Prevention and screening

The integration of oral health care providers into strategies to enhance early identification of individuals at risk of developing chronic disease may be a future public health strategy aimed at preventing and controlling the growing chronic disease epidemics. The purpose of disease prevention and control is to identify individuals who have an increased likelihood of developing disease or experiencing increasing disease severity. Successful prevention is predicated on several underlying tenets, the primary one being the need for an integrated approach that incorporates health care professionals across disciplines. The disease should preferably also have well-recognized, modifiable risk factors, and available, simple, safe, and effective screening tools. Furthermore, individuals who could benefit from screening need to be identified and provided access to prevention programs. A new direction for disease prevention embraces identifying and screening for health indicators and social determinants in conjunction with disease risk indicators.

Screening tests are primarily conducted to assess the risk of developing disease among individuals who present with no clinical signs or symptoms of disease. Early identification of individuals at increased disease risk, yet unaware of their increased risk, allows for early entry into the medical system when medical and or behavioral interventions can affect the risk of disease development. Screening can be considered a flagging mechanism to select individuals who may warrant further confirmatory testing. Screening tests are performed to assess the presence or level of well-recognized disease markers or risk factors and are critical components for strategies to prevent and control disease epidemics. Individuals with positive screening tests are referred to the appropriate health care provider for diagnosis or follow-up for disease/risk monitoring. Screening tests can also monitor an individual’s disease progression, and control of individual risk factors once a disease diagnosis is made, or the presence of specific risk factors is confirmed.

Why screen for medical conditions in a dental setting?

Screening for risk of developing disease can alert patients to potential disease risks or health issues of which they are unaware. On average, 65% to 70% of adults visit the dentist in a given year, 10% to 20% of whom have not seen a physician in the preceding year, suggesting a potential role for oral health care providers in public health strategies to prevent the onset of, or control the severity of diseases of important public health significance. Cardiovascular disease (CVD) and diabetes mellitus (DM) are increasingly important public health concerns that meet the fundamental criteria for effective screening. Screening for medical conditions in a dental setting is a novel approach that could be an effective component of a disease prevention/control strategy that integrates health professionals across disciplines. Implementing screening for systemic conditions in a dental setting should be encouraged not only from a public health perspective but also as an approach to provide additional patient information that could affect delivery of oral health care. Recent data suggest a bidirectional relationship between periodontal disease and diabetes, whereby the presence of diabetes associated with poor glucose control is a risk factor for periodontal disease and may even affect the efficacy of periodontal disease treatment, and the presence of periodontal disease may adversely affect glycemic control.

An association between CVD and periodontal disease, independent of common risk factors, has been suggested, although data on a causative relationship are inconclusive. Regardless of the exact nature of the relationship between the presence of oral disease and CVD, data support screening dental patients for well-recognized indicators of increased risk for developing CVD, such as hypertension, obesity, and cholesterolemia.

Why screen for medical conditions in a dental setting?

Screening for risk of developing disease can alert patients to potential disease risks or health issues of which they are unaware. On average, 65% to 70% of adults visit the dentist in a given year, 10% to 20% of whom have not seen a physician in the preceding year, suggesting a potential role for oral health care providers in public health strategies to prevent the onset of, or control the severity of diseases of important public health significance. Cardiovascular disease (CVD) and diabetes mellitus (DM) are increasingly important public health concerns that meet the fundamental criteria for effective screening. Screening for medical conditions in a dental setting is a novel approach that could be an effective component of a disease prevention/control strategy that integrates health professionals across disciplines. Implementing screening for systemic conditions in a dental setting should be encouraged not only from a public health perspective but also as an approach to provide additional patient information that could affect delivery of oral health care. Recent data suggest a bidirectional relationship between periodontal disease and diabetes, whereby the presence of diabetes associated with poor glucose control is a risk factor for periodontal disease and may even affect the efficacy of periodontal disease treatment, and the presence of periodontal disease may adversely affect glycemic control.

