Analysis of neonatal mortality risk factors in Brazil: a systematic review and meta-analysis of observational studies

OBJECTIVE

To identify, using a systematic review and meta-analysis of observational studies, which risk factors are significantly associated with neonatal mortality in Brazil, and to build a comprehensive national analysis on neonatal mortality.

SOURCES

This review included observational studies on neonatal mortality, performed between 2000 and 2018 in Brazilian cities. The MEDLINE, Elsevier, Cochrane, LILACS, SciELO, and OpenGrey databases were used. For the qualitative analysis, the Newcastle-Ottawa Scale was used. For the quantitative analysis, the natural logarithms of the risk measures and their confidence intervals were used, as well as the DerSimonian and Laird method as a random effects model, and the Mantel-Haenszel model for heterogeneity estimation. A confidence level of 95% was considered.

SUMMARY OF FINDINGS

The qualitative analysis resulted in six studies of low and four studies of intermediate-low bias risk. The following exposure factors were significant: absence of partner, maternal age ≥35 years, male gender, multiple gestation, inadequate and absent prenatal care, presence of complications during pregnancy, congenital malformation in the assessed pregnancy, Apgar<7 at the fifth minute, low and very low birth weight, gestational age≤37 weeks, and caesarean delivery.

CONCLUSION

The most significant risk factors presented in this study are modifiable, allowing aiming at a real reduction in neonatal deaths, which remain high in the country.

Oral antioxidant therapy for prevention and treatment of preeclampsia: Meta-analysis of randomized controlled trials

AIMS

To determine whether oral antioxidant therapies, of various types and doses, are able to prevent or treat women with preeclampsia.

DATA SYNTHESIS

The following databases were searched: MEDLINE, CENTRAL, LILACS, and Web of Science. Inclusion criteria were: a) randomized clinical trials; b) oral antioxidant supplementation; c) study in pregnant women; d) control group, treated or not with placebo. Papers were excluded if they evaluated antioxidant nutrient supplementation associated with other non-antioxidant therapies. Data were extracted and the risk of bias of each study was assessed. Heterogeneity was analyzed using the Cochran Q test, and I2 statistics and pre-specified sensitivity analyses were performed. Meta-analyses were conducted on prevention and treatment studies, separately. The primary outcome was the incidence of preeclampsia in prevention trials, and of perinatal death in treatment trials. Twenty-nine studies were included in the analysis, 19 for prevention and 10 for treatment. The antioxidants used in these studies were vitamins C and E, selenium, l-arginine, allicin, lycopene and coenzyme Q10, none of which showed beneficial effects on the prevention of preeclampsia (RR: 0.89, CI 95%: [0.79-1.02], P = 0.09; I² = 39%, P = 0.04) and other outcomes. The antioxidants used in the treatment studies were vitamins C and E, N-acetylcysteine, l-arginine, and resveratrol. A beneficial effect was found in intrauterine growth restriction.

CONCLUSIONS

Antioxidant therapy had no effects in the prevention of preeclampsia but did show beneficial effects in intrauterine growth restriction, when used in the treatment of this condition.

Effects of iron supplementation versus dietary iron on the nutritional iron status: Systematic review with meta-analysis of randomized controlled trials

This meta-analysis compared the effects of dietary intervention versus iron supplementation on biochemical parameters related to the iron nutritional status in humans. The PubMed, CENTRAL, LILACS, SCIELO, OPENGREY.EU and ClinicalTrials.gov databases were searched for randomized clinical trials that assigned individuals to a dietary intervention or to an iron supplementation regimen, for 12 weeks or more. The primary outcome was the hemoglobin concentration, and secondary outcomes were ferritin, RDW, mean corpuscular volume, soluble transferrin receptor, total iron binding capacity, serum iron, and transferrin saturation. From the 6095 records identified, twelve studies were included, six with children, five with adolescents/adults, and one with pregnant women. In the subgroup of studies that included anemic/iron deficient children, supplementation significantly increased the hemoglobin concentration (weighted mean difference (WMD): 3.19 g/L [95% CI: 1.31, 5.07]) and induced a significantly greater reduction of the soluble transferrin receptor (WMD: -0.46 mg/L [95% CI: -0.70, -0, 21]), when compared to dietary intervention. It also induced a greater reduction of the total binding capacity of iron in adolescents/adults (WMD: -6.96 μmol/L [95% CI: -12.70, -1.21]). Supplementation showed a better effect on hemoglobin recovery in anemic/iron deficient children, while no differences were observed between supplementation and dietary intervention in treating adolescents/adults.

