Food Liking-Based Diet Quality Indexes (DQI) Generated by Conceptual and Machine Learning Explained Variability in Cardiometabolic Risk Factors in Young Adults

The overall pattern of a diet (diet quality) is recognized as more important to health and chronic disease risk than single foods or food groups. Indexes of diet quality can be derived theoretically from evidence-based recommendations, empirically from existing datasets, or a combination of the two. We used these methods to derive diet quality indexes (DQI), generated from a novel dietary assessment, and to evaluate relationships with cardiometabolic risk factors in young adults with (n = 106) or without (n = 106) diagnosed depression (62% female, mean age = 21). Participants completed a liking survey (proxy for usual dietary consumption). Principle component analysis of plasma (insulin, glucose, lipids) and adiposity (BMI, Waist-to-Hip ratio) measures formed a continuous cardiometabolic risk factor score (CRFS). DQIs were created: theoretically (food/beverages grouped, weighted conceptually), empirically (grouping by factor analysis, weights empirically-derived by ridge regression analysis of CRFS), and hybrid (food/beverages conceptually-grouped, weights empirically-derived). The out-of-sample CRFS predictability for the DQI was assessed by two-fold and five-fold cross validations. While moderate consistencies between theoretically- and empirically-generated weights existed, the hybrid outperformed theoretical and empirical DQIs in cross validations (five-fold showed DQI explained 2.6% theoretical, 2.7% empirical, and 6.5% hybrid of CRFS variance). These pilot data support a liking survey that can generate reliable/valid DQIs that are significantly associated with cardiometabolic risk factors, especially theoretically- plus empirically-derived DQI.

A comparison of the genetic and clinical profile of men that respond and do not respond to the immediate antihypertensive effects of aerobic exercise

We compared the genetic and clinical profile of men who lower and do not lower blood pressure (BP) after acute aerobic exercise. Volunteers were 45 men (Mean ± SEM, 43.5 ± 1.5 yr) with high BP (145.7 ± 1.5/85.7 ± 1.1 mmHg). They completed three experiments: nonexercise control and two cycle exercise sessions at 40% and 60% peak oxygen consumption, and were then instrumented to an ambulatory BP monitor. Logistic regression determined the genetic and clinical profile of men who lowered BP after exercise (responders [ExR n = 36]); and those who did not (nonresponders [ExNR n = 9]). ExR had higher C-reactive protein (CRP), high-density lipoprotein (HDL), the metabolic syndrome, family history of hypertension, more renin-angiotensin system (RAS) common alleles, and α-adducin Trp(460) and endothelial nitric oxide synthase (ENOS) C(786) risk alleles. ExNR had lower CRP and HDL, did not have the metabolic syndrome and a family history of hypertension, had more RAS risk alleles, and had the α-adducin Gly460Gly and ENOS T786T genotypes. This model had a sensitivity of 97.1%, specificity of 75.0%, and accounted for 46.3%-74.4% of the BP response. These results suggest genetic and clinical information may eventually be used to characterize people who do and do not respond to exercise as antihypertensive therapy.

The metabolic syndrome and the immediate antihypertensive effects of aerobic exercise: a randomized control design

Background

The metabolic syndrome (Msyn) affects about 40% of those with hypertension. The Msyn and hypertension have a common pathophysiology. Exercise is recommended for their treatment, prevention and control. The influence of the Msyn on the antihypertensive effects of aerobic exercise is not known. We examined the influence of the Msyn on the blood pressure (BP) response following low (LIGHT, 40% peak oxygen consumption, VO₂peak) and moderate (MODERATE, 60% VO₂peak) intensity, aerobic exercise.

Methods

Subjects were 46 men (44.3 ± 1.3 yr) with pre- to Stage 1 hypertension (145.5 ± 1.6/86.3 ± 1.2 mmHg) and borderline dyslipidemia. Men with Msyn (n = 18) had higher fasting insulin, triglycerides and homeostasis model assessment (HOMA) and lower high density lipoprotein than men without Msyn (n = 28) (p < 0.01). Subjects consumed a standard meal and 2 hr later completed one of three randomized experiments separated by 48 hr. The experiments were a non-exercise control session of seated rest and two cycle bouts (LIGHT and MODERATE). BP, insulin and glucose were measured before, during and after the 40 min experiments. Subjects left the laboratory wearing an ambulatory BP monitor for the remainder of the day. Repeated measure ANCOVA tested if BP, insulin and glucose differed over time among experiments in men without and with the Msyn with HOMA as a covariate. Multivariable regression analyses examined associations among BP, insulin, glucose and the Msyn.

