Differential effects of bariatric surgery and lifestyle interventions on plasma levels of Lp(a) and fatty acids.

BACKGROUND: Limited evidence suggests that surgical and non-surgical obesity treatment differentially influence plasma Lipoprotein (a) [Lp(a)] levels. Further, a novel association between plasma arachidonic acid and Lp(a) has recently been shown, suggesting that fatty acids are a possible target to influence Lp(a). Here, the effects of bariatric surgery and lifestyle interventions on plasma levels of Lp(a) were compared, and it was examined whether the effects were mediated by changes in plasma fatty acid (FA) levels. METHODS: The study includes two independent trials of patients with overweight or obesity. Trial 1: Two-armed intervention study including 82 patients who underwent a 7-week low energy diet (LED), followed by Roux-en-Y gastric bypass and 52-week follow-up (surgery-group), and 77 patients who underwent a 59-week energy restricted diet- and exercise-program (lifestyle-group). Trial 2: A clinical study including 134 patients who underwent a 20-week very-LED/LED (lifestyle-cohort). RESULTS: In the surgery-group, Lp(a) levels [median (interquartile range)] tended to increase in the pre-surgical LED-phase [17(7-68)-21(7-81)nmol/L, P = 0.05], but decreased by 48% after surgery [21(7-81)-11(7-56)nmol/L, P < 0.001]. In the lifestyle-group and lifestyle-cohort, Lp(a) increased by 36%[14(7-77)-19(7-94)nmol/L, P < 0.001] and 14%[50(14-160)-57(19-208)nmol/L, P < 0.001], respectively. Changes in Lp(a) were independent of weight loss. Plasma levels of total saturated FAs remained unchanged after surgery, but decreased after lifestyle interventions. Arachidonic acid and total n-3 FAs decreased after surgery, but increased after lifestyle interventions. Plasma FAs did not mediate the effects on Lp(a). CONCLUSION: Bariatric surgery reduced, whereas lifestyle interventions increased plasma Lp(a), independent of weight loss. The interventions differentially influenced changes in plasma FAs, but these changes did not mediate changes in Lp(a). TRIAL REGISTRATION: Trial 1: Clinicaltrials.gov NCT00626964. Trial 2: Netherlands Trial Register NL2140 (NTR2264).

Effect of aerobic exercise intensity on health-related quality of life in severe obesity: a randomized controlled trial.

BACKGROUND: Aerobic exercise is an important part of obesity treatment and may improve health-related quality of life (HRQOL). The objective of this study was to compare the effect of two different exercise programs on health-related quality of life in patients with severe obesity. METHODS: This was a single-center, open-label, randomized, parallel-group study comparing the effects of a 24-week moderate-intensity continuous training (MICT) program and a combined high-intensity interval training program with MICT (HIIT/MICT). The primary objective (specified secondary outcome) was to assess HRQOL by using the general health dimension of the Short Form Health Survey (SF-36). The secondary objectives were to assess other dimensional SF-36 scores, the impact of weight on the physical and psychosocial aspects of quality of life (IWQOL-Lite), and the burden of obesity-specific weight symptoms (WRSM). RESULTS: 73 patients were enrolled and reported patient reported outcome measures, with 71 patients (55% females) allocated to either MICT (n = 34) or HIIT/MICT (n = 37). In the intention-to-treat analysis, general health scores increased between baseline and 24-week follow-up in both the HIIT/MICT group and the MICT group, with a mean change of 13 (95% CI 6-21) points and 11 (95% CI 5-17) points, respectively, with no difference between the groups. The effect sizes of these changes were moderate. The vitality and social functioning scores of SF-36, and the physical function and self-esteem scores of IWQOL-Lite increased moderately in both groups, with no difference between groups. The tiredness, back pain, and physical stamina scores based on WRSM showed moderate to strong changes in both the groups. CONCLUSIONS: Patients who had completed a combined HIIT/MICT program did not experience larger improvements in general health compared with those completing a clean 24-week MICT program. Exercise may confer general health benefits independent of intensity. TRIALS REGISTRATION: Regional Committees for Medical and Health Research Ethics south east, Norway, October 23, 2013 (identifier: 2013/1849) and ClinicalTrials.gov December 8, 2014 (identifier: NCT02311738).

Effect of Aerobic Exercise Intensity on Energy Expenditure and Weight Loss in Severe Obesity-A Randomized Controlled Trial.

OBJECTIVE: This study aimed to compare the effects of two aerobic exercise programs of different intensities on energy expenditure. METHODS: This was a single-center randomized controlled trial of patients with severe obesity allocated to a 24-week moderate-intensity continuous training (MICT) program or a combined MICT with high-intensity interval training (HIIT/MICT) program. The primary outcome was energy expenditure during exercise (EEDE). Secondary outcomes included resting metabolic rate, cardiorespiratory fitness, and body composition. RESULTS: A total of 82 (56% females) patients were screened, and 71 (55% females) patients were allocated to HIIT/MICT (n = 37) or MICT (n = 34). Per-protocol analysis showed that EEDE increased by 10% (95% CI: 3%-17%) in the HIIT/MICT group (n = 16) and 7.5% (95% CI: 4%-10%) in the MICT group (n = 24), with no differences between groups. In the 8- to 16- week per-protocol analysis, the HIIT/MICT group had a significantly larger increase in EEDE compared with the MICT group. Resting metabolic rate remained unchanged in both groups. HIIT/MICT and MICT were associated with significant weight loss of 5 kg and 2 kg, respectively. CONCLUSIONS: Patients completing a 24-week combined HIIT/MICT program did not achieve a higher EEDE compared with those who completed a 24-week MICT program. The HIIT/MICT group experienced, on average, a 3-kg-larger weight loss than the MICT group.

