[JM 1]Hypertension and the Asia Pacific region

Cardiovascular disease remains one of the leading causes of mortality in the Philippines. Dr. Rafael Castillo, during his presidential lecture delivered at the 10th Asian-Pacific Congress of Hypertension last February 12 to 15 in Cebu City, likened hypertension to a storm surge. Every year, close to 120,000 Filipinos die due to complications related to hypertension. Non-optimal control of blood pressure imposes a huge socioeconomic burden as it causes disruption of work, family and social relationships.

Hypertension in the Asia Pacific region
The latest survey conducted by the Council on Hypertension of the Philippine Heart Association showed that the prevalence of hypertension in the country increased from 17 percent to 28 percent over the last 10 years. “The treatment and control rates may have improved but that means that we still have a lot of patients who remain undiagnosed [and] who remain untreated,” remarked Castillo.

“Globally and in the [Asia Pacific] region, cardiovascular disease still remains to be the leading cause of mortality. And there seems to be no sign that we’re making any significant progress in calming the tide of cardiovascular disease. That’s why we call it a storm surge…. And that means that we have to address it with a serious sense of urgency,” said Castillo.

He then encouraged Asia-Pacific countries to have a shift in health infrastructure and national policies towards prioritizing cardiovascular diseases. “Globally and in the Asia Pacific region, the forecast is that we will have more hypertensives by the year 2025. It is expected that there will be a 50 to 65 percent increase in the hypertensive population in the region,” he noted.

Castillo cited studies which show that Asians may be at a greater risk of hypertension-related complications, such as strokes or cerebrovascular complications, compared to Caucasians. [Hypertension 2007; 50:991-997] In another study, Asian patients develop more hemorrhagic strokes compared to Caucasians. The latter may develop more coronary artery disease. [Hypertension 2007; 25:73-79] This may in turn lead to a permanent or complete disability which implies a serious socio-economic burden.

Compounding the problem of hypertension in Asia Pacific is the problem of overweight and obese patients who experience twice the complications of hypertension.

Effective hypertension management
Several barriers affect the management of hypertension. One of these is the high incidence of cough with angiotensin-converting enzyme inhibitors (ACEi) among Asians, compared to Causasians, Blacks or Hispanics. “In China, the incidence of cough can be as high as 50 percent,” said Castillo.

Managing hypertension in a low-resource setting is also a challenge as the society has to address an ideal control strategy. “This is a challenge... when the resources are scarce, we have to be able to identify those who are high-risk to develop complications so that we can prioritize treatment of these patients,” said the speaker.

Simple risk assessment tools are being developed and may help identify high risk patients without the need for expensive laboratory tests. This way, patients who need treatment can be identified and prioritized.

The 24-hour ambulatory blood pressure monitoring may also not be feasible in low-resource settings where there are problematic cases of hypertension. As an alternative, Castillo suggested the use of home blood pressure monitoring. This can be done by two consecutive seated measurements at least 1 minute apart using either a manual or a digital sphygmomanometer. The blood pressure reading can be taken twice daily for a week. This monitoring will help the physician arrive at the average blood pressure, ruling out ‘white coat’ hypertension in the process.

The control of salt intake was described by Castillo as “one important intervention which will not cost much but will significantly help control the blood pressure.” Based on Japan’s experience, decreasing the daily salt intake from 26 grams to 12 grams per day reduced the systolic blood pressure by 18mmHg in both genders. Stroke rates were also reduce by 83 percent. [APSH Workshop, 2007]

“There is a direct relationship between stroke mortality rate and the level of sodium measured by urinary excretion as grams of salt per day. It’s not only for stroke but CHD events and all-cause mortality [which] can be significantly reduced by salt intake,” said Castillo.

The Japanese approach is doable, noted Castillo, but it requires time. The integrative approach include intensive and sustained public education, food delivery system, refrigeration, exposure to global eating habits, and provision for low-salt alternatives. [APSH Workshop, 2007]

Eighty-percent of a person’s salt intake comes from packaged and restaurant food and only about 10 percent comes from the salt added during cooking. Castillo said that the Food and Drug Administration (FDA Philippines) can try to require manufacturers to indicate on their product labels the amount of sodium. This way, consumers can have informed choice.

The polypill may also benefit patients with hypertension. These are safe, inexpensive and easily dispensed, requiring minimal follow-up. “This is one tool that companies with scarce financial resources can utilize. [Using submaximal doses of a few antihypertensives] might be better than maximizing the dose of one antihypertensive drug and that can favorably impact the decreased coronary hearts disease events and strokes in hypertensive patients,” said Castillo.

The multifaceted preventative and treatment programs for hypertension control include intensified lifestyle interventions, reduction of salt intake by 50 percent, increased potassium intake, decreased saturated fat intake and increased physical activity. Aside from individual patient education, Castillo stressed the importance of involving the community and its leaders, the food industry and the law-making bodies.

A vision for Asia Pacific
The vision of the Asia Pacific Society of Hypertension is to decrease the prevalence of hypertension and significantly reduce the disease burden caused by hypertension and related complications. There must be strong political and social will as well as population intervention. Patients must be treated holistically for cardiovascular risk reduction.

Castillo encouraged physicians to become “facilitators for change,” playing an active role in integrating multisectoral strategy for individual, community and population control of hypertension.

“We may not be able to solve the entire problem completely by ourselves but we can take the initiative to serve as the catalyst, to move everyone to rally behind the cause and goal of controlling hypertension in the population,” concluded Castillo.