Bulpitt and Fletcher's Specific Questionnaire for Quality of Life Assessment of hypertensive patients INSTRUMENTO DE AVALIAÇÃO DA QUALIDADE DE VIDA PARA HIPERTENSOS DE BULPITT E FLETCHER INSTRUMENTO DE EVALUACIÓN DE LA CALIDAD DE VIDA PARA HIPERTENSOS DE BULPITT Y FLETCHER

This study translated and validated Bulpitt and Fletcher's Specific Questionnaire for Quality of Life Assessment of hypertensive patients. The translation and the backtranslation were performed by four English teachers, and the final version was submitted to a board of referees. Questions with a Content Validity Index lower than 80% were modified and re-evaluated. The questionnaire was applied in 110 hypertensive outpatients (52 ± 8 years old, 65 % female, blood pressure 128 ± 17 / 75 ± 13 mmHg), which also answered the SF-36, and also in 20 normotensive people, whose characteristics were similar to those of the hypertensive subjects. The domains of SF-36 and Bulpitt and Fletcher's instrument correlated to each other (p < 0.05), except for the social aspects (r = 0.07, p = 0.04) and the general state of health (r = 0.04, p = 0.61). Hypertensive patients showed more positive responses to the symptoms (40%) than the normotensives (15%). The instrument was validated and is now ready to be used in our midst.


INTRODUCTION
Hipertension is a highly-prevalent disease in our midst. The V Brazilian Guidelines in Arterial Hypertension show that population studies performed in some Brazilian cities show that the prevalence of the disease ranges from 22.3% to 43.9% (1) . Hypertension is one of the main factors of risk for cardiovascular diseases and has high costs, not only in the healthcare area, but also in the socioeconomic sphere. These costs usually originate in complications that include cerebrovascular diseases, coronary diseases, heart failure, chronic kidney failure and vascular disease of the extremities. In Brazil, cardiovascular diseases are the foremost cause of morbimortality, as 27.4% of the deaths in 2003 were due to those diseases, with strokes being the main cause of death in all regions of the country, victimizing mainly women (1) . In addition to being responsible for 40% of the deaths due to strokes, it also accounts for 25% of those caused by coronary diseases (2) .
Hypertension is a chronic disease that requires drug and non-drug treatment for life, and its chronicity may interfere directly in several spheres of the patients' life. The hypertensive patient's self-esteem may be threatened due to the possibility of aggravations, and, consequently, the emotional sphere as well, with the onset of negative emotions such as depression and anxiety (1) . In addition to this psychological aspect, physical changes may emerge due to side effects of hypertensive drugs and cardiovascular changes caused by hypertension itself.
Therefore, the quality of life of patients undergoing treatment, either drug-based or not, may be affected by the side effects of the drugs, the diseases that may be associated to the hypertension, the necessity of changes in the lifestyle and also by the diagnosis of the disease, which apparently causes the loss of the body silence and the presence of the disease as a factor of death, thus changing quality of life (1) .
An important consideration regarding the monitoring of hypertensive patients is that the method used to reduce their blood pressure should not interfere in their quality of life (5) . Due to this perception, in the past decades, the interest for evaluating the hypertensive patients' quality of life increased significantly.

QUALITY OF LIFE AND HYPERTENSION
One of the greatest challenges in the diagnosis and control of hypertension is related to knowing the impact of the disease and its treatment on the patient's life. The asymptomatic course of the disease, until it is discovered or until the targeted organs are damaged are important factors that make this aspect even more difficult.
Studies have shown that the knowledge of a hypertension diagnostic reflects on the report of symptoms, on absenteeism at the workplace and on quality of life (1)(2)(3)(4)(5)(6)(7)(8)(9)(10) . A study performed in the 1970s shows that the lack of balance, dizziness and nocturia were consequences of hypertension, and that they could significantly deteriorate the patient's quality of life (5) . Hypertensive patients have their quality of life significantly reduced when compared to normotensive people, especially women, with more damage to the target organs, higher heart rate and weight excess (2) . Therefore, evaluating the quality of life in hypertensive people became an important part in the proposal of treatment.
The instruments used to evaluate the hypertensive patient's quality of life must be sensitive to the evaluation of the adverse events of each anti-hypertensive drug, among other topics. These authors suggest that the dimensions chosen in studies about quality of life should reflect the potential of adverse events of the treatment, as well as the deficit in the performance at work, problems with sexual functions and mood swings (1) .