An association between CVD and periodontal disease, independent of common risk factors, has been suggested, although data on a causative relationship are inconclusive. Regardless of the exact nature of the relationship between the presence of oral disease and CVD, data support screening dental patients for well-recognized indicators of increased risk for developing CVD, such as hypertension, obesity, and cholesterolemia.

Burden of CVD and DM

Coronary heart disease (CHD), which constitutes 50% of CVD, is the leading cause of death for both men and women in the United States. According to the American Heart Association (AHA), approximately 13 million Americans have symptoms of CHD. As the life expectancy and obesity rate increase in the population, CVD and DM are becoming increasingly more prevalent, with 80 million people recognized as having some type of CVD and 26 million with DM; 90% to 95% are type 2 diabetes. The age-adjusted prevalence of CHD decreased from 6.5% to 6.0% from 2006 to 2010, most likely because of improved treatment and control of CHD risk factors. Between 1988 and 1994 and 1999 and 2006, there was an increase in prediabetes from 29% to 34%. The prevalence of undiagnosed disease is estimated to be 29% to 71% for CVD (depending on the specific risk factor) and 27% to 53% for DM and prediabetes. Associated with the increasing prevalence of these diseases are increasing levels of disability and growing health care expenditures. Recent reports suggest disease prevalence and costs will continue to increase.

Primary and secondary prevention activities aimed at modifying well-recognized risk factors associated with these diseases (eg, high blood pressure, high cholesterol, and overweight/obesity) have resulted in substantial reductions in disease-specific incidence, morbidity, and mortality. According to the US Preventive Services Task Force Guide to Clinical Preventive Services, the goal of primary prevention (eg, vaccine administration and counseling to encourage healthy behavior) is to prevent disease onset, whereas secondary prevention (eg, screening) is meant to identify and treat those with disease risk factors and is focused on early identification of asymptomatic disease. Dietary modifications and increased physical activity are associated with a 35% to 77% reduction in the incidence of hypertension, a 4% to 10% reduction in high cholesterol, an 11% to 15% reduction in incidence of CVD, and a 27% reduction in CVD mortality. Longitudinal studies of lifestyle interventions to prevent DM reported a decrease of 50% in DM incidence during the time of the intervention and a sustained decrease of 41% over a 20-year follow-up period.

Data indicate the beneficial effect of fitness and physical activity on CHD-associated risk factors. Maintaining or improving fitness was shown to significantly reduce the risk of developing CHD risk factors during a 6-year period, whereas supervised exercise significantly reduced levels of existing risk factors, including hemoglobin A1c, blood pressure, high-density lipoprotein, low-density lipoprotein, triglycerides, and body mass index over a 12-month period. No studies have evaluated the impact of oral health care professionals engaging in assisting individuals with lifestyle changes, such as encouraging patients to become more physically active and change unhealthy diets; however, dentists may be reluctant to educate and counsel patients about specific conditions, such as obesity, unless these conditions directly affect a patient’s oral health.

Among the numerous screening tools for CHD-associated events, the well-validated Framingham Risk Score (FRS), which uses demographic and clinical measurements, is among the most widely used in the United States. The FRS estimates the 10-year risk of developing a severe CHD outcome based on demographic, clinical, and laboratory data. The added utility of additional biomarkers, such as C-reactive protein, is moderate at best and not recommended for routine screening for CHD. The AHA’s “Guideline for Assessment of Cardiovascular Disease in Asymptomatic Individuals” suggests that measurement of C-reactive protein may be useful in asymptomatic men younger than 50 years and women younger than 60 years with an intermediate CHD risk. Recently, the use of a simple and effective screening test for type 2 DM, the hemoglobin A1c test (A1c), was endorsed by an expert panel. Subsequently, a global study demonstrated that hemoglobin A1c levels can be used to estimate average blood glucose levels for most patients with DM. In April 2010, the American Diabetes Association recommended the use of the hemoglobin A1c test for screening and diagnosis of DM in routine clinical practice. A community-based study validating the use of the A1c for diagnosis of DM found the baseline levels of hemoglobin A1c in an adult population were significantly associated with newly diagnosed DM and CVD. An 8-year longitudinal study reported that the risk of developing diabetes increased as A1c levels increased from more than 5.0% to 6.0% to 6.4%. Use of the A1c point-of-care test is a significant step forward in the screening and diagnosing for DM, as, before this, the accepted screening test for DM required the determination of fasting plasma blood glucose levels.

