The relationship between body mass index and mid-arm circumference in a pregnant population

The Mid-Upper Arm Circumference as a Substitute for Body Mass Index in the Assessment of Nutritional Status among Pregnant Women: A Cross-Sectional Study

To compare mid-upper arm circumference (MUAC) with body mass index (BMI) and propose MUAC cut-off points corresponding to BMIs of <18.5 kg/m² (underweight) and ≥30.0 kg/m² (obesity) for pregnant Sudanese women, a cross-sectional community-based study was conducted in the city of New Halfa, Sudan. Healthy pregnant women were recruited. Body parameters such as height, weight, and MUAC were measured. The MUAC (cm) cut-off values for underweight and obesity were determined using receiver operating characteristic (ROC) curve analysis. Of 688 pregnant women, 437 were in early pregnancy (<20 weeks of gestation) and 251 were in late pregnancy (≥20 weeks of gestation). There was a significant positive correlation between BMI and MUAC among women in both early pregnancy (r = 0.734) and late pregnancy (r = 0.703). The cut-off points of MUAC for detecting underweight and obesity were found to be 24.0 cm and 29.0 cm, respectively, for women in early pregnancy, with good predictive values. For women in late pregnancy, the cut-off points for detecting underweight and obesity were 23.0 cm and 28.0 cm, respectively. We concluded that for Sudanese pregnant women, the MUAC cut-off points identified in the study for diagnosing underweight and obesity are both sensitive and specific.

Correlation of patient characteristics with arm and finger measurements in Asian parturients: a preliminary study

Background

Accurate blood pressure (BP) measurement depends on appropriate cuff size and shape in relation to the arm. Arm dimensions outside the recommended range of cuff sizes or trunco-conical arms may result in inaccurate BP measurements. Measuring BP using finger cuffs is a potential solution. Arm cuff size is based on mid-arm circumference (MAC), and trunco-conicity is quantified by conicity index. We aimed to determine the correlation of MAC, body mass index (BMI), and weight with conicity index.

Methods

A prospective cohort study was conducted in the KK Women’s and Children’s Hospital where third trimester parturients scheduled for cesarean delivery were recruited after obtaining informed consent. Parturients were asked to rate their experience with time taken to obtain BP readings, cuff popping off during measurement, need to move the cuff from the upper arm to lower arm or leg, and need to change to a different cuff. Our primary outcome was the correlation between MAC and conicity index, calculated using Pearson’s correlation. The correlation between BMI and weight with conicity index was also determined.

Results

We enrolled 300 parturients. Moderate correlation was found between left MAC and left conicity index (r = 0.41, 95% CI 0.32 to 0.51), and right MAC and right conicity index (r = 0.39, 95% CI 0.29 to 0.48). Weight (r = 0.35 to 0.39) and BMI (r = 0.41 to 0.43) correlated with conicity index in this study. MAC of 1 parturient fell outside the recommended range for arm cuffs, but all parturients fit into available finger cuffs. Obese parturients had increased problems with arm cuffs popping off and needing a change of cuff.

Conclusions

BMI better correlated with conicity index compared to MAC or weight. Standard finger cuffs were suitable for all parturients studied and may be a suitable alternative.

Trial registration

Clinicaltrials.gov NCT04012151. Registered 9 Jul 2019

Determinants of low birth weight in the context of maternal nutrition education in urban informal settlements, Kenya

