Prehypertension and psychosocial risk factors among university students in ASEAN countries

Several studies have shown an increase in the prevalence of hypertension in high and low and middle income countries [1, 2]. Similar to the trend worldwide, “hypertension is also the single most attributable cause for mortality in South-East Asia. But while in developed regions, the prevalence of hypertension appears to be stabilizing or decreasing, the rates in Southeast Asia continue to rise” [3]. If you are prehypertensive, you are more likely to become hypertensive and have a higher cardiovascular risk (compared with normotensives), and comprehensive therapeutic lifestyle modification strategy in prehypertensive subjects is indicated to reduce the risk of developing hypertension [4, 5]. In addition, studies found that hypertension and prehypertension can start in adolescence (or earlier) and continue into adulthood [6]. A study among young adults (20–30 years) found that students were at higher risk for prehypertension than the general youth population [7].

Currently, there are few studies on the assessment of prehypertension in young adults or university students in Association of Southeast Asian Nations (ASEAN). For example, in Malaysia the prevalence of prehypertension among university students was found to be 30.1% [8] to 42.9% [9], in the Philippines 13.9% [10] and in Thailand 44.5% [11]. Among Indian medical students a prehypertension prevalence rate of 45% [12] and in another study among male undergraduate students in India 55.1% [13] was found. Studies among university students in the Middle East found a prehypertension prevalence of 47.4% in Egypt [14], 39.5% in Kuwait [15], and 13.5% among females in Saudi Arabia [16].

Psychosocial risk factors associated with prehypertension or hypertension among university students and general adult population may include sociodemographics such as male gender [15, 17], nutrition variables such as Body Mass Index (BMI) overweight/obesity [7, 12, 15, 16, 18, 19], excess sodium intake [7, 20], inadequate intake of fruit and vegetables [13, 20], and health risk behaviour variables such as physical inactivity [20, 21], substance use, including smoking [15, 22], heavy alcohol use [23, 24] and short sleep duration [23, 25, 26]. Psychosocial stress and support may include depression [8, 27, 28], posttraumatic stress disorder (PTSD) [29], low life satisfaction [30], and lack of social support [25, 31, 32].

As a result, the purpose of this study was to evaluate the prevalence of prehypertension, hypertension and to identify psychosocial risk factors for prehypertension based on a cross-sectional survey of a university undergraduate population in ASEAN countries (Indonesia, Laos, Malaysia, Myanmar, Philippines, Thailand and Vietnam).

The study found among a large sample of undergraduate university students across seven ASEAN countries a prehypertension prevalence of 19.0%, which seems generally lower than previous in the region [8, 9, 11–13] and in the middle east [14, 15]. There was some country variation in prehypertension prevalence, ranging from 11.3% in Indonesia and 11.5% in Malaysia to above 18% in Laos, Myanmar and Thailand. Students residing in upper middle income countries such as Thailand had a higher prevalence of prehypertension than those in lower middle income countries. These country differences in terms of prehypertension prevalence may be attributed to different stages of the epidemiologic transition of the participating student populations in the various countries. As found in some previous studies [15, 17], this study found a significant higher prevalence of prehypertension among male (28.7%) than female (13.9%) students. Nevertheless, a large proportion of, especially male, university students in ASEAN countries seem to suffer from prehypertension requiring comprehens ive lifestyle modification programmes [4].

Compared with students who were residing with their parents or guardians, students who were living on campus or off campus on their own were at a higher risk for prehypertension. It is possible that students living away from their parents are more influenced by their peers in terms of lifestyle changes increasing the development of prehypertension. Regarding weight variables, being underweight was protective and being obese increased the odds of having prehypertension. The association between overweight/obesity and prehypertension and hypertension has been confirmed in a number of studies [7, 12, 15, 16, 18, 19]. Further, having once or more times soft drinks in a day increased the odds of prehypertension and moderate consumption of chocolate or candy (1–6 times a week) was protective of prehypertension. In a systematic review, Ried et al. [48] found that “flavanol-rich chocolate and cocoa products may have a small but statistically significant effect in lowering blood pressure by 2-3 mm Hg in the short term.” Unlike a few previous studies [7, 13, 20], this study did not find an association between excess sodium intake, inadequate intake of fruit and vegetables and prehypertension. A previous study [49], found an association between sodium intake and hypertension in the older age group but not in the younger age group, so it is possible that other risk factors (such as obesity) for raised blood pressure play a larger role than sodium intake at the age of young adulthood [50]. Another study among Chinese adults also did not find an association between salt intake and prhypertension [51]. Another possible reason for this result could be recall bias resulting from self-reporting of salt intake [51].

Regarding health risk behaviours, this study found that heavy drinking students had an higher odds of having prehypertension, as also found in previous studies [23, 24]. Although current evidence suggests that the moderate consumption of alcohol lowers the blood pressure, chronic ethanol consumption (≥ three drinks a day) is associated with an increased incidence of hypertension [52]. Tobacco use was found in bivariate analysis associated with prehypertension prevalence, as also some previous studies found a significant association [15, 22]. Unlike several previous studies [20–23, 25, 26], this study did not find an association between physical inactivity, short sleep duration and prehypertension. However, several other studies also did not find a clear association between physical inactivity and raised blood pressure [53, 54]. It is possible that the driving force behind increased blood pressure in this study population is not solely physical inactivity but is linked to other factors such as obesity, which still can be advocated for in order to improve a healthy body [53]. Further, in a previous review [55], it was found that the association between short sleep and higher blood pressure and hypertension was stronger among middle aged adults, which could possibly mean that among a younger age (emerging adulthood) effects of short sleep on raised blood pressure are not yet found.

In terms of psychosocial stress and support, this study found in agreement with previous studies [8, 27, 28] that depression was positively related to prehypertension. “There is considerable evidence suggesting that hyperreactivity of the sympathetic nervous system and genetic influences are the underlying mechanisms in the relationship between depression and hypertension.” [56] Further, in bivariate analysis this study found and association between low life satisfaction, and lack of social support and prehypertension, as found in previous studies [25, 30–32].

The study found high prevalence, in particular among men, of prehypertension in a large sample of university students across seven ASEAN countries. Often, in university students, prehypertension may not be discovered until late. This is because university students are generally healthy and will normally not go for a routine health check-up. The data from this study draws attention to the importance of examining the blood pressure of young persons. Several psychosocial risk factors including male gender, obesity, soft drinks consumption, heavy drinking and depression symptoms have been identified which can help in intervention programmes.