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| ORIGINAL ARTICLE |
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| Year : 2016 | Volume
: 3
| Issue : 2 | Page : 90-96 |
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Association between tobacco consumption and periodontal diseases among type 2 diabetes mellitus patients
Shaikh Zakir Mahmud1, Mohammad Shoheilul Amin2
1 Department of Dentistry, Ibrahim Gerenral Hospital-Mirpur, Mirpur, Dhaka, Bangladesh
2 Department of Oral Pathology and Periodontology, Pioneer Dental College, Dhaka, Bangladesh
| Date of Web Publication | 9-Aug-2016 |
Correspondence Address:
Shaikh Zakir Mahmud
Ibrahim Gerenral Hospital-Mirpur, Commercial Plot No. 27-28, Block-Kha, Main Road-1, Section-6, Mirpur, Dhaka-1216
Bangladesh
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/1658-6816.188082
Background: Tobacco use may be an independent, modifiable risk factor for impaired glucose tolerance, and noninsulin-dependent diabetes mellitus. The use of both combustible and noncombustible forms of tobacco increases the risk of coronal and root caries, periodontal diseases, and oral cancer.
Aims: This cross-sectional study was conducted to find out the relationship between tobacco consumption and occurrence of periodontal diseases among type 2 diabetes mellitus patients.
Subjects and Methods: A total 120 type 2 diabetic patients attended at a diabetic center for routine check-up over a period of 6 months fulfiled the eligibility criteria were selected consecutively. To get the target sample quickly non-randomized purposive sampling technique was followed using a pre-tested semi-structured questionnaires and a checklist. The severity of periodontal diseases was followed according to American Academy of Periodontology (1999). The data were analyzed using the software SPSS, Version 11.5 (SPSS Inc., Chicago, IL, USA). software. Associations were assessed using the Chi-square test and logistic regression analysis.
Results: Among the participants 22.5% were current smoker and 31.7% always chewed betel leaf. Education level indicated strong association with chewing betel leaf on unadjusted (odds ratio = 0.56 [0.39–0.82]) (P < 0.003). Chewing betel leaf (Paan) was significantly associated with the occurrence of periodontal diseases (P = 0.048). In addition, knowledge about cigarette smoking and chewing tobacco increases periodontal diseases indicated strong associations with current smoker as well as betel leaf chewer (P = 0.000).
Conclusions: The relationship between smoking and chewing betel leaf and periodontal diseases provide strong evidence that tobacco products could be in a straight line responsible for developing periodontal diseases. Keywords: Diabetes mellitus, noncommunicable diseases, periodontal diseases, tobacco consumption
How to cite this article:
Mahmud SZ, Amin MS. Association between tobacco consumption and periodontal diseases among type 2 diabetes mellitus patients. Saudi J Oral Sci 2016;3:90-6 |
How to cite this URL:
Mahmud SZ, Amin MS. Association between tobacco consumption and periodontal diseases among type 2 diabetes mellitus patients. Saudi J Oral Sci [serial online] 2016 [cited 2023 Apr 2];3:90-6. Available from: https://www.saudijos.org/text.asp?2016/3/2/90/188082 |
| Introduction | |  |
Tobacco use is an important modifiable risk factor common to major noncommunicable diseases (NCDs) - cancer, cardiovascular diseases, chronic respiratory diseases, and diabetes, causing 1 in 6 of all NCD deaths. Almost 6 million people die from tobacco use each year, both from direct tobacco use and second-hand smoke. By 2020, this number will increase to 7.5 million, accounting for 10 million deaths.[1] Tobacco refers to the more than 70 plant species within the genus Nicotiana of the Solanaceae (nightshade) family, as well as to products manufactured from dried tobacco leaves, including cigars and cigarettes, snuff, pipe tobacco, chewing tobacco, and flavored shisha.[2],[3] The pattern of use of smokeless tobacco in developing countries is less documented when compared with the pattern of tobacco smoking.[4] Tobacco smoke released into the environment by smokers commonly referred to as environmental tobacco smoke and which is responsible for “passive smoking” has several deleterious effects on people who inhale it.[5] Chronic secondhand smoke exposure (passive smoking) significantly increases the risk for type 2 diabetes.[6] In Bangladesh, current tobacco use (smoking or smokeless) among all adults is 41.3 million. The proportion is higher in males than females. Tobacco use is more prevalent in rural areas than urban areas and among persons with no formal education and in the lowest quintiles of socioeconomic status.[7]
