Trajectory of systolic blood pressure in children and adolescents

A cross-sectional study on the relationship between the risk of hypertension and obesity status among pre-adolescent girls from rural areas of Southeastern region of the United States

This study investigated early indications of hypertension risk and the association of overweight and obesity in young girls from a low socioeconomic region of the rural South. 139 females (M age = 8.85 ± 1.67 years) from a rural school in the Southeastern region of the United States served as participants. Body mass index was calculated based on the child's height and weight measurements (kg/m2) and resting blood pressure measurements were taken with calibrated, automatic oscillations devices. Girls who were overweight or obese were 2.81 times more likely to have a systolic blood pressure indicative of being at-risk/hypertensive (i.e., pre-hypertension and/or hypertension stage 1) than girls who were not overweight/obese. In fact, the percentage of overweight/obese girls who were at-risk/hypertensive was double that of girls who were not overweight/obese (43.2% versus 21.3%), respectively. Being overweight or obese is associated with almost three times a higher risk of hypertension than girls who are not overweight or obese.

Sex-specific trajectories of systolic and diastolic blood pressure in youth

BACKGROUND AND OBJECTIVE

High blood pressure early in life is associated with cardiovascular disease morbidity and mortality in adulthood. The objective was to identify sex-specific trajectories of SBP and DBP from early adolescence to early adulthood and to assess the impact of modifiable factors on the trajectories, including BMI, smoking, alcohol use, physical activity, and screen-time.

METHODS

Data were drawn from four waves of a prospective investigation of 1294 youth aged 12-13 years at inception and followed until age 24 years. Group-based trajectory models were used to identify trajectories and assess the impact of modifiable factors in 403 men and 432 women.

RESULTS

Three SBP trajectories were identified in men [corresponding to low (43.2%), medium (45.2%), and high SBP (11.7%)] and women [corresponding to low (48.1%), medium (44.7%), and high SBP (7.2%)]. Similar results were observed for DBP in both sexes. BMI and smoking were associated with higher SBP and DBP values in most trajectory groups, whereas screen-time in both sexes and physical activity in women were associated with high SBP trajectories only.

CONCLUSION

There is heterogeneity in the sex-specific natural course of SBP and DBP in youth and in the magnitude of the effect of modifiable factors on SBP and DBP across trajectories. Distinguishing trajectories allows identification of subgroups at risk of hypertension and cardiovascular disease later in life and in addition can inform the design of targeted interventions to attenuate high SBP and DBP trajectories over time and maintain normal trajectories.

Association Between Early Life Growth and Blood Pressure Trajectories in Black South African Children

Early growth is associated with blood pressure measured on one occasion, but whether early life growth patterns are associated with longitudinal blood pressure trajectories is under-researched. Therefore, we sought to examine the association between early growth and blood pressure trajectories from childhood to adulthood. Blood pressure was measured on 7 occasions between ages 5 and 18 years in the Birth to Twenty cohort study, and conditional variables for growth in infancy and mid-childhood were computed from anthropometric measures (n=1937, 52% girls). We used a group-based trajectory modeling approach to identify distinct height-adjusted blood pressure trajectories and then tested their association with growth between birth and mid-childhood adjusting for several covariates. Three trajectory groups were identified for systolic and diastolic blood pressure: lower, middle, and upper in boys and girls, separately. In boys, predictors of the middle or upper systolic blood pressure trajectories versus the lower trajectory were in birth weight (odds ratio 0.75 [95% confidence interval 0.58-0.96] per SD) and relative weight gain in infancy (4.11 [1.25-13.51] per SD). In girls, greater relative weight gain and linear growth in both infancy and mid-childhood were consistently associated with an almost 2-fold higher likelihood of being in the upper versus lower systolic blood pressure trajectory. The associations for the diastolic blood pressure trajectories were inconsistent. These findings emphasize the importance of identifying children at risk of progression to high blood pressure. Accelerated growth in infancy and mid-childhood may be a key target for early life intervention in prevention of elevated blood pressure progression.

