EDITORIALS
The hypertensive patient: 4. Stepped-care therapy In their recommendations on the treatment of hypertension the Canadian hypertension task forces and committees* recognize four maxims. First, nearly all of the care of hypertension will be provided in primarycare settings, by either general practitioners or specially trained nurses. Second, the treatment regimens will involve antihypertensive drugs; although exciting progress is being made in determining the potential usefulness of nondrug strategies, they are not considered feasible at present. Third, because the execution of these recommendations may result in increasing drug ingestion by Canadians, we have sought "tried-andtrue" regimens whose efficacy and safety have been established by both large-scale randomized clinical trials and long-standing use. Fourth, we have attempted to keep these regimens simple in an effort to minimize cost, confusion and noncompliance. Stepped care is a regimen in which a single, mild antihypertensive drug is prescribed initially, then more powerful drugs are prescribed, if necessary, in a straightforward manner until a predetermined "goal" blood pressure is achieved. Stepped care has also been adopted by a number of advisory groups and health professional organizations elsewhere.1'2 The objective of stepped care is to maintain the level of diastolic blood pressure in the goal range by using the most efficacious therapeutic regimen for each patient. Hence, the treatment effect is maximized while undesirable and unpleasant side effects, the complexity of the treatment regimen, and the number and potency of agents used are minimized. The Canadian task forces recommend as a goal the achievement and maintenance of diastolic blood pressures less than 90 mm Hg or a decrease of 10 mm Hg, whichever is lower. The first step consists of administering a thiazide or related diuretic, usually at half the full daily dose, and then progressing in one step to the full dose, allowing a minimum of 2 weeks or a maximum of 6 weeks at each dose. In this way one can assess *Details pertaining to the hypertension task forces and committees may be found in the first of this series of articles on hypertension, published June 9, 1979. The entire series is appearing in consecutive issues of the Journal.
the efficacy of the drug for up to 12 weeks before concluding that the first step is not adequately effective. In the first step clinicians are advised to use the drug with which they are most familiar. A thiazide or related diuretic was used as the firststep drug for the following reasons: * A substantial proportion of less severely hypertensive patients (diastolic blood pressure 90 to 120 mm Hg) are satisfactorily controlled by a thiazide diuretic alone. Thus, the patient may have to take only one tablet a day. * Thiazide and related diuretics are generally mild antihypertensive agents that have flat dose-response curves, such that dosage is not critical and response tends to be stable. * Side effects associated with thiazide-type agents are relatively mild and uncommon. * Should one or more additional drugs be required, their effect on decreasing the blood pressure tends to be at least additive to, and may be potentiated by, that of the diuretic; the blood pressure goal may be achieved at doses below those associated with unacceptable side effects. * Thiazide and related diuretics have been available for several years, are well known and widely used by primary-care clinicians, and have been the backbone of active therapy in randomized trials demonstrating the benefits of antihypertensive drug treatment. All thiazides are basically equipotent and have a similar spectrum of side effects - hypokalemia and increased risk of muscle weakness; increased serum uric acid concentration and increased risk of symptomatic gout; decreased glucose tolerance and increased risk of diabetes mellitus; raised blood urea nitrogen concentration; photosensitivity; increased serum calcium concentration; occasional gastrointestinal irritation; and, rarely, blood dyscrasias or pancreatitis. Hypokalemia is an uncommon side effect of treatment with thiazides, and potassium supplementation is seldom required, especially if the dietary potassium intake is increased. However, if a patient is also receiving digitalis, the administration of potassium supplements or the addition of a potassium-sparing diuretic (spironolactone or triamterene) is mandatory. Should potassium depletion (serum potassium concenCMA JOURNAL/JULY 21, 1979/VOL. 121
145
tration 3.0 mmol/l or less) occur a potassium-sparing is added as step 3. Hydralazine is a direct vasodilator diuretic may be added, in which case potassium supple- and may therefore reflexly increase cardiac work. It ments should be discontinued and a close watch kept should therefore be used with caution in persons with on the serum potassium concentration. Again, clini- ar.gina or congestive heart failure. Other side effects cians are advised to use drugs with which they are include headaches, insomnia and the occurrence of a familiar. "lupus-like" syndrome, which rarely occurs when doses If the therapeutic goal is not achieved with full-dose less than 300 mg/d are given. diuretic therapy alone, an assessment of the possible The combination of a diuretic, propranolol and causes of failure should be made before proceeding hydralazine