The dire consequences of having type 2 diabetes and continuing to smoke have been appreciated for decades.[8] The cardiovascular burden of diabetes, especially in combination with smoking, has not been effectively communicated to both people with diabetes and healthcare providers. Smoking is also related to the premature development of microvascular complications of diabetes and may have a role in the development of type 2 diabetes.[9] The magnitude of this public health challenge is growing, and estimates suggest that as many as 10 million people may die from smoking-related causes in 2025. The prevalence of diabetes is also expected to have a major increase by the year 2025, a concerning trend given that diabetes imposes a significant public health burden and large demands on health care systems.[10] After decades of studies, accumulating lines of epidemic evidence have suggested that chronic smokers have a higher risk to be insulin resistant, exhibit several aspects of the insulin resistance syndrome, and develop type 2 diabetes mellitus (T2DM).[11]
Tobacco use has seriously damaging effects on nearly every system in the body. The first area of the body to be affected by tobacco is the oral cavity. The use of both combustible and noncombustible forms of tobacco increases the risk of coronal and root caries, periodontal disease, and oral cancer.[12] There is strong evidence that tobacco use leads to oral mucosal lesions, including oral pre-cancerous lesions, and gingival recession.[13] People with diabetes who use tobacco have more chance of getting gum disease and may suffer tooth loss.[14] In a study the combination of diabetes and heavy smoking in an individual over the age 45 years resulted in an odds ratio (OR) of periodontal attachment loss 30 times that of a person lacking these risk factors.[15] Chronic exposure from smokeless tobacco has been reported to cause neuromuscular disease manifested as a loss of muscle bulk, strength, and endurance. Tobacco amblyopia, a gradual loss of visual acuity of bright light secondary to nicotine absorption, has been seen in smokeless tobacco users as well as in smokers. The presence of salt, glucose, and flavorings present in smokeless tobacco may affect the therapeutic regimen of certain groups of patients such as hypertensives, patients with congestive heart failure, and diabetics.[16] Due to wider availability and ease of use without getting attention, chewing smokeless tobacco with betel leaf has attracted smokers who want to quit, young children, and women.[17] In India and Bangladesh, it is observed that due to the rampant use of paan masala by persons of all age groups and both the sexes' periodontal disease prevalence will increase then projected.[18] This will create a perfect storm of future tobacco-caused disease and death unless there is a strong response from the public health community.[19] Health professionals (physicians, dentists, nurses, and health workers) could play a major role to prevent illness and preterm deaths due to tobacco use.[20]
The need of this study is to evaluate the effects of tobacco consumption on periodontal health among diabetic patients.
| Subjects and Methods | | |
This analytic type of cross-sectional study was conducted to assess the proportions of periodontal diseases in relation to tobacco consumption among T2DM patients attending at National Healthcare Network (NHN) Mirpur Centre which is an Enterprise of Diabetic Association of Bangladesh, Dhaka. The study was carried out among type 2 diabetic patients who were suffering from different periodontal diseases and attended this diabetic center for routine checkup over a period of 6 months from September 2011 to February 2012. To get the target sample quickly non randomized purposive sampling technique was followed by using a pre-tested semi-structured questionnaires and a check list.
The required sample size was calculated according to the following simple formula that was used:[21]
where,
n = required sample size,
z = confidence level at 95% (standard value of 1.96)
p = expected prevalence or proportion of chronic gingivitis in the project area, and
d = precision or margin of error at 5% (standard value of 0.05).
For estimation of sample size, a preliminary estimate of P = 85.5% was made based on a previous study.[22] Taken prevalence (p) of chronic gingivitis as 85.5% = 0.855 in the study group and confidence level (z) of 95% = 1.96 with accepting margin of error (d) at 5% = 0.05, the calculated sample size (n) was 191. However due to time and financial constraint, 120 sample sizes were taken which was practical and achievable.