Association between blood cholesterol and sodium intake in hypertensive women with excess weight

Restricted sodium intake has been recommended for more than 1 century for the treatment of hypertension. However, restriction seems to increase blood cholesterol. In women with excess weight, blood cholesterol may increase even more because of insulin resistance and the high lipolytic activity of adipose tissue.The aim of this study was to assess the association between blood cholesterol and sodium intake in hypertensive women with and without excess weight.This was a cross-sectional study with hypertensive and nondiabetic women aged 20 to 59 years, recruited at the primary healthcare units of Maceio, Alagoas, Brazilian Northeast. Excess weight was defined as body mass index (BMI) ≥25.0 kg/m. Sodium intake was estimated by the 24-hour urinary excretion of sodium. Blood cholesterol was the primary outcome investigated by this study, and its relationship with sodium intake and other variables was assessed by Pearson correlation and multivariate linear regression using a significance level of 5%.This study included 165 hypertensive women. Of these, 135 (81.8%) were with excess weight. The mean sodium intake was 3.7 g (±1.9) and 3.4 g (±2.4) in hypertensive women with and without excess weight, respectively. The multiple normal linear regression models fitted to the "blood cholesterol" in the 2 groups reveal that for the group of hypertensive women without excess weight only 1 independent variable "age" is statistically significant to explain the variability of the blood cholesterol levels. However, for the group of hypertensive women with excess weight, 2 independent variables, age and sodium intake, can statistically explain variations of the blood cholesterol levels.Blood cholesterol is statistically inversely related to sodium intake for hypertensive women with excess weight, but it is not statistically related to sodium intake for hypertensive women without excess weight.

Consumption of minimally processed food is inversely associated with excess weight in adolescents living in an underdeveloped city

BACKGROUND

The consumption of ultra-processed foods may be associated with the development of chronic diseases, both in adults and in children/adolescents. This consumption is growing worldwide, especially in low and middle-income countries. Nevertheless, its magnitude in small, poor cities from the countryside is not well characterized, especially in adolescents. This study aimed to assess the consumption of minimally processed, processed and ultra-processed foods by adolescents from a poor Brazilian city and to determine if it was associated with excess weight, high waist circumference and high blood pressure.

METHODS

Cross-sectional study, conducted at a public federal school that offers technical education together with high school, located in the city of Murici. Adolescents of both sexes and aged between 14-19 years old were included. Anthropometric characteristics (weight, height, waist circumference), blood pressure, and dietary intake data were assessed. Associations were calculated using Poisson regression models, adjusted by sex and age.

RESULTS

At total, 249 adolescents were included, being 55.8% girls, with a mean age of 16 years-old. The consumption of minimally processed foods was inversely associated with excess weight (Adjusted Prevalence Ratio: 0.61, 95% Confidence Interval: [0.39-0.96], P = 0.03). Although the consumption of ultra-processed foods was not associated with excess weight, high blood pressure and high waist circumference, 46.2% of the sample reported eating these products more than weekly.

CONCLUSION

Consumption of minimally processed food is inversely associated with excess weight in adolescents. Investments in nutritional education aiming the prevention of chronic diseases associated with the consumption of these foods are necessary.

COGNITIVE PERFORMANCE OF STUNTED PRE-SCHOOL CHILDREN UNDERGOING NUTRITIONAL RECOVERY TREATMENT

OBJECTIVE

To determine if the treatment of stunted children offered at a specialized center influences their cognitive performance.

METHODS

Two groups of children from vulnerable families were selected, one consisting of stunted children being treated at the Nutrition Education and Recovery Center (CREN), and the other group of eutrophic children from a local, public day care center. At CREN, children are treated in a day-hospital system (9 hours/day, 5 days/week), receiving medical, nutritional and psycho-pedagogical support. All children were submitted to the Denver-II Development Screening Test and had their development and the height-for-age index assessed at 3 moments: at the beginning of the follow-up, and after 6 and 12 months. The socioeconomic status, according to the Brazilian Economic Classification Criteria, was assessed at the beginning of the follow-up. Data were treated by prevalence ratios for cross-sectional baseline analysis, using the Poisson regression, and by pooled prevalence ratios for longitudinal analysis, using a generalized equation estimation model, both adjusted by age, sex and economic status.

RESULTS

Seventy-four children were included, 37 for each group. There were no differences in age, sex and socioeconomic status between groups. In the longitudinal analysis, the CREN group showed better performance in the personal-social domain (pooled prevalence ratio: 0.89; 95% confidence interval - 95%IC 0.82-0.95), with no differences in the other domains.

CONCLUSIONS

The treatment offered at CREN satisfactorily improved the social skills of the treated children, without changing other domains.

