Prevalence of PHTN and HTN
The current findings highlighted a significant burden of both PHTN and HTN in the studied population. The present findings showed that the prevalence of PHTN was 29.8%, which was similar to the figures reported elsewhere [14, 16, 21, 22]. However, this result was lower than the figures reported in the neighboring Arabian Gulf countries (37.4%, 45%, and 54.9% in Bahrain, Oman, and Saudi Arabia, respectively) [23–25]. Regarding the prevalence of HTN, the present data also revealed that it affects about one-third (32.5%) of adults in Dubai. This is comparable to the results from other countries worldwide [12, 26–28]. Our prevalence lies within the range of HTN reported in the Gulf States (26.1%, 34%, and 37% in Saudi Arabia, Oman, and Kuwait, respectively) [24, 29, 30]. The differences observed in the prevalence between the Dubai population and other studies with respect to PHTN and HTN could be attributed to dietary and lifestyle factors, cultural and social differences, and the adopted research methodologies. It is worth mentioning that, the proportion of adults with HTN in Dubai was higher than the national average for the UAE of 28.8% . This might be due to the slightly different demographics and dynamics of the population of Dubai compared to the other Emirates .
Risk Factors Associated with PHTN and HTN
In the current survey, the logistic regression analysis showed that age, gender, occupation, and BMI were significantly associated with the risk of having HTN. However, physical activity was shown as a protective factor. At the same time, occupation and BMI were the only associated factors with PHTN. The current findings showed that advanced age was associated with an increased risk of HTN. Almost all the studies carried out in different populations had shown a somehow consistent increase in BP with aging [21–28]. Vascular abnormalities might contribute to the high prevalence of HTN in the elderly .
Data from the survey revealed a huge gender gap in HTN prevalence between males and females in Dubai. Males were found to be five times more likely to be hypertensive than females. Other studies have confirmed these findings [21–25, 30]. The gender differences in hypertension are mainly due to biological factors including sex hormones that keep lower levels of HTN in women, among other factors [34–36]. Behavioral risk factors, including high BMI, smoking, alcohol consumption, and physical inactivity, differ in complex ways between males and females as they play some protective effects in women [26, 34–36]. In addition, women utilize healthcare services more frequently which could have a positive effect on controlling diseases like HTN [27, 34].
The present study showed that being overweight was associated with both PHTN and HTN. However, obesity was proven only as a risk factor for HTN within our population. This can be explained by the fact that obese individuals could progress quickly to the actual HTN from the PHTN status . It is worth noting that, 62.1% of adults in Dubai are either overweight or obese (41.3%, 20.8%, respectively) . International studies revealed a direct association between increased BMI and HBP and identified obesity as a major risk factor for HTN and PHTN [24–29]. The mechanisms by which obesity contributes to the development of HTN including insulin resistance among other pathophysiological changes [38, 39].
Compared to professionals, skilled and service workers endured a higher risk for both PHTN and HTN within the current population. The influence of occupation as a predictor for high BP has rarely been stated in other studies [26, 30, 40]. Given that there are some variations in the definitions of the occupational categories among different studies, contradictory findings have been reported regarding this association [14, 41]. Similar to the present results, service occupations had a significantly increased prevalence of HTN [41, 42]. However, other studies found that unskilled workers were found to have more HTN than professionals and managerial ones [43, 44]. The difference in job strains, work environment, and levels of decision-making are among the factors that underlie the differences in HTN prevalence by occupations .
In the current study, physical activity was significantly inversely associated with the risk of developing HTN. Consistent evidence from research has endorsed the favorable effects of exercise and physical activities on the control of BP and prevention of HTN [14, 15, 46, 47]. Still, there are many unaddressed questions in the nature of the association between physical activity and prevention of HTN in terms of the types, levels and duration of physical activity needed, particularly in high-risk individuals .
Unexpectedly, the current findings showed that smoking and alcohol drinking was not associated with PHTN and HTN within the population of Dubai. Our results were not in agreement with other studies [14, 26, 48], since some existing evidence shows that smoking and alcohol drinking were among the risk factors for high BP. The discrepancy between our results and other studies might be explained by the existence of a social stigma attached to smoking and alcohol drinking, especially among females in the Arab region. Therefore, smoking and alcohol drinking could be underreported among the Dubai population .
This study has few limitations. First, the survey used data derived from both self-reports and physical measurements. The information collected on a self-reported basis is subjected to some form of bias. Subjectivity, underwriting, or misreporting associated with self-reporting cannot be ignored. A second limitation is that the survey did not collect some important variables such as the family history of HTN, salt and dietary intake of the studied population. Finally, as this survey used a cross-sectional design, the cause and effect relationship could not be established. Despite the above limitations, the strength of this study lies in that it is based on a population survey, which allows a representative population sample. In addition, the current study is the first study to shed light on the prevalence of PHTN and HTN and their correlates at the population level in the emirate of Dubai.