Calls for prevention and expanded screening for CVD and DM

Is there a role for oral health care professionals?

In previous studies, we developed and pilot-tested a CHD and DM screening strategy for use in a dental setting to identify asymptomatic individuals who are at increased risk for developing DM- and CHD-associated events. Demographic (age, gender, smoking history) and clinical data (reported history of hypertension, hypercholesterolemia, CHD, heart attack, stroke, angina, medication use for high blood pressure or high cholesterol) were abstracted from National Health and Nutrition Examination Survey (NHANES) 1999-2000 and 2001-2002 surveys. Data on adults 40 to 85 years of age who had not seen a physician in the past 12 months, but had seen a dentist, were used to calculate the FRS for each study subject to determine their 10-year global risk for developing acute CHD events. Among eligible males older than 40 years, 18% had an increased 10-year global risk for a CHD event (>10% risk score), 14% had a moderate, above-average risk score (>10% and <20%), and an additional 4% had a high risk (≥20%). Extrapolating the study algorithm to the 2000 US Census data showed that among males 40 to 85 years old without reported risk factors, who had not seen a physician, but had seen a dentist in the past 12 months, 332,262 had an above-average and 72,625 had a high 10-year CHD risk. Income and medical care are inversely related, suggesting there may be a significant number of low-income people unaware of their increased risk of CHD who could benefit from screening in nontraditional locations, such as dental settings.

We then expanded on our theoretical calculations with the NHANES data to an efficacy study in an inner-city dental school clinic. Calibrated, trained dentists administered a CHD risk screening questionnaire, measured blood pressure, and tested cholesterol, high-density lipoprotein, and hemoglobin A1c using fingerstick blood collected on a convenience sample of New Jersey Dental School adult patients. Eligibility criteria were: 40 years or older; not being told of having any CHD specific risk factors; no reported history of heart attack, stroke, angina, or DM, and no visits to a physician in the past 12 months. Fingerstick blood was used to measure total cholesterol, high-density lipoprotein levels, and A1c levels chairside with validated machines that yield results within 5 to 7 minutes. Clinical measurements and demographic data were used to calculate the FRS. Among the participants, 17% had an increased 10-year CHD risk (FRS >10%); of these, 14.0% (95% confidence interval [CI] = 10.4–17.6) had moderate above-average risk (>10% and <20%), and 2.2% (95% CI= 0.78–5.2) had high risk (≥20%). One-third of males and 5% of females had FRS higher than 10%. A total of 71% had at least one major risk factor of interest. At the time the study was published (2007) the recommended A1c cut point was 7.0%; at that level, only 1 male was found to be at positive for abnormal A1c levels. Using new A1c screen positive cut points set in April 2010 (>5.7%), 21% would have been at increased risk for DM.

Use of dental settings could augment identification of individuals who could benefit from early intervention. A recent preliminary study in Sweden assessed the diagnostic yield of chairside medical screening in a dental setting. In this setting of universal health care, the heart score was used, which identifies individuals who are at an increased risk of dying from a CHD event within 10 years. Among the 6% who were identified as being at increased risk of dying from a CHD event, 50% were subsequently given medical intervention following evaluation by a physician. These data support earlier work showing the efficacy of chairside medical screening in a dental setting and should be corroborated. Another study in an inner city dental school clinic also supports an important role for oral health care professionals in early disease identification. Unrecognized diabetes in dental patients was successfully identified using 2 dental parameters (number of missing teeth [at least 4] and percentage of teeth with deep [≥5 mm] periodontal pockets [at least 26%]); the presence of either dental parameter had a sensitivity of 73% and adding of A1c measurements improved the sensitivity to 92% compared with fasting glucose. Use of A1c alone showed as sensitivity of 75%.