BULPITT AND FLETCHER'S SPECIFIC QUESTIONNAIRE FOR HEALTH-RELATED QUALITY OF LIFE ASSESSMENT OF HYPERTENSIVE PATIENTS
Bulpitt and Fletcher's Specific Questionnaire for Health-Related Quality of Life assessment of hypertensive patients (1) was designed in order to be used in studies lasting up to one year. As it focuses on the evaluation of the impact of hypertension, itself an asymptomatic disease, it only detects psychological and mood alterations due to the diagnostic and adverse effects of the treatment in hypertensive patients undergoing outpatient treatment. This questionnaire does not allow for the detection of long-term changes due to conditions that may affect the independence of the individuals, such as strokes. In these cases, the use of questionnaires that evaluate the health profile and describe the limitations in the lifestyle due to the disease, such as the Nottingham Health Profile (NHP), is indicated.
Bullpit and Fletcher's questionnaire (attached) is selfapplicable, and deals with aspects of physical and psychological well-being and the patient's perception of the antihypertensive treatment on their lifestyle. It has questions regarding the clinical situations, the side effects of the treatment and the social, professional, emotional and sexual aspects that are possibly related to the disease or the treatment. It is straightforward, clear, simple, and, especially, it focuses on the main aspects involved with hypertension. The questions were elaborated so as to be answered with yes or no, and there is the option of an open-ended an-One of the greatest challenges in the diagnosis and control of hypertension is related to knowing the impact of the disease and its treatment on the patient's life. · 0.975: none of the aforementioned situations, how ever, the patient has less than 30% of posi tive answers in questions 1 to 30 in the questionnaire; · 1.000: none of the aforementioned situations and no positive answer in questions 1 to 30.
Open-ended questions have only a descriptive, complementary function.

VALIDATING BULPITT AND FLETCHER'S QUALITY OF LIFE ASSESSMENT INSTRUMENT FOR HYPERTENSIVE PATIENTS
The questionnaire was translated to Portuguese by two English teachers, who were native to the country of origin of the instrument. This first version in Portuguese was backtranslated into English by two Brazilian teachers of English, who had not taken part in the previous stage. Later, the original instrument and the translated versions were compared: the divergences were analyzed by the group, rewritten when necessary, and finally a consensus was reached, which yielded the final version of the instrument.
The final version of the instrument was submitted to a board of referees composed by three physicians and three nurses, all of them bilingual and aware of the disease in question, as well as the goals of the questionnaire and the concepts being analyzed. This process aimed to guaranteeing the reproductibility of the instrument in another language. The board of referees was allowed to suggest the replication of instructions on how to fill the form in order to minimize errors in its comprehension, as well as suggesting changes or the elimination of items that were considered irrelevant, inadequate and/or ambiguous, and present others that are more culturally adequate and understandable for the general population, if that were the case.
After the analysis, the changes suggested by the referees were implemented, with the items that were agreed upon by at least 80% of the evaluators. To obtain the index of agreement regarding the conceptual equivalence, the evaluations of each referee were compared with the evaluations of all the others, with the CVI being calculated for each pair (referee A × referee B; referee A × referee C; referee B × referee C; and so on). The CVI was calculated for each item, which indicated the percentage of answers with satisfactory translations among the referees, on an itemby-item basis. This index was useful in the identification of items that needed to be changed.