Effect of antioxidant supplementation on the auditory threshold in sensorineural hearing loss: a meta-analysis

INTRODUCTION

Hearing loss is conceptualized as any impairment of the ability to hear and/or detect speech or environment sounds, regardless of cause, type, or degree. It may occur at different stages of life; during pregnancy or childbirth, in childhood, adulthood or old age. It should be noted that aging is the most common cause of sensorineural hearing loss followed by noise-induced hearing loss, and both are closely related to the formation of reactive oxygen species. Dietary antioxidant supplementation has been employed as a therapeutic strategy to prevent and/or delay the risks of major human diseases.

OBJECTIVE

To assess randomized clinical trials to determine the effect of antioxidant supplementation on the auditory thresholds in patients of different age groups with sensorineural hearing loss.

METHODS

This systematic review consisted of a search in the following databases: MEDLINE, CENTRAL, ScienceDirect, Scopus, Web of Science, LILACS, SciELO and ClinicalTrials.gov. Additionally, the gray literature was also searched. The search strategy included terms related to the intervention (antioxidant supplementation), primary outcome (sensorineural hearing loss), as well as terms related to randomized clinical trials to improve search sensitivity.

RESULTS

Based on 977 potentially relevant records identified through the search in the databases, ten full-text publications were retrieved for further evaluation. The increase in threshold at the 4kHz frequency was statistically higher in the control group (1.89 [1.01-2.78], p<0.0001) when compared to the NAC group and the ginseng group, whereas at 6kHz, the threshold increase was higher in the control group (1.42 [-1.14-3.97], p=0.28), but no statistically significant differences were found between groups.

CONCLUSION

Ginseng was the antioxidant agent that showed the best effect in preventing auditory threshold worsening at the frequency of 4kHz, but not at 6kHz in patients with sensorineural hearing loss caused by exposure to high sound pressure levels. There was no improvement in the thresholds with vitamin E supplementation.

Aging and wave-component latency delays in oVEMP and cVEMP: a systematic review with meta-analysis

INTRODUCTION

The natural aging process may result in morphological changes in the vestibular system and in the afferent neural pathway, including loss of hair cells, decreased numbers of vestibular nerve cells, and loss of neurons in the vestibular nucleus. Thus, with advancing age, there should be a decrease in amplitudes and an increase in latencies of the vestibular evoked myogenic potentials, especially the prolongation of p13 latency. Moreover, many investigations have found no significant differences in latencies with advancing age.

OBJECTIVE

To determine if there are significant differences in the latencies of cervical and ocular evoked myogenic potentials between elderly and adult patients.

METHODS

This is a systematic review with meta-analysis of observational studies, comparing the differences of these parameters between elderly and young adults, without language or date restrictions, in the following databases: Pubmed, ScienceDirect, SCOPUS, Web of Science, SciELO and LILACS, in addition to the gray literature databases: OpenGrey.eu and DissOnline, as well as Research Gate.

RESULTS

The n1 oVEMP latencies had a mean delay in the elderly of 2.32ms with 95% CI of 0.55-4.10ms. The overall effect test showed p=0.01, disclosing that such difference was significant. The heterogeneity found was I²=96% (p<0.001). Evaluation of p1 latency was not possible due to the low number of articles selected for this condition. cVEMP analysis was performed in 13 articles. For the p13 component, the mean latency delay in the elderly was 1.34ms with 95% CI of 0.56-2.11ms. The overall effect test showed a p<0.001, with heterogeneity value I²=92% (p<0.001). For the n23 component, the mean latency delay for the elderly was 2.82ms with 95% CI of 0.33-5.30ms. The overall effect test showed p=0.03. The heterogeneity found was I²=99% (p<0.001).

CONCLUSION

The latency of oVEMP n1 wave component and latencies of cVEMP p13 and n23 wave components are longer in the elderly aged >60 years than in young adults.

Higher central fat and poor self-body image in short-stature overweight/obese women living in Brazilian shantytowns

Background

Short stature in adult life, a possible consequence of poor perinatal conditions, is associated with higher risk of mortality and social disabilities. We aimed to determine whether low-income, overweight/obese, short-stature (SS) women show alterations in body composition, self-body-image perception, and biochemical profile compared to their non-short (NS) counterparts.

Methods

A cross-sectional study was conducted with women living in shantytowns and mother or relatives to undernourished children treated in a center for recuperation and nutritional education. Inclusion criteria were: (1) age, 19–45 years; (2) stature < 152.3 cm or > 158.7 cm; and (3) body mass index > 25 kg/m². Socioeconomic, anthropometric, biochemical, and body image data were collected. We analyzed 56 SS and 57 NS women.

