Living with polycystic ovarian syndrome (PCOS) often involves a combination of lifestyle changes and medication. However, the condition can become more complex to manage alongside certain factors, including having overlapping conditions such as hypothyroidism as well as being severely overweight or obese.
PCOS and obesity are often comorbid. Research does not show that obesity causes PCOS; however, it can exacerbate many aspects of the condition, particularly cardiovascular risk factors such as dyslipidemia and glucose intolerance.
What Are the Risks for an Obese Patient with PCOS?
Obesity has been linked to dysfunction in the hypothalamic-pituitary-ovarian axis through multiple mechanisms. Obesity can further complicate PCOS, as it is associated with both insulin resistance and compensatory hyperinsulinemia. Insulin is known to stimulate androgen production by the ovaries. Research published in Seminars in Reproductive Medicine reports increased inflammatory and growth factors among obese patients, which may further stimulate the ovaries to produce excess androgens or inhibit the aromatization of androgens to estrogen.
Insulin resistance and hyperinsulinemia contribute to disordered gonadotropin secretion by the hypothalamus. Adipokines such as leptin, which signals to the hypothalamus, are also crucial to controlling ovulatory function. Obesity may also influence sex steroids by affecting their peripheral metabolism or regulators. Androgen metabolism can have both local and systemic effects related to PCOS symptoms.
Insulin resistance and a relatively androgenic state are also associated with the suppression of secretion of sex hormone-binding globulin by the liver. In turn, this leads to greater bioavailability of androgens in the body, including in the brain. The aromatization hypothesis postulates that the blood-brain barrier is not permeable to estrogens — only androgens, which are then aromatized in the central nervous system cells.
Obesity is associated with an increased chance of metabolic symptoms of PCOS. It can also cause an increase in the prevalence of dyslipidemia as well as a greater chance of developing the cluster of conditions known as metabolic syndrome.
For patients with PCOS who wish to conceive, obesity is a clear baseline predictor of response to fertility treatment. Increasing BMI within PCOS is associated with failure to respond to gonadotropins and weaker IVF results.
How Can Ultrasound Help Mitigate the Risks of Obesity in the Context of PCOS?
Ultrasound plays a role in diagnosing PCOS, which is still a diagnosis of exclusion. Other etiologies that may also present with polycystic ovaries, hyperandrogenism and chronic anovulation — therefore, physicians must rule out other potential options such as frank ovarian failure, states of steroid deficiency without androgen excess or failure, or dysfunction of the hypothalamic-pituitary axis.
Typically, transvaginal ultrasound is performed on the second or third day of the menstrual cycle. Doppler is used to assess ovarian stromal vascularity, and spectral Doppler is used for quantitative assessment of the flows by measuring intraovarian resistance index and peak systolic velocity. Stromal volume, antral follicle count, stromal echogenicity and polycystic ovary morphology can also aid diagnosis.
2D ultrasound showing PCOS
According to research published in the Journal of Evidence-Based Medicine, assessment of polycystic ovary and anovulation may be best done using 3D ultrasound combined with color and Power Doppler. These tools allow for a more accurate assessment of ovarian volume, ovarian morphology and stromal volume.
The presence of intra-abdominal fat makes it harder for ultrasound waves to penetrate through the organs, which is necessary to obtain a quality image. Ultrasound manufacturers are working to increase the depth of penetration to ensure there is enough spatial resolution to yield a quality image for patients who carry more of this fat. Non-focal imaging offers automatic adjustment of the focus position, allowing ultrasound technicians to achieve greater abdominal penetration with higher frame rates as well as a high focus rate.
Exploring Lifestyle Changes With Patients
Lifestyle changes such as diet changes and physical activity can mitigate obesity, but patients with PCOS face many obstacles to adopting effective lifestyle therapy. In a survey of physicians published in Nutrients, participants who regularly treated PCOS reported that guaranteeing patients' access to other providers, such as dieticians, was a significant challenge. Another common obstacle was time: Outlining an effective diet and exercise plan that patients felt confident adhering to was difficult in the brief window they had to consult each patient, physicians said.
These challenges do not mean that OB/GYNs should give up on lifestyle therapies. Encouraging a patient to avoid dangerous weight loss options such as fad diets and instead follow strong nutritional choices such as whole grains and lean protein can help them manage insulin resistance. Overall, lifestyle changes show modest benefits in terms of improvement of body composition, insulin sensitivity and hyperandrogenism.
However, there is not compelling evidence that lifestyle changes will improve glucose tolerance, dyslipidemia or clinical reproductive outcomes.
The Future of PCOS Obesity Treatment
Pharmaceutical interventions, including insulin-sensitizing agents such as metformin or troglitazone, provide another possible avenue of treatment for patients with PCOS and obesity. As research published in Annals of Translational Medicine reports: "Anecdotal observation suggest[s] that metformin could also be helpful to improve hyperandrogenic symptoms in some cases and might also promote weight loss." However, clomiphene has largely replaced it as a treatment for anovulatory PCOS. Other insulin sensitizers only have limited studies in patients with PCOS to support their use.
Several antiobesity drugs are available on the market, but orlistat is the only one commonly suitable for women with PCOS and obesity. This drug inhibits intestinal lipase activity and fat absorption. However, there are limited studies on orlistat in women with PCOS. The same Seminars in Reproductive Medicine study reports that the drug's adverse effects for this group include steatorrhea, flatulence and, in rare cases, hepatoxicity.
In recent years, bariatric surgery has become a more popular option to treat morbid obesity with PCOS. This therapy may help patients reach large-scale weight loss and maintain it over time. Several case studies on the surgery report weight loss, improved fertility and the resolution of biochemical abnormalities associated with PCOS, notes a review published in Cureus. However, larger and more rigorous studies are needed.
Obesity and PCOS are clearly linked, but one does not cause the other. However, obesity can aggravate the PCOS phenotype, particularly when it comes to cardiovascular risk factors. Treatment options focusing on weight loss remain the best interventions for patients with both conditions.
