Although EBP in this age group appears to be minimal yet EDBP was detected in girls (5.1%) and not in boys (0%) with no ESBP in either sex. Moreover, it was detected in the girls exposed to CMFF in their infancy but not in those who were fully breastfed. Prehypertension or pre-ESBP (> 90-95th centile) was detected in one quarter of the cases (22.2% in boys and 26.9% in girls) and pre-EDBP in one third of the cases (29.2% in boys and 35.9% in girls). Such findings coincide with the findings of other studies who reported that the pooled global prevalence of EBP among children was 4.00% [14]. However, studies for EBP in preschoolers have not been reported in Egypt. A cross-sectional study of 1500 adolescents (11–19 years) in Alexandria in Egypt reported that prevalence rates of prehypertension and hypertension (HTN) were 5.7% and 4.0% [15]. The Demographic health survey in 2008 reported that HTN in the 11–19 females was (3.8%) and males (4.9%) [16]. Findings from analysis of demographic surveys conducted in 2015 indicate that overall prevalence of HTN in Egypt is 26% and that more than half of Egyptian adults who meet criteria for HTN are unaware of their BP status. Younger, healthier, and normal weight people-who are typically at lowest risk for HTN-appear mostly likely to be unaware of their HTN status. Less educated people are least likely to know their hypertensive status [17].
Our cases with Doppler findings of CHD did not show any significant elevations in BP. It is ideal to compare our results with standards developed from our own locality. The trend of Egyptian SBP and DBP nanograms, differ from Turkish [18] and American nanograms[19]. The latter Task Force values were based on nine different populations, including African and Mexican Americans. They used the first BP reading and not the average of two readings as in the Egyptian study. The rise in BP with increasing age is most probably caused by the growth of the child. It is accepted that the most influential determinants of normal BP are chronological age and body size as determined by height, weight and BMI [20].
This study showed that early breastfeeding and full breastfeeding was associated with lower tendency towards EBP. There were no significant echocardiographic studies. However, a study on which echocardiographic studies were conducted for 76 healthy infants aged 6 to 24 months of life of whom 38 were fed only breast-milk and 38 who were CMFF in the first six months of life showed some differences in right ventricular (RV) studies. Percent fractional shortening (%FAC) for right side was significantly higher in fully breastfed infants compared to the CMFF (P < 0.05). There was a significant increase in the mean RV Velocity time integral (VTI) values in EBF infants (17.2 ± 2.73) than CMFF infants (15.9 ± 1.94) P < 0.01; the cardiac output (COP) and the Tricuspid Annular Plane Systolic Excursion (TAPSE) were significantly higher in breastfed infants (5.81 ± 1.01) than CMFF infants (5.26 ± 1.18), (1.56 ± 0.18) and (1.46 ± 0.20) respectively at P < 0.05. Their findings suggested that early feeding patterns in infancy may influence functions and structures of right side of the heart in infancy and that fully breastfeeding supports higher performance and may explain their higher resilience to cardiac insults later in life [21].
This study revealed that not breastfeeding was associated with increased tendency towards obesity. Breastfeeding reduced the odds of overweight or obesity as indicated by many workers [22; 23; 24; 25]. Studies involving autopsies, ultrasounds, and cardiac magnetic resonance imaging (cMRI) have demonstrated that obesity may influence cardiac morphology [26]. One of the most frequently observed alterations is left ventricular (LV) hypertrophy, often eccentric, particularly in the absence of concurrent HTN. Chahal et al. [27] in a study that involved 4127 patients revealed that the right ventricular mass was 15% greater in overweight/obese patients compared to lean patients and right ventricular volumes were 26% larger in overweight/obese subjects compared to lean patients (p < 0.001 for the trend) [27]. A cross-sectional study was conducted for 76 healthy infants aged 3 to 12 months of life (38 breastfed and 38 CMFF, BMI percentiles were significantly higher in CMFF infants compared to breasted infants (P < 0.05). BMI was positively correlated with structural dimensions in CMFF but not breastfed. BMI correlated with RV function in breastfed but not CMF fed infants [28].
This study also indicated that not breastfeeding was associated with EBP. However there is limited evidence that suggests that never versus ever being fed human milk is associated with EBP within a normal range at 6–7 y of age. Moderate evidence suggests there is no association between the duration of any human milk feeding and childhood BP. Limited evidence suggests there is no association between the duration of exclusive human milk feeding and BP or metabolic syndrome in childhood. Additional evidence about intermediate outcomes for the 4 systematic reviews was scant or inconclusive [29]. None the less Metabolic syndrome (MetS) which is defined by a cluster of several cardio-metabolic risk factors, specifically visceral obesity, hypertension, dyslipidemia, and impaired glucose metabolism, were found to increase risks of developing future CVD and type 2 diabetes mellitus (T2D) [30].