has much to recommend it from both to the second step. The most common causes of failure theoretical and practical points of view, combining at the first step include: (a) poor compliance with the as it does a peripheral vasodilator and a /3-blocker prescribed regimen; (b) the patient's use of competing with significant direct cardiac action to reduce cardiac drugs (e.g., over-the-counter cold remedies) without output. The associated diuretic tends to reduce the the clinician's knowledge; (c) excessive salt intake; or required doses of the other drugs, and controls their (d) an intrinsic disease process whose control is beyond tendency toward fluid retention. the capability of diuretic therapy alone. If the first If the three steps do not control the blood pressure three of these factors can be excluded, another drug satisfactorily, the clinician must consider whether a should be added to the therapeutic regimen. further search for secondary hypertension is warranted. An adrenergic blocking agent - propranolol, a Furthermore, therapy should be individualized and a rauwolfia agent or methyldopa - is used in the consultation considered. Recommendations may include second step. There is no absolute preference among the administration of established drugs such as guanethese drugs, and the choice should be governed by thidine or newer drugs such as clonidine. Seldom would the drug's known mechanisms of action, potency and one of these drugs simply be added to the previous side effects, and the clinician's skill and experience three steps. However, the step 1 diuretic would usually with these drugs. Prime consideration must also be be continued. given to patient convenience, including the cost of What about "stepping down"? Fundamental to the drug and the frequency of administration. Propra- stepped-care therapy is the periodic reassessment of nolol can be taken twice a day and the rauwolfia the patient's blood pressure and the appropriate adagents once a day. Methyldopa is usually given four justment of therapy by "stepping" the regimen either times a day, but recent evidence suggests that it may "up.. or "down... With few exceptions, once the need be taken less frequently.3 The frequency of administra- for therapy has been established it must be life-long. tion may become paramount in determining adherence However, it often may be possible to "step down" the to the treatment program. drug therapy, and this should be done whenever it is At the time this report was in preparation, the use possible to do so without compromising control. of rauwolfia agents was decreasing, and insufficient Follow-up must therefore be regular and systematic, experience with the cardioselective /3-blocking agents the interval between visits usually being 2 months and had accumulated to permit a definitive recommenda- seldom more than 4 months once control is stable. tion. In asymptomatic patients in whom hypertension is The principle of the stepped-care approach should well controlled and stable, long-term follow-up can be followed conscientiously, beginning with the small- be effectively carried out by specially trained and apest dose, allowing enough time for the drug to have propriately supervised nurses. The value of providing its full effect, and then increasing to the next level stepped care in nontraditional settings (e.g., the workuntil an adequate decrease in blood pressure is site) should be determined. achieved. This will promote optimum action with minThe task forces and committees have made the folimum intake and side effects. Of course, a thorough lowing recommendations pertaining to stepped-care knowledge of the side effects of these drugs (Table I) therapy. is a prerequisite for their use. * A stepped-care antihypertensive drug regimen When hypertension is not controlled at the end of is recommended in which a single mild antihypertenstep 2 and poor compliance is not a factor, hydralazine sive drug (a thiazide) is initially prescribed, followed by more powerful drugs if necessary (propranolol, rauwolfias or methyldopa in step 2 and hydralazine Table l-.$lde effects of drugs used In step 2 in step 3), in a straightforward, stepwise manner until a predetermined "goal" blood pressure is achieved. Generic name Side effects * The appropriate goal blood pressure should be Propranolol Broncboapasm, heart failure, masking of hypodetermined in each case; this could be either 90 mm Hg glycemic symptoms, bradycardia and unor less, or the lowest diastolic pressure in excess of potence 90 mm Hg that can be achieved without intolerable Iteserpine on (may be severe), gastric byperacF side effects. ty, drowsiness, nasal congestion, bradycar* The stepped-care regimen can be managed by dia andimpotence specially trained, appropriately supervised nurses as Methyldopa Drowsiness, abnonnal liver function, positive well as by physicians. results of direct Coombe' test, hemolytic anemia and impotence * Details of the stepped-care regimen, and appropriate revisions to it, should be supplied to every 146 CMA JOURNAL/JULY 21, 1979/VOL. 121
primary-care clinician in Canada. * Priority should be given to evaluations of the usefulness of treating hypertension at the worksite or in other nontraditional settings. DAVID L. SACKETT, MD, M Sc Departments of clinical epidemiology and biostatistics, and medicine McMaster University Hamilton, Ont.
