By Dr Yoong Lee Yeen / Professor Dr Moy Foong Ming / Professor Dr Noran Naqiah Hairi

Emphasizing the "critical period" and "sensitive period" of an individual's life, tailoring the needs in these critical and sensitive periods is the game changer in combating hypertension.¹ Hypertension is a silent killer as many are unaware of it. It increases the risks for cardiovascular diseases, stroke, kidney failure, blindness, and even premature death. Hence, regular blood pressure measurement and knowing the numbers are essential to detect hypertension early.

Globally, it is estimated that 1.13 billion people have hypertension, with two-thirds of them from low- and middle-income countries (LMICs).² According to the 2019 National Health and Morbidity Survey, 30 percent (around 6.4 million) of Malaysian adults aged 18 years and above have hypertension, and the prevalence increases with age.³

Is targeting healthy lifestyle behavior during adulthood period alone sufficient? The answer is NO. The ideal way to effectively prevent hypertension should target the critical and sensitive periods, besides adulthood of an individual. What does this mean?

The "critical period" is the life stage when "biological programming" occurs, bringing long-lasting health effects. In terms of hypertension, the phases of preconception and pregnancy of a woman are the "critical phase". One's susceptibility to non-communicable diseases could be determined in the womb, this depends on maternal health.^1,4,5 So, it is best to intervene during the preconception period focusing on healthy behaviors among the women in their reproductive age group, besides preparing them nutritionally before conception. Antenatal care inclusive of maternal nutrition and reducing environmental exposures to risk factors such as smoking (including second-hand smoke) should be emphasized. Encouraging a healthier lifestyle for women preparing for pregnancy and during pregnancy has a protective effect on the susceptibility of hypertension of their offspring later in life.

Apart from the "critical period", the "sensitive periods" could make a substantial difference in the further development of disease risks. Infancy is among the "sensitive periods" in which breastfeeding could provide a protective effect for the children developing hypertension in later life.^1,4 Thus, it is crucial to encourage exclusive breastfeeding for the first six months of life and continue breastfeeding for two years.

As the children grow, they learn from role models such as their parents and older siblings and imitate their behaviors too. They tend to be more likely to perceive high risk behaviors (like unhealthy eating, tobacco smoking and alcohol consumption) in their early childhood from the family as norms and practice this throughout their life-course.⁴ Thus, the key to change is to create a health-promoting environment within the family during the "sensitive period" of childhood.

The adolescence phase is another "sensitive period" for behavioral change. Many studies showed that the adolescence phase is a crucial phase for moulding healthier lifestyle and behavior.^1,4 Early health education and awareness on hypertension during the adolescence phase can reduce the risk of developing hypertension in adulthood. Incorporating a healthy lifestyle into the school educational syllabus to enhance their knowledge, attitude, and practice of a healthy lifestyle can prevent hypertension much earlier.

During adulthood, health promotion enhancing hypertension awareness and regular health screening, blood pressure measurement and accessibility to treatment for hypertension could work to fight against hypertension.⁵ Empowerment of adults at the higher education institutions, workplace and community could create a more health-aware society to prevent hypertension.

In summary, as early prevention of hypertension among the population, we could do more across the life phases as below:

1. Promote healthy behaviors and maintain good nutritional status during reproductive age before conception for women;

2. Enhance maternal health in getting balanced nutrition and reducing the exposure to harmful substances;

3. Encourage breastfeeding;

4. Be a good role model and provide a health-promoting growing environment for the children to instill healthy behavior since young;

5. Educate and inspire adolescents to practice a healthier lifestyle; and

6. Empower the adults to improve the awareness of hypertension, practice healthy lifestyle (healthy diet, exercise, maintaining healthy weight, quit smoking and no consumption of excessive alcohol) and regularly measure blood pressure.

Targeting the critical and sensitive periods increases the effectiveness of hypertension interventions throughout a person's life, emphasizing a healthy start to life, tailoring the needs of individuals in each life stage. Let's take action early, appropriately during the life phases, and together as a whole society!

References:

¹ Mikkelsen, Bente, Williams, Julianne, Rakovac, Ivo, Wickramasinghe, Kremlin, Hennis, Anselm, Shin, Hai-Rim, . . . Breda, João. (2019). A life-course approach to prevention and control of non-communicable diseases. BMJ, 364, l257. 

² World Health Organization. (2019). Hypertension.

³ National Institutes of Health. (2020). National Health and Morbidity Survey (NHMS) 2019 Technical Report (Vol. Volume 1).

⁴ Jacob, CM, Baird, J, Barker, M, Cooper, C, & Hanson, M. (2017). The importance of a life course approach to health: chronic disease risk from preconception through adolescence and adulthood. World Health Organization, 1-41.

⁵ Olsen, M. H., Angell, S. Y., Asma, S., Boutouyrie, P., Burger, D., Chirinos, J. A., . . . Wang, J. G. (2016). A call to action and a life-course strategy to address the global burden of raised blood pressure on current and future generations: the Lancet Commission on hypertension. Lancet, 388(10060), 2665-2712. 

(Dr Yoong Lee Yeen, Professor Dr Moy Foong Ming and Professor Dr Noran Naqiah Hairi, Center of Epidemiology & Evidence Based Practice, Department of Social & Preventive Medicine, Faculty of Medicine, Universiti Malaya.)