Inadequate knowledge in maternal nutrition is one of the determinants of low birth weight. However, little evidence is available on whether maternal nutrition counselling alone can influence birth weight among women from low socioeconomic households. This study assessed the effect of prenatal maternal nutritional counselling on birth weight and examined the related risk factors. A cluster randomized controlled trial was conducted to assess the effectiveness of home-based maternal nutritional counselling on nutritional outcomes, morbidity, breastfeeding, and infant feeding practices by the African Population and Health Research Center in two urban informal settlements of Nairobi. The intervention group received monthly antenatal and nutritional counselling from trained community health volunteers; meanwhile, the control group received routine antenatal care. A total of 1001 participants were included for analysis. Logistic regression was applied to determine associations between low birth weight and maternal characteristics. A higher prevalence of low birth weight was observed in the control group (6.7%) than in the intervention group (2.5%; P&lt;0.001). Logistic regression identified significant associations between birth weight and intervention group (adjusted odds ratio (AOR)=0.26; 95% confidence interval (CI), 0.10-0.64); maternal height &lt;154.5 cm (AOR=3.33; 95% CI, 1.01-10.96); last antenatal care visits at 1st or 2nd trimesters (AOR=9.48; 95% CI, 3.72-24.15); pre-term delivery (AOR=3.93; 95% CI, 1.93-7.98); maternal mid-upper arm circumference &lt;23 cm (AOR=2.57; 95% CI, 1.15-5.78); and cesarean delivery (AOR=2.27; 95% CI, 1.04-4.94). Nutrition counselling during pregnancy reduced low birth weight and preterm births, which was determined by women of short stature, early stoppage of antenatal visit, and cesarean delivery.

Influence of body mass index on the outcome of brachial plexus surgery: are there any differences between elbow and shoulder results?

BACKGROUND

Body mass index (BMI) has recently been identified as a predictor of outcomes following reconstructive surgery of shoulder palsies. In this study, we sought to determine if the same holds true for the reconstruction of elbow flexion.

METHODS

Forty patients who had undergone partial ulnar-to-biceps nerve transfer (Oberlin's procedure) for shoulder palsy were assessed and compared against 18 previously reported patients who had undergone reconstruction for elbow palsies. The British Medical Research Council (BMRC) scale and an index dividing shoulder abduction strength in the affected arm by healthy arm were recorded. All patients had undergone surgery within 12 months of injury and had ≥ 12 months of follow-up.

RESULTS

M4 or M3 biceps strength was obtained in 90 % of patients. Final strength on the affected side averaged 5.8 kg, versus 20.2 kg on the normal side, for a mean recovery index score of 0.30. In this sample of 40 patients, BMI did not predict percentage strength or BMRC grade recovery. Neither did age, number of roots involved, the affected side, nor time to surgery. Comparing patients with elbow versus shoulder reconstruction, there were no differences, except that patients undergoing Oberlin's procedure had a statistically longer duration of time between injury and surgical repair (7.4 vs 5.1 months, p < 0.006).

CONCLUSIONS

Our data suggest that proximal muscle re-innervation is functionally more dependent upon BMI than distal re-innervation, likely because proximal muscles must support the weight of the entire extremity, while more distal muscles do not. BMI should be taken into consideration when planning surgery.

Spinal to accessory nerve transfer in traumatic brachial plexus palsy: is body mass index a predictor of outcome?

INTRODUCTION

Several factors that affect functional recovery after surgery in severe brachial plexus lesions have been identified, i.e., time to surgery and presence of root avulsions. The body mass index (BMI) of the patient could be one of these possible factors. The objective of the present paper is to systematically study the relationship between BMI and the outcome of abduction following spinal accessory to suprascapular nerve transfer.

METHODS

We retrospectively studied 18 cases that followed these inclusion criteria: (1) Male patients with a spinal accessory to suprascapular nerve transfer as the only procedure for shoulder function reanimation; (2) at least C5-C6 root avulsion; (3) interval between trauma and surgery less than 12 months; (4) follow-up was at least 2 years; (5) no concomitant injury of the shoulder girdle. Pearson correlation analysis and linear regression was performed for BMI versus shoulder abduction.

RESULTS

The mean range of post-operative abduction obtained across the entire series was 49.7° (SD ± 30.2). Statistical evaluation revealed a significant, negative moderately strong correlation between BMI and post-operative range of shoulder abduction (r = -0.48, p = 0.04). Upon simple linear regression, time to surgery (p = 0.04) was the only statistically significant predictor of abduction range negatively correlated.

CONCLUSIONS

Analysis of this series suggests that a high BMI of patients undergoing brachial plexus surgery is a negative predictor of outcome, albeit less important than others like time from trauma to surgery. Nevertheless, the BMI of patients should be taken into consideration when planning surgical strategies for reconstruction.