References 1. American Medical Association, committee on hypertension: Drug treatment of ambulatory patients with hypertension. JAMA 225: '1647, 1973 2. Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure. A cooperative study. JAMA 237: 255, 1977 3. WRIGHT JM, MCLEOD PJ, MCCULLOUGH W: Antihypertensive efficacy of a single bedtime dose of methyldopa. Clin Pharmacol Ther 20: 733, 1976
The Canada Health Survey - can we get along without it? In 1974, the year in which health professionals all method of the survey have already been described;3'4 over the world began to read "A New Perspective on however, an answer to these questions should include the Health of Canadians",1 a group of federal health consideration of the purpose of surveys and of the scientists developed a proposal for an ongoing survey important questions that this survey might answer. of the health of Canadians. After approval by the Data on the health of populations are gathered in Cabinet in 1975, a joint team from Statistics Canada three ways: from rates of use of treatment facilities, and the Department of National Health and Welfare by analysis of vital statistics and through community developed a system for annually interviewing 12 000 surveys. The study of rates of treatment alone is very families; one third of the 12 000 would also undergo useful in the analysis of the medical care system and selected physical tests. After a successful pretest the in the planning for allocation of resources; however, survey was launched, in May 1978. Four months it cannot give an unbiased picture of the true rates later both agencies were notified that budget cuts of disease or disability, especially for asymptomatic necessitated the cancellation of the survey, and that or self-limiting conditions, in the population as a no funds would be forthcoming for analysis of the whole. Vital statistics are highly accurate and furnish data already gathered. a base for following trends such as birth and death In these days of lacerating budgetary sacrifices, one rates, which have a general significance for health; always hopes that a cut has found its mark, dismem- however, they offer no details on the causes and bering a superfluous program or exsanguinating a courses of disease and disability. Surveys, although nonproductive agency. Indeed, some of my colleagues dependent in part on the difficult art of interviewing,3 have pointed out that starting the Canada Health give a broad view of the distribution and determinants Survey would have committed the government to the of health and disease, and are the only means by cost of continuing a valueless long-term project. Some which health problems that fall outside the medical potential users initially questioned the content and care network can be studied. At present in Canada method of the survey; health care planners with a such data come from localized surveys and epidephilosophic orientation moaned that Canada is a small, miologic studies of limited scope: there has been no diverse and diffuse country that cannot know, or national view of health since the almost-forgotten does not need to know, more about the health of its Canadian sickness survey of 1950-51 *6 people; and some epidemiologists cited the apparent The overall objective of the Canada Health Survey uselessness of the proliferation of surveys sponsored was to gather data on health status that would be by the National Center for Health Statistics in the useful in evaluating and planning health care services, United States. However, the years of planning that health promotion activities and protective measures went into the Canada Health Survey, the relevance of for the population as a whole. An integral part of its objectives to the "Spirit of Lalonde",2 and its en- this approach was the relatively new view that health dorsement by the Canadian Public Health Association, status has both positive and negative measurable comthe Canadian Medical Association, professors of med- ponents.7 Knowledge of the causes and consequences icine and public health, provincial health agencies and of risk factors is also important in the planning of health interest groups suggest that the survey may preventive programs. The survey's data bank would not have been given a fair trial before it was dragged allow the testing of hypotheses and the examination of to the altar last September to have its heart cut out. associations so necessary in epidemiologic research What could the Canada Health Survey have done relevant to the study of the detection, distribution and for the people of Canada, and what, in fact, have we causes of disease. lost with its demise? The objectives, content and The working paper by the Canada Health Survey8 148 CMA JOURNAL/JULY 21, 1979/VOL. 121
