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The Prevalence and Correlates of Fissured Tongue Among Outpatients in Andkhoy City, Afghanistan: A Cross-Sectional Study

Authors Hamrah MH , Baghalian A, Ghadimi S, Mokhtari S, Kargar M, Khosrozadeh M, Dahi T, Charkazi A, Hamrah MS , Hamrah MH 

Received 9 June 2021

Accepted for publication 15 July 2021

Published 27 July 2021 Volume 2021:13 Pages 335—342

DOI https://doi.org/10.2147/CCIDE.S323428

Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 3

Editor who approved publication: Professor Christopher E. Okunseri



Mohammad Hassan Hamrah,1,2 Ali Baghalian,1 Sara Ghadimi,1 Saeedeh Mokhtari,1 Mojgan Kargar,3 Maryam Khosrozadeh,1 Toba Dahi,4 Abdurrahman Charkazi,5 Mohammad Shoaib Hamrah,6 Mohammad Hussain Hamrah2

1Department of Paediatric Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran; 2Curative Clinic, Andkoy, Faryab, Afghanistan; 3Department of Paediatric Dentistry, School of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran; 4Abant Izzet Baysal University Faculty of Dentistry, Bolu, Turkey; 5Health Education and Promotion, Environmental Health Research Center, Faculty of Health, Golestan University of Medical Sciences, Gorgan, Iran; 6Shaheed Ostad Esmail”Aslam” Aimaq Hospital, Anadkhoy, Faryab Province, Afghanistan

Correspondence: Mohammad Hussain Hamrah
Curative Clinic Andkhoy, Amir Timor Street, Shari now, Andkhoy, Afghanistan
Email [email protected]

Background: Fissured tongue is a common manifestation of the tongue, marked by the presence of multiple prominent grooves or fissures on the dorsal surface of the tongue. However, there is a lack of studies focusing on the prevalence and factors associated with fissured tongue among patients attending an outpatient clinic in Afghanistan.
Aim: The purpose of the current study was to determine the prevalence and factors associated with fissured tongue and its effects on the general health of adult outpatients in Afghanistan.
Patients and Methods: The cross-sectional survey was conducted among outpatient populations in Andkhoy City, Afghanistan, between September 2019 and December 2019. A convenience technique was applied by including 1182 patient aged 18– 80 years. Socio-economic status, smoking, nass use (smokeless tobacco use) and medical data were collected using face-to-face interviews. We used logistic regression analysis to identify factors associated with fissured tongue. A convenience technique was applied by including patient aged 18– 80 years.
Results: The studied population consisted of 1182 participants, of whom 573 (48.5%) were males and 609 (51.5%) females. The prevalence of fissured tongue was 27.2% (95% CI: 24.7– 29.9%) with males having significantly higher prevalence than females (47.5%, 95% CI: 43.3– 51.6% versus 8.2%, 95% CI: 6.2– 10.7%, p< 0.001). Male participants (OR=7.1, 95% CI: 4.8– 10.3), diabetes mellitus (OR=1.6, 95% CI: 1.1– 2.3) and smokeless tobacco use (OR=12.0, 95% CI: 8.1– 17.6) were the only variables independently associated with fissured tongue.
Conclusion: This study suggested that there was a high rate of fissured tongue among an outpatient clinic in Andkhoy, Afghanistan. Male gender, diabetes mellitus, and nass consumption were associated with fissured tongue. Therefore, these factors might usefully be targeted in local health promotion, prevention and early intervention programs.

Keywords: fissured tongue, prevalence, risk factors, Andkhoy, Afghanistan

Introduction

The tongue is the body’s most complex structure and considered the most important muscular organ in the mouth.1 The tongue has many functions, including taste, phonation, swallowing, breathing, speaking and chewing.2 Systemic disease may first present with tongue pathology or alterations in the tongue which can then lead to numerous systemic diseases.3 There are variations in the presentation and frequency of oral manifestation of systemic diseases. The number of people with oral manifestations of systemic diseases has been predicted to increase.4 The elderly are likely to have various manifestations associated with systemic diseases, that could affect the oral health care.5