CVI = number of items evaluated as equivalent by two referees
Total number of items of the scale CVI = Content Validation Index Out of the 46 questions that comprise Bulpitt and Fletcher's Quality of Life assessment instrument, only questions 1, 3, 21, 23 and 31 needed to be modified due to low CVI. These questions were not agreed upon by 80% of the referees in some of their equivalences, and, as such, needed to be changed in order to become equivalent.
Afterwards, the instrument was pre-tested, which is the stage of the translation process where the equivalence between the original and the final version of the instrument, analyzing the comprehension of its items by the target population. For that, the instrument was applied on a group of 10 patients. A not applicable answer was added to each question of the instrument, with the purpose of identifying which items could present cultural incompatibilities, which were not usual or even nor understood by our population. Questions with more than 10% of not applicable answers were carefully re-evaluated and rewritten, in order to maintain the properties and structure of the question. This stage was performed with 10 hypertensive patients with characteristics that were similar to those patients evaluated in the criterion validity stage.
The modified instrument was re-applied on a new group of 10 patients. The instructions, as well as each of the items, were discussed with the patients regarding its clarity and comprehension, which resulted in the instrument presented in the appendix.
For the next validation stage, which corresponded to the estimates of criterion validity, 110 hypertensive people undergoing outpatient treatment were studied, aged 52 ± 8 years old, female (65%), white (60%), with full elementary education (63%), married (68%), with a body mass index of 30 ± 4 Kg/m2 and average blood pressure 128 ± 17 / 75 ± 13 mmHg. This stage refers to the degree of correlation of the scores of an instrument to a reliable external criterion, designated as the gold standard. The Medical Outcomes Study 36-Item Short-Form Health Survey -SF-36 -was used as the gold standard for this analysis. In spite of being a generic questionnaire, it has dimensions that could be correlated with the specific questionnaire about hypertension, in addition to being an instrument that has been used in several studies, showing good measurement properties such as reproductibility, validity and susceptibility to alterations. The SF-36 has also been used by other investigators in several diseases, including hypertension. It was translated and validated for the Portuguese language in 1997 (1) . Therefore, the instrument undergoing evaluation had its components grouped according to the dimensions that existed in the SF-36 by the Brazilian authors (social aspects, general state of health, physical aspects, vitality, functional capacity, mental health, emotional aspects and pain). The comparison between both instruments revealed a significant statistical correlation among all domains, with two exceptions: social aspects and general state of health (Table 1). Vitality was the item with the lowest score, both in SF-36 (56 ± 22) and in Bulpitt and Fletcher's specific questionnaire (1.5 ± 0.5). In both questionnaires, functional capacity (SF-36 = 75 ± 22 and Bulpitt = 6 ± 1) and social aspects (SF-36 = 77 ± 30 e Bulpitt = 5 ± 1) were the highestscoring domains (Table 1).   In the social aspects and general state of health, the correlation coefficients were not significant (  Figure 2 shows that the outline of Bulpitt and Fletcher's questionnaire is very similar to the SF-36, with the exception of the social aspects and the general state of health domains, which did not have a good correlation, and the mental health domain, which had an inverse correlation, Figura 2 -Percentage of "Yes" and "No" answers in the hypertensive and normotensive groups. as described before. These aspects are probably due to the characteristics of the evaluated instrument, whose focus is not the isolated evaluation of these domains, focusing instead on the adverse effects of the treatment. The next stage consisted of the application of the instrument to a group of normotensive people to verify the capacity of discrimination among groups expected to have differences among each other. For this validation, a group of normotensive people (blood pressure < 140/90 mm Hg) was correlated with a group of hypertensive patients (blood pressure ≥ 140/90 mm Hg, with or without drug treatment, or blood pressure < 140/90 mm Hg with drug treatment), previously evaluated. Figure 2 shows that the number of yes answers to changes or symptoms mentioned in the instrument used with the normotensive group was significant lower (15%) than the same answer in the hypertensive group (40%). These data suggest that the hypertensive group had a higher deficit in quality of life when compared with the normotensive group. The difference (p < 0.05, chi-square test) detected by the instrument shows its ability of discriminating among different groups.

CONCLUSION
Bulpitt and Fletcher's questionnaire is the first specific instrument about quality of life for hypertensive patients, in Brazil, that has undergone the whole process of translation and transcultural adaptation proposed by literature. As its validity is thus proven for the anti-hypertensive treatment, it can be used in the clinical practice and investigation.