Sitting time, physical activity and cervical intraepithelial neoplasia in Australian women: a preliminary investigation

Abstract

Issue addressed: Physical activity affects the immune system, which in turn may modify the risk of cervical intraepithelial neoplasia (CIN). The effect of sitting on CIN is unknown. This study investigated the relationship between sitting time, physical activity and the risk of CIN. Methods: Community-dwelling adult women within metropolitan Perth, Western Australia, who had had a Papanicolaou (Pap) smear test at any of five clinics and medical centres, were approached by their general practitioners. In total, 348 women were recruited and interviewed for information on sitting time, physical activity level and lifetime physical activity exposure using the International Physical Activity Questionnaire (IPAQ) -short form. Associations of exposure variables with CIN risk were assessed by unconditional logistic regression analyses. Results: The prevalence of abnormal Pap smear status indicating CIN was found to be 15.8%. Women with prolonged sitting duration ( 42 h per week) had significantly increased risk of CIN (adjusted OR 3.49, 95% CI 1.12-10.88) than women who sat less than 24.5 h per week. Although the effect of total physical activity level was non-significant (P = 0.408), being always involved in physical activity during the entire life appeared to be inversely associated with the CIN risk (P = 0.036).

Physical Activity of ≥7.5 MET-h/Week Is Significantly Associated with a Decreased Risk of Cervical Neoplasia

“…More, women with highest physical activity of 72 MET-h/week protected themselves against CIN2/3 and cervical cancer risks compared to women with lowest physical activity of <38.5 MET-h/week [ 21 ]. However, our findings were inconsistent with those of Chih et al [ 20 ], who found that the volume of MET-h/week of physical activity did not significantly differ between women with a normal Pap smear and women with CIN screened by Pap smear [ 20 ]. We suggest that a statistically insignificant difference of MET-h/week of physical activity between women with a normal Pap smear and CIN, may be attributed to the CIN not being confirmed by a biopsy and the small size of the study by Chih et al [ 20 ].…”

“…We suggest that it is necessary to explore the dosage of MET-h/week of physical activity to protect women from cervical neoplasia; however, only a few studies have evaluated the effects of physical activity on the cervical neoplasia risk [ 19 , 20 , 21 ]. Szender et al [ 19 ] recruited 128 patients with cervical cancer and 512 participants who were suspected of having but not ultimately diagnosed with a neoplasm to estimate the effect of physical activity on cervical cancer risk.…”

“…However, they did not provide a suggested dose of physical activity for protecting women from cervical cancer [ 19 ]. Chih et al [ 20 ] recruited 293 women with a normal Papanicolaou (Pap) smear and 55 women with cervical intraepithelial neoplasia (CIN) screened by Pap smear and found that the volume of physical activity did not significantly differ between these two groups [ 20 ]. Lee et al [ 21 ] recruited participants nested within an HPV cohort study to evaluate the association between physical activity and cervical neoplasia.…”

“…Participants with high and medium MET-h/week levels of physical activity exhibited a significant trend of decreasing CIN2/3 and cervical cancer risks compared to participants with lowest tertile MET-h/week levels of physical activity [ 21 ]. Nevertheless, none of the three studies [ 19 , 20 , 21 ] analyzed a stratified effect of physical activity on CIN risk for different smoking exposures and HR-HPV infection statuses, as both smoking exposure and HR-HPV infection are predominant factors inducing cervical neoplasia. The purpose of this study was to investigate whether leisure-time physical activity is sufficient to decrease the risk of cervical neoplasia and provide suggested guidance of MET-h/week levels spent on leisure-time physical activity to prevent cervical neoplasia for the general female population, as well as for specific populations, including women who are non-smokers, are smokers, are exposed to secondhand smoke (SHS), do not have HR-HPV infection and have HR-HPV infection.…”

Impact of Physical Inactivity on Risk of Developing Cancer of the Uterine Cervix: A Case-Control Study

“…While screening is a protective factor against development of cervical cancer, minimal attention has been paid to the effects of physical activity on cervical cancer [7, 8]. The association between physical activity and screening has been attributed to attention to healthy lifestyle decisions; although the difficulty of undergoing screening examinations for patients who have physical disability could also play a role.…”