Polycystic ovarian syndrome (PCOS) is associated with metabolic symptoms such as hyperinsulinemia. Time-restricted eating may reduce serum insulin and improve insulin resistance in patients with PCOS. Currently, there are few studies investigating time-restricted eating in patients with PCOS. The investigators plan to test the feasibility of time-restricted eating in the management of PCOS by means of a real-world clinical intervention. The investigators will determine if an 18:6 eating protocol reduces insulin levels by means of a randomised controlled crossover trial.
Background: Polycystic ovarian syndrome (PCOS) is the most common reproductive endocrinopathy in women of reproductive age with many associated metabolic symptoms, in particular hyperinsulinemia, insulin resistance and a high lifetime risk of type 2 diabetes mellitus. The effects of time-restricted eating on metabolic profiles have been investigated in many endocrinopathies, but there are minimal data in PCOS. Methods: This study will investigate the feasibility of time-restricted eating in the management of PCOS, and its effects on insulin levels and other metabolic parameters. To achieve this, the investigators will recruit 20 patients with PCOS (normal weight, overweight, obese). In a randomised cross-over design, participants will be observed for two consecutive 12 week periods (with a 4 weeks washout period in between) following either 'time-restricted eating' or 'usual eating', detailed below. 1. 18:6 protocol: 18 hours of fasting and a 6-hours eating window, with no other specific dietary advice. Participants choose their own 6-hour period according to their lifestyle and preference. 2. Usual eating: follow usual eating patterns, no time restriction, no other dietary advice When fasting, participants are permitted to consume plain water, unflavoured/unsweetened sparkling water, black breakfast tea and black coffee. Dietary intake will be determined at baseline, at midpoint of each study arm, and at the end of the study using Nutritics software. Participants will self-record dietary intake using the Nutritics 'app'. The primary endpoints will be serum insulin and feasibility of the intervention as well as safety, acceptability, and compliance with time-restricted eating. Secondary endpoints will be insulin resistance (Homeostatic Model Assessment for Insulin Resistance (HOMA-IR)), androgens (testosterone, free testosterone, dehydroepiandrosterone sulfate (DHEA-S), androstenedione, 17-Hydroxyprogesterone (17-OHP) and sex hormone binding globulin (SHBG)), appetite (10-point visual analogue scale), hunger/satiety (glucagon-like peptide 1 (GLP-1), grehlin, PYY and oxyntomodulin, fasting glucose, HbA1c, lipid profile, lipoprotein lipid A, apolipoprotein A1, apolipoprotein B, anthropometrics (weight, body mass index, hip and waist circumference), dietary intake (calorie and macronutrient intake; micronutrient intake including iron, calcium; dietary pattern including timing). Results: Safety and acceptability will be measured by adverse event reporting and measurement of adherence. Paired t-test will be used to assess between baseline and post intervention measurements. Results considered statistically significant if p\<0.05. Discussion: Time-restricted eating has potential to aid in improvement of insulin resistance in patients with PCOS based on studies in other populations. There is no substantial literature on this subject to date in the PCOS patient cohort, with this being the first randomised study to date. The investigators will discuss the effects of time-restricted eating on insulin levels in the specific population of women with PCOS based on the results.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
SINGLE
Enrollment
20
Following a 3 day baseline dietary assessment using the Nutritics 'app', patients will immediately commence time-restricted eating on a 18:6 basis (18 hours fasting, 6 hours eating window) for 12 weeks. Participants will consume all their meals within a daily 6-hour period of their choosing, and this may change according to patient's lifestyle and preference to reflect a real-world situation. Participants may eat ad libitum / according to appetite during the eating period. Participants will fast for 18 hours per day, consuming only plain water, unflavoured/unsweetened sparkling water, black breakfast tea or black coffee. Alcohol must not be consumed during fasting periods Dietary intake will again be measured using the Nutritics 'app' midpoint through the 12-week period (week 6 +/- 1 week) and in the last week of the intervention (week 11/12).
Following a 3-day baseline dietary assessment using the Nutritics 'app', participants with be directed to continue with their usual dietary intake without any time-related restrictions for 12 weeks. There will be no defined eating window and fasting or restrictions regarding types of food or drink consumed. Dietary intake will again be measured using the Nutritics 'app' midpoint through the 12-week period (week 6 +/- 1 week) and in the last week of the intervention (week 11/12).
