Associations of changes in physical activity and sedentary time with weight recurrence after bariatric surgery: a 5-year prospective study.

BACKGROUND: Increasing physical activity and limiting sedentary time may minimize weight recurrence after bariatric surgery. However, few studies have evaluated potential associations of objectively-measured physical activity and sedentary time with post-surgical weight recurrence over time. AIMS: To evaluate associations of change in physical activity and sedentary time with weight recurrence after bariatric surgery. METHODS: Participants from the Oslo Bariatric Surgery Study, a prospective cohort study, wore an ActiGraph monitor for seven days at 1- and 5 years after surgery to assess daily physical activity and sedentary time. Participants' weight was measured at in-person clinic visits. Chi-square Test and Paired-samples T-test evaluated group differences and change over time, while Pearson's Correlation, multiple logistic and linear regression investigated associations between variables. RESULTS: Five years after surgery 79 participants (70.5% response rate, 81% female) (mean (sd) age: 54.0 (±9.3), BMI: 32.1 (±4.7)) had valid monitor data. Participants increased their sedentary time (71.4 minutes/day (95% CI: 54.2-88.6, p = <0.001)) and reduced daily steps (-1411.1 (95% CI: 737.8-208.4), p = <0.001), light physical activity (-54.1 min/day (95% CI: 40.9-67.2, p = <0.001)), and total physical activity (-48.2 (95% CI: 34.6-63.3), p = <0.001) from 1- to 5 years after surgery. No change was found for moderate-to-vigorous intensity physical activity. No associations were found between changes in steps, physical activity or sedentary time and weight recurrence. CONCLUSION: Participants increased sedentary time and decreased light- and total physical activity between 1- and 5 years post-surgery. Overall, changes in physical activity and sedentary time were not associated with weight recurrence. Interventions to help patients increase physical activity and limit sedentary time after bariatric surgery are needed.

Intervention-related increases in preoperative physical activity are maintained 6-months after Bariatric surgery: results from the bari-active trial.

Higher preoperative physical activity (PA) strongly predicts higher post-operative PA in bariatric surgery (BS) patients, providing rationale for preoperative PA interventions (PAIs). However, whether PAI-related increases can be maintained post-operatively has not been examined. This study compared PA changes across pre- (baseline, post-intervention) and post-operative (6-month follow up) periods in participants randomized to 6 weeks of preoperative PAI or standard care control (SC). Of 75 participants initially randomized, 36 (PAI n=22; SC n=14) underwent BS. Changes in daily bout-related (⩾10-min bouts) moderate-to-vigorous PA (MVPA) and steps were assessed via the SenseWear Armband monitor. PAI received weekly counseling to increase walking exercise. Retention (86%) at post-operative follow up was similar between groups. Intent-to-treat analyses showed that PAI vs SC had greater increases across time (baseline, post-intervention, follow up) in bout-related MVPA minutes/day (4.3±5.1, 26.3±21.3, 28.7±26.3 vs 10.4±22.9, 11.4±16.0, 18.5±28.2; P=0.013) and steps/day (5163±2901, 7950±3286, 7870±3936 vs 5163±2901, 5601±3368, 5087±2603; P<0.001). PAI differed from SC on bout-related MVPA at post-intervention (P=0.016; d=0.91), but not follow up (P=0.15; d=0.41), and steps at post-intervention (P=0.031; d=0.78) and follow up (P=0.024; d=0.84). PAI participants maintained preoperative PA increases post-operatively. Findings support preoperative PAIs and research to test whether PA changes can be sustained and influence surgical outcomes beyond the initial post-operative period.

Salivary habituation to food stimuli in successful weight loss maintainers, obese and normal-weight adults.

OBJECTIVE: Research shows that slower habituation of salivary responses to food stimuli is related to greater energy intake and that obese (Ob) individuals habituate slower than those of normal weight (NW). No study has examined habituation rates in weight loss maintainers (WLMs) who have reduced from obese to normal weight, relative to those who are Ob or NW. DESIGN: Salivation to two baseline water trials and 10 lemon-flavored lollipop trials were studied in 14 WLMs, 15 Ob and 18 NW individuals comparable in age, gender and ethnicity. Linear mixed models were used to compare WLMs with Ob and NW groups. RESULTS: Salivation in the WLM and NW groups decreased significantly (for both P <0.005) across trials, indicative of habituation. Salivary responses in the Ob group did not habituate (P=0.46). When compared with Ob group, WLMs showed a quicker reduction in salivation (P<0.05). WLM and NW groups did not differ in habituation rate (P=0.49). CONCLUSIONS: WLMs have habituation rates that are comparable to NW individuals without previous history of obesity, and show quicker habituation than those who are currently obese. These results suggest that physiological responses to food may 'normalize' with successful weight loss maintenance.