Inclusion criteria were:
- Patients aged more than 35 years diagnosed with T2DM
- Patients having glycosylated hemoglobin level equal to or more than 7.0%.
Exclusion criteria were:
- Those who refused to provide consent after having been informed about the purpose of the study
- Persons with co-morbid psychiatric conditions (i.e., drug abuse, suicidal ideation, and psychosis
- Physically challenged patients.
Informed consent was obtained from each single subject included in the study. All the subjects were examined by a single examiner. The observations and readings were recorded in a printed proforma. The classification of periodontal diseases was followed according to American Academy of Periodontology (AAP) (1999) and was recorded: (1) Gingivitis, (2) periodontitis, (3) necrotizing periodontal diseases, (4) periodontal abscesses, (5) periodontitis with the endodontic lesion.[23] Chronic gingivitis is, with few exceptions, the preliminary stage of the development of chronic periodontitis, but clinically no sharp dividing line can be drawn between chronic gingivitis and periodontitis.[24] For this region, to differentiate periodontitis from gingivitis, the periodontal index was followed according to Ramfjord (1967) while assessment of gingivitis was done according to Loe and Silness index (1967). The severity of periodontitis was assessed clinically by measuring the depth of periodontal pocket using periodontal probe graduated in millimeters was passed through the pocket up to the bottom. The probe was placed parallel to the long axis of the individual tooth at six sites, and the depth of the periodontal pocket was taken. The pressure during probing was exerted within the range of 20–25 g.
Data were checked, cleaned, and edited properly before analysis. The data were analyzed using the software SPSS, Version 11.5 (SPSS Inc., Chicago, IL, USA). Impact of factors (such as age, gender, family income, educational status, occupation, residency, smoking status, and tobacco chewing status) was assessed by logistic regression analysis. The relation between each factor and Periodontal Diseases was assessed using the Chi-square test. A significance value of P < 0.05 was accepted as statistically significant.
| Results | | |
The frequency of patients' sociodemographic characteristics in relation to the current smoker and chewing betel leaf is provided in [Table 1]. Maximum 34.2% were in the age group of 36–45 years and 7.5% showing the minimum were age group of more than 65 years. Female participants were 60.8% whereas male were only 39.2%. The majority 90.8% were Muslim followed by 5.8% Hindu, 2.5% Christian and the rest 0.8% showing minority were Buddha. Highest 45% among the patients whose family income were in between 16 and 20,000 BDT per month and 4.1% showing lowest were more than 30 thousand BDT. About 25% of patients were illiterate although 21.7% completed graduation. Likewise, 15% completed primary, whereas 14.2% completed SSC or equivalent. Furthermore, 13.3% completed secondary and 10.8% showing the lowest completed HSC or equivalent. Maximum 45.8% were housewives and minimum 1.7% were farmers. Most of the patients (64.2%) were living in urban followed by 14.2% in rural, 13.3% in slum and 8.3% in sub-urban, respectively. In addition, patients' sex, religion, and occupation were significantly associated with current smoker as the P values were 0.000, 0.012, and 0.000, respectively. Moreover, patients' sex, education level, occupation, and residency were significantly associated with the habit of chewing betel leaf as the P values were 0.006, 0.000, 0.004, and 0.019, respectively. | Table 1: Distribution of the patients according to sociodemographic characteristics, in relation to current smoker and betel leaf chewer (n=120)
Click here to view |
The logistic regression of patients' sociodemographic characteristics, in relation to the current smoker and chewing betel leaf are provided in [Table 2] and [Table 3], respectively. Here, only education level seems to be protective factor and is statistically significant with chewing betel leaf (P < 0.003, OR = 0.56, 95% confidence interval [CI] =0.39–0.82) on unadjustment. | Table 2: Logistic regression of patients' sociodemographic characteristics in relation to current smoker (n=120)
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 | Table 3: Logistic regression of patients' sociodemographic characteristics in relation to chewing betel leaf (n=120)
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The distribution of the patients according to tobacco-related habit variables, in relation to periodontal diseases is shown in [Table 4]. Here, 22.5% were current smoker and 31.7% always chewed betel leaf. Betel leaf chewer, chewing tobacco with betel leaf and knowledge about smoking as well as chewing tobacco rises periodontal diseases were significantly associated with the occurrence of periodontal diseases as the P values were 0.048, 0.044, and 0.024, respectively. | Table 4: Distribution of the respondents according to tobacco related habit variables, in relation to periodontal diseases (n=120)
