"These results may have a direct impact on health care delivery if used to develop screening for women at higher risk and to prepare providers to treat women suffering from PFD," researchers said.
Pelvic floor disorders (PFD) impact nearly one-fourth of all adult women in the U.S. and are often associated with decreased physical activity and poor quality of life, but the intense, strenuous activity and psychological stress soldiers often endure may put them at increased risk.
To better understand the rates of PFD in female soldiers on active duty in the U.S. military, researchers analyzed data from the Stanford Military Data Repository (SMDR), which included medical, demographic and military service-related information on all soldiers in the U.S. Army on active duty at any time between January 1, 2011, and December 31, 2014.1
The researchers included traditional covariates known to be associated with PFD as predictors, as well as military-specific characteristics and measures of fitness and health uniquely available in a military cohort. They adjusted for age, recent weight gain, number of children, pregnancy within the last 6 months, body mass index (BMI), race, and ethnicity.
To explore the association between physical fitness and PFD, researchers used scores from the Army Physical Fitness Test, which is composed of counts of push-ups and sit-ups over 2 minutes and a timed 2-mile run graded on a scale up to 300 points and administered twice a year.
The analysis, published in the journal Urology, included 102,015 women aged 18 to 64 years, and the median observation time for each soldier was 29 months (range 1-42 months). For the full 42 months, 34,776 soldiers were present (34.1%) and more than one-third of them were new entrants to active duty. At least 1 PFD was diagnosed in 6,500 women over the observed period (cumulative incidence: 6.4% over the mean follow-up period of 27 months), for an incidence of 28.5 cases per 1000 person-years.
Among 51,008 participants who took the complete physical fitness tests with regular scoring on the 300-point scale, women without PFD had a higher mean score (236, standard deviation [SD] 54.7) than those with PFD (222.6, SD 64.7, P < 0.001).
The findings suggested that risk of PFD increased with age. Women over 36 years old were 74% more likely to have a PFD diagnosis than those younger than 23 (hazard ratio [HR] 1.74, 95% confidence interval [CI] 1.55-1.94, P < 0.001). The study did not provide details for women between the ages of 23 and 36. Similar trends existed for BMI, with obese soldiers more likely to have a PFD compared with those of normal weight (HR 1.23, CI 1.14-1.34, P < 0.001).
Participants with the lowest physical fitness scores were significantly more likely to have a PFD (HR 1.20, CI 1.09-1.32, P <0 .001) compared to those with the highest scores.
The findings also showed a higher PFD risk in women who had never been deployed (HR 1.39, CI 1.26-1.53, P < 0.001) than women with 3 or more deployments. Total service time also was significantly associated with a PFD diagnosis. Women who served at least 10 years were more likely to have a PFD diagnosis than those serving fewer years (HR 1.23, CI 1.09-1.38, P = 0.001).
Women in medical, dental and veterinary medical occupations had a higher risk of PFD (HR 1.27, CI 1.16-1.38, P < 0.001) than those in administrative roles.
After adjusting for other factors, the researchers noted that recent pregnancy was not significantly associated with the hazard of PFD. Results showed, however, an increase in the PFD hazard with an increasing number of child dependents. Women with 3 or more dependents were most likely to have a PFD (HR 1.50, CI 1.38-1.76, P <0.001).
The authors ultimately found that the 2011-2014 incidence of PFD in a cohort of 102,015 active-duty female soldiers was approximately 6.4% over a 2.5-year period.
They confirmed obesity and age as strong predictors, and that women with a service time of at least 10 years put them at increased risk above and beyond the other measured health factors.
The authors noted that these findings “confirm that a soldier’s PFD risk is still impacted by physical changes such as aging and childbirth as is observed in civilians,” and that “identifying characteristics most strongly associated with PFD in servicewomen could enhance screening and prevention efforts.
“These results may have a direct impact on health care delivery if used to develop screening for women at higher risk and to prepare providers to treat women suffering from PFD,” they wrote.