Tarek L. Al-Khateeb BDS., MDS., PhD. Mohammed A. Mahmoud BDS., MSc, PhD.
King Abdul-Aziz University , PO  Box  51372,   Jeddah  21543.   Saudi  Arabia

The objective of the present study was to determine the frequency and distribution of hypertension in an adult population of dental patients (>18 years). The study was conducted on 1320 patients (624 males and 696 females). The frequency of hypertension was determined through history taking, and by measuring the blood pressure values of every patient. Blood pressure values and hypertension frequencies were analyzed as related to the age and sex of the total population studied. The results showed a hypertension frequency of 26.4%. Males showed more frequent hypertension (30.8%) compared to females (22.4%). Of the recognized hypertensive patients, 59.2% were either unaware or uncontrolled     hypertensive     patients. Blood pressure     values and  frequency of hypertension increased with age. In older individuals (55 years or more), hypertension frequency markedly increased to 58.6% in males, and to 60.6% in females, The findings were compared to those reported in other populations, and the dental implications were discussed.
 

The potential risk associated with dental treatment of patients with hypertension has been well documented. Variable increases and fluctuations in blood pressure values, as well as adverse hemodynamic and cardiovascular changes have been recognized during dental treatment of hypertensive patients. " In addition, the identified adverse metabolic effects and interactions of antihypertensive medications represent another potential risk further complicating dental treatment. Despite the identified risk, evaluation of dental patients regarding their blood pressure status is not always as thorough as it should be; and adverse reactions have been reported as a result of dental treatments conducted without being aware of the potential medical risks. '

Recent data have shown increased frequencies of hypertension among those seeking dental treatment. Moreover, it has been estimated that over 50% of hypertensive patients are either inadequately controlled or totally unaware of their blood pressure status. This unawareness was reported in a dental population, as well as in a general population. These recognized high frequencies of hypertensive patients, and the high percentage of unaware and uncontrolled cases represent a dental management challenge that needs to be further addressed. More studies need to be conducted on the profile of hypertension in other dental populations; and, the role of the dentists in the identification and management of hypertensive patients needs to be further emphasized.

The objective of the present study was to determine the frequency and distribution of hypertension in an adult population of dental patients among the Faculty of Dentistry, King Abdul-Aziz University.

A total of 1,320 adult patients (>18 years of age) were randomly selected to participate in the present study. The patients were selected from those who attended the screening clinic, Faculty of Dentistry, King Abdul-Aziz University, between 1995 and 1996. The patients' age ranged between 18 and 76 years, and the average age was 37.2 ± 13.9 years. These were 47.3% male (mean age 38.6± 14.4 years), and 52.7% female patients (mean age 36± 13.6 years).

The blood pressure of every patient was evaluated by two methods. First, by responses on direct questioning regarding previous blood pressure measurements, previous diagnosis of hypertension, and current intake of antihypertensive medications. Second, by measuring the blood pressure, applying the auscultation method.

Blood pressure measurements were performed by one and the same examiner. For every patient, blood pressure was taken twice. One measurement was taken at the beginning of the screening session, after the patient was seated comfortably for five minutes; the other measurement was taken at the end of the same screening session. The lower of the two blood pressure measurements was recorded as the patient's true blood pressure to avoid over-estimation of hypertension frequency in the population studied. A patient was categorized as hypertensive based on either a positive history of diagnosed hypertension, or a measured blood pressure value - 140 mm Hg Systolic, and = 90 mm Hg, Diastolic, or = 140 / 90 mm Hg- Patients were divided into five age groups (Table 1). Descriptive statistics were used to summarize the collected data; blood pressure values and hypertension frequencies were analyzed as related to the age and sex of the population studied.

The prevalence of hypertension in the studied population of dental patients was 26.4%. The frequency of hypertension in males (30.8%) was greater than that in females (22.4%). Of the recognized hypertensive patients, 259 (74.4%) gave a positive history of previously diagnosed hypertension, and 89 (25.6%) were unaware of their blood pressure status, but their measured blood pressure values were = 140 mm Hg systolic, = 90 mm Hg diastolic, or = 140/90 mm Hg. Patients with previously diagnosed hypertension were all on antihypertensive medications but with variable compliances to medication. Of those patients, 117 (45.2%) were inadequately controlled based on hypertension threshold >. 140/90 mm Hg, >_ 140 mm Hg Systolic, or >_ 90 mm Hg diastolic.

