Non-communicable diseases (NCDs) are chronic diseases that are not directly transmissible from one person to another and depict the true meaning of the word insidious as it results in over 71% of all deaths globally and often remain undetected until the condition has reached a nearly fatal stage especially in low and middle income countries. (1) Cardiovascular diseases (like heart attacks and stroke), cancers, chronic respiratory diseases and diabetes are the major NCDs.(1) Dementias are also on the rise with Deaths due to Dementias becoming the 5th leading cause of global deaths.(2)In 2016, Ischemic heart disease and stroke were recorded as the world’s biggest killers, and these conditions continue to maintain their lead role in global deaths. COPD, Cancers, Diabetes are not far behind the Cardiovascular conditions in being the major causes of deaths worldwide.(2) Tobacco use, physical inactivity, unhealthy diet and the harmful use of alcohol are modifiable risk factors that can lead to an increase in the risk of NCDs. Elevated blood pressure, overweight/obesity, hyperglycaemia (high blood glucose levels) and hyperlipidaemia (high levels of fat in the blood) are the metabolic risk factors that can bring about metabolic changes that in turn contribute towards an increase in the risk for NCDS.(3) Stress and social determinants of health such as a person’s economic and social conditions can also increase the risk for NCDs.(4) The burden of NCDs on National economies is tremendous with an estimated loss of 9 billion international dollars in national income in India in 2005 due to death or inability to work due to heart disease, stroke and diabetes.(5)

Periodontitis, as an inflammatory, non-communicable disease with a multifactorial aetiology is an extremely prevalent condition. More than 10% of the adult population worldwide are affected by severe periodontitis and the condition may even be more prevalent than cardiovascular diseases. Periodontal disease is estimated to be the 11th most prevalent disease globally with an overall prevalence of 7.4% and around 538 million people are affected.(6) According to the Global Burden of Disease Study, periodontal diseases are responsible for 3.5 million years lived with disability. (3)Periodontitis also compromises speech, reduces quality of life, and is an escalating burden to the healthcare economy(6) and it shares numerous risk factors like smoking, obesity, nutrition, low socioeconomic status and stress with other Non-Communicable Diseases (NCDs) like Diabetes, Cancer, Cardiovascular and Cerebrovascular diseases.(7)(8)(9)(10) Patients with periodontitis are at risk of multiple tooth loss, edentulism and masticatory dysfunction and this in turn can affect their food habits and level of nutrient rich food intake. The quality of life and self-esteem of an individual also will be affected in addition to imposing huge socio-economic impact and healthcare costs. (6)(11)The global cost of lost productivity from severe periodontitis alone has been estimated to be 54 billion USD/year. The total economic impact of periodontal diseases has been estimated at 440 billion USD (direct and indirect costs) in 2010. In the UK, managing periodontal disease cost the National Health Service over £2.8 billion in 2017.(12)

Clustering of risk factors has been observed especially in relation to the NCDs. (13) The co-occurrence of several characteristics in one individual is termed as clustering.(13) The concept of clustering of risk factors revolves around multiple factors. For example, socioeconomic position in childhood has strong effects on distributions of risk factors in adult life leading to the hypothesis that socioeconomic position might be associated with clustering of risk factors for Cardiovascular diseases, Diabetes mellitus and other NCDs. Clustering occurs when the observed prevalence of a combination of factors exceeds the expected prevalence for this combination.(14) Behavioural and demographic characteristics that predisposes towards major chronic diseases frequently cluster in the same individuals. Drinking and smoking; smoking and consumption of food high in fats and sugars and low in fibre, polyunsaturated fatty acids, fruit and nutrient rich foods containing Vit A, C and E; Unhealthy diet, sedentary lifestyle and deleterious life habits are often seen grouped together in people. (14)(15)

Interventions addressing multiple behavioural, environmental and other risk factors have greater impact than those aimed at isolated behaviors.(16) The concept of Common Risk Factor Approach (CRFA) is based on the scientific concept that if disease A is caused by C and disease B is caused by C, then reduction of C should facilitate the reduction of both A and B, that is, controlling a small number of risk factors can have tremendous impact on controlling a large number of chronic conditions. Impetus for Common Risk Factor Approach (CRFA) for tackling the common risk factors associated with the NCDs has been cresting for a while in the world of healthcare. (17) Several programs have been initiated in which CRFA has been implemented to achieve better general health.(18)(19)A few advocacy initiatives focusing on CRFA in relation to oral health and general health have attempted to forge the relation between NCDs and oral health through the commonality of risk factors and thus initiate an active reduction of the conditions through the CRFA.(20)(21)(22)(23)

Public health approach for prevention of periodontal disease as a component of an integrated approach with systemic health, particularly with non-communicable disease prevention activities, focusing on common risk factors, can pave the way towards better overall health with a concomitant reduction in health care costs. Consequently, the model of a common risk factor approach (CRFA) has been conceptualized for the public health approach to prevent periodontal disease.

The limited availability of numerical data on the influence of the various risk factors on the NCDs and on periodontal disease makes it difficult to bring out a fool-proof plan to create a convincing argument favoring Common Risk Factor Approach. This research has been designed to overcome the deficiency in literature in relation to the quantification of the common risk factors between periodontal disease and NCDs. Policies are based on evidence and evidence is based on statistics. The quantification of percentage overlap of risk factors between NCDs and Periodontal disease would result in the development of advocacy initiatives which would help in reduction of risk factors associated with periodontal disease and NCDs.The capacity building demonstration model of Integration of Periodontal health (oral health) in primary health care will be aimed to facilitate the development of avenues for effective integration of medical and dental care administration.This research has been planned to answer the question on what is the attributable risk for factors that are common between periodontal disease and other major non-communicable diseases (Diabetes Mellitus type 2, Cardiovascular disease) in adults?

This study is based on the rationale that periodontal disease shares a wide range of risk factors and risk indicators such as tobacco use and alcohol, dietary factors, stress, plaque microbiota, oral hygiene, social determinants of health(SDH) with other systemic diseases conditions particularly the other major NCDs such as cardiovascular disease, chronic respiratory disease, cancer, and diabetes. Quantification of these risk factors would enable the implementation of Common Risk Factor Approach for the integration of periodontal disease prevention into public health approaches for NCD prevention and control activities