Fissured tongue, or scrotal tongue or lingua plicata, is a common manifestation of the tongue which is distinguished by a deep, prominent groove on the dorsum of the tongue.6 Fissures on the tongue vary in depth and can be shallow or deep. A cracked tongue can trap food, it can lead to localized inflammation, a burning sensation of the tongue and bad breath.7,8

Diagnosis can best be made through oral examination and personal history.9 The prevalence of fissured tongue varies across the country, generally affecting between 10% and 48.4% of the population.10–14 Previous studies have shown that fissured tongue is correlated to inheritance, candidiasis, the use of smokeless tobacco (in Afghanistan smokeless tobacco is known as nass) and systemic diseases including hypertension, psoriasis, orofacial granulomatosis and diabetes mellitus (DM).15–18

There is a paucity of data relating to the prevalence and factors associated with fissured tongue among Afghan adults living in Afghanistan. A point to consider is the access to health services which is particularly poor in parts of rural Afghanistan.19 This study was conducted to highlight the impact of limited access to health services in these areas. The aim of this study was to determine the prevalence and factors associated with fissured tongue among patients visiting an outpatient clinic in Andkhoy, Afghanistan.

Patients and Methods

Study Population and Setting

The cross-sectional survey was conducted among outpatient populations in Andkhoy, a city in the northern part of Afghanistan. Andkhoy is a district in the Faryab Province of north-western Afghanistan with an approximate population of 37,100. The district is located in the northern part of the province.20 This clinic is an outpatient service for people who need to see a specialist, and it provides patients with care, ongoing management and referrals to other services, if needed. The clinic is also a referral centre in Faryab province in the northern part of Afghanistan.

Study Design and Period

A convenience technique was applied by including patient aged 18–80 years. The cross-sectional survey was conducted among outpatient populations in Andkhoy city, Afghanistan, between September 2019 and December 2019.

Sample Size Determination

The study samples from permanent residents of Andkhoy district. Data was obtained from 1182 patients. Due to the unavailability of previous estimate of prevalence of the correlates of fissured tongue among outpatients in Andkhoy city and considering the prevalence of fissured tongue and their associated factors in similar setting, the number of subjects is due to be 600, and after taking into account the design effect (DE=2) of cluster sampling, the final sample size is expected to reach to 1200 which is reasonable for achieving study objectives. This study was conducted in accordance with the Declaration of Helsinki.

Data Collection Tools and Techniques

Surveys were conducted by interviewers face-to-face using the WHO STEP-wise questionnaire.21

The clinical examinations were performed by the trained doctors. Patients with limited mouth opening and patients who were unable to protrude the tongue were excluded from the study.

Validity and Reliability

Translation involved translating the English questionnaires into Dari (target language) by independent bilingual translators. Additionally, the Persian version of the WHO STEP-wise questionnaire was used, and the questionnaire has been validated.22 Persian and Dari are mutually intelligible varieties of the same language. The questionnaire was also tested on thirty patients to examine its utility and effectiveness. Clarifications were made in questions where needed (the sample used in the pilot study was not included in the main study).