Robert Graves Institute of Endocrinology, Tallaght University Hospital
Dublin, Leinster, Ireland
RECRUITINGDrop-out rate
Assessing intervention feasibility
Time frame: 6 weeks
Drop-out rate
Assessing intervention feasibility
Time frame: 12 weeks
Adverse outcomes as assessed by CTCAE v4.0
Assessing intervention feasibility
Time frame: 6 weeks
Adverse outcomes as assessed by CTCAE v4.0
Assessing intervention feasibility
Time frame: 12 weeks
Change in serum insulin
Measured with serum insulin levels to assess effects
Time frame: 6 weeks
Change in serum insulin
Measured with serum insulin levels to assess effects
Time frame: 12 weeks
Change in food diaries
Assessment of change of eating behaviours
Time frame: 6 weeks
Change in food diaries
Assessment of change of eating behaviours
Time frame: 12 weeks
Change in insulin resistance
Assessed by Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and other ratio calculations measuring insulin resistance
Time frame: 6 weeks
Change in insulin resistance
Assessed by Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and other ratio calculations measuring insulin resistance
Time frame: 12 weeks
Change in testosterone levels
Assessed by plasma testosterone
Time frame: 6 weeks
Change in testosterone levels
Assessed by plasma testosterone
Time frame: 12 weeks
Change in free testosterone levels
Assessed by plasma free testosterone
Time frame: 6 weeks
Change in free testosterone levels
Assessed by plasma free testosterone
Time frame: 12 weeks
Change in dehydroepiandrosterone sulfate (DHEA-S) levels
Assessed by plasma dehydroepiandrosterone sulfate (DHEA-S)
Time frame: 6 weeks
Change in dehydroepiandrosterone sulfate (DHEA-S) levels
Assessed by plasma dehydroepiandrosterone sulfate (DHEA-S)
Time frame: 12 weeks
Change in androstenedione levels
Assessed by plasma androstenedione
Time frame: 6 weeks
Change in androstenedione levels
Assessed by plasma androstenedione
Time frame: 12 weeks
Change in sex hormone binding globulin (SHBG) levels
Assessed by plasma sex hormone binding globulin (SHBG)
Time frame: 6 weeks
Change in sex hormone binding globulin (SHBG) levels
Assessed by plasma sex hormone binding globulin (SHBG))
Time frame: 12 weeks
Change in 17-Hydroxyprogesterone (17-OHP) levels
Assessed by 17-Hydroxyprogesterone (17-OHP)
Time frame: 6 weeks
Change in 17-Hydroxyprogesterone (17-OHP) levels
Assessed by 17-Hydroxyprogesterone (17-OHP)
Time frame: 12 weeks
Change in appetite
Measured by a validated 10-point visual analogue scale on a scale of 1-10, 1 being not hungry at all and 10 being very hungry
Time frame: 6 weeks
Change in appetite
Measured by a validated 10-point visual analogue scale on a scale of 1-10, 1 being not hungry at all and 10 being very hungry
Time frame: 12 weeks
Change in markers of satiety
Assess by plasma GLP-1
Time frame: 6 weeks
Change in markers of satiety
Assess by plasma GLP-1
Time frame: 12 weeks
Change in markers of satiety
Assess by plasma PYY
Time frame: 6 weeks
Change in markers of satiety
Assess by plasma PYY
Time frame: 12 weeks
Change in markers of satiety
Assess by plasma oxyntomodulin
Time frame: 6 weeks
Change in markers of satiety
Assess by plasma oxyntomodulin
Time frame: 12 weeks
Change in markers of hunger
Assess by plasma ghrelin
Time frame: 6 weeks
Change in markers of hunger
Assess by plasma ghrelin
Time frame: 12 weeks
Change in fasting glucose
Assessed in serum glucose measurements
Time frame: 6 weeks
Change in fasting glucose
Assessed in serum glucose measurements
Time frame: 12 weeks
Change in HbA1c
Assessed in serum HbA1c measurements
Time frame: 6 weeks
Change in HbA1c
Assessed in serum HbA1c measurements
Time frame: 12 weeks
Change in lipids
Assessed by Lipid profile
Time frame: 6 weeks
Change in lipids
Assessed by Lipid profile
Time frame: 12 weeks
Change in lipids
Assessed by Lipoprotein lipid A levels
Time frame: 6 weeks
Change in lipids
Assessed by Lipoprotein lipid A levels
Time frame: 12 weeks
Change in lipids
Assessed by Apolipoprotein A1 levels
Time frame: 6 weeks
Change in lipids
Assessed by Apolipoprotein A1 levels
Time frame: 12 weeks
Change in lipids
Assessed by Apolipoprotein B levels
Time frame: 6 weeks
Change in lipids
Assessed by Apolipoprotein B levels
Time frame: 12 weeks
Change in body weight
Body weight (kg)
Time frame: 6 weeks
Change in body weight
Body weight (kg)
Time frame: 12 weeks
Change in body mass index
BMI (kg/m2)
Time frame: 6 weeks
Change in body mass index
BMI (kg/m2)
Time frame: 12 weeks
Change in anthropometric measurements (waist circumference)
Waist circumference (cm)
Time frame: 6 weeks
Change in anthropometric measurements (waist circumference)
Waist circumference (cm)
Time frame: 12 weeks
Change in anthropometric measurements (waist-hip ratio)
Waist-hip ratio
Time frame: 6 weeks
Change in anthropometric measurements (waist-hip ratio)
Waist-hip ratio
Time frame: 12 weeks
Change in dietary intake
Assessed using interval dietary assessments with Nutritics 'app'
Time frame: 6 weeks
Change in dietary intake
Assessed using interval dietary assessments with Nutritics 'app'
Time frame: 12 weeks
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.