Relationship between urinary sodium with blood pressure and hypertension among a Kazakh community population in Xinjiang, China

The association between dietary sodium intake and obesity in adults by sodium intake assessment methods: a review of systematic reviews and re-meta-analysis

BACKGROUND/OBJECTIVES

The scientific evidence of a sodium-obesity association is limited by sodium intake assessments. Our specific aim is to synthesize the association between dietary sodium intake and obesity across the sodium intake assessments as evidenced by systematic reviews in adults.

SUBJECTS/METHODS

A systematic search identified systematic reviews comparing the association of dietary sodium intakes with obesity-related outcomes such as body mass index (BMI), body weight, waist circumference, and risk of (abdominal) obesity. We searched PubMed on October 24, 2022. To assess the Risk of Bias in Systematic Reviews (ROBIS), we employed the ROBIS tool.

RESULTS

This review included 3 systematic reviews, consisting of 39 unique observational studies (35 cross-sectional studies and 4 longitudinal studies) and 15 randomized controlled trials (RCTs). We found consistently positive associations between dietary sodium intake and obesity-related outcomes in cross-sectional studies. Studies that used 24-h urine collection indicated a greater BMI for those with higher sodium intake (mean difference = 2.27 kg/m2; 95% confidence interval [CI], 1.59-2.51; P < 0.001; I2 = 77%) compared to studies that used spot urine (mean difference = 1.34 kg/m2; 95% CI, 1.13-1.55; P < 0.001; I2 = 95%) and dietary methods (mean difference = 0.85 kg/m2; 95% CI, 0.1-1.51; P < 0.05; I2 = 95%).

CONCLUSIONS

Quantitative synthesis of the systematic reviews has shown that cross-sectional associations between dietary sodium intake and obesity outcomes were substantially different across the sodium intake assessments. We need more high-quality prospective cohort studies and RCTs using 24-h urine collection to examine the causal effects of sodium intake on obesity.

Effects of Simplified Antihypertensive Treatment Algorithm on Hypertension Management and Hypertension-Related Death in Resource-Constricted Primary Care Setting between 1997 and 2017

Hypertension management is poor in primary care settings of developing countries, where 75% of hypertensives are living. Exploring better ways to improve hypertension management and to decrease stroke and CVD death is needed such as introducing treatment algorithm. Therefore, we selected intervention counties from Xinjiang, an underdeveloped region in China, and introduced antihypertensive treatment algorithm, comprising locally available and affordable agents, to primary health providers since 1998. Program effects were evaluated using the data collected in various ways including cross-sectional screenings to population ≥30 years between 1998 and 2015 by comparing treatment and control rates of hypertension, changes in blood pressure (BP) levels and distribution, and proportion of case/total and NCD death for CVD and stroke. Compared to 1998–2000, treatment rate was improved by 2.78 fold (11.2% vs. 32.1%, P < 0.001), and the overall and treated control rate were improved by 53.5 fold (0.2% vs. 10.7%, P < 0.001) and by 16.8 fold (2.0% vs. 33.5%, P < 0.001), respectively, in 2015. Mean SBP and DBP showed a net reduction by 33.7 mmHg (181.3 vs. 147.6 mmHg) and 21.3 mmHg (106.3 vs. 85.0 mmHg), respectively, in 2015, compared to 1998–2000 (P < 0.001), and stage III hypertension was reduced by 75.2% (33.5 vs. 8.3%, P < 0.001). Compared to 1997–1999, stroke/NCD death was reduced by 34.1% in 2015–2017 (31.7 vs. 20.9%, P = 0.006) in the intervention counties whereas by 7.5% in control county. Introduction of treatment algorithm helps improve hypertension management and reduce stroke death in resource-constricted primary settings.

Association between 24-h urinary sodium to potassium ratio and mild cognitive impairment in community-based general population

OBJECTIVE

To explore the relationship between parameters of Na and K excretion using 24-h urine sample and mild cognitive impairment (MCI) in general population.

