degree of interindividual variability. In contrast to the reported variability of BMI and resting BP in subjects with and without FHH, there appears to be consistency across laboratories regarding (3,18,22,26,35,44). In one study (31), subjects with extreme and complicated FHH (i.e., concomitant grade III or IV retinopathy) demonstrated higher resting MSNA than subjects without FHH; however, the impact of the underlying retinopathy in that study remains unclear (31).…”

“…Greaney et al (18) recently reported a greater MSNA reactivity to cold pressor test in adults with FHH than those without FHH. However, others have reported that MSNA reactivity to cold pressor test was not significantly influenced by FHH (3) or was actually heightened in subjects without FHH compared with those with FHH (26).…”

“…However, others have reported that MSNA reactivity to cold pressor test was not significantly influenced by FHH (3) or was actually heightened in subjects without FHH compared with those with FHH (26). In contrast, two independent studies report greater MSNA reactivity to handgrip exercise in subjects with FHH than those without FHH (18,30). So while evidence is accumulating to support a MSNA reactivity hypothesis, particularly during certain laboratory stressors, more rigorous studies are necessary.…”

“…Given the large interindividual variability of MSNA responsiveness to mental stress (7) and the recent calls for increased scientific rigor and reproducibility (12), we conducted a traditional test-retest study and reported significant reproducibility of MSNA responses to mental stress, as well as cold pressor test, within a single laboratory visit and across laboratory visits separated by ϳ1 mo (15). Interestingly, Greaney et al (18) recently reported that MSNA reactivity to cold pressor test was augmented in subjects with FHH.…”

Rapid onset pressor response to exercise in young women with a family history of hypertension

“…There are emerging data indicating aberrant neural cardiovascular control in young adults with a family history of hypertension (+FH; Greaney et al . ; Fonkoue et al . ).…”