Last week, various specialists in the treatment of hypertension and its complications gathered for the 24th joint annual convention of the Philippine Hypertension Society (PSH) and the Philippine Lipid and Atherosclerosis Society (PLAS).
Local and foreign experts had lively discussions on various controversial topics in a program prepared by Dr. Leilani Asis-Mercado, newly inducted PSH president, succeeding Dr. Abet Atilano.
I was privileged to be one of the plenary speakers, and took part also in discussions to dissect controversies. Despite advances in the diagnosis and treatment of hypertension, there are still a lot of unanswered questions.
What really is the normal blood pressure (BP)—less than 140/90 mmHg, as has been conventionally accepted, or 130/80 mmHg, as proposed by the most recent American guidelines?
My colleagues in the International Society of Hypertension (ISH) and I published a commentary on this, and we believe that the threshold should still be 140/90. This is especially pragmatic in underdeveloped countries where the control rate is only 15 percent.
If 130/80 were used as the new diagnostic threshold for hypertension, this will increase the prevalence worldwide by more than half. This can lead to a misallocation of meager resources in low-income countries. Instead of focusing medicines and treatments on higher-risk patients, many low-risk patients with a BP of 130/80 may be unnecessarily treated.
Single pill combinations
During the PSH-PLAS convention, Dr. Dante Morales, noted cardiologist, reviewed the latest European guidelines in his friendly debate with Dr. George Bakris, renowned hypertension expert and kidney specialist from the University of Chicago, who presented the American treatment guidelines. Both agreed that except for the top line of how hypertension should be defined, most recommendations in both guidelines are essentially the same.
Most hypertension specialists now agree that two drugs in a single pill combination (SPC) are now the preferred initial treatment for most patients, once the doctor decides that drug treatment is needed. The old dogma was to start with one drug, gradually increasing the dose to maximum tolerated levels, before adding a second drug.
However, practically all studies have shown that the majority of hypertensive patients will need two to three drugs to control their BP. Sticking to monotherapy will only delay control and may cause serious complications in as early as one to two years after diagnosis.
The delay in achieving control of high BP is called clinical inertia, which has been implicated in the development of severe irreversible complications in the heart, brain, kidneys and the network of arteries in the body. It is therefore recommended to urgently control high BP within three months in those with moderate to high cardiovascular risk.
The absence of symptoms, which is usually the case in most hypertensive patients, does not mean that one is low-risk. Many high-risk individuals walk around thinking they’re okay, not realizing they can have a heart attack or stroke anytime—the “walking time bombs.”
Every individual with raised BP should see their physician for risk assessment and BP control at least once a year or more frequently, depending on the cardiovascular risk.
The use of two- to three-drug SPCs can expedite control of high BP and help prevent long-term complications in moderate to high or very high- risk patients. This also enhances patient compliance because one has to take just a single pill with three drugs in it.
Only a minority of hypertensive patients should be given a single drug as initial treatment for hypertension. These are frail elderly patients, and those at low risk to develop complications like heart attack and stroke. Everyone else should be prescribed at least a two-drug combination.
Paradoxical increase
Everyone is cautioned, however, that bringing the BP down to less than 120/70 mmHg may lead to a paradoxical increase in cardiovascular complications, especially heart attacks. This is based on fairly robust data suggesting a tilted J-curve pattern in hypertension.
This pattern indicates that the complications decrease as you reduce the BP from elevated levels, but if you bring it down lower than a certain level, the complications increase. This nadir at which complications start appears to be less than 120/70 mmHg.
Personally, I think 130/75 is the “sweet spot,” but it can range from 120/70 to less than 140/80.
Experts also now believe that physicians should be less conservative in setting treatment targets for older patients. The old recommendation was to allow higher levels of BP for those aged 80 and above. However, data from clinical trials indicate that they are still more susceptible to strokes and heart attacks with previously recommended BP levels.
For so long as they can tolerate it—meaning, no significant side-effects like dizziness, weakness or blood electrolyte problems—their BP should be brought down to less than 140/80 mmHg, up to a systolic BP level of 130 mmHg.
The new American and European guidelines also recommend a wider use of out-of-
office BP measurement, including home BP monitoring, as an option to confirm the diagnosis of hypertension, detect the so-called “white coat” hypertension (elevated BP in the clinic but normal at home), and masked hypertension (normal or high normal BP in the clinic but elevated at home). Monitoring one’s BP at home is also a good way of involving the patient actively in the treatment of his hypertension, and promoting better treatment adherence.