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The Evidence Speaks

The Evidence Speaks (March 2020)

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The Evidence Speaks Series is a recurring feature highlighting the latest in CHÉOS research. This series features summaries of select publications as well as in-depth features on the latest work from our investigators. The Series is designed to keep media and the research community up-to-date with CHÉOS’ current research results in the health outcomes field.

Proctor L, Grennan T, Albert A, Miller D, Sadownik L, Lee M. Screening for Anal Cancer in Women With a History of Vulvar High-Grade Squamous Intraepithelial Lesions. J Low Genit Tract Di. 2019 Oct;23(4):265-71.

A high-grade squamous intraepithelial lesion (HSIL) is an abnormal area of cells that is often caused by chronic human papillomavirus (HPV) infection. This abnormality can form on the surface of specific organs, such as the vulva, vagina, cervix, and anus, and if left untreated, may develop into cancer. CHÉOS Scientist Dr. Troy Grennan and his colleagues from the University of British Columbia recently conducted a study to determine the prevalence of a positive anal cancer screen and histological anal HSIL in women who are undergoing surveillance for diagnosed and treated HPV-associated vulvar HSIL. The team recruited 57 women for this study, of whom 32 had a positive screen for abnormalities. Of these 32 women, 29 went on to undergo anoscopy, revealing that 33.3% had anal HSIL. This translates to 18.2% of all participants who were screened in this study. The information gathered here indicates that women with vulvar HSIL may be more likely to develop anal HSIL. As such, the researchers recommend that screening for anal cancer should be considered among this population; however, larger studies are needed to define the optimal protocols and algorithms for management.

Muraca GM, Liu S, Sabr Y, Lisonkova S, Skoll A, Brant R, Cundiff GW, Stephansson O, Razaz N, Joseph KS. Episiotomy use among vaginal deliveries and the association with anal sphincter injury: a population-based retrospective cohort study. CMAJ. 2019 Oct;191(42):E1149-58.

Obstetric anal sphincter injury can occur during vaginal delivery and may cause complications such as infection, diminished sexual function, incontinence, and pain. Over the last 15 years, the rate of obstetric anal sphincter injury has increased, especially among women who underwent operative vaginal deliveries. CHÉOS Scientist Dr. Geoffrey Cundiff joined forces with colleagues from Canada, Sweden, and Saudi Arabia to conduct a population-based retrospective cohort study to analyze trends in episiotomy use and determine whether there is an association between episiotomy and obstetric anal sphincter injury. The study population included 2,570,847 deliveries that took place from 2004 to 2017. The results highlighted a decrease in the use of episiotomy among both spontaneous and operative vaginal deliveries in Canada. However, when used, episiotomy was associated with higher rates of obstetric anal sphincter injury in spontaneous vaginal deliveries, whereas in operative vaginal deliveries, the association between episiotomy and obstetric anal sphincter injury varied. In fact, episiotomy lowered the risk of obstetric anal sphincter injury among operative vaginal deliveries in women who delivered vaginally for the first time. These results suggest that generalizing episiotomy guidelines for vaginal delivery may cause harm; however, reconsideration of clinical practice among women delivering vaginally for the first time may be warranted.

Brajic TS, Berger C, Schlammerl K, Macdonald H, Kalyan S, Hanley DA, Adachi JD, Kovacs CS, Prior JC; CaMos Research Group. Combined hormonal contraceptives use and bone mineral density changes in adolescent and young women in a prospective population-based Canada-wide observational study. J Musculoskelet Neuronal Interact. 2018 Jun;18(2):227-36.

An increasing number of adolescent and young adult women are taking combined hormonal contraceptives (CHC) at a time in their life when they may not have yet reached their peak areal bone mineral density (BMD). Normal levels of peak BMD are thought to be vital in preventing fracturing osteoarthritis later in life. Dr. Shirin Kalyan, Scientist at CHÉOS, worked with a cross-Canada team to describe the BMD changes that could be related to CHC, and compare any differences in BMD changes in adolescent (16-19 years) versus young adult (20-24 years) women. The team also examined whether CHC-related BMD changes were related to dose or age at first CHC use. The study enrolled 527 women from across Canada and divided them by age to create the adolescent and young adult groups. At baseline and after two years, each participant completed a questionnaire covering CHC use, age at first CHC use, main reason for CHC use, age at first menstruation, parity, calcium and vitamin D intakes, physical activity, and alcohol and cigarette use. Of the 307 women who completed the study, 75% used CHC. The results suggest that BMD changes are not related to the dose of estrogen in CHC or age of starting CHC. The results also indicate that adolescent CHC users demonstrated less hip region peak BMD accrual than non-users; however, the findings require confirmation via a randomized control trial.