Data Collection Procedure

Informed consent was received from all patients, and they were advised that their participation was voluntary and anonymous. The study was approved by the Faryab Public Health Directorate, Afghanistan. The study assessed socio-demographic variables including age, gender, education, job, and tobacco use (cigarette smoking and nass use). Questions were asked about the patients’ tongue symptoms associated with systemic diseases such as tongue burning. Patients were assessed with a comprehensive history and physical examination. While in a seated position, the patients were assessed using a straight probe, a light and a mouth mirror. The examination of the oral cavity was performed using sterile gloves, sterile gauze and wooden tongue depressor. The patients were asked to protrude the tongue and to perform maximal mouth opening. No biopsy was performed. Classification of fissured tongue was assigned according to the pattern of the fissure. Patients with a fissured tongue were classified into the following types in accordance with pattern of tongue fissures. a. Central longitudinal pattern, b. Central transverse pattern, c. Lateral longitudinal pattern, d. Branching pattern, and e. Diffuse pattern.18 The participants were divided into four groups according to their smoking status: current smokers, past smokers, and non-smokers. Current smokers were defined as patients who have smoked at least 100 cigarettes in their entire life and have smoked during the past 30 days. Past smokers were defined as patients that have smoked at least 100 cigarettes in their entire life and but have not smoked during the past 30 days. Non-smokers were defined as patients who have never smoked a cigarette or had smoked less than 100 cigarettes in their lifetime. Since the number of past smokers was very low, past smokers and never smokers were considered in the non-smokers group in this study.23 Nass’ is a smokeless tobacco product widely used in Afghanistan, Iran, Pakistan and the Central Asian Republics. Nass consists of tobacco leaves, lime, cotton oil or sesame oil, and ash. Nass is consumed by placing it in the mouth cavity, usually between the oral mucosa and gingival cavity or sometimes under the tongue.24 Patients were classified into four categories according to their nass use: non-nass users, past nass users, and current nass users. Non-nass users were defined as patients that have not used nass in their lifetime. Past nass users were defined as patients that have quit nass use at least one month ago. Current nass users were defined as patients who have not used nass more than 20 times in their lives and use nass every day or only occasionally (Note from J: I wasnt sure what you meant here, so I am just guessing).25 Since the number of past smokers was very low, both past nass users and never nass users were constituted in the non-nass user’s category.

Hypertension was defined as a blood pressure at or above 140/90 mm Hg on two separate measurements or are taking medications for hypertension.26 DM (diabetes mellitus): A fasting blood glucose≥126 mg/dL, or a random blood glucose level of ≥ 200 mg/dL, or on the treatment of antidiabetic drugs therapy.27

Data Analysis

Statistical analysis was performed using SPSS software ver. 22.0 (IBM, Armonk, NY, USA). A descriptive analysis was conducted on participant characteristics using frequencies, means, ± standard deviation (SD) and 95% CI (confidence interval). Chi-square tests were done to investigate the associations between fissured tongue and socio-demographic variables, include, age, sex, education, occupation, tobacco use (cigarette smoking and nass use); systemic diseases, namely, hypertension and DM. Univariate associations between fissured tongue and each of the above-mentioned variable variables were first assessed using a series of univariate logistic regression analyses. All variables that might be a risk factor or might lead to fissured tongue were considered as the independent variables including sex, age groups, education level, marital status, occupation, smoking, nass use, hypertension and DM. Any variable was significantly associated with fissured tongue in the univariate logistic regression analysis were selected as a candidate for the multivariate analysis. P value of < 0.05 was considered statistically significant.

Results

The studied population consisted of 1182 patients, of whom 573 (48.5%) were males and 609 (51.5%) females. The overall prevalence of fissured tongue among participants was 27.2% (95% CI: 24.7–29.9%), with males having significantly higher prevalence than females (47.5%, 95% CI: 43.3–51.6% versus 8.2%, 95% CI: 6.2–10.7%, p<0.001). Participants with fissured tongue had significantly higher levels of nass use than those without fissured tongue (68.2% versus 12.8%, p<0.001). The fissured tongue was significantly higher among participants who were smokers (44.8% versus 21.8%, p<0.001). Participants with a fissured tongue had higher levels of hypertension (33.0%), and DM (42.1%%) than those who did not. Fissured tongue was common among participants with other types of jobs (38.3%).

Table 1 shows the socio-demographic and related characteristics of the participants.

Table 1 Socio-Demographic and Clinical Variables of Patients with and without Fissured Tongue

Most participants with fissured tongue were asymptomatic. In our study, the most common type of fissured tongue was the central longitudinal pattern (42.9%), whereas the lateral longitudinal pattern was the least tongue fissured type in the study sample (8.4%). The distribution patterns of fissured tongue in our study is shown in (Figure 1).

Figure 1 The distribution patterns of fissured tongue among study participants.

Table 2 indicates the results from a multivariate logistic regression analysis of the associations between fissured tongue, sex, occupation, smoking, nass use, DM, and hypertension. The likelihood of having fissured tongue was 7.1 times higher among male participants than those of female participants (95% CI: 4.8–10.3). Nass users (OR, 12.0 95% CI: 8.1–17.6), and DM (OR 1.6, 95% CI: 1.1–2.3), were also found to have higher odds to have fissured tongue.

