Risk indicators for periodontal disease and tooth loss among two rural communities in India.

Introduction: Chronic periodontal disease is a frequently occurring disease among middle-aged adults. It results from a complex interplay of host, environmental and local factors. There are no published data on the risk indicators for periodontal disease in rural Indian populations. Hence, the present study was conducted to identify the risk indicators for periodontal disease and tooth loss in two rural populations, which were diverse in nature with respect to their occupation, education, habits and diet. The hypotheses of the study were as follows: 1. Prevalence, extent and severity of periodontal disease and tooth loss vary between the fishing and farming communities. 2. Tobacco use, psycho-social factors, alcohol consumption, diet and poor oral hygiene are risk indicators for periodontal disease in the Indian rural population. 3. Risk indicators for periodontal disease show clustering in the Indian rural population. 4. Tooth loss is associated with dental visiting behaviour in the Indian rural population. Methods: This was a cross-sectional population-based study. Two coastal districts in rural Karnataka state where the fishing and farming populations formed a majority were chosen for the study. A multistage (stratified cluster random) sampling design was followed. Men and women in the age group of 35-54 years were randomly selected and recruited in each cluster. Data were collected by conducting face-face interviews and oral examinations for consenting participants. For statistical analyses, prevalence, extent, and severity of periodontal disease and prevalence of tooth loss were the primary outcomes. Univariate, bivariate and multivariate analyses using analytical techniques for stratified clustered sampling were used to identify significant risk indicators. The risk indicators were quantified by calculating the prevalence ratios from multivariable models. Propensity score adjustment was used to control for potential selection bias in evaluating the risk indicators for tooth loss. The population impact of the risk indicators were estimated using population attributable fraction (PAF). Results: The response rate in the study was 62.3%. During the study period, 1401 eligible participants from 50 villages of two coastal districts were approached. Of the total 873 participants, 522 were from the fishing and 351 were from the farming communities. The prevalence of periodontal disease was 46.6% in the total rural population according to the Centre for Disease Control and Prevention and the American Academy of Periodontology (CDC-AAP) case definition. Both communities had similar levels of periodontal disease measured by prevalence, extent and severity. Patterns of health behaviours varied between subgroups by socioeconomic status (SES). The prevalence of tobacco chewing was high in both communities. Farming people had better SES compared to the fishing population. Age, dental plaque, SES, method of cleaning, tobacco chewing and alcohol were the significant risk indicators in the models for prevalence, extent, and severity of periodontitis. Clustering of risk indicators for periodontal disease was observed in the study population. Tooth loss (≥6 missing teeth) was greater (27.9%) in the farming than in fishing population (11.1%). Tooth loss was significantly associated with age, socioeconomic status, dental visiting, alcohol and periodontal disease. In the study population, 50%, 27%, 15% and 9% of tooth loss were attributable to the dental visiting, age, periodontal disease and education respectively. Conclusions: The study showed that the rural populations in India carried significant burden of periodontal disease and tooth loss. The first null hypothesis was retained since the prevalence, extent, and severity of periodontal disease were similar in both the communities. Other hypotheses were supported. The risk indicators of periodontal disease such as plaque accumulation, tobacco and alcohol showed clustering. Tooth loss was higher in the farming than the fishing community. Dental visiting was strongly associated with tooth loss in the models and remained significant after propensity score adjustment. Health behaviours are modifiable factors important in controlling periodontal disease and tooth loss. There is an urgent need for improving oral health in this rural Indian population. The findings from the present study point to the importance of concerted efforts by oral health groups, the Dental Council of India along with other health stakeholders in planning public health programs to improve oral health and reduce oral health inequalities.Thesis (Ph.D.) -- University of Adelaide, School of Dentistry, 201