The hypertensive patient: 4. Stepped-care therapy In their recommendations on the treatment of hypertension the Canadian hypertension task forces and committees* recognize four maxims. First, nearly all of the care of hypertension will be provided in primarycare settings, by either general practitioners or specially trained nurses. Second, the treatment regimens will involve antihypertensive drugs; although exciting progress is being made in determining the potential usefulness of nondrug strategies, they are not considered feasible at present. Third, because the execution of these recommendations may result in increasing drug ingestion by Canadians, we have sought "tried-andtrue" regimens whose efficacy and safety have been established by both large-scale randomized clinical trials and long-standing use. Fourth, we have attempted to keep these regimens simple in an effort to minimize cost, confusion and noncompliance. Stepped care is a regimen in which a single, mild antihypertensive drug is prescribed initially, then more powerful drugs are prescribed, if necessary, in a straightforward manner until a predetermined "goal" blood pressure is achieved. Stepped care has also been adopted by a number of advisory groups and health professional organizations elsewhere.1'2 The objective of stepped care is to maintain the level of diastolic blood pressure in the goal range by using the most efficacious therapeutic regimen for each patient. Hence, the treatment effect is maximized while undesirable and unpleasant side effects, the complexity of the treatment regimen, and the number and potency of agents used are minimized. The Canadian task forces recommend as a goal the achievement and maintenance of diastolic blood pressures less than 90 mm Hg or a decrease of 10 mm Hg, whichever is lower. The first step consists of administering a thiazide or related diuretic, usually at half the full daily dose, and then progressing in one step to the full dose, allowing a minimum of 2 weeks or a maximum of 6 weeks at each dose. In this way one can assess *Details pertaining to the hypertension task forces and committees may be found in the first of this series of articles on hypertension, published June 9, 1979. The entire series is appearing in consecutive issues of the Journal.
the efficacy of the drug for up to 12 weeks before concluding that the first step is not adequately effective. In the first step clinicians are advised to use the drug with which they are most familiar. A thiazide or related diuretic was used as the firststep drug for the following reasons: * A substantial proportion of less severely hypertensive patients (diastolic blood pressure 90 to 120 mm Hg) are satisfactorily controlled by a thiazide diuretic alone. Thus, the patient may have to take only one tablet a day. * Thiazide and related diuretics are generally mild antihypertensive agents that have flat dose-response curves, such that dosage is not critical and response tends to be stable. * Side effects associated with thiazide-type agents are relatively mild and uncommon. * Should one or more additional drugs be required, their effect on decreasing the blood pressure tends to be at least additive to, and may be potentiated by, that of the diuretic; the blood pressure goal may be achieved at doses below those associated with unacceptable side effects. * Thiazide and related diuretics have been available for several years, are well known and widely used by primary-care clinicians, and have been the backbone of active therapy in randomized trials demonstrating the benefits of antihypertensive drug treatment. All thiazides are basically equipotent and have a similar spectrum of side effects - hypokalemia and increased risk of muscle weakness; increased serum uric acid concentration and increased risk of symptomatic gout; decreased glucose tolerance and increased risk of diabetes mellitus; raised blood urea nitrogen concentration; photosensitivity; increased serum calcium concentration; occasional gastrointestinal irritation; and, rarely, blood dyscrasias or pancreatitis. Hypokalemia is an uncommon side effect of treatment with thiazides, and potassium supplementation is seldom required, especially if the dietary potassium intake is increased. However, if a patient is also receiving digitalis, the administration of potassium supplements or the addition of a potassium-sparing diuretic (spironolactone or triamterene) is mandatory. Should potassium depletion (serum potassium concenCMA JOURNAL/JULY 21, 1979/VOL. 121
145
tration 3.0 mmol/l or less) occur a potassium-sparing is added as step 3. Hydralazine is a direct vasodilator diuretic may be added, in which case potassium supple- and may therefore reflexly increase cardiac work. It ments should be discontinued and a close watch kept should therefore be used with caution in persons with on the serum potassium concentration. Again, clini- ar.gina or congestive heart failure. Other side effects cians are advised to use drugs with which they are include headaches, insomnia and the occurrence of a familiar. "lupus-like" syndrome, which rarely occurs when doses If the therapeutic goal is not achieved with full-dose less than 300 mg/d are given. diuretic therapy alone, an assessment of the possible The combination of a diuretic, propranolol and causes of failure should be made before proceeding hydralazine has much to recommend it from both to the second step. The most common causes of failure theoretical and practical points of view, combining at the first step include: (a) poor compliance with the as it