Results

Systolic BP (SBP) was reduced 8 mmHg (p < 0.05) and diastolic BP (DBP) 5 mmHg (p = 0.052) after LIGHT compared to non-exercise control over 9 hr among men without versus with Msyn. BP was not different after MODERATE versus non-exercise control between Msyn groups (p ≥ 0.05). The factors accounting for 17% of the SBP response after LIGHT were baseline SBP (β = -0.351, r² = 0.123, p = 0.020), Msyn (β = 0.277, r² = 0.077, p = 0.069), and HOMA (β = -0.124, r² = 0.015, p = 0.424). Msyn (r² = 0.096, p = 0.036) was the only significant correlate of the DBP response after LIGHT.

Conclusion

Men without the Msyn respond more favorably to the antihypertensive effects of lower intensity, aerobic exercise than men with the Msyn. If future work confirms our findings, important new knowledge will be gained for the personalization of exercise prescriptions among those with hypertension and the Msyn.

The alpha-adducin Gly460Trp polymorphism and the antihypertensive effects of exercise among men with high blood pressure

The alpha-adducin Gly460Trp polymorphism alters renal sodium transport and is associated with hypertension. Despite the immediate sodium- and volume-depleting effects of aerobic exercise, the influence of the alpha-adducin Gly460Trp polymorphism on PEH (postexercise hypotension) has not been studied. In the present study we examined the effects of the alpha-adducin Gly460Trp polymorphism on PEH among 48 men (42.6+/-1.6 years; mean+/-S.E.M.) with high BP (blood pressure; 144.0+/-1.7/84.7+/-1.1 mmHg). Subjects completed three experiments: non-exercise control and two cycle exercise sessions at 40% (light exercise) and 60% (moderate exercise) of maximal oxygen consumption. Subjects left the laboratory wearing an ambulatory BP monitor. PCR and restriction enzyme digestion determined the genotypes. No subjects had the Trp460Trp genotype due to the low frequency of 5% in the population. Repeated measure ANCOVA tested whether BP differed over time between experimental conditions and genotypes (Gly460Gly, n=36; Gly460Trp, n=12). Among Gly460Gly genotypes, SBP (systolic BP) was reduced by 5.2+/-1.4 mmHg after moderate exercise compared with non-exercise controls over 9 h (P<0.01). Among Gly460Trp genotypes, SBP was lowered by 7.8+/-2.3 mmHg; after light exercise compared with non-exercise controls over 9 h (P<0.05). The SBP reductions after light exercise (0.6+/-1.3 compared with 7.8+/-2.3 mmHg; P<0.05) but not moderate exercise (5.2+/-1.4 compared with 3.8+/-2.4 mmHg; P> or =0.05) differed between the Gly460Gly and Gly460Trp genotypes respectively. Men with Gly460Gly had a reduced SBP after moderate exercise, whereas men with Gly460Trp had a reduced SBP after light exercise. However, only the SBP reductions after light exercise differed between genotypes. Our findings indicate that the alpha-adducin Gly460Trp genotype may be useful in identifying men who have a reduced BP after lower intensity aerobic exercise.

Dietary calcium intake and renin angiotensin system polymorphisms alter the blood pressure response to aerobic exercise: a randomized control design

Background

Dietary calcium intake and the renin angiotensin system (RAS) regulate blood pressure (BP) by modulating calcium homeostasis. Despite similar BP regulatory effects, the influence of dietary calcium intake alone and combined with RAS polymorphisms on the BP response following acute aerobic exercise (i.e., postexercise hypotension) has not been studied. Thus, we examined the effect of dietary calcium intake and selected RAS polymorphisms on postexercise hypotension.

Methods

Subjects were men (n = 50, 43.8 ± 1.3 yr) with high BP (145.3 ± 1.5/85.9 ± 1.1 mm Hg). They completed three experiments: non-exercise control and two cycle bouts at 40% and 60% of maximal oxygen consumption (VO₂max). Subjects provided 3 d food records on five protocol-specific occasions. Dietary calcium intake was averaged and categorized as low (<880 mg/d = LowCa) or high (≥ 880 mg/d = HighCa). RAS polymorphisms (angiotensin converting enzyme insertion/deletion, ACE I/D; angiotensin II type 1 receptor, AT₁R A/C) were analyzed with molecular methods. Genotypes were reduced from three to two: ACE II/ID and ACE DD; or AT₁R AA and AT₁R CC/AC. Repeated measure ANCOVA tested if BP differed among experiments, dietary calcium intake level and RAS polymorphisms.