DESIGN

This is a cross-sectional study.

SETTING

Community-based general population in Emin China.

PARTICIPANTS

Totally, 1147 subjects aged ≥18 years were selected to complete the study, with a multistage proportional random sampling method. Cognitive status was assessed with Mini Mental State Examination (MMSE) questionnaire and timed 24-h urine specimens were collected. Finally, 561 participants aged ≥35 years with complete urine sample and MMSE data were included for the current analysis and divided into groups by tertiles of 24-h urinary sodium to potassium ratio (24-h UNa/K) as lowest (T1), middle (T2) and highest (T3) groups.

RESULTS

The MMSE score was significantly lower in T3, compared with the T1 group (26·0 v. 25·0, P = 0·002), and the prevalent MCI was significantly higher in T3 than in T1 group (11·7 % v. 25·8 %, P < 0·001). In multiple linear regression, 24-UNa/K (β: -0·184, 95 % CI -0·319, -0·050, P = 0·007) was negatively associated with MMSE score. In multivariable logistic regression, compared with T1 group, 24-h UNa/K in the T2 and T3 groups showed 2·01 (95 % CI 1·03, 3·93, P = 0·041) and 3·38 (95 % CI 1·77, 6·44, P < 0·001) fold odds for presence of MCI, even after adjustment for confounders. More augmented results were demonstrated in sensitivity analysis by excluding individuals taking anti-hypertensive agents.

CONCLUSIONS

Higher 24-h UNa/K is in an independent association with prevalent MCI.

The association between dietary sodium intake, adiposity and sugar-sweetened beverages in children and adults: a systematic review and meta-analysis

Higher intakes of Na may contribute to weight gain. The primary aim of this systematic review and meta-analysis was to examine the relationship between dietary Na intake and measures of adiposity in children and adults. Given the previous link between Na intake and the consumption of sugar-sweetened beverages (SSB), which are a known risk factor for obesity, a secondary aim examining the relationship between Na intake and SSB consumption was assessed. A systematic literature search identified cross-sectional and longitudinal studies and randomised controlled trials (RCT) which reduced dietary Na (≥3 months). Meta-analysis was performed for outcomes with ≥3 studies. Cross-sectionally higher Na intakes were associated with overweight/obesity in adults (five studies; n 11 067; OR 1·74; 95 % CI 1·43, 2·13) and in children (three studies; n 3625, OR 3·29; 95 % CI 2·25, 4·80), and abdominal obesity (five studies; n 19 744; OR 2·04; 95 % CI 1·72, 2·42) in adults. Overall, associations remained in sensitivity analyses which adjusted for energy. Findings from longitudinal studies were inconsistent. RCT in adults indicated a trend for lower body weight on reduced-Na compared with control diets (fifteen studies; n 5274; -0·29 kg; 95 % CI -0·59, 0·01; P = 0·06); however, it is unclear if energy intakes were also altered on reduced-Na diets. Among children higher Na intakes were associated with higher intake of SSB (four studies, n 10 329, b = 22, 16 and 26 g/d); no studies were retrieved for adults. Overall, there was a lack of high-quality studies retrieved. While cross-sectional evidence indicates Na intake was positively associated with adiposity, these findings have not been clearly confirmed by longitudinal studies or RCT.

