Background: Lower socioeconomic status has been reported to favor higher blood pressure both during childhood and adulthood, because obesity is more prevalent among this population. The aim of the present study was to evaluate the effect of socioeconomic status on blood pressure and prevalence of obesity among children living in a developing country.
Methods: Prepubertal primary school children (total number 1024, male/female ratio 513/511, mean age 10.32 +/- 0.60 years) living in Izmir, a metropolis of Turkey, were enrolled in the present study. The children were classified into three groups according to the locations of their schools as those from the well-developed (WD; n = 290), moderately developed (MD, n = 356) and underdeveloped (UD, n = 378) areas. Body mass index (BMI), ratio of BMI to the 50th percentile value of BMI for that age (BMI%) and systolic (SBP) and diastolic blood pressures (DBP) were determined in all children. Each socioeconomic group was subdivided into three subgroups with respect to BMI% as those with less than 90% (SG(< 90)), 90-110% (SG(90-110)), and more than 110% (SG(> 110)). Then, mean SBP and DBP in each subgroup of the WD, MD and UD groups were compared with the corresponding blood pressure values of each other to evaluate the effect of socioeconomic status on the blood pressure. In addition, the SBP and DBP of each subgroup were compared with other subgroups within that group to evaluate the effect of BMI on blood pressure.
Results: The BMI and BMI% of the UD group were significantly lower than that of the WD and MD groups (P < 0.05). In addition, the number of children with a BMI of more than 95% for their age was significantly lower in the UD group compared with the WD and MD groups (1.7, 1.9 and 0.5% in the WD, MD and UD groups, respectively, P < 0.05). The SBP and DBP were positively correlated with BMI% in each group and in all of the subjects cumulatively (r = 0.26, P < 0.001 for SBP and r = 0.34, P < 0.001 for DBP). The SBP and DBP were significantly higher in SG(> 110) than in SG(90-110) and were also higher in SG(90-110) than in SG(< 90) in each group. Mean DBP values in all subgroups of the MD and UD groups were significantly lower than the respective subgroups of the WD group. The SBP of SG(< 90) and SG(90-110) of the UD group were significantly lower than those of the corresponding subgroups of the WD and MD groups.
Conclusion: Obesity is not more prevalent among the children of lower socioeconomic classes in Turkey as a developing country. In addition, independent of anthropometric structure, DBP and SBP were shown to be related to the socioeconomic status in childhood age groups and both values were determined to decrease in accordance with a decrease in the socioeconomic level.