Given the existence of simple, safe, effective, and relatively inexpensive screening methods, the availability of effective means to identity at-risk individuals and the documented benefit of primary and secondary prevention, chairside screening for medical conditions should be an integral component of dental practice. How do we encourage this practice among dentists? In the behavioral research literature, the theories of planned behavior and reasoned action are the most widely researched principles of behavior change. Fundamental to these theories is the premise that intentions predict behaviors. Studies among a variety of health care providers, including physicians, nurses, and mental health providers, show that attitudes are among the strongest predictors of intentions. Understanding the attitudes and the perceived barriers to this strategy is essential for success.

Data from a national survey among practicing general dentists showed that 90% of the respondents felt it was important for dentists to screen for medical conditions, and most were willing to conduct chairside screening and discuss the results immediately with their patients, and were willing to refer patients to a physician for follow-up care. A national random sample of US general dentists was surveyed by mail with an anonymous 5-point Likert scale (1 = very important/willing; 5 = very unimportant/unwilling) questionnaire. Of 1945 respondents, a response rate 28%, there was a margin of error of less than 3%. Among the respondents (82% male; 86% white; 60% 40–60 years old; 85% practiced for >10 years), most felt it was important for dentists to screen for hypertension (86%), CVD (77%), DM (77%), human immunodeficiency virus (72%), and hepatitis C (69%); and were willing to refer patients to physicians (96%), collect saliva samples (88%), conduct screening that yields immediate results (83%), and collect fingerstick blood (56%). Based on comparisons of calculated mean ranks, insurance coverage was ranked the least important potential barrier, including time, cost, liability, or patient willingness. Surprisingly, although insurance coverage was important, it was not ranked the most important factor by the practitioners when considering incorporating chairside screening into their practice. A question about potential barriers for incorporating chairside screening into their practice revealed that patient willingness was ranked the most important consideration and insurance coverage was the least important. Other studies conducted since have reported that most dentists feel it is important and they are willing to conduct screening for medical conditions that patients are unaware of or to address medical conditions such as obesity. A study from New Zealand reported that almost all general dentists participated in some phase of disease management of patients with DM, although most were less willing to participate in hands-on activities. Preliminary data among a national sample of practicing primary care physicians show that most respondents felt it was important for dentists to screen for CVD, hypertension, and DM and that they would accept patient referrals based on medical screenings conducted in the dental setting.

An equally important question is how do patients feel about screening for medical conditions in a dental setting. Data from a survey among adult patients attending a university-based dental clinic or seen by community dental practitioners indicate that most patients felt chairside medical screening in a dental setting is important and they were willing to participate in such activity. Confidentiality was their most important concern and not being done by a physician was the least important. Most felt it was important for dentists to conduct medical screening (94%); and were willing to have dentists conduct screening for CVD (81%), hypertension (90%), and DM (83%). Most were also willing to have dentists conduct screening that yields immediate results (91%), discuss results during the visit (88%), receive a referral to a physician (89%), provide saliva specimens (88%), provide fingerstick blood (75%), and pay $10 to $20 (69%). Most felt their opinion of the dentist would improve for competence (76%), compassion (76%), knowledge (80%), and professionalism (80%), suggesting that patients felt screening was beneficial.

A recent review found that repeatedly providing CHD risk information to patients increased a patient’s perceived risk and intent to start therapy. Another essential element for an effective strategy to control the global epidemic of CHD and DM is an effective mechanism to refer patients for follow-up medical care and to facilitate referral completion. These elements, along with identifying mechanisms for practitioner reimbursement, require further consideration and input from all stakeholders to continue moving this strategy forward.