Gastric bypass surgery is associated with reduced subclinical myocardial injury and greater activation of the cardiac natriuretic peptide system than lifestyle intervention.

AIMS: Morbid obesity is a risk factor for cardiovascular disease. The relative effects of Roux-en-Y gastric bypass surgery (GBS) and intensive lifestyle intervention (ILI) on subclinical myocardial injury, the activity of the cardiac natriuretic system, and systemic inflammation remain unclear. METHODS: In a 59-week non-randomized clinical trial that included 131 patients with morbid obesity, we compared the effects ofGBS and ILI on concentrations of cardiac troponin T (cTnT) and I (cTnI), N-terminal pro-B-type natriuretic peptide (NT-proBNP) and C-reactive protein (CRP). RESULTS: In the GBS and ILI group, median body mass index (BMI) was reduced by 14.4 kg/m2 versus 3.9 kg/m2, respectively (p value < 0.001). Cardiac troponins decreased after GBS, p = 0.014 (cTnT) and p = 0.065 (cTnI) and increased significantly in those treated with ILI (p values ≤ 0.021) (between-group differences for deltas: p ≤ 0.003). NT-proBNP increased in both groups, but significantly more in the GBS than in the ILI group (between-group differences for deltas: p = 0.008). CRP decreased significantly within the GBS and the ILI group, with this change significantly greater in the GBS group (between-group differences for deltas p < 0.001). The dominating mediator of the biomarker changes was weight loss. Prior coronary artery disease and diabetes were predictive of the magnitude of the changes in cTnI and NT-proBNP, respectively. CONCLUSION: Compared to ILI, GBS was associated with reduced subclinical myocardial injury and systemic inflammation, and enhancement of the cardiac natriuretic peptide system. The biomarker changes were predominantly mediated by weight loss.

Associations between cardiorespiratory fitness and weight loss in patients with severe obesity undergoing an intensive lifestyle intervention program: retrospective cohort study.

BACKGROUND: To assess the association between cardiorespiratory fitness (CRF) and weight changes in treatment seeking patients with severe obesity who underwent a 1-year intensive lifestyle intervention (ILI) program. METHODS: Retrospective cohort study conducted at a tertiary care outpatient rehabilitation center from November 1, 2013 through January 1, 2017. CRF was measured as maximal oxygen consumption during a maximal oxygen uptake (VO2max) test on a treadmill or bicycle at baseline and after 3 months. RESULTS: A total of 180 patients had a baseline mean (SD) BMI 41.1 (4.8) kg/m2 and CRF of 79.4 (14.9) mL·kg-0.75·min- 1. Patients with a baseline CRF above median achieved a greater 3-month and 1-year weight loss compared with patients with CRF below median; mean (95% CI) 2.5 kg (1.3, 3.8) and 4.0 kg (0.8, 7.2), respectively. In addition, patients with 3-month changes of CRF above median had 4.0 kg (0.9, 7.1) greater weight loss at 1-year follow-up than those below median. CONCLUSIONS: Among patients with severe obesity who underwent a 1-year ILI program, higher baseline CRF was associated with significantly larger weight loss after 3 months and 1 year. In addition, those with higher initial 3-month CRF changes had greater weight loss at 1 year. TRIAL REGISTRATION: Retrospectively registered in Regional Committees for Medical and Health Research Ethics (REC) south east September 22, 2016 (2016/1414) and clinicaltials.gov August 13, 2018 (identifier: NCT03593798 ).

Effects of intensive lifestyle intervention and gastric bypass on aortic stiffness: a 1-year nonrandomized clinical study.

OBJECTIVE: To compare the long-term effects of Roux-en-Y gastric bypass (GBS) and intensive lifestyle intervention (ILI) on aortic stiffness. METHODS: Nonrandomized clinical trial. Aortic stiffness was assessed by carotid-femoral pulse wave velocity (cf PWV) using high-fidelity applanation tonometry. RESULTS: A total of 159 treatment-seeking morbidly obese patients were included, 82 (54 females) in the GBS-group and 77 (48 females) in the ILI-group. Participants in the GBS-group were younger (42.0 ± 9.9 vs. 46.4 ± 10.5 years), heavier (BMI 45.7 ± 5.3 vs. 42.0 ± 4.9 kg/m(2) ), and had lower systolic pressure (137 ± 19 vs. 145 ± 18 mm Hg) and pulse pressure (57 ± 16 vs. 65 ± 17 mm Hg), all P ≤ 0.006. Mean (SD) cf PWV at baseline was 8.6 ± 1.7 m/s in the GBS-group and 8.6 ± 1.9 m/s in the ILI-group, P = 0.959. At follow-up, mean (95% CI) weight loss was larger in the GBS-group than in the ILI-group -43.3 (-46.0 to -40.7) vs. -12.1 (-14.6 to -9.6) kg, P < 0.001. The mean change in cf PWV was -0.02 (-0.31 to 0.27) m/s in the GBS-group and 0.03 (-0.28 to 0.33) m/s in the ILI-group, both P ≥ 0.412; adjusted between-group difference (ANCOVA) 0.05 (-0.40 to 0.49) m/s, P = 0.836. The adjusted regression analysis showed that weight loss was associated with increased cf PWV in the GBS-group. CONCLUSIONS: GBS and ILI had no significant long-term effects on aortic stiffness in treatment-seeking morbidly obese individuals.