Consultancy Corner: Adult hypertension – its overview and primary prevention

The low- and middle-income countries bear disproportionately higher burden of hypertension in absolute numbers due to a rapid increase in prevalence and the sheer size of its population. The incremental burden of hypertension in these countries is attributed to the rising population level mean blood pressure (BP) especially in the South Asian and sub- Saharan population.

Despite progress in recent decades in prevention, early detection, and treatment of high BP, hypertension remains an important global public health challenge. Hypertension is said to be a disease of paradoxes which means it is easy to detect but diagnosis rates are dismal, easy to treat but treatment rates are disappointing and several potent drugs are available but control rates are abysmal. Moreover, the treatment and control rates of hypertension are abysmally poor at the population level especially in low and middle income nations.

Reducing the population level BP is an effective strategy in addressing the burden of hypertension. Although, taking medicine is effective in reducing BP in the hypertensive group, its impact on population mean BP reduction is limited. Primordial and primary prevention are key strategies for population-wide reduction in average BP.

Data on annual incidence of hypertension in Indian population are scarce. In a longitudinal follow-up study conducted in a representative sample from two cities of India (Delhi and Chennai), the average BP increased by 2.6 mm Hg and one in six developed hypertensions. The estimated impact of 2.6 mm Hg rise in average BP on hypertension prevalence is large as it could double the current prevalence rate of 30% over a period of 10 years.

The most susceptible group to develop hypertension is the least privileged, lesser educated, and from the lowest socioeconomic strata. This will have important ramifications at the population level, due to lesser likelihood of treatment affordability. Additionally, there is a tendency to ignore treatment options among the above mentioned group due to asymptomatic nature of hypertension and could potentially lead to devastating health consequences. The impact of a major cardiovascular event due to uncontrolled hypertension on household economy is substantial as it takes away potentially productive life years and probable bankruptcy due to huge out of pocket payments for treatment.

Primary prevention of hypertension provides an avenue to interrupt and prevent the continuing expensive cycle of managing hypertension and its complications. In order to achieve this, concerted efforts must be undertaken not only in earlier detection and treatment of hypertension, but also in implementation of primary prevention strategies.

Primary prevention focuses on preserving good health by removing the precipitating causes or potential determinants of poor health. The larger goal of primary prevention efforts in hypertension is to curtail the growing incidence of hypertension in India.

There are two main approaches in the primary prevention of hypertension.

The first one is known as the population based approach of involving the general population. The second approach is a targeted approach among high-risk individuals who are prone to develop hypertension. Higher risk older adults are more likely to be successful with lifestyle interventions than young adults with lower risk. However, prevention strategies targeted earlier in life for overall risk reduction and burden of BP-related complications in the community.

The key strategies for primary prevention of hypertension are-

Salt reduction is unequivocally the most efficient primary prevention intervention at the population level for hypertension.

The relationship between high alcohol intake (three or more drinks per day) and elevated BP has been documented in many epidemiologic studies.

Regular aerobic physical activity for at least 30 min/day for at least 5 days of the week has been recommended for primary prevention of hypertension.

The diet which is rich in fruits, vegetables, dietary, and soluble fibre, and low-fat dairy products but reduced in saturated and total fat is demonstrated to be effective in reducing mean BP in both hypertensive and normal individuals.