You are reading Polycystic ovary syndrome: is there a link with insulin resistance?

Endocrinology

Polycystic ovary syndrome: is there a link with insulin resistance?

September 26, 2018

The polycystic ovary (PCO) affects 5 to 10% of women of childbearing age. This condition, defined by the combination of ovarian dysfunction and hyperandrogenism (excessive production of androgens) involves a series of alterations both at the level of the reproductive apparatus (ovulation failure, menstrual irregularities, morphology of the polycystic ovary) and in the metabolic area. In fact, in addition to compromising fertility, this condition increases the risk of overweight and obesity and involves significant changes in the metabolism of fats and sugars. Insulin resistance is a pathological condition in which the body’s tissues progressively lose their ability to respond to the signal of the hormone produced by the pancreas, essential to let glucose from the blood to the cells that use it to produce energy, seems to have a direct correlation with this disease. We discuss this topic with Dr. Nazarena Betella from the department of Endocrinology and Medical Andrology.

 

Diagnosis of the polycystic ovary

Although there is no single definition, the diagnostic criteria used by the main Scientific Societies require the coexistence of at least two of the following characteristics: 1) the detection of high levels of androgens in the blood and/or clinical manifestations attributable to a state of hyperandrogenemia (for example, hirsutism, or the abnormal and excessive presence of hair with male distribution in a female subject), 2) ovulatory dysfunction with irregular menstrual cycles (the most common manifestation is ‘oligoamenorrhea’, i.e. the reduced frequency or complete absence of menstrual cycles in conditions of chronic anovulation) and 3) ultrasound findings of ovarian polycystosis (presence of more than 10 cysts with a diameter of 2-8 mm each).

 

Although it represents the most common endocrine metabolic disorder in women of reproductive age, the diagnosis of PCO is made only after excluding other more specific clinical conditions (for example, hyperprolactinemia and congenital adrenal hyperplasia).

 

Since it is a typical endocrinological disease, for years it has been treated with the administration of female hormones (estroprogestinic or only progesterone) and antiandrogens. However, contraceptives, even those that contain low levels of estrogen, are not only not effective against metabolic changes of the disease, but can worsen the lipid profile, with an increase in triglycerides in particular.

 

There is increasing evidence to support the hypothesis that polycystic ovary syndrome (PCOS) may be a complex multigenic disorder with strong environmental influences, among which diet and lifestyle seem to play a major role. Therefore, the therapeutic strategy should not only be oriented to the resolution of disorders related to hyperandrogenemia and ovarian dysfunction, but also to the improvement of metabolic alterations, promoting the establishment of a virtuous circle.

Related articles

Metabolic alterations related to this disease

It is now clear that metabolic changes are a central component of polycystic ovary syndrome: more than 60% of women affected by the syndrome have insulin resistance (and you get to 100% in obese patients). Insulin resistance is the antechamber to diabetes, metabolic syndrome and cardiovascular diseases. Where does insulin resistance come from? From sedentariness, from an unbalanced diet and from stress. The combination of these factors causes overproduction of free radicals and inflammation, closely linked to insulin resistance, but it is also the cause of anxiety and depression, a condition widely found among these women.

 

In January 2013, a study published in Nature Review Neuroscience showed that the regulation of insulin and glucose metabolism is not a local phenomenon that affects only the intestine, pancreas and liver, but a complex systemic phenomenon in which the central nervous system (especially the hypothalamus) and the vegetative system play a fundamental role. This is why today, in the treatment of the polycystic ovary, we aim at an integrated approach based on physical activity, nutrition, anti-stress and meditative techniques, acupuncture.

 

Polycystic ovary and infertility

The presence of polycystic ovaries is one of the most common causes of female infertility and spontaneous abortions in the first trimester of pregnancy. Among the metabolic causes involved in the genesis of this syndrome, insulin resistance plays a key role. It involves an increased production of androgens by the ovary’s theca, which cause a dysregulation of the pulsatility of LH (key hormone of ovulation), while at the same time the endometrium undergoes an abnormal growth (with consequent problems in embryo implantation). The treatment of insulin resistance allows a resolution of PCO in a high percentage of cases, with a consequent reduction of menstrual disorders, increased fertility and lower risk of early miscarriages.

 

The importance of nutrition

One of the strategies for solving insulin resistance is to follow a low glycemic index (GI) diet. The GI represents the speed at which a food containing 50 grams of carbohydrates raises blood sugar (i.e. the concentration of glucose in the blood), expressed in percentage terms in relation to a reference food, i.e. glucose or white bread with a glycemic index of 100. The GI is considered low if less than 55, medium if between 56 and 69, high if greater than 70. After the intake of carbohydrates with a high GI, glycaemia undergoes a sharp rise, a lot of insulin is secreted with consequent hyperstimulation of the tissues.

 

Several factors influence the GI of a food: the liquid or solid form, the quantity of fiber (the GI is inversely proportional to the fiber content, therefore fruit and vegetables, legumes, whole grains and a paste seasoned with vegetables have a lower GI than refined grains or a paste seasoned with an elaborate sauce), the percentage of other macromolecules (the GI is reduced as the proportion of fat and protein increases at the expense of the carbohydrate component), the method of preparation (a raw food has a lower GI than the cooked one itself, because with cooking the bonds between the food molecules are broken, which become more rapidly assimilable), the cooking times (for the same reason, pasta cooked al dente is absorbed more slowly) and the degree of chewing of the food.

 

High GI foods include: refined cereals (rice, white bread), desserts (ice cream, wafers, biscuits, croissants, cakes), sugary carbonated drinks, foods that contain high percentages of simple sugars among their ingredients, such as sucrose, dextrose, glucose syrup.

 

Other foods to be considered for their medium-high GI are potatoes and certain fruits and vegetables (carrots, melon, pumpkin, raisins).

 

Ultimately, each meal, in order to be complete, must also contain fat and protein and should not provide more than 55% of the daily carbohydrate requirement.

You may also like

Do not miss our advice for your health

Sign up for the weekly Humanitas Health newsletter and get updates on prevention, nutrition, lifestyle and tips to improve your lifestyle