Dietary Sodium Intake and Health Indicators: A Systematic Review of Published Literature between January 2015 and December 2019

As the science surrounding population sodium reduction evolves, monitoring and evaluating new studies on intake and health can help increase our understanding of the associated benefits and risks. Here we describe a systematic review of recent studies on sodium intake and health, examine the risk of bias (ROB) of selected studies, and provide direction for future research. Seven online databases were searched monthly from January 2015 to December 2019. We selected human studies that met specified population, intervention, comparison, outcome, time, setting/study design (PICOTS) criteria and abstracted attributes related to the study population, design, intervention, exposure, and outcomes, and evaluated ROB for the subset of studies on sodium intake and cardiovascular disease risks or indicators. Of 41,601 abstracts reviewed, 231 studies were identified that met the PICOTS criteria and ROB was assessed for 54 studies. One hundred and fifty-seven (68%) studies were observational and 161 (70%) focused on the general population. Five types of sodium interventions and a variety of urinary and dietary measurement methods were used to establish and quantify sodium intake. Five observational studies used multiple 24-h urine collections to assess sodium intake. Evidence mainly focused on cardiovascular-related indicators (48%) but encompassed an assortment of outcomes. Studies varied in ROB domains and 87% of studies evaluated were missing information on ≥1 domains. Two or more studies on each of 12 outcomes (e.g., cognition) not previously included in systematic reviews and 9 new studies at low ROB suggest the need for ongoing or updated systematic reviews of evidence on sodium intake and health. Summarizing evidence from assessments on sodium and health outcomes was limited by the various methods used to measure sodium intake and outcomes, as well as lack of details related to study design and conduct. In line with research recommendations identified by the National Academies of Science, future research is needed to identify and standardize methods for measuring sodium intake.

Sodium and potassium intakes in the Kazakhstan population estimated using 24-h urinary excretion: evidence for national action

PURPOSE

There is strong scientific evidence for reducing sodium and increasing potassium intake to the recommended levels to lower blood pressure and cardiovascular risk, but consumption levels in Kazakhstan are unknown. This study sought to estimate mean sodium and potassium intake using 24-h urine samples and describe dietary knowledge and behavior among adults in Kazakhstan.

METHODS

In two cross-sectional surveys, the same multi-stage cluster sampling method was used to randomly select participants aged 25-64 years from Almaty City in 2015 and Kyzylorda in 2016. Complete 24-h urine samples were available for 478 participants; 294 in Almaty City and 184 in Kyzylorda (response rates 86% and 54%, respectively) and were weighted for the age and sex distribution of the two regions.

RESULTS

Weighted mean 24-h urinary sodium excretion was 6782 mg/day (17.2 g salt) (95% CI 6507-7058) in both regions combined, and not significantly different between the regions (P = 0.660). 99% of adults in the two regions combined consumed above the World Health Organization's (WHO) recommended sodium maximum of 2000 mg/day; however, only 15% of adults perceived that they consumed excess sodium. Weighted mean 24-h urinary potassium excretion was 2271 mg/day (95% CI 2151-2391) for the regions combined.

CONCLUSION

Mean sodium consumption in Kazakhstan was more than triple the WHO's recommended maximum, and mean potassium consumption was below the recommended minimum. National efforts to lower sodium intake and increase potassium intake are needed and would likely prevent ample premature deaths and disease burden.

Distribution characteristics of circulating homocysteine and folate and related factors in agriculture, stock-raising and urban populations: a cross-sectional survey

OBJECTIVE

To investigate homocysteine (Hcy) and folate levels, prevalence of hyperhomocysteinaemia (HHcy) and folate deficiency, which are affected by lifestyles in urban, agricultural and stock-raising populations.

DESIGN

This is a cross-sectional study.

SETTING

Urban, agricultural and stock-raising regions in Emin, China.

PARTICIPANTS

Totally 1926 subjects - 885 (45·9 %) from urban, 861 (44·7 %) from agricultural and 180 (9·4 %) from stock-raising regions - were obtained using multistage stratified random sampling. Inclusion criteria encompassed inhabitants aged ≥15 years who resided at the current address for ≥6 months and agreed to participate in the study. Surveys on health behaviour questionnaires and physical examinations were conducted and blood samples collected.

