Table 2. Main results from the studies included in the systematic review.
| Author | Mean BW | Source of BW data | Mean BP (mm Hg) | Procedure for BP measurement | Relationship between BW and BP | Adjusting factors |
|---|---|---|---|---|---|---|
| Ayoola | 2.9 kg | Hospital birth records | SBP=71.0 DBP=36.1 |
With the child comfortable on the mother’s lap for five minutes or asleep, three BP measurements with a minute’s interval between successive measurements were taken on the left arm using a Datascope monitor. Mean of the last two readings was used for analysis. | Positive BW-BP association. SBP increased by 8.35 mmHg per Kg increase in BW (95% CI: 4.36, 12.35, p<0.001). DBP increased by 3.07mmHg per Kg increase in BW (95% CI: 0.26, 5.88, p=0.032) | Gestational age, baby length, maternal malaria, age, weight, height, BP, gravidity, antenatal visits |
| Chiolero | 3.1 kg | Medical records | Could not be determined | After five minutes’ rest, two BP measurements were taken on the right arm with a minute’s interval between each using automated devices (OmronM5; Omron). Mean of the two measurements was used for analysis. | No overall BW-BP association. BW was not associated with SBP or with DBP, with exception of girls at 12.5 years among whom BW was inversely associated with SBP (β=0.9, 95% CI: -1.6, -0.1, p=0.026) and DBP (β=-0.7, 95% CI: -1.3, -0.1, p=0.028) | Current weight |
| Hawkesworth | 2.9 kg | Birth records | SBP=110.5 DBP=64.7 |
Measured in triplicate using the automated Omron 7051T device (Omron, UK), following manufacturer’s instruction. Mean of the three measurements was used for analysis | No association between BW and BP, β=-0.001, 95% CI: -0.002, 0.000, P=0.06 | Age, current body size, sex, gestational age, birth season, |
| Longo-Mbenza | 2.4 kg | Parental recall, medical records | Could not be determined | With child in a sitting position and relaxed for 20 minutes, five BP measurements were obtained using an automatic device (HEM-705 CP; Omron, Tokyo, Japan). Not clear which measurements were used in the analysis | BW inversely correlated with BP. With r=-0.1, p<0.001 for SBP and r=-0.1, p<0.05 for DBP. LBW had twice the odds of hypertension OR=2.0, 95% CI: 0.9, 8.2, p<0.01 for SBP and OR=2.3, 95% CI: 0.6, -11.5, p<0.01 for DBP1 | NM |
| Margetts | 3.0 kg | Birth records | 1 year: SBP= 89.3 DBP= 56.2, 9 years: SBP=102.7 DBP=63.9 |
After five minutes in a sitting position or on the mother’s knee in the young children, BP was measured twice on the right arm using an automated device (Dinamap model: 18465X). Not clear which measurements were used in the analysis | BW not associated with SBP at any age | NM |
| Sadoh | 3.2 kg | Hospital birth records | SBP=69.2 | Measured one hour after feeds between 11:00 and 13:30 using a Dinamap 8100 monitor (Critikon, Tampa Fla) device, when the baby was asleep or awake and calm. Three BP measurements were obtained within three minutes of each other on the right arm. Mean of three BP readings was used in the analysis | Positive BW-BP association BW was correlated with SBP (r=0.235, p=0.001), SBP rose by 3.61 mmHg per 0.5 kg increase in birth weight | NM |
| Salvi | 3.4 kg | Obstetric records in local hospitals | SBP=118.1 DBP=69.9 |
Three BP measurements with 3 minutes’ interval between successive measurements were taken on the left arm, after 10 minutes’ rest in a sitting position. An automated oscillmetric device (Omron 705T; Omron, Kyoto Japan) was used. Average of the three measurements was used for the analysis | No correlation between BW and SBP | Multivariate analysis was not done |
| Law | 3.2 kg | Birth records | SBP=101.6 | After five minutes’ rest, three BP measurements were taken on the left arm using automated BP machines (Dinamap model 8100) with a one-minute interval between consecutive measurements. Mean of the three measurements was used for the analysis | No association between BW and SBP (β=0.4, 95% CI: -2.1, 2.9) | Gender, observer, child's status, (crying or not) current weight and cuff size. |
