A sedentary lifestyle has been linked to a doubled risk of uterine myoma

The habit of spending time in a sedentary position - both at work and at leisure - is fraught with many adverse health consequences, including obesity, estrogen metabolism and chronic inflammation. These, in turn, are linked to the development of uterine myoma. How much the risk of its occurrence increases if a woman sits at least two hours a day on weekends or in the evening after work, Chinese scientists have found out.

Sedentary lifestyle - a real scourge of the XXI century. For example, according to some calculations, in three EU countries more than half of the people work sitting down: in the Netherlands - 55%, in Germany - 54%, in Luxembourg - 52%. Back in 2016, scientists stated that approximately 3.8% of all deaths in the world are due to sitting for more than three hours every day.

Now researchers from Kunming Medical University, Yunnan Center for Disease Control and Prevention, Wuhan Mental Health Center and Baoshan College of Traditional Chinese Medicine in the PRC have found that a sedentary lifestyle - even outside of work, which also doesn't always involve movement - is associated with an increased risk of uterine myoma. It is the most common benign tumor that develops from smooth muscle cells in the cervix or body of the uterus in women of childbearing age (most commonly in their 40s and 50s). Uterine myoma may not cause symptoms, but some patients experience bleeding, pelvic and abdominal pain, infertility and other adverse effects.

The scientists, whose paper is published in the journal BMJ Open, analyzed data from a prospective cohort study of residents of Yunnan Province. The final sample included 6,623 women aged 30-55 years who had not yet experienced menopause and were not pregnant. Participants completed questionnaires and provided information on menstrual history, contraceptive use, education level, occupation, presence of children, lifestyle, physical activity, and diet. After the survey, they underwent physical examination (height and weight measurements) and gynecologic ultrasound.

The analysis showed that most of the participants - 60.8% - spent 2-3.99 hours a day in a sitting position. And it was not about work: such leisure activities as playing chess, using cell phones, tablets, watching TV, reading books or newspapers, knitting were taken into account.

562 women in the entire sample had uterine myoma. Regarding demographic characteristics, the prevalence of this pathology depended on age: uterine myoma was most common in the group over 50 years old, followed by 40-49 years old and 30-39 year olds. Univariate logistic regression also showed that BMI, number of children born safely, menstrual status, and sedentary lifestyle were correlated with uterine myoma.

"Compared with women who spent less than two hours of leisure time sitting each day, participants who sat for 2-3.99 hours, 4-5.99 hours, and more than six hours a day had odds ratios of 1.013, 1.215, and 1.936, respectively. Adjusted analysis showed that leisure sitting was positively correlated with uterine myoma risk: its risk was 2.008 times higher in women who sat more than six hours a day than in women who sat less than two hours a day in their leisure time," the researchers said.

They emphasized that only participants who were premenopausal or had a body mass index greater than 24 were more likely to develop uterine myoma.

Although the cause-and-effect relationship scientists have not been able to establish, they proposed to explain this, among other things, a lack of vitamin D: its deficiency, as shown by previous scientific work, is a risk factor for uterine myoma, and sedentary lifestyle just leads to a decrease in the level of this vitamin in the body. In addition, the habit of spending time in a sedentary position can exacerbate metabolic disorders before menopause and increase the likelihood of benign tumors in the uterine muscular layer.