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Association between patients' knowledge about cigarette smoking and chewing tobacco increases periodontal diseases in relation to the current smoker and betel leaf chewer are provided in [Table 5] and [Table 6], respectively. The highly significant association found between current smoker and knowledge about cigarette smoking as well as chewing tobacco increases periodontal diseases (P = 0.000). On the contrary, knowledge about cigarette smoking and chewing tobacco increases periodontal diseases indicated a highly significant association with betel leaf chewer (P = 0.000). | Table 5: Association between knowledge about cigarette smoking and chewing tobacco increases periodontal diseases and current smoker (n=120)
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 | Table 6: Association between knowledge about cigarette smoking and chewing tobacco increases periodontal diseases and betel leaf chewer (n=120)
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| Discussion | | |
This cross-sectional study was conducted to investigate the relationship between tobacco consumption and periodontal diseases among T2DM patients among Bangladeshi population. To minimize bias due to misclassification of diabetes type, this study included only those subjects 35 years of age and older because it is recognized that over 95% of individuals with diabetes who are 35 years of age and older have T2DM. Diabetic patients were selected by purposive sampling from NHN Mirpur Centre located in Dhaka City.
The classification of periodontal diseases followed in this study is based on AAP has been widely used to evaluate the severity of periodontal diseases in epidemiological studies. This classification is easy to use since the criteria are objective, the examinations can be carried out quickly and a high level of reproducibility is possible with minimum training. For these reasons, the AAP classification of periodontal diseases was chosen for this study.
In Bangladesh, global adult tobacco survey was conducted in 2009 as a household survey of persons 15 years of age or older by the National Institute of Preventive and Social Medicine in collaboration with the Bangladesh Bureau of Statistics and National Institute of Population Research and Training. Here, 43.3% of adults currently use tobacco in smoking and/or smokeless form. Of them, 58% were men and 28.7% were women. 44.7% of men, 1.5% of women, and 23.0% overall currently smoke tobacco. 26.4% of men, 27.9% of women, and 27.2% overall currently use smokeless tobacco.[7] Tobacco use was also high among the laborer (OR = 8.541; 95% CI = 2.422–30.120) and businessmen (OR = 7.727, 95% CI = 2.501–23.875). Statistically significant association was found between current tobacco use and level of occupation (P = 0.001).[25] High prevalence of smoking (22.8%) and the use of smokeless tobacco (43.4%) were observed among rural men compared to urban men (smoking - 12.8% and smokeless tobacco consumption-23.1%).[26] In this study, most of the patients (64.2%) were living in urban followed by 14.2% in rural, 13.3% in slum, and 8.3% in sub-urban, respectively. Moreover, patients' sex, religion, and occupation were significantly associated with current smoker as the P values were 0.000, 0.012, and 0.000, respectively. In addition, patients' sex, education level, occupation, and residency were significantly associated with the habit of chewing betel leaf as the P values were 0.006, 0.000, 0.004, and 0.019, respectively [Table 1].
A study was conducted to examine predictors of current tobacco smoking and smokeless tobacco use among the adult population in Bangladesh. Correlates of current smoking are male gender (OR = 41.46, CI = 23.8–73.4), and adults in older age (ORs range from 1.99 in 24–35 years age to 5.49 in 55–64 years age), less education (ORs range from 1.47 in less than secondary to 3.25 in no formal education), and lower socioeconomic status (ORs range from 1.56 in high wealth index to 2.48 in lowest wealth index). Predictors of smokeless tobacco use are older age (ORs range from 2.54 in 24–35 years age to 12.31 in 55–64 years age), less education (ORs range from 1.44 in less than secondary to 2.70 in no formal education), and the low (OR = 1.34, CI = 1.0–1.7) or lowest (OR = 1.43, CI = 1.1–1.9) socioeconomic status.[27] In this study, logistic regression of patients' socio-demographic characteristics, in relation to current smoker had not a single association [Table 2]. On the contrary, only education level (P < 0.003, OR = 0.56, 95% CI = 0.39–0.82) indicated a strong association with betel leaf chewer [Table 3]. These may be due to less number of sample sizes which decreases the power of the statistical tests.
