Childhood Weight May Predispose Girls to PMS After Adolescence

A higher body mass index (BMI) in childhood could mean worse premenstrual syndrome (PMS) for girls later on, a new prospective cohort study indicated.

In a study of 6,524 girls, each additional unit of BMI z-score in childhood (ages 9 to 16) was linked with a 9% higher relative risk of developing premenstrual disorders (PMDs) by young adulthood (ages 18 to 31) in an adjusted model (relative risk 1.09 per unit of z score, 95% CI 1.03-1.15), reported Donghao Lu, MD, PhD, of Karolinska Institutet in Stockholm, Sweden, and colleagues.

Around an average age of 12.7, girls with a higher BMI also saw a higher burden of premenstrual symptoms (β 0.06, 95% CI 0.04-0.08), the researchers wrote in JAMA Network Open.

On top of that, girls who maintained a higher BMI all throughout their adolescence had a significantly higher burden of premenstrual symptoms in young adulthood versus girls who maintained a normal BMI throughout adolescence (β 0.17, 95% CI 0.08-0.27).

Of note, girls who started with a high BMI in childhood but underwent a mild decrease later on in adolescence protected themselves from this higher risk of premenstrual symptoms.

While obesity (more than two standard deviations higher for BMI) was also linked with a higher burden of premenstrual symptoms compared with girls who fell into the normal BMI for age (β 0.27, 95% CI 0.09-0.44), the overweight or obesity categories weren’t significantly linked with a higher risk for an official diagnosis for a case of PMD.

“If this association is confirmed in independent populations, maintaining a normal body mass in childhood may be considered for preventing the development of a range of future health hazards in young adults, including PMDs,” Lu’s group suggested.

The study is a “valuable contribution,” according to the author of an accompanying commentary, Chighaf Bakour, MD, PhD, of the University of South Florida in Tampa. She said the study “offers evidence in support of the hypothesis that childhood and adolescent BMI is a risk factor for PMS symptoms and possibly the occurrence of PMDs by young adulthood.”

While Bakour emphasized that the association is not causal, she suggested that future studies should start following girls in early childhood and assess to what extent sustained weight loss can ease the burden of PMDs in adulthood.

Lu’s group drew upon data from the Growing Up Today Study. Height and weight were self-reported by participants during follow-up questionnaires throughout the years. BMI z score was based on the sex-specific smoothed percentile curves for BMI for age from the 2000 Centers for Disease Control and Prevention Growth Charts.

The cohort was 93.6% white and 15.4% met the criteria for PMD. All models were adjusted for age at BMI assessment, cohort membership, race, moderate/vigorous physical activity, paternal educational level, maternal marital status, and use of multivitamins.

Premenstrual symptoms were assessed on a four-point Likert-like scale using a modified version of the Calendar of Premenstrual Experiences. The female participants rated experiences of eight affective and 19 physical or behavioral symptoms in “most months of the year for at least several days before their period begins, which was scored from 1 to 4 (severe),” the team explained.

Premenstrual disorders were then classified into either premenstrual symptoms or probable premenstrual dysphoric disorder, which was classified based upon the DSM-5 criteria as having the following symptoms from three categories:

• One or more of four severe affective symptoms, including irritability or anger, mood swings or tearfulness, depression, and anxiety

• Five or more of 11 symptoms, including the four above and hypersensitivity, desire for aloneness, insomnia, difficulty concentrating, fatigue, food cravings, and/or other physical symptoms

• Moderate or severe effect on life activities or relationships

A limitation of the study, Bakour said, was a lack of adjustment for child abuse — either physical, sexual, or emotional — which can impact both obesity and PMDs.

“Other adverse childhood experiences, including neglect and household dysfunction (such as mental illness, substance abuse, domestic violence, and parental separation), can also lead to chronic toxic stress with associated outcomes, leaving room for residual confounding by inadequately controlled history of psychological trauma,” she wrote, noting that this — and many dietary factors — should all be taken into consideration for future studies.

Other limitations, Lu and co-authors said, included that PMD cases were not based on prospective daily symptom tracking, which is not feasible in large cohort studies; and that body size may have been misclassified for some of the individuals, particularly body shape at 5 years of age, which was recalled at baseline.