Results

Systolic BP (SBP) decreased 6 mm Hg after 40% and 60% VO₂max compared to non-exercise control for 10 h with LowCa (p < 0.01), but not with HighCa (p ≥ 0.05). Under these conditions, diastolic BP (DBP) did not differ between dietary calcium intake levels (p ≥ 0.05). With LowCa, SBP decreased after 60% VO₂max versus non-exercise control for 10 h among ACE II/ID (6 mm Hg) and AT₁R AA (8 mm Hg); and by 8 mm Hg after 40% VO₂max among ACE DD and AT₁R CC/CA (p < 0.01). With HighCa, SBP (8 mm Hg) and DBP (4 mm Hg) decreased after 60% VO₂max compared to non-exercise control for 10 h (p < 0.05), but not after 40% VO₂max (p ≥ 0.05).

Conclusion

SBP decreased after exercise compared to non-exercise control among men with low but not high dietary calcium intake. Dietary calcium intake interacted with the ACE I/D and AT₁R A/C polymorphisms to further modulate postexercise hypotension. Interactions among dietary calcium intake, exercise intensity and RAS polymorphisms account for some of the variability in the BP response to exercise.

Peak systolic blood pressure on a graded maximal exercise test and the blood pressure response to an acute bout of submaximal exercise

Blood pressure (BP) is immediately reduced after aerobic exercise (postexercise hypotension [PEH]). Whether peak systolic BP on a maximal graded exercise stress test (GEST) relates to PEH is not known. This study examined associations between peak systolic BP on a GEST and PEH. Subjects were 50 men (mean +/- SEM age 43.8 +/- 1.3 years) with elevated BP (145.3 +/- 1.5/85.9 +/-1.1 mm Hg). Men completed a GEST and 3 experiments: nonexercise control and 2 cycle bouts at 40% (LIGHT) and 60% (MODERATE) of maximal oxygen consumption. After the experiments, subjects left the laboratory wearing ambulatory BP monitors. Peak systolic BP on a GEST was categorized into tertiles: low (n = 17, 197.4 +/- 2.0 mm Hg), medium (n = 16, 218.4 +/- 1.4 mm Hg), and high (n = 17, 248.9 +/- 2.8 mm Hg). Repeated-measures analysis of variance tested if BP differed over time and among experimental conditions and peak systolic BP groups. In men with high peak systolic BP, systolic BP was reduced by 7.3 +/- 2.6 mm Hg after LIGHT and by 5.0 +/- 2.2 mm Hg after MODERATE compared with nonexercise control over 10 hours, with the more apparent effects seen after LIGHT (p <0.05). In men with low peak systolic BP, systolic BP was reduced by 6.3 +/- 2.3 mm Hg after MODERATE compared with nonexercise control over 10 hours (p <0.05). In men with medium peak systolic BP, systolic BP was not different after exercise compared with nonexercise control over 10 hours (p >or=0.05). Men with high peak systolic BP had decreased systolic BP to the greatest extent after LIGHT, whereas men with low peak systolic BP reduced systolic BP after MODERATE. In conclusion, the findings of this study suggest that peak systolic BP on a GEST may be used to characterize which men with hypertension will have decreased systolic BP after acute submaximal aerobic exercise.

The influence of short and long duration on the blood pressure response to an acute bout of dynamic exercise

BACKGROUND

The minimum duration of exercise needed to acutely lower blood pressure (BP) has not been established. The purpose of this study is to compare the effects of short and long duration on the BP response to a session of aerobic exercise.

METHODS

Subjects were 45 men (mean +/- SEM, 43.4 +/- 1.5 years) with elevated BP (144.6 +/- 1.6/85.2 +/- 1.1 mm Hg). Using a parallel design, men were randomly assigned to 40% (LITE, n = 23) or 60% (MOD, n = 22) of maximal oxygen consumption. Following assignment, they completed 3 experiments: a no-exercise control, and a 15-minute SHORT and 30-minute LONG cycle bout. Subjects left the laboratory wearing an ambulatory BP monitor. Repeated measure analysis of variance tested if BP differed among experimental conditions (no-exercise control, LONG, and SHORT) and over time within groups (LITE and MOD).