Table I shows the mean systolic and diastolic blood pressure values, as well as the frequencies of hypertension in different age groups.
The relationships of systolic values, diastolic values, and hypertension frequencies to the age and sex of the population studied are shown in Fig. (1) to Fig. (3). Systolic and diastolic blood pressure values, as well as hypertension frequencies increased with age. A dramatic increase in the frequency of hypertension was noted in older age groups (groups IV and V, Table 1).

In younger age groups (< 55 years), males showed higher systolic and diastolic pressure values, and more frequent hypertension compared to females. In older patients (55 years or more), however, systolic and diastolic blood pressure values in females were closer to those in males; and the frequency of hypertension in female, slightly exceeded that in male patient; (Figs. 1 - 3).

The potential risk associated with dental treatment of hypertensive patients has been largely related to the adverse hemodynamic and cardiovascular changes recognized during stressful dental procedures.³'⁴'² On the other hand, significant blood pressure increases and variable fluctuations have been also recognized in association with non- stressful dental procedures, suggesting a potential risk regardless of the dental procedure.¹³'¹⁵ The need for a routine screening for hypertension has been stressed in order to prevent unexpected complications and systemic exacerbations during dental treatment.¹³'⁴

In the present study, screening of an adult dental population revealed a hypertension frequency of 26.4%. This recognized frequency is comparable to those recently recognized in other dental populations (24%, 28%),⁸⁹ further supporting an increased prevalence of hypertension among dental patients. Over the last two decades, advances in diagnosing and treating hypertension have resulted in a major decline in cardiovascular and stroke mortalities and enabled hypertensive patients to live longer and more productive lives."'⁶ This might have changed the assembly of dental populations to include higher percentage of those patients with hypertension, hence, the recognized high frequencies.

Collectively, unaware and un- controlled patients represented 59.2% of the total hypertensive patients recognized in the present study. This is consistent with the recent data indicating that over 50% of the hypertensive patients in general population, as well as in dental populations⁸ are either un- aware or uncontrolled. Accord- ingly, inspite of the increased pub- lic awareness of hypertension, and the rapidly growing array of anti- hypertensive medications, unaware and uncontrolled cases still repre- sent major proportions of hyper- tensive patients. This observation further emphasizes that dentists should be aware of the blood pres- sure status of theirpatients in order to avoid the complications and interactions anticipated during treatment of asymptomatic or un- controlled cases.

Data in the literature indicates a higher prevalence of hypertension in males compared to females, but, with comparable hypertension fre- quencies between males and fe- males in older age groups.'⁷ The results of this study are consistent with these data. In younger age groups (<45), males showed higher blood pressure values and more frequent hypertension than fe- males, which contributed to the higher overall hypertension fre- quency in males compared to fe- males in the total patients studied. In older patients, however, blood pressure values of females were closer to those of males, and the frequency of hypertension in fe- males slightly exceeded that in males.

Both blood pressure values, and hypertension frequency increased with age. In older patients (55 years or more), the highest blood pressure values were recognized, and the frequency of hypertension markedly increased to 59.7%. This is consistent with the studies identi- fying hypertension as the most common systemic disease in elderly dental patients, ¹⁸ and in older populations in general.¹⁹ Thus, older individuals are at a markedly greater risk of dental treatment. Efforts towards evaluation of their blood pressure are even more im- portant than in younger individu- als.

In conclusion, the results of the present study indicate that an in- creasing number of hypertensive patients are seeking dental treat- ment. The recognized higher fre- quency of hypertension in older patients, and the high percents of unaware and uncontrolled cases

suggest an increased risk. Perform- ing dental procedures on those pa- tients could bring about serious complications, and acute exacerba- tions of their systemic conditions. Consequently, it is the responsibil- ity of the dentist to identify those patients at risk, evaluate the associ- ated risk, and be aware of the side effects and interactions of the rele- vant antihypertensive medications. Furthermore, it is essential that the dentist should be prepared to apply preventive and stress reduction measures, as well as to manage unexpected hypertensive emergen- cies.