RESULTS

The folate level of subjects from the stock-raising region was the lowest, followed by those from the agricultural region, and the highest in those from the urban region (3·48 v. 6·50 v. 7·12 ng/ml, P < 0·001), whereas mean Hcy showed no significant difference across regions. The OR for HHcy in stock-raising regions was 1·90 (95 % CI 1·11, 3·27) compared with the urban region after adjusting for all possible covariates. The OR for folate deficiency in stock-raising and agriculture regions was 11·51 (95 % CI 7·09, 18·67) and 1·91 (95 % CI 1·30, 2·82), respectively, compared with the urban region after adjusting for all possible covariates.

CONCLUSIONS

HHcy and folate deficiency are highly prevalent in stock-raisers, which is of important reference for HHcy control in Xinjiang, with a possibility of extension to others with approximate lifestyles.

Prevalence, Awareness, Treatment, and Control and Related Factors of Hypertension in Multiethnic Agriculture, Stock-Raising, and Urban Xinjiang, Northwest China: A Cross-Sectional Screening for 47000 Adults

Background

Hypertension is the leading cause of cardiovascular disease. Distribution of hypertension and related factors among multiethnic population in Northwest China remains scarce. The aim was to determine prevalence, awareness, treatment, control, and risk factors associated with hypertension among multiethnic population in Northwest China.

Methods

We conducted a blood pressure (BP) screening project covering a third of adults in Emin Xinjiang, Northwest China, during 2014–2016. Hypertension was defined as systolic BP ≥ 140 mmHg, diastolic BP ≥ 90 mmHg, and/or taking antihypertension drugs. We compared prevalence, awareness, treatment, and control of hypertension and related factors by different regions (agriculture, stock-raising, or urban) and by ethnic groups.

Results

Totally 47,040 adults were screened with 48.5% women. Overall prevalence, awareness, treatment, and control of hypertension were 26.5%, 64.6%, 44.5%, and 15.3%, respectively. Age-gender-adjusted hypertension prevalence was higher in urban (28.2%) than in other regions and in Kazakh (30.3%) than in others. The lowest awareness and treatment rates were observed in the agricultural region and in Kazakh subjects, while the lowest control was in the stock-raising region (13.8%) and in Kazakh subjects (12.6%). After adjusting for age, gender, ethnicity, and regions, compared to normal weight, nonsmokers, and nondrinkers, obesity, smoking, and alcohol intake were significantly related to increased prevalence of hypertension by 94%, 1.5, and 3.9 folds, respectively.

Conclusions

Disparities in hypertension control among regions and ethnic groups suggested inadequate screening and treatment, especially in stock-raising regions and Kazakh populations. Control of alcohol intake, smoking, and obesity should be at high priority of health promotion.

Paucity of high-quality studies reporting on salt and health outcomes from the science of salt: A regularly updated systematic review of salt and health outcomes (April 2017 to March 2018)

The purpose of this review is to identify, summarize, and critically appraise studies on dietary salt and health outcomes that were published from April 2017 to March 2018. The search strategy was adapted from a previous systematic review on dietary salt and health. Identified studies were screened based on a priori defined criteria to identify publications eligible for detailed critical appraisals. Overall, 6747 citations were identified by the search strategy, and 42 health outcome studies were identified. Three of the 42 studies met the criteria for methodological quality and health outcomes and underwent detailed critical appraisals and commentary. In addition, a systematic review and meta-analysis was critically appraised, although it did not strictly meet our methodological criteria. All four of the studies critically appraised found that sodium reduction improved blood pressure, especially in individuals with hypertension. In addition, sodium reduction reduced albuminuria in patients with stage 1-3 chronic kidney disease. Examination of the time course of blood pressure responses to sodium reduction revealed lowering sodium in the context of an average American diet may not produce maximal blood pressure reductions within a 4-week intervention period. This review provides further evidence of the benefit of sodium reduction for blood pressure lowering and gives insights into the subgroups of the population that may derive the greatest benefit from sodium reduction and the time course required to see benefit. Only three high-quality studies were identified during this 12-month review period, highlighting the critical need for more well-conducted rigorous studies in this area.