Epidemiological studies on noise and blood pressure in children: Observations and suggestions

OBJECTIVE

The goal of this review was to investigate methodological differences in studies on the effects of aircraft or road-traffic noise on blood pressure (BP) of urban children, emphasizing the similarities and differences in blood pressure measurements.

METHODS

A literature search has identified eight peer-reviewed studies, four conference proceedings and one PhD thesis on the effects of aircraft or road-traffic noise on children's blood pressure published in English in the last 30 years. Most of the studies were cross-sectional, and four studies were longitudinal, with follow-up period from one to three years. The studies were analyzed according to the following methodological issues: study design, children's characteristics, noise exposure assessment and blood pressure measurements. The effects of noise on systolic and diastolic pressure were presented in detail.

RESULTS

Studies on aircraft noise had more uniform methodology, indicating a slight tendency towards a positive relationship between aircraft noise exposure and BP in children. The studies on road-traffic noise were methodologically diverse, but compared to aircraft noise studies they showed a more uniform trend in the direction of a positive relationship with systolic BP. The time, place and number of BP measurements, as well as the devices and cuff sizes varied among the studies. Children's age, gender, body composition and ethnicity, and socio-economic status remain the greatest source of diversity in BP values.

CONCLUSIONS

The reviewed studies were methodologically diverse concerning noise exposure assessment, BP measurement, study design and control for confounders. In spite of this, they indicate a tendency toward positive association between noise exposure and children's blood pressure. We recommended strategies that might help researchers adopt similar procedures when measuring BP in future field studies.

Blood pressure trajectories prior to death in patients with diabetes

OBJECTIVE

The goals of this study were to examine trajectories of blood pressure (BP) in adults with diabetes and investigate the association of trajectory patterns with mortality.

RESEARCH DESIGN AND METHODS

A nonconcurrent longitudinal design was used to monitor 3,766 Medicare patients with diabetes from 2005 through 2008. Data were extracted from a registry of Medicare beneficiaries, which was developed by a large academic practice that participated in the Physician Group Practice Medicare Demonstration. The relationship between BP trajectories and all-cause mortality was modeled using multilevel mixed-effects linear regression.

RESULTS

During the 4-year study period, 10.7% of the patients died, half of whom were aged≥75 years. The crude and adjusted models both showed a greater decline in systolic and diastolic BP in patients who died than in those who did not die. In a model adjusted for age, sex, race, medications, and comorbidities, the mean systolic BP decreased by 3.2 mmHg/year (P<0.001) in the years before death and by 0.7 mmHg/year (P<0.001) in those who did not die (P<0.001 for the difference in slopes). Similarly, diastolic BP declined by 1.3 mmHg/year for those who died (P<0.001) and by 0.6 mmHg/year for those who did not die (P<0.001); the difference in slopes was significant (P=0.021).

CONCLUSIONS

Systolic and diastolic BP both declined more rapidly in the 4 years before death than in patients who remained alive.

Relationship between BMI and blood pressure in girls and boys

Aim

To investigate the relationship between BMI and blood pressure as this is of crucial interest in evaluating both public health and the clinical impact of the so-called obesity epidemic.

Methods

Data were gathered from 1899 children aged between 6 and 14 years, analysing and evaluating a possible relationship between BMI and systolic and diastolic blood pressure values for both girls and boys. Each child was classified on the basis of age- and sex-specific BMI percentile as normal weight (<85th percentile), overweight (≥85th and <95th percentile) or obese (≥95th percentile).

Results

In comparisons among age–sex–BMI percentile groups, systolic and diastolic blood pressure values were higher in obese and overweight groups than in normal weight groups for both sexes. Although BMI among girls was higher than among boys in all three percentile groups, there were no significant differences between sexes with respect to blood pressure values.

Conclusion

The present findings emphasize the importance of the prevention of obesity in order to prevent future related problems such as hypertension in children and adolescents.