Weight-loss maintenance in successful weight losers: surgical vs non-surgical methods.

OBJECTIVE: As large weight losses are rarely achieved through any method except bariatric surgery, there have been no studies comparing individuals who initially lost large amounts of weight through bariatric surgery or non-surgical means. The National Weight Control Registry (NWCR) provides a resource for making such unique comparisons. This study compared the amount of weight regain, behaviors and psychological characteristics in NWCR participants who were equally successful in losing and maintaining large amounts of weight through either bariatric surgery or non-surgical methods. DESIGN: Surgical participants (n=105) were matched with two non-surgical participants (n=210) on gender, entry weight, maximum weight loss and weight-maintenance duration, and compared prospectively over 1 year. RESULTS: Participants in the surgical and non-surgical groups reported having lost approximately 56 kg and keeping > or =13.6 kg off for 5.5+/-7.1 years. Both groups gained small but significant amounts of weight from registry entry to 1 year (P=0.034), but did not significantly differ in magnitude of weight regain (1.8+/-7.5 and 1.7+/-7.0 kg for surgical and non-surgical groups, respectively; P=0.369). Surgical participants reported less physical activity, more fast food and fat consumption, less dietary restraint, and higher depression and stress at entry and 1 year. Higher levels of disinhibition at entry and increased disinhibition over 1 year were related to weight regain in both groups. CONCLUSIONS: Despite marked behavioral differences between the groups, significant differences in weight regain were not observed. The findings suggest that weight-loss maintenance comparable with that after bariatric surgery can be accomplished through non-surgical methods with more intensive behavioral efforts. Increased susceptibility to cues that trigger overeating may increase risk of weight regain regardless of initial weight-loss method.

Successful weight loss maintainers use health-tracking smartphone applications more than a nationally representative sample: comparison of the National Weight Control Registry to Pew Tracking for Health.

OBJECTIVE: The objective of this paper is to evaluate successful weight loss maintainers' use of self-monitoring technology. METHODS: National Weight Control Registry (NWCR) participants, who maintained a ≥13.6 kg weight loss for ≥1 year, completed an online survey about self-monitoring technology use. The NWCR sample (n = 794) was compared with a demographically similar subsample of 833 individuals answering the same questions in the Pew Tracking for Health Survey. RESULTS: The NWCR had higher rates of tracking weight, diet or exercise using any modality (92.8% vs. 71.3%), on a regular basis (67.4% vs. 41.3%), and frequency of updating records, compared with Pew (ps < .01). Smartphone ownership was higher in NWCR participants (80.2% vs. 52.8%, p < .001), and NWCR smartphone owners had 23.1 times greater odds for using diet, food or calorie counter apps (58.9% vs. 5.9%) and 15.5 times greater odds for using weight monitoring apps (31.7% vs. 3.0%; all ps < .01). Pew respondents more often changed their behaviour based on their tracking data (ps < .01). CONCLUSION: Use of self-monitoring technology is common in weight loss maintainers: more so than in a nationally representative sample. However, the national sample more often changed their behaviour based on tracking data, perhaps suggesting that weight loss maintainers could derive additional benefit from technology they are already using.

Weight loss and frequency of body-weight self-monitoring in an online commercial weight management program with and without a cellular-connected 'smart' scale: a randomized pilot study.

Objective: Evaluate the effects of an online commercial weight management program, with and without provision of a 'smart' scale with instructions to weigh daily and weekly tailored feedback, on weight loss and the frequency of body-weight self-monitoring. Methods: Participants (N = 92; body mass index 27-40 kg/m2) were randomized to 6 months of no-cost access to the Weight Watchers Online (WWO) platform alone, or enhanced with a cellular-connected 'smart' scale, instructions to weigh daily and weekly pre-scripted email feedback (Weight Watchers Online Enhanced [WWO-E]). The number of days that weight was self-monitored (via 'smart' scale in WWO-E and manually in WWO) was recorded automatically across the 6-month trial. Objective weight was measured at baseline, 3 and 6 months. Results: While both groups achieved statistically significant weight loss, mean ± standard error weight loss did not differ between WWO-E and WWO at 3 months (5.1 ± 0.6 kg vs. 4.0 ± 0.7 kg, respectively; p = 0.257) or 6 months (5.3 ± 0.6 kg vs. 3.9 ± 0.7 kg, respectively; p = 0.116). However, a greater proportion of WWO-E lost ≥5% of initial body weight at 3 months (52.2% vs. 28.3%; p = 0.033), but not 6 months (43.5% vs. 30.4%; p = 0.280), compared with WWO. Mean ± standard deviation days with self-monitored weight was higher in WWO-E (80.5 ± 5.6; 44.7% of days) than WWO (12.0 ± 1.0; 6.7% of days; p < 0.001) across the 6-month study period. Conclusions: This is the first study to show that provision of a 'smart' scale with weekly tailored feedback substantially increased the frequency of self-weighing and the proportion of participants achieving an initial clinically significant ≥5% weight loss (52% vs. 28%) in an online commercial weight management program. Both WWO and WWO-E produced significant weight loss over 6 months. While mean weight losses were slightly greater in the enhanced group, the difference was not statistically significant in this small sample. This study provides support for the clinical utility of online commercial weight management programs and the potential for supporting technology such as 'smart' scales to improve adherence to body-weight self-monitoring and clinical outcomes.