does a peripheral vasodilator and a /3-blocker prescribed regimen; (b) the patient's use of competing with significant direct cardiac action to reduce cardiac drugs (e.g., over-the-counter cold remedies) without output. The associated diuretic tends to reduce the the clinician's knowledge; (c) excessive salt intake; or required doses of the other drugs, and controls their (d) an intrinsic disease process whose control is beyond tendency toward fluid retention. the capability of diuretic therapy alone. If the first If the three steps do not control the blood pressure three of these factors can be excluded, another drug satisfactorily, the clinician must consider whether a should be added to the therapeutic regimen. further search for secondary hypertension is warranted. An adrenergic blocking agent - propranolol, a Furthermore, therapy should be individualized and a rauwolfia agent or methyldopa - is used in the consultation considered. Recommendations may include second step. There is no absolute preference among the administration of established drugs such as guanethese drugs, and the choice should be governed by thidine or newer drugs such as clonidine. Seldom would the drug's known mechanisms of action, potency and one of these drugs simply be added to the previous side effects, and the clinician's skill and experience three steps. However, the step 1 diuretic would usually with these drugs. Prime consideration must also be be continued. given to patient convenience, including the cost of What about "stepping down"? Fundamental to the drug and the frequency of administration. Propra- stepped-care therapy is the periodic reassessment of nolol can be taken twice a day and the rauwolfia the patient's blood pressure and the appropriate adagents once a day. Methyldopa is usually given four justment of therapy by "stepping" the regimen either times a day, but recent evidence suggests that it may "up.. or "down... With few exceptions, once the need be taken less frequently.3 The frequency of administra- for therapy has been established it must be life-long. tion may become paramount in determining adherence However, it often may be possible to "step down" the to the treatment program. drug therapy, and this should be done whenever it is At the time this report was in preparation, the use possible to do so without compromising control. of rauwolfia agents was decreasing, and insufficient Follow-up must therefore be regular and systematic, experience with the cardioselective /3-blocking agents the interval between visits usually being 2 months and had accumulated to permit a definitive recommenda- seldom more than 4 months once control is stable. tion. In asymptomatic patients in whom hypertension is The principle of the stepped-care approach should well controlled and stable, long-term follow-up can be followed conscientiously, beginning with the small- be effectively carried out by specially trained and apest dose, allowing enough time for the drug to have propriately supervised nurses. The value of providing its full effect, and then increasing to the next level stepped care in nontraditional settings (e.g., the workuntil an adequate decrease in blood pressure is site) should be determined. achieved. This will promote optimum action with minThe task forces and committees have made the folimum intake and side effects. Of course, a thorough lowing recommendations pertaining to stepped-care knowledge of the side effects of these drugs (Table I) therapy. is a prerequisite for their use. * A stepped-care antihypertensive drug regimen When hypertension is not controlled at the end of is recommended in which a single mild antihypertenstep 2 and poor compliance is not a factor, hydralazine sive drug (a thiazide) is initially prescribed, followed by more powerful drugs if necessary (propranolol, rauwolfias or methyldopa in step 2 and hydralazine Table l-.$lde effects of drugs used In step 2 in step 3), in a straightforward, stepwise manner until a predetermined "goal" blood pressure is achieved. Generic name Side effects * The appropriate goal blood pressure should be Propranolol Broncboapasm, heart failure, masking of hypodetermined in each case; this could be either 90 mm Hg glycemic symptoms, bradycardia and unor less, or the lowest diastolic pressure in excess of potence 90 mm Hg that can be achieved without intolerable Iteserpine on (may be severe), gastric byperacF side effects. ty, drowsiness, nasal congestion, bradycar* The stepped-care regimen can be managed by dia andimpotence specially trained, appropriately supervised nurses as Methyldopa Drowsiness, abnonnal liver function, positive well as by physicians. results of direct Coombe' test, hemolytic anemia and impotence * Details of the stepped-care regimen, and appropriate revisions to it, should be supplied to every 146 CMA JOURNAL/JULY 21, 1979/VOL. 121
primary-care clinician in Canada. * Priority should be given to evaluations of the usefulness of treating hypertension at the worksite or in other nontraditional settings. DAVID L. SACKETT, MD, M Sc Departments of clinical epidemiology and biostatistics, and medicine McMaster University Hamilton, Ont.
