Hypertension is among the leading causes of death globally. It increases risks of stroke, heart diseases, kidney failure and other diseases [1, 3]. Slightly more than one in every four adults aged 35 years or older had hypertension in Gondar city (28.3%). This prevalence is high and may be considered as a major public health problem in this community. As a result complications of hypertension such as disabilities are more likely to occur in this community particularly among those not aware of being hypertensive .
This result was comparable with a community-based study conducted in Addis Ababa, Ethiopia which reported a 31.5% and 28.9% prevalence of hypertension among males and females, respectively . It is also comparable with a 29.3% prevalence report from the United States . This may be due to the fact that the prevalence of hypertension in this country is getting due attention only recently and may still be raising while that of the USA is declining with treatment and life style modifications.
Prevalence of hypertension in this study is considerably higher as compared to previous reports from southern Ethiopia (10.1%), Vietnam (14.1%) and Jordan (23.9%) [11–13]. This discrepancy may be explained in two ways; First, the age difference in the study populations (>=35 years in our case while in other studies age of participants ranges between 18–65 years). Secondly, this study was conducted only in an urban setting.
This prevalence was lower than other similarly community based studies conducted in Uganda, Mozambique, Eastern Nigeria and Northern India in which the prevalence of hypertension ranged from 30.5 to 44.5%) [14–17]. This difference may be attributable to higher prevalence of obesity (Nigeria, 13.3%) on top of this, racial and genetic difference which could probably affect blood pressure.
As many studies agreed, there is a positive association between age and hypertension [12, 13, 15, 18] in which the risk of hypertension increases with age. This is mainly due to arterial stiffness as one gets older. Hypertension was 9% higher among those aged 45–54 years compared to those 35–44 years old, while it increased by 20% in those 55 years or older compared to those 45-54 years of age category. In the current study, obese people had a 5.5 times higher risk of hypertension compared to those with normal BMI. Obesity was more prevalent among females but its effect on hypertension was more pronounced among males (76.3% and 23.7% of obese males and females were hypertensive respectively). This made hypertension more or less similar across both sexes. This finding was in line with previous reports from Ethiopia, Eretria, Uganda and India [9, 17–20]. Similar to other previous studies reported so far [11, 12, 21], family history of hypertension was significantly associated with being hypertensive in this study.
People who reported having diabetes were about 4 times more likely to have hypertension as well. In this study, 66% of those who reported being diabetic had hypertension. This might be due to the fact that both diseases share common risk factors and/or due to the fact that the two conditions (diabetes and hypertension) may cause each other [2, 3]. This finding is in agreement with several other studies [12, 19, 20]. This study also revealed that walking for at least ten minutes continuously everyday was negatively associated with hypertension. This study further strengthens the previous reports in this country [9, 11].
Unlike other studies done so far [11, 16, 17, 22], cigarette smoking, harmful use of alcohol and excessive use of salt were not significantly associated with hypertension in this study. This may be due to the low prevalence of these factors in the community studied.
This study has potential limitations. Firstly, being a cross-sectional one it has inherent limitation; hypertension might have preceded some of the explanatory variables. Second, this study is limited to behavioral and physical measurements, and did not include biochemical measurements such as a 24 hours urine sodium concentration, serum glucose level, etc. Thirdly, it was only limited to adults aged 35 or older which made comparisons with other studies difficult.