Childhood voiding and defecation dysfunction are common problems in children of all ages worldwide (
1-
5). Our study was conducted to evaluate the frequency of voiding and defecation dysfunction in primary school children in Zahedan in 2016. The results of our study showed that the highest prevalence of fecal incontinence belonged to the age group of 13 (77.1%) and 7 (73%), respectively, and the lowest prevalence belonged to the age group of 10 (39.4%) and 9 (56.3%), respectively. The prevalence of fecal incontinence was not significant among different age groups. The difference in the prevalence of urinary incontinence between girls and boys was statistically significant. The difference in the prevalence of defecation dysfunction between girls and boys was not significant. In the study by Vaz et al., in Brazil, the urinary incontinence label was estimated to be 28% in primary school children, with the highest prevalence among children aged 6 to 8, which is consistent with the present study. The highest prevalence of urinary incontinence in the present study was at the same age range (ie, in children aged 7 years) (
8). In other epidemiological studies, Yuksel et al. reported the lowest rate of urinary incontinence in children of age 14 (4.9%) and the highest in children of 6 (23.1%). Risk factors obtained in this study included a lower level of education in parents, history of urinary incontinence in parents in childhood, having more than 2 roommates, having more than 4 siblings, and history of previous urinary tract infection. As can be seen in the study of Yuksel et al., the highest prevalence of urinary incontinence was in the lowest age group (6 years), which is consistent with the results of the present study (
14).
Also, Loening-Baucke showed that the prevalence rates of fecal incontinence, urinary incontinence during the day, and nocturnal urinary incontinence were 4.4%, 3.3%, and 1.8%., respectively (
2). In another study, Loening-Baucke showed that the prevalence of urinary dysfunction was higher in children from low-income families than in those from middle-income and high-income families. Probably parents with high incomes mostly had a higher level of education; therefore, this can be an advantage in educating and supporting their children (
3). The study by Mohammad Jaafari et al. reported prevalence rates of 38.4% for urinary incontinence and 29% for fecal incontinence in children. In their study, the prevalence of urinary incontinence was higher in boys than girls. There was no statistically significant relationship between different age groups. However, in contrast to the present study, the prevalence of urinary incontinence was not related to gender (
15). In the study of Yuksel et al. (
14), the mean age of children with urinary incontinence was lower than children without urinary incontinence, partially confirming the results of the present study. The prevalence of defecation dysfunction was significantly different based on age and sex. The results of this study are consistent with the study of Chen et al. (
16). Using findings from the history and physical examination, as well as ultrasound and radiography of the bladder, they reported prevalence of 44.2% of defecation in normal individuals without urinary tract infection. Also, in this study, the prevalence of dysfunction was higher among girls than boys (
16).
They also stated that bowel dysfunction had a proven relationship with more usage of computer games and entertainment; thus, we can reduce the prevalence of these dysfunctions by properly educating parents (
14). In a 2017 study, Fazeli found that 19% of children held their urine at least half of the time with various maneuvers (
17). In the study by Mohammad Jaafari et al., as well as in the present study, the prevalence of fecal dysfunction was higher in boys than in girls (
15). In 2012, Cobussen-Boekhorst reported prevalence of 8% of defecation dysfunction in the United States (
18), and Croffie reported prevalence of 28% of constipation in children in Asia in 2006 (
19). Studies that investigated the prevalence of urinary dysfunction (such as nocturnal enuresis) have provided different results, such that,10% in Egypt, 16% in Turkey and 16% in China is, 6% India, 11% Nigeria, 33% Saudi Arabia 28 %. (
14,
17) and 56.9% Zahedan (Iran). Many studies, including those of Miskulin et al. and Carman et al., have reported a higher incidence of enuresis in boys than in girls (
20,
21).
In 2010, Miskulin et al. (
20) examined the prevalence of enuresis in 6- and 7-year-old elementary school children and finally reported a prevalence of 1.2%. In a 2013 study, Zargar et al. (
22) estimated the prevalence of urinary incontinence in children at 14.4%, which was higher in boys than in girls (
22). In a 2013 study, Wolfe-Christensen et al. concluded that the more severe the urinary incontinence, the greater the severity of constipation and psychological problems (
23). Based on the study of Carman et al. and Wolfe-Christensen et al., it seems that the diagnosis of the excretory dysfunction and elimination of the underlying factor are necessary; in this regard, education should be comprehensive and include psychological issues (
21,
23).
In 2021, Sadeghi-Bojd et al. showed that of the 200 children with enuresis, 134 (67%) were girls, and 66 (33%) were boys, which is the same as ours. Fecal incontinence was observed in 99 cases (49%), and 101 (51%) did not have fecal incontinence. Urinary tract infection was observed in 142 children (71%). According to imaging studies, 34 children (17%) with enuresis had congenital kidney abnormalities, and 166 (83%) had no kidney problems (
24).
One of the limitations of our study is that the data were obtained from a questionnaire. Some studies have shown that parents report some symptoms less than the actual amount.
Also, our study represents a small sample of the society, and to generalize it to the whole society, further studies in different parts of the country are highly recommended.
Therefore, we suggest that randomized clinical trials are needed to compare parental reports with objective clinical data.
5.1. Conclusions
The prevalence of defecation dysfunction in school-age children was much higher than in previous studies. This may be due to differences in cultural and geographical environments. Due to the high prevalence of defecation dysfunction in children, it is recommended to have more focus on public education on various types of urinary and fecal dysfunction in urban and rural communities.