Tai chi for overweight/obese adolescent and young women with polycystic ovary syndrome: study protocol for a randomized controlled trial

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder and affects 5–20% of reproductive-age women [1]. It is a complex syndrome characterized by reproductive and metabolic implications including amenorrhea /oligomenorrhea, hyperandrogenism (including hirsutism) or acne and very often by overweight and obesity [2, 3].

Overweight or obesity in adults has been defined by the World Health Organization (WHO) (Body Mass Index (BMI) ≥ 25 kg/m² for overweight, BMI ≥ 30 kg/m² for obesity). In studies on Asian subjects, overweight is considered to be a BMI ≥ 23 kg/m²and obesity a BMI ≥ 25 kg/m² [4]. For adolescents, age- and gender-specific percentile distributions for BMI using the Centers for Disease Control and Prevention growth charts were used to identify those who were overweight (85th–95th percentile) or obese (> 95th percentile) [5].

The prevalence of overweight and obesity in women with PCOS is highly variable since it differs in the general population according to age, ethnicity and geographic regions. A meta-analysis reported that the prevalence of obesity (BMI ≥ 30 kg/m²) in women with PCOS ranged from 12.5 to 100% with a pooled estimated prevalence of 49% (95% CI 42–55%); the prevalence of overweight (BMI ≥ 25 kg/m²) and obesity (BMI ≥ 30 kg/m²) ranged from 6 to 100% with a pooled estimated prevalence of 61% (95% CI 54–68%). Also, the prevalence of central obesity was significantly higher in women with PCOS compared with controls [6].

Despite the highly variable reported prevalence of overweight and obesity in women with PCOS, it is confirmed that being obese is significantly associated with worse metabolic and reproductive outcomes measured, except for hirsutism, when compared to normal-weight women with PCOS [6]; whereas women who were overweight but not obese only had no differences in total testosterone (T), hirsutism, total cholesterol and low-density lipoprotein cholesterol (LDL-C) compared to normal-weight women, and no differences in sex-hormone-binding globulin (SHBG), total T and fasting lipids compared to obese women [6]. Central obesity was associated with higher fasting insulin [6]. Also, overweight and obesity is associated with unfavorable in vitro fertilization (IVF)/ intracytoplasmic sperm injection (ICSI) outcomes in PCOS patients treated with a gonadotropin-releasing hormone (GnRH) agonist using the long protocol [7, 8].

Therefore, it is of great importance to be aware that overweight and obese PCOS patients, especially adolescent and young women with PCOS, should also be advised to lose weight. This will not only assist with their immediate symptoms but also will help to prevent the development of diabetes and cardiovascular disease in later life. Lean women with PCOS should be cautioned of the high risk of overweight, obesity and central obesity associated with PCOS, and be encouraged to engage in health behaviors that prevent weight gain.

It is confirmed that even modest weight loss of just 5% body weight in obese women with PCOS can restore regular menstruation and improve response to ovulation induction and fertility treatment [9]. Lifestyle modification, use of metformin, taking hormonal contraceptives (HCs), and bariatric surgery are the main treatment options in obese patients with PCOS recommend by guidelines [10]. Lifestyle modification is the first-line management which could both prevent weight gain and induce weight loss. However, improved engagement and sustainability remain challenges while using. Medications such as metformin, HCs and bariatric surgery have been used with the need for large-scale randomized clinical trials to define their roles and side effects. Novel therapies including inositols [11] and statins [12] have been under investigation lately. Complementary and alternative medicine approaches such as Chinese medicine formulas [13] and acupuncture [14] are also under study. Their efficacy and safety still need to be addressed. More research is needed to assign better therapeutic regimens in overweight and obese PCOS patients and strategies to prevent the development of comorbidities.

Tai Chi is an exercise system followed Chinese Medicine theory which dates back to seventeenth century. It can maintain the harmony between qi and the blood, keep yin and yang in balance and has traditionally been used in various forms for the promotion and maintenance of health and longevity in China [15]. Recently, physiological and psychosocial benefits of Tai Chi on chronic diseases which are very closely related to PCOS, such as obesity, cardiovascular diseases (CVD) and type-2 diabetes [16‐18], have been addressed.

A recently published randomized controlled trial of 374 Chinese adults reported that, a 12-week Tai Chi training led to significant loss of 0.50 of body weight and 0.47 of fat mass compared with a control group, which is a similar effect as in a walking group [19]. Another randomized clinical trial consisting of 266 Chinese adults with hypertension reported that a 12-month Tai Chi training could significantly lower BMI compared with a control group (22.25 ± 2.91 vs 23.16 ± 2.94, p < 0.001) [16].

To the best of our knowledge, there is no study so far investigating the effect of Tai Chi in women with PCOS. Therefore, the purpose of the present study is to evaluate the effect of Tai Chi in PCOS and the feasibility of executing a large-scale clinical trial.

To the best of our knowledge, this is the first study to determine the effectiveness and feasibility of Tai Chi in treating PCOS. The result of the present study should provide evidence to assess the feasibility of a larger multicenter, randomized controlled trial in the future. One limitation is that the present study design did not include an assessment of the physiological benefits of Tai Chi. The Polycystic Ovary Syndrome Health-Related Quality of Life Questionnaire (PCOSQ) or other questionnaires will be employed in further study [23].