Migraine and obesity: epidemiology, possible mechanisms and the potential role of weight loss treatment.

Migraine and obesity are two public health problems of enormous scope that are responsible for significant quality of life impairment and financial cost. Recent research suggests that these disorders may be directly related with obesity exacerbating migraine in the form of greater headache frequency and severity, or possibly increasing the risk for having migraine. The relationship between migraine and obesity may be explained through a variety of physiological, psychological and behavioural mechanisms, many of which are affected by weight loss. Given that weight loss might be a viable approach for alleviating migraine in obese individuals, randomized controlled trials are needed to test the effect of weight loss interventions in obese migraineurs. Large-scale weight loss trials have shown that behavioural interventions, in particular, can produce sustained weight losses and related cardiovascular improvements in patients who are diverse in body weight, age and ethnicity. Consequently, these interventions may provide a useful treatment model for showing whether weight loss reduces headache frequency and severity in obese migraineurs, and offering further insight into pathways through which weight loss might exert an effect.

The neurocognitive connection between physical activity and eating behaviour.

As obesity rates increase worldwide, healthcare providers require methods to instill the lifestyle behaviours necessary for sustainable weight loss. Designing effective weight-loss interventions requires an understanding of how these behaviours are elicited, how they relate to each other and whether they are supported by common neurocognitive mechanisms. This may provide valuable insights to optimize existing interventions and develop novel approaches to weight control. Researchers have begun to investigate the neurocognitive underpinnings of eating behaviour and the impact of physical activity on cognition and the brain. This review attempts to bring these somewhat disparate, yet interrelated lines of literature together in order to examine a hypothesis that eating behaviour and physical activity share a common neurocognitive link. The link pertains to executive functions, which rely on brain circuits located in the prefrontal cortex. These advanced cognitive processes are of limited capacity and undergo relentless strain in the current obesogenic environment. The increased demand on these neurocognitive resources as well as their overuse and/or impairment may facilitate impulses to over-eat, contributing to weight gain and obesity. This impulsive eating drive may be counteracted by physical activity due to its enhancement of neurocognitive resources for executive functions and goal-oriented behaviour. By enhancing the resources that facilitate 'top-down' inhibitory control, increased physical activity may help compensate and suppress the hedonic drive to over-eat. Understanding how physical activity and eating behaviours interact on a neurocognitive level may help to maintain a healthy lifestyle in an obesogenic environment.

Improvement of migraine headaches in severely obese patients after bariatric surgery.

OBJECTIVES: Research increasingly suggests that obesity is an exacerbating factor for migraine. However, it is less clear whether weight loss may help to alleviate migraine in obese individuals. We examined whether weight loss after bariatric surgery is associated with improvements in migraine headaches. METHODS: In this prospective observational study, 24 patients who had migraine according to the ID-Migraine screener were assessed before and 6 months after bariatric surgery. At both time points, patients had their weight measured and reported on frequency of headache days, average headache pain severity, and headache-related disability over the past 90 days via the Migraine Disability Assessment questionnaire. Changes in headache measures and the relation of weight loss to these changes were assessed using paired-sample t tests and logistic regression, respectively. RESULTS: Patients were mostly female (88%), middle-aged (mean age 39.3), and severely obese (mean body mass index 46.6) at baseline. Mean (±SD) number of headache days was reduced from 11.1 ± 10.3 preoperatively to 6.7 ± 8.2 postoperatively (p < 0.05), after a mean percent excess weight loss (%EWL) of 49.4%. The odds of experiencing a ≥50% reduction in headache days was related to greater %EWL, independent of surgery type (p < 0.05). Reductions in severity were also observed (p < 0.05) and the number of patients reporting moderate to severe disability decreased from 12 (50.0%) before surgery to 3 (12.5%) after surgery (p < 0.01). CONCLUSIONS: Severely obese migraineurs experience marked alleviation of headaches after significant weight reduction via bariatric surgery. Future studies are needed to determine whether more modest, behaviorally produced weight losses can effect similar migraine improvements.