References 1. American Medical Association, committee on hypertension: Drug treatment of ambulatory patients with hypertension. JAMA 225: '1647, 1973 2. Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure. A cooperative study. JAMA 237: 255, 1977 3. WRIGHT JM, MCLEOD PJ, MCCULLOUGH W: Antihypertensive efficacy of a single bedtime dose of methyldopa. Clin Pharmacol Ther 20: 733, 1976
The Canada Health Survey - can we get along without it? In 1974, the year in which health professionals all method of the survey have already been described;3'4 over the world began to read "A New Perspective on however, an answer to these questions should include the Health of Canadians",1 a group of federal health consideration of the purpose of surveys and of the scientists developed a proposal for an ongoing survey important questions that this survey might answer. of the health of Canadians. After approval by the Data on the health of populations are gathered in Cabinet in 1975, a joint team from Statistics Canada three ways: from rates of use of treatment facilities, and the Department of National Health and Welfare by analysis of vital statistics and through community developed a system for annually interviewing 12 000 surveys. The study of rates of treatment alone is very families; one third of the 12 000 would also undergo useful in the analysis of the medical care system and selected physical tests. After a successful pretest the in the planning for allocation of resources; however, survey was launched, in May 1978. Four months it cannot give an unbiased picture of the true rates later both agencies were notified that budget cuts of disease or disability, especially for asymptomatic necessitated the cancellation of the survey, and that or self-limiting conditions, in the population as a no funds would be forthcoming for analysis of the whole. Vital statistics are highly accurate and furnish data already gathered. a base for following trends such as birth and death In these days of lacerating budgetary sacrifices, one rates, which have a general significance for health; always hopes that a cut has found its mark, dismem- however, they offer no details on the causes and bering a superfluous program or exsanguinating a courses of disease and disability. Surveys, although nonproductive agency. Indeed, some of my colleagues dependent in part on the difficult art of interviewing,3 have pointed out that starting the Canada Health give a broad view of the distribution and determinants Survey would have committed the government to the of health and disease, and are the only means by cost of continuing a valueless long-term project. Some which health problems that fall outside the medical potential users initially questioned the content and care network can be studied. At present in Canada method of the survey; health care planners with a such data come from localized surveys and epidephilosophic orientation moaned that Canada is a small, miologic studies of limited scope: there has been no diverse and diffuse country that cannot know, or national view of health since the almost-forgotten does not need to know, more about the health of its Canadian sickness survey of 1950-51 *6 people; and some epidemiologists cited the apparent The overall objective of the Canada Health Survey uselessness of the proliferation of surveys sponsored was to gather data on health status that would be by the National Center for Health Statistics in the useful in evaluating and planning health care services, United States. However, the years of planning that health promotion activities and protective measures went into the Canada Health Survey, the relevance of for the population as a whole. An integral part of its objectives to the "Spirit of Lalonde",2 and its en- this approach was the relatively new view that health dorsement by the Canadian Public Health Association, status has both positive and negative measurable comthe Canadian Medical Association, professors of med- ponents.7 Knowledge of the causes and consequences icine and public health, provincial health agencies and of risk factors is also important in the planning of health interest groups suggest that the survey may preventive programs. The survey's data bank would not have been given a fair trial before it was dragged allow the testing of hypotheses and the examination of to the altar last September to have its heart cut out. associations so necessary in epidemiologic research What could the Canada Health Survey have done relevant to the study of the detection, distribution and for the people of Canada, and what, in fact, have we causes of disease. lost with its demise? The objectives, content and The working paper by the Canada Health Survey8 148 CMA JOURNAL/JULY 21, 1979/VOL. 121