On the other hand Doppler findings suggested no relationship between the findings of MVP, TR, ASD or VSD and early feeding, BP or obesity. MVP was the commonest lesion detected in 11 cases (7.3%). MVP is s generally considered a benign condition often associated with a leaky valve causing blood to flop back into the atrium; however, at times, it may present with sudden cardiac death, endocarditis, arrhythmias or cerebrovascular accident. It is more associated with leaness rather than obesity. It ranges from 4–8%. MVP usually occurs as a primary disorder and is commonly, but not invariably, associated with myxomatous proliferation of the mitral valve and chordae tendineae. The absence of any relationship between obesity and even morbid obesity on the progression or complication associated with mitral regurge is in agreement with many other workers who studied MR after reconstructive surgery [31].
In addition MVP in association with EBP was not an issue in this study. Low BP is reported by others as a common feature in patients with MVP, and association between the two entities was found in population-based studies [32]. MVP individuals demonstrate increased beta-adrenergic receptor responsiveness associated with a hyperkinetic circulation [33]. The latter research team showed that in patients with MVP giving propranolol increased BP, and decreased heart rate, and depends, namely, on β1 receptors blockade. Increase in BP is an unusual response to adrenergic beta-blockade in normal conditions, and this finding supports the preponderance of β2 receptors on the BP control in patients with MVP. Breastfeeding through practices as early initiation, cue feeding, night feeding and tactile stimulation may assist in stabilizing the hyper-responsiveness of adrenergic responses preventing the sudden disturbances in BP and HR shown in individuals with MVP. However this may need further investigation. A study conducted in Cairo University Children’s Hospital on infants with CHD and heart failure (HF) showed that breastfeeding and skin-to-skin contact (SSC) resulted in a sustained improvement in their oxygen saturations and vital signs when compared to the artificially fed infants with CHD and HF [34]. Another study in Sweden showed that immediate SSC versus incubator care had beneficial effects on the cardiorespiratory stabilisation of very preterm infants. SSC stimulates oxytocin release in mother and infant which is a hormone and neuropeptide, is associated with calmness, bonding, and stress reduction [35].
Inappropriate foods introduced early in life that include adding sugar and starch to bottles and salt to weaning foods are shown to be linked with higher BP. A study in Egypt showed that high BP prevalence in young school children and youth was associated with adding table salt, regular consumption of certain energy dense foods, and certain types of salty foods and foods with high sodium content (OR 2.6) [36]. In another study snacking, high intakes of sugary beverages and less physical activity among children had a higher risk for HBP (OR 2.5) [37] and especially when children were obese [38; 15] In Qalyuibiya, school-aged children with prehypertension or EBP were 4 times less likely to practice sports [39]. EBP was more prevalent in private than in public schools [38]. EBP was more prevalent in obese versus overweight (22% vs. 6.4%) and WC was reported to be a good indicator of elevated BP [40]. A study conducted for primary school children in Menoufia in Egypt showed that prehypertension was 2.8% in males and 5.2% in females who were overweight and obese and increase in age in both sexes [41].
The risk of EBP has been associated with disturbed lipid metabolism and other biomarkers of CVD. A study by Attia (2017) showed that biomarkers of CVD were higher in non-breastfed children and their mothers who did not breastfeed compared to mothers and children who were exposed to breastfeeding [42]. Obese and hypertensive youth had lipid profiles of atherosclerosis and high-risk patterns of impaired glucose homeostasis (pre-diabetes) and when the research team conducted Doppler studies for these obese youth they found increased risk of diastolic dysfunction [43]. Left ventricular diastolic function (LVDF) is an important marker of early cardiovascular remodelling, which has not been well summarized in young people with overweight/obesity. Increased BMI was associated with worse LVDF in all measures except early mitral inflow deceleration time, with septal early diastolic tissue peak velocity to late diastolic tissue peak velocity ratio having the strongest association (n = 13 studies, 1824 individuals; r = − 0.69; P < 0.001). Elevated HOMA-IR was also associated with worse LVDF [44]. Hence obesity and EBP results in a combination of disturbed metabolism of glycemic homeostasis and renal dysfunction apparently emerging from the young age probably triggered by poor early feeding practices of not breastfeeding and exposure to CMFF.
The study has a number of limitations related to its small size and limited representation, although cases were taken from Damanhur Teaching hospital which is a referral hospital for one of the largest governorates in Egypt, still conclusive findings cannot be made on such a sample. However, it is a definite eye open to the pending holocaust caused by the inappropriate early feeding practices that have invaded the lives and eating behavior of young children. The detection of EBP in this age group and high prevalence of pre-HTN and obesity is a disturbing finding. Moreover CHD, although mild and predominantly encompassing MVP in almost one half of the cases, which is a benign condition, yet could develop into complications if associated with untreated high BMI and EBP on the long run. Breastfeeding is by far the most suitable and safe feeding practice for children and should be promoted and supported in addition with strict laws to regulate salt intake in marketed foods [45]. Regular monitoring of young children for EBP in nurseries, especially among the obese children is recommended. Future studies that examine these findings through demographic surveys are needed not only in Egypt but in other countries in the region. Preventive actions through early detection and campaigns for increasing awareness of the public about the importance of tracking their child’s feeding behavior and checking their BP and physical health status beginning as early as preschool age is recommended.