Results

The SS group showed a higher waist-to-height ratio (WHtR) (mean: 0.63; standard deviation: 0.06 for SS and mean: 0.60; standard deviation: 0.07 for the NS group; p = 0.02), and, in the adjusted analysis, showed lower fat-free mass (Estimated Marginal Mean for the SS group: 45.7 kg 95% confidence intervals (CI) (45.2–46.2) and for the NS group: 46.9 kg 95% CI (46.4–47.4); p < 0.01) and higher fat mass (Estimated Marginal Mean for the SS group: 32.5 95% CI (31.9–33.0) and for the NS group: 31.4 kg 95% CI (30.9–31.9); p < 0.01). Body mass index was a better predictor of current self-body-image perception for NS women. The SS coefficient values were β = 0.141, SE = 0.059, and R²-Nagelkerke = 0.107, and the NS coefficients values were β = 0.307, SE = 0.058, and R²-Nagelkerke = 0.491 (Z = 2.006; p < 0.05). Considering the obese subgroup, six out of 32 (18.8%) SS women and 14 out of 33 (42.4%) NS women perceived themselves as obese (χ² = 4.27; p = 0.03). This difference remained significant even after adjustment by age, schooling, and number of children (p = 0.04). Only the total thyroxin showed significant differences between groups, lower in SS women (p = 0.04).

Discussion

Overweight/obese, low-income SS women have more central adiposity and impaired self-body image perception, and the body mass index is a weaker predictor of it, compared to NS women. Misperception about body size may be linked with an overestimation of health and underestimation of risk, which may lead to a lower utilization of the health care system and inadequate physician counseling. These features may account, at least partially, for the higher mortality risk seen in SS adults.

Energy Intake in Socially Vulnerable Women Living in Brazil: Assessment of the Accuracy of Two Methods of Dietary Intake Recording Using Doubly Labeled Water

BACKGROUND

Diet is related to the prevention of chronic diseases, but assessing dietary intake is a complex task, especially in socially vulnerable populations.

OBJECTIVES

To assess the accuracy of the 24-hour food recall (24HFR) and the food frequency questionnaire (FFQ) methods in socially vulnerable women in Brazil and compare these methods against doubly labeled water (DLW).

DESIGN

Cross-sectional study. Energy intake (EI) was measured using 3 24HFRs and 1 FFQ. Total energy expenditure (TEE) was measured using DLW. Cutoff points were calculated to assess underreporting and overreporting using both the difference and the ratio between the EI and TEE.

PARTICIPANTS/SETTING

Sixty-seven socially vulnerable, nondieting adult women with stable body weight and mothers of malnourished children.

MAIN OUTCOME MEASURES

EI, in kilocalories, derived from 24HFR and FFQ.

STATISTICAL ANALYSES

Repeated measures analysis of variance was used to compare EI and TEE and Bland-Altman graphs were plotted to assess the agreement between these variables. Spearman correlation coefficient between the ratio of EI to TEE and socioeconomic or anthropometric variables was calculated.

RESULTS

Mean TEE was 2,186 kcal (95% CI 2,063 to 2,309 kcal). EI obtained through 24HFR (mean=1,848.6 kcal [95% CI 1,737.5 to 1,959.7 kcal]) was significantly lower than TEE (P=0.01), and significantly lower than the EI obtained through FFQ (mean=2,084.5 [95% CI 1,929.0 to 2,240.0 kcal]; P<0.01). There were no statistically significant differences between the EI values of FFQ and TEE (P=0.89). The distribution of underreporters, nonunderreporters, and overreporters were more homogenous in the FFQ method. There was a positive correlation between body fat percentage and underreporting in the FFQ method (r=0.245; P=0.046).

CONCLUSIONS

The methods of assessing dietary intake in our study showed poor agreement with TEE obtained by DLW. These may, therefore, not be the most suitable methods for assessing EI in this population.

Association between Adult Stature and Energy Expenditure in Low-Income Women from Northeastern Brazil

Background

Perinatal undernutrition may lead to important metabolic adaptations in adult life, short stature being the most visible. The present study aimed to evaluate the association between stature and total energy expenditure of low-income women.

Method

Women aged 19–45 years from low-income communities in Maceió-AL were recruited. A sample of 67 volunteers was selected and divided into either short stature (≤152.4 cm; n = 34) or non-short stature (≥158.7 cm; n = 33) group. Data on socioeconomic status, anthropometric variables, and hormonal profiles was collected. Total energy expenditure and body composition were assessed by the doubly labeled water technique with multiple points over 14 days. In addition, physical activity levels were measured with triaxial accelerometers and dietary intake data were collected using three 24-hour food records.

