Normal Values of High Resolution Anorectal Manometry in 132 Romanian Healthy People

Background & Aims: The primary method for assessing anorectal function is high resolution anorectal manometry (HRAM). It is a useful tool in the diagnosis of different anorectal functional disorders such as fecal incontinence or dyssynergia. The aim of the present study was to propose a new set of normal values to be used in practice for East-European individuals, as it was proven that the results are highly influenced by race and sociocultural status. Methods: We conducted a study based on anorectal manometric values of healthy volunteers analyzed at Clinic Fundeni Institute, Bucharest, Romania, between 2017 and 2022. The anorectal manometry was performed using a solid-state catheter (Diversatek, 23 pressure sensors). All anorectal measurement values were analyzed using the Bioview Software Analysys, respecting the timing and the order from the standardized IAPWG protocol. Manometric measurements were summarized using mean, median, standard deviation, minimum and maximum values. The impact of age and gender on 8 different manometric parameters was further analyzed. Normal ranges for all numeric variables were estimated using the 5th and 95th percentiles of the measurements. Results: A total of 132 subjects (97 females, 35 males) were enrolled in the study. Median age was similar between groups (54 vs. 55 years). The values for rectal propulsion, anal gradient and anal relaxation proved to be higher in females under 54 years as opposed to older women. The values for resting pressure, maximum squeeze pressure, incremental squeeze pressure were significantly higher in males younger than 54. Regardless of age, values for maximum squeeze pressure, incremental squeeze pressure, duration of squeeze and rectal propulsion were found to be significantly higher in males than in females. Normal values of HRAM in healthy volunteers are presented in a table at the end of the study. Conclusions: The data presented in the current study are of high value and have a great impact on clinical practice, being the first study offering a spectrum of the normal values for HRAM in an Eastern Europe population.