| Woelk | 3.0 kg | Birth records | SBP=108.3 DBP= 62.1 |
With child sitting quietly, BP was measured in the morning on the right arm. Three measurements were taken two minutes apart using a Dinamap model 8100 BP. The average of the last two BP readings was used for analysis | Inverse relationship between BW and SBP. SBP rose by 1.73 mmHg per kg decrease in BW (95% CI: 0.18, 3.28), P=0.0286. No association between BW and DBP (β=-1.06, 95% CI: -2.57, 0.45) | Current weight |
| Silva | 3.2 kg | - | SBP=102 DBP=62 |
After resting for 5-10 minutes in a sitting position, three consecutive BP measurements were taken on the left arm with a two minutes’ interval using an automatic sphygmomanometer (OMRON, model HEM-742, Nanjing, Chine). Mean of last two readings was used for analysis. | No correlation between BW and SBP, r=-0.016, weak correction between DBP and BW r=0.09, p <0.05. Categorising birth weight into 4 groups, no association between birth weight category and SBP (p=0.991) or DBP (p=0.059). | NM |
| Nwokoye2 | 2.5-4.0 kg | Hospital birth records | Day 1, SBP=63.3 DBP=36.8 Day 2, SBP=65.6 DBP=40.0 |
After 10-15 minutes’ rest, a single BP measurement was taken on the right arm when the infant was awake and quiet or asleep and in spine position using an oscillometic machine (Dinamap 8100) |
Positive correlation between BW and SBP, r=0.37, p<0.01 between 0-24 hours and r=0.29, p<0.01 between 25-48 hours. No correlation between BW and DBP |
NM |
| Youmbissi | 3.2 kg | Hospital birth records | SBP=65.1 | Measured in the morning, on the right arm of a quiet and awake child. Three measurements were taken using a zero sphygmomanometer. Average of the three measurements used for the analysis | No association between BW and SBP, r=0.12 | NM |
| Levitt* | 3.1 kg | Birth records | SBP=108.0 DBP=62.6 |
After 10 minutes’ rest, BP was measured in triplicate using a Dinamap vital signs Monitor (1846SX). The lowest DBP with its matching SBP were used in the analysis |
Inverse association between BW and SBP (r=-0.05, p<0.001), SBP fell by 3.4mmHg, (95% CI: 1.4, 5.3) per kg increase in BW. No association between BW and DBP |
Current weight and height |
| Kagura* | 3.1 kg | Birth records | Could not be determined | After five minutes’ rest, BP was measured in triplicate with two-minute intervals between successive measurements, using the Dinamap Signs monitor 1846SX (Critikon) at 5 years and Omron M6 (Omron, Kyoto, Japan) at 8 to 18 years. Not clear which measurements were used in the analysis | Inverse association between BW and middle BP trajectory among boys (OR=0.75, 95% CI: 0.58, 0.96, p=0.0223). No other associations seen | Height, SES, maternal age, parity and gestational age |
| Griffiths* | 3.1 kg | Birth records | SBP=114.8 | In participants in a sitting position, three measurements were taken using a digital (Omron M6; Omron Kyoto, Japan) device with a rest of several minutes between successive measurements. The average of the last two measurements was used for analysis |
Inverse association between BW and SBP among boys (β=-0.003, p<0.1). No association between BW and SBP among girls |
Current height |
| Adair* | 3.1 kg | Hospital birth records | SBP=117.5 DBP=71.4 |
After 5-10 minutes’ rest, three BP measurements were taken using a digital device (Omron M6). The average of the last two measurements was used for analysis | No association between BW and BP. For SBP β= 0.05, 95% CI: -.79, 0.90 in males and 0.08 (-0.69, 0.84) in females, and for DBP β=-0.05 (-0.78, 0.68) among males and 0.17 (-0.51, 0.85) in females | NM |
*
Papers from the same study group (Birth to twenty cohort)
BW; birth weight, BP; blood pressure, SES; Socioeconomic status, NM; Not mentioned, r; correlation coefficient, β: linear regression coefficient, OR; Odds ratio, CI; Confidence interval
1
95% CI and p-value reported as in paper but are inconsistent
2
Mean birth weight not reported and could not be calculated (determined)