Low validity of predictive equations for calculating resting energy expenditure in overweight and obese women with polycystic ovary syndrome

Exploring the physiological factors relating to energy balance in women with polycystic ovary syndrome: a scoping review

Polycystic ovary syndrome (PCOS) occurs in 8%-13% of reproductive-aged women and is associated with reproductive, metabolic, and psychological dysfunction. Overweight and obesity are prevalent and exacerbate the features of PCOS. The aim of this review is to evaluate the extent of evidence examining the physiological factors affecting energy homeostasis, which may impact weight gain, weight loss, and weight maintenance in PCOS, and identify research gaps and recommendations for future research. Literature searches using MEDLINE, EMBASE, PsycInfo, AMED, CINAHL, and Cochrane Central Register of Controlled Trials were conducted up to June 22, 2022. Abstracts, non-English-language articles, and reviews were excluded. A total of n = 78 (n = 55 energy intake and n = 23 energy expenditure) primary research papers were included. Papers with multiple outcomes of interest were counted as separate studies. Energy-intake studies (n = 89) focussed on assessing food, nutrient, or supplements stimuli and were grouped into the outcomes of gastrointestinal appetite hormones (n = 43), adipokines (n = 34), subjective appetite (n = 9), functional brain imaging (n = 3), and neuropeptides (n = 0). Energy-expenditure studies (n = 29) were grouped into total energy expenditure (n = 1), resting energy expenditure (n = 15), meal-induced thermogenesis (n = 3), nutrient oxidation (n = 5), and metabolic flexibility (n = 5). Across both energy-intake and -expenditure papers, 60% of the studies compared outcome responses in women with PCOS with a control group. Results were inconsistent, with 57% reporting no differences and 43% reporting altered responses in PCOS compared with controls, including blunted appetite hormone responses, metabolic inflexibility, and reduced energy expenditure. The authors identified that there is inconsistent, yet preliminary, evidence of possible altered physiological factors, which may impact energy balance and weight management. Further work is needed to act on the identified clinical and research gaps to support women with PCOS and health professionals in informing and achieving realistic weight-management goals for women with PCOS.

SYSTEMATIC REVIEW REGISTRATION

The protocol was prospectively registered on the Open Science Framework on February 16, 2021 (https://osf.io/9jnsm).

Resting Energy Expenditure in Patients with Extreme Obesity: Comparison of the Harris-Benedict Equation with Indirect Calorimetry

Background: The main objective of the work was the analysis and description of data on body composition and resting energy expenditure (REE) values of selected groups of patients with obesity whose REE measurement results using indirect calorimetry reached a level below 95% of the predicted REE calculated using the Harris-Benedict (H-B) equation. The sub-goals were to describe the dependence of body composition on the size of the REE and to find out if the deviations between the number of the total measured REE and the REE calculated using H-B in the adapted group (patients with altered REE values, lower than expected caused by long caloric restriction) are significant. Methods: For the research, 71 (39 women and 32 men) patients treated in obesitology were selected. Patients underwent the measurement of resting metabolism using indirect calorimetry (IC) and body composition measurement on the bioimpedance device and, at the same time, the value of resting metabolism was calculated for everyone using the H-B equation. The whole group was divided into five groups according to the deviation of the measurement using IC and the calculation of the H-B equation. Results: In the total set of examined individuals, there were 32.4% with a reduced REE value compared to the REE calculation according to the H-B equation, which corresponds to 23 individuals. In the adapted group, the average measured REE was 2242 ± 616 kcal compared to the H-B calculation of 2638 ± 713 kcal. Statistically, these results were not significant, but a high case-to-case variation was found. The highest deviation from the H-B predictive calculation was -42% and +43% in the whole research group. The amount of muscle tissue in the adapted group averaged 44.3 ± 11.9 kg and the amount of fat-free mass (FFM) 77.9 ± 20.1 kg. When statistically testing the dependence of REE on FFM and muscle tissue in the adapted group, a strong correlation was found. Conclusions: The H-B equation alone is not suitable for setting a suitable diet therapy for an individual with obesity. In order to select and characterize a group of adapted individuals, it will be necessary to use other methods or a larger research sample, and preferably examine and divide patients with specific comorbidities or include their health status.

Mindfulness-based program to support lifestyle modification and weight loss in infertile women: randomized controlled trial

OBJECTIVE

We evaluated the short-term effects of a mindfulness-based program (MBP) on weight loss through lifestyle modification in infertile women who were overweight or obese.

METHODS

The participants were randomly assigned to 8 consecutive weekly sessions of MBP plus diet or diet alone. Both groups received a customized dietary plan. Body measures were taken and a questionnaire was applied to evaluate dietary habits at baseline and three months later.

RESULTS

The study was completed by 28 women in the MBP group and 24 in the control group. Body weight decreased 1.8 kg (2.1%) in the MBP group (p = 0.001, follow-up vs. baseline) and 1.7 kg (1.9%) in the control group (p = 0.035). There was an average reduction of 2.9 cm of waist circumference in the MBP group (p = 0.008) and 0.3 cm in the control group (p = 0.633). There was a significant reduction in the daily energy intake of the women attending the MBP (mean difference -430 Kcal/day, p=0.010) whereas no significant change was observed in the control group.

CONCLUSION

In the short term, this MBP did not affect weight loss in infertile women, but the MBP intervention contributed to reduce waist circumference, possibly due to a significant decrease in food energy intake.

TRIAL REGISTRATION NUMBER

RBR-7by76r.