RESULTS

For 9 hours, systolic BP increased from baseline after all conditions (P < .001); however, systolic BP was reduced by 5.6 +/- 2.0 and 4.3 +/- 1.6 mm Hg after SHORT and LONG with LITE, and 4.1 +/- 1.6 and 4.9 +/- 1.9 mm Hg with MOD, respectively, compared with no-exercise control (P < .05). For 9 hours, diastolic BP (DBP) decreased from baseline after all conditions (P < .001). DBP was reduced by 2.1 +/- 1.0 and 3.6 +/- 1.4 mm Hg after SHORT and LONG with MOD for 3 hours (P < .05), and average DBP was lower by 2.4 +/- 1.0 mm Hg after LONG with LITE for 9 hours versus no-exercise control (P < .05).

CONCLUSIONS

The immediate BP-lowering effects of short-duration, lower intensity exercise are comparable to those of higher amounts of exercise. Additional investigation is needed to better quantify the dose of exercise needed to lower BP.

RAAS polymorphisms alter the acute blood pressure response to aerobic exercise among men with hypertension

Limited evidence suggests renin-angiotensin-aldosterone system (RAAS) polymorphisms alter the blood pressure (BP) response to aerobic exercise training. We examined if RAAS polymorphisms influenced postexercise hypotension in men with high normal to Stage 1 hypertension. Forty-seven men (44.2+/-1.4 years, 145.1+/-1.6/85.5+/-1.1 mmHg) randomly completed three experiments: seated rest (control) and two cycle exercise bouts at 40% (LITE) and 60% (MOD) of maximal oxygen consumption. Ambulating BP was measured for 14 h after each experiment. RAAS polymorphisms associated with hypertension (i.e. angiotensin converting I enzyme, ACE I/D; angiotensin II type 1 receptor, AT1R A/C; and intron 2 of aldosterone synthase, Int2 W/C) were analyzed using polymerase chain reaction and restriction enzyme digestion. Repeated measure ANOVA tested if BP differed between experimental conditions by RAAS genotypes. Compared to men with 0-2 variant alleles, men with > or =3 combined RAAS variant alleles had lower average systolic BP (SBP) (P=0.030) and lower average diastolic BP (DBP) (P=0.009) for 14 h only after LITE. In contrast, average BP was not different for MOD and control between RAAS variant allele groups over this time period (P> or =0.05). LITE reduced BP in men with > or =3 variant RAAS alleles for 14 h, whereas MOD had no influence on BP in these men. In order to optimally prescribe exercise for its BP lowering benefits in those with hypertension, additional knowledge of how genetic variation affects the BP response to exercise is needed.

Exercise intensity alters postexercise hypotension

OBJECTIVE

Blood pressure (BP) is immediately lowered after a session of dynamic exercise, e.g. postexercise hypotension (PEH). The optimal exercise intensity needed to evoke PEH has not been established. We examined the effect of light (LITE) and moderate (MOD) exercise intensity on PEH.

DESIGN

Subjects were 49 men (mean +/- SEM, 43.8 +/- 1.4 years) with high normal to stage 1 hypertension (145.0 +/- 1.5/85.8 +/- 1.1 mmHg). Men randomly completed three blinded experiments: a control session and two cycle exercise bouts, one at 40% (LITE) and the other at 60% (MOD) of maximal oxygen consumption.

METHODS

Experiments began with a baseline period and were conducted at the same time of day and separated by >/= 2 days. Subjects wore an ambulatory BP monitor after the experiments. Repeated measure analysis of variance (ANOVA) tested if BP and heart rate differed over time and between experimental conditions. Multivariate regression tested factors related to the BP response.

RESULTS

For 9 h after all experiments, average awake systolic blood pressure (SBP) increased and diastolic blood pressure (DBP) decreased compared with baseline (P < 0.001). Average awake SBP increased up to 6.9 mmHg less (P < 0.001) and DBP decreased 2.6 mmHg more (P < 0.05) after exercise versus control. For 5 h, PEH was greater after MOD; but over the course of 9 h, LITE was as effective as MOD in eliciting PEH. Baseline BP was the primary factor explaining the BP response (beta = -0.434 to -0.718, r = 0.096-0.295).

CONCLUSIONS

LITE and MOD evoked PEH throughout the daytime hours. Lower intensity dynamic exercise such as walking, contributes to BP control in men with hypertension.