Researchers' analysis found that both smoking status and amount of subgingival calculus had significant associations with severe periodontal disease.[28] Several studies found that smoking increases the risk of periodontal diseases by nearly 10 times in diabetic patients.[29],[30],[31] A study conducted in the United States in 2000, reported that approximately 40% of periodontitis cases (6.4 million cases in the US adult population) were attributable to patients' smoking habits with a further 10% (1.7 million cases) being attributable to former smoking. This equates to half of these adult periodontitis cases being associated with a smoking habit.[32] Accordingly, it was found in the current study that 22.5% of the respondents were current smoker even though 44.2% of them had knowledge about cigarette smoking and chewing tobacco is bad for health and raises periodontal diseases as well. However, no significant relationship found between current smoker and periodontal diseases [Table 4]. This is may be due to less number of male smokers among the study population. On the contrary,a highly significant association found between current smoker and knowledge about cigarette smoking and chewing tobacco increases periodontal diseases as the P = 0.000 [Table 5].
Many studies have been undertaken to highlight the link between betel leaf (Paan) chewing and periodontal diseases, with many authors stressing that the effects on periodontal diseases and periodontal therapy are heavily influenced by chewing betel leaf (Paan). The toxic components of smokeless tobacco (mainly nicotine) may also directly or indirectly cause the deterioration of periodontal tissues.[33] People who use betel nut have a greater tendency to have periodontal disease, fibrous tissue in the mouth and throat and inflammation and cancer in the mouth. Betel nut chewers may have a higher risk of developing type 2 diabetes.[34] In more recent population-based studies in Taiwan, betel nut chewing is also associated with a higher risk of T2DM.[35] Nevertheless, data analysis from this study showed that although 45% of the respondents had knowledge about cigarette smoking and chewing tobacco is bad for health and raises periodontal diseases as well, about 31.7% of them always chewed betel leaf (Paan). Among them, 14.2% chewed smokeless tobacco with betel leaf, whereas 17.5% did not chew betel leaf with smokeless tobacco. Moreover, chewing betel leaf (Paan) and chewing smokeless tobacco with betel leaf were significantly associated with the occurrence of periodontal diseases as the P values were 0.048 and 0.044, respectively [Table 4]. What is more, a positive association found between betel leaf chewer and knowledge about cigarette smoking and chewing tobacco increases periodontal diseases as the P = 0.000 [Table 6].
Limitations
This study would have needed a much larger sample size to generalize the results in Bangladeshi population. As there was limited time frame and resources to conduct the study, we used the most convenient formula for calculating the sample size. Therefore, the sample size became smaller which may decrease the statistical power.
Other limitation of this study was the veracity of the data collection by purposive sampling method using a semi-structured questionnaire.
In this investigation, the homogeneity of the sample could not be ensured. For instance, respondents from the sex groups were not equal in number. Again, socioeconomic backgrounds of the patients were varied, as the family income depends on the number of persons employed.
Tobacco-related behavior mentioned in the questionnaire may differ from actual behavior, as the respondents have full authority to answer the questions as they liked and there was no system for cross check during this study.
| Conclusion | | |
The statistical data provides evidence that tobacco products could be in a straight line responsible for developing periodontal diseases. The public should be aware of the high risk of periodontal diseases attributed to use above mentioned substances. Further studies are required in other diabetic hospitals and centers to demonstrate the similar effects of this consumption to find out the actual prevalence of periodontal diseases to get an idea of the burden of the underlying health problem. There is a need for appropriate prevention and planning strategies for both combustible and noncombustible forms of tobacco users among diabetic patients.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]
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