Results

The mean subject age was 30.94 years. Women of short stature had lower body weight and lean body mass compared to non-short women, but there were no differences in thyroid hormone concentrations or daily energy intake between the two groups. Short-stature women showed lower total energy expenditure (P = 0.01) and a significantly higher physical activity level (P = 0.01) compared to non-short women. However, the difference in total energy expenditure was no longer significant after statistical adjustment for age, lean body mass, and triiodothyronine concentrations.

Conclusion

Women with short stature present the same energy intake, but lower total energy expenditure than non-short women, even with a higher physical activity level, which suggests that they are more prone to weight gain.

HEPATIC FATTY ACID PROFILE OF RATS FED A TRIHEPTANOIN-BASED KETOGENIC DIET

OBJECTIVE

the aim of this study was to evaluate the influence of consumption of a ketogenic diet supplemented with triheptanoin, a medium-chain anaplerotic triacylglycerol, on the liver fatty acid profile of Wistar rats.

METHODS

three groups of male Wistar rats (n = 10) were submitted to an AIN-93 control diet, a triheptanoin- based ketogenic diet, or a soybean oil-based ketogenic diet for 60 days. Excised livers were subjected to lipid extraction and methylation to obtain fatty acids methyl esters, which were subjected to gas chromatography- mass spectrometry.

RESULTS AND DISCUSSION

compared to the rats fed the control diet, those fed ketogenic diets showed a significant reduction in the concentrations of 9-hexadecenoic and 9-octadecenoic acids, whereas those fed triheptanoin showed increased levels of octadecanoic acid.

CONCLUSION

changes in the liver fatty acid profiles of the rats fed a triheptanoin-based or a soybean oil-based ketogenic diet did not seem to be related to the dietary fat source, but rather to the characteristics of the ketogenic diets themselves.

Dietary intake of ain-93 standard diet induces Fatty liver with altered hepatic fatty acid profile in Wistar rats

BACKGROUND

There are several standard diets for animals used in scientific research, usually conceived by scientific institutions. The AIN-93 diet is widely used, but there are some reports of fatty liver in Wistar rats fed this diet.

OBJECTIVE

We aimed to evaluate the hepatic repercussions of the AIN-93 diet intake in Wistar rats.

METHODS

Forty newly-weaned 21-day-old male Wistar rats were fed either the AIN-93 diet or a commercial diet for either 1 month or 4 months. Weight gain, serum biochemistry, hepatic histology, and hepatic fatty acid profile were analyzed.

RESULTS

Hepatic steatosis was observed, especially in the group fed the AIN-93 diet. Serum blood glucose, absolute and relative liver weight and hepatic levels of oleic, palmitoleic, stearic, and palmitic fatty acids were related to the observed steatosis, while lipidogram and serum markers of liver function and injury were not.

CONCLUSION

AIN-93 diet induced acute hepatic steatosis in Wistar rats, which may compromise its use as a standard diet for experimental studies with rodents. The hepatic fatty acid profile was associated with steatosis, with possible implications for disease prognosis.

Effects of ketogenic diets on the occurrence of pilocarpine-induced status epilepticus of rats

Two sources of medium-chain triglycerides--triheptanoin with anaplerotic properties and coconut oil with antioxidant features--have emerged as promising therapeutic options for the management of pharmacoresistant epilepsy. We investigated the effects of ketogenic diets (KDs) containing coconut oil, triheptanoin, or soybean oil on pilocarpine-induced status epilepticus (SE) in rats. Twenty-four adult male Wistar rats were divided into 4 groups and fed a control diet (7% lipids) or a KD containing soybean oil, coconut oil, or triheptanoin (69.8% lipids). The ketogenic and control diets had a lipid:carbohydrate + protein ratio of 1:11.8 and 3.5:1, respectively. SE was induced in all rats 20 days after initiation of the dietary treatment, through the administration of pilocarpine (340 mg/kg; i.p.). The latency, frequency, duration, and severity of seizures before and during SE were observed with a camcorder. SE was aborted after 3 h with the application of diazepam (5 mg/kg; i.p.). The rats in the triheptanoin-based KD group needed to undergo a higher number of seizures to develop SE, as compared to the control group (P < 0.05). Total weight gain, intake, energy intake, and feed efficiency coefficient, prior to induction of SE, differed between groups (P < 0.05), where the triheptanoin-based KD group showed less weight gain than all other groups, less energy intake than the Control group and intermediate values of feed efficiency coefficient between Control and other KDs groups. Triheptanoin-based KD may have a neuroprotective effect on the establishment of SE in Wistar rats.