Table 2 Multivariate Logistic Regression Analysis of Variables Correlated to with Fissured Tongue Among Study Sample

Discussion

It is worthy to note that this is the first study to investigate the prevalence and factors associated with fissured tongue among outpatients in Andkhoy City, Afghanistan. The findings suggest that fissured tongue is common in this population, with more than one quarter (27.2%) patients having fissured tongue. The findings of our study suggested that the prevalence of fissured tongue was high among outpatients in Afghanistan, with males having a significantly higher prevalence than females, and were also associated with housewives, nass users, non-smokers, hypertensive and diabetic patients. In multivariate analysis, male gender, DM, and nass use were the variables most strongly associated with fissured tongue.

Among patients attending the outpatient clinic in Andkhoy, Afghanistan, fissured tongue was found in (27.2%) of the total sample. This finding is lower than previous research conducted among patients in the department of Oral Medicine and Oral Diagnosis at the Faculty of Dentistry, Benghazi Libya (48.4%).14 However, the results of this study showed that the prevalence of fissured tongue was higher than that found in patients attending the Department of Oral Medicine and Radiology, Jodhpur Dental College General Hospital in India (14.9%).13 Differences in the rates of fissured tongue could be attributable to variations in the characteristics of participants, race, and ethnicity in the studies sampled.

In this study, we found that the smoking prevalence of fissured tongue was higher among men than women. A similar finding has been reported in another study among outpatients in India.13,28 However, the opposite pattern is seen for Indian and Brazilian outpatients.10,29 Our findings support the hypothesis that males encountered a higher burden of fissured tongue compared to females. A possible explanation for the preponderance of fissured tongue among males in our study can be explained by the higher prevalence of nass use by males, whereas because of cultural constraints, females are less likely to use nass. Of the 1182 study population examined, 230 male participants had a habit of nass use, while 78 females were recorded as nass users, and participants with fissured tongue had significantly higher levels of nass use than those without fissured tongue.

In multivariate analysis nass use was the variable most strongly associated with fissured tongue comparable to previous studies in the Southwest of Sweden.16 It is believed that SLT (smokeless tobacco), may result in oral tissue changes due to local irritation effect among SLT users. This could be attributed to injury to the oral epithelium caused by SLT products and their ingredients.30 A previous study has found that a high risk of cancer is linked to the toxic chemicals in nass.31 Nass causes local tissue trauma in the mouth, throat and tongue by erosion.32 Saeed et al has shown that high degree of toxic heavy metals could be attributed to using ashes and lime in nass.31 These findings suggest that there is a correlation between nass use and fissured tongue. This implies it may be a possible to decrease the harmful effects of nass use by helping patients to quit using nass.

The study shows that diabetes is an independent risk factor for fissured tongue. These findings are comparable to the results of studies among outpatients in India and Pakistan.33,34 An illustration of the relationship between diabetes and fissured tongue could be inadequate blood glucose control, immunological changes, microcirculatory alternation with decrease of blood flow, xerostomia and alteration in salivary flow and composition.33,35,36

Limitations

Overall, the current study has some limitations: Firstly, it is a single centre study, which limits the possibility of generalizing to all the people in Afghanistan. Secondly, the sample was non-random which may affect its overall power. Furthermore, the sample was selected using convenience sampling which limited the generalizability of the results. Finally, cross-sectional studies cannot be used to determine causal relationships with risk factors associated with fissured tongue. One of the strengths of this study is that it can be valuable for the accumulation of further data on the prevalence of fissured tongue and studies of variables potentially correlated to fissured tongue in Afghanistan. Additionally, study populations could be replicated in other study.

Conclusions

In conclusion, the study revealed a high prevalence of fissured tongue in an outpatient clinic in Andkhoy, Afghanistan with males having significantly higher prevalence than females. This study has found that being of male gender, DM and nass consumption were most important determinates of fissured tongue among an outpatient clinic in Afghanistan. This study suggests that for oral health promotion and illness prevention there is urgent need for an early intervention program particularly these targeting factors.

Data Sharing Statement

Research data not shared.

Acknowledgments

Our study project was supported by the Terumo Life Science Foundation.

Disclosure

The authors report no conflicts of interest in this work.

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