Erythrocyte glycocalyx sensitivity to sodium is associated with salt sensitivity of blood pressure in women but not men

BackgroundWhile salt sensitivity of blood pressure (SSBP) is a risk factor for hypertension, end-organ damage and death, most studies are conducted in western countries and in White people. We previously found that the prevalence of SSBP in Blacks living in Sub-Saharan Africa is as high as 75–80% like what has been reported in the west. Erythrocyte glycocalyx sensitivity to sodium (eGCSS), a marker of sodium-induced damage to the erythrocyte and vascular endothelial glycocalyx is thought to be related to blood pressure perturbations associated with salt intake. We hypothesized that SSBP correlates with eGCSS differently in men and women in Black people.MethodsWe conducted a cross sectional study using data from our recent clinical trial from Livingstone University Teaching Hospital among 117 normotensive young adults. We used a “salt blood test” to determine eGCSS and an immediate pressor response to oral salt (IPROS) for the diagnosis of SSBP.ResultsThe proportion of males were equal to females and the median age (interquartile range) of the participants was 29 (22–45) years. The eGCSS scores were higher in salt-resistant females compared to salt-sensitive females and males. eGCSS correlated negatively with SSBP (AOR 0.98, 95% CI 0.97–0.99, p = 0.008), however, this relationship was driven by female sex and abrogated by male sex. Although blood pressure elevations exhibited a sustained bimodal pattern in both sexes, in males, systolic and diastolic blood pressure never returned to baseline during the time course as it did in females.ConclusionIn this study, eGCSS correlated negatively with SSBP in black women but not in black men and the pressor response to dietary salt was significantly higher in men compared to women. These results suggest that women tend to have a higher disruption of the vascular endothelial glycocalyx by an acute salt load, implying that acute changes in blood pressure may not be driven directly by the endothelial glycocalyx. Our findings suggest a novel mechanism linking eGCSS and SSBP with potential implications for sex differences in salt-induced cardiovascular disease.Clinical trial registration: https://clinicaltrials.gov/, identifier [NCT04844255]

Immediate pressor response to oral salt and its assessment in the clinic: a time series clinical trial

Background: High blood pressure (BP) is associated with high-salt consumption especially in sub-Saharan Africa. Although the pressor efect of salt is viewed as a chronic efect, some studies suggest that a salty meal may increase BP immediately in some individuals, and that this efect may cause endothelial dysfunction. Therefore, the aim of our research was to study the immediate pressor response to oral salt (IPROS) and its determinants, with the expectation that a simple methodology may be devised to diagnose it in the clinic or in low-resource environments. Methods: We conducted a time series trial at Livingstone Central Hospital. We present data in 127 normotensive participants who ingested 2g of sodium chloride; their BP was monitored for 120minutes in intervals of 10minutes. Sociodemographic and clinical data were collected. Descriptive and inferential statistics were used for analyses of data. Results: Median age was 30 years (interquartile range, 22–46 years) and 52% were female patients. An increase of ≥10mmHg in mean arterial pressure (MAP), considered a clinically signifcant IPROS, was present in 62% of participants. Systolic BP 30minutes after the salt load was a signifcant predictor of IPROS, avoiding the need to calculate MAP in the clinic setting. Conclusions: We confrm the presence of an IPROS in a high proportion (62%) of otherwise normotensive participants. The average time course for this response was 30minutes and its duration was sustained for the 120-minutes period of study in most of the participants. Prediction of IPROS by ∆SBP (change in systolic blood pressure) at 30minutes allows for easy assessment of possible responder status in the clinic. Our data indicate that the IPROS to oral saltloads in the range currently consumed by the Western world and African populations in single meals may increase the 24-hour BP load, which is a risk factor for hypertension and target organ damage. The relevance of our fndings indicates the need to include dietary sodium assessment in the diagnosis, prevention, and management of high BP

HIV test-and-treat policy improves clinical outcomes in Zambian adults from Southern Province: a multicenter retrospective cohort study

BackgroundGlobally, most countries have implemented a test-and-treat policy to reduce morbidity and mortality associated with HIV infection. However, the impact of this strategy has not been critically appraised in many settings, including Zambia. We evaluated the retention and clinical outcomes of adults enrolled in antiretroviral therapy (ART) and assessed the impact of the test-and-treat policy.MethodsWe conducted a retrospective cohort study among 6,640 individuals who initiated ART between January 1, 2014 and July 31, 2016 [before test-and-treat cohort (BTT), n = 2,991] and between August 1, 2016 and October 1, 2020 [after test-and-treat cohort (ATT), n = 3,649] in 12 districts of the Southern province. To assess factors associated with retention, we used logistic regression (xtlogit model).ResultsThe median age [interquartile range (IQR)] was 34.8 years (28.0, 42.1), and 60.2% (n = 3,995) were women. The overall retention was 83.4% [95% confidence interval (CI) 82.6, 84.4], and it was significantly higher among the ATT cohort, 90.6 vs. 74.8%, p < 0.001. The reasons for attrition were higher in the BTT compared to the ATT cohorts: stopped treatment (0.3 vs. 0.1%), transferred out (9.3 vs. 3.2%), lost to follow-up (13.5 vs. 5.9%), and death (1.4 vs. 0.2%). Retention in care was significantly associated with the ATT cohort, increasing age and baseline body mass index (BMI), rural residence, and WHO stage 2, while non-retention was associated with never being married, divorced, and being in WHO stage 3.ConclusionThe retention rate and attrition factors improved in the ATT compared to the BTT cohorts. Drivers of retention were test-and-treat policy, older age, high BMI, rural residence, marital status, and WHO stage 1. Therefore, there is need for interventions targeting young people, urban residents, non-married people, and those in the symptomatic WHO stages and with low BMI. Our findings highlight improved ART retention after the implementation of the test-and-treat policy

Treatment-seeking behaviour for childhood fever among caretakers of Chivuna and Magoye rural communities of Mazabuka District, Zambia: a longitudinal study

Abstract Background Treatment-seeking for childhood fever among caretakers in most rural parts of African region is still a major challenge. The aim of this study was to determine the treatment seeking behaviour for fever in under-5 children of Magoye and Chivuna rural areas of Mazabuka district in Zambia. Methods Treatment-seeking behaviour was explored longitudinally among caretakers of 362 children aged 12–59 months with fever. The data was collected from caretakers using a structured interviewer-administered questionnaire at their homes. Chi-square test, one-sample test of proportions and logistic regression were the statistical methods used for data analysis. Results Of the 362 children with fever, 77 % of them had their treatment sought externally. In which 64 % had their treatment at health facility (HF), 18 % from community health workers (CHW), and 18 % from other sources. Early treatment (≤ 24 h) was sought for 42 % of the fever episodes. In dry season, a child had 1.53 times more likely to have early treatment compared to rainy season [OR 1.53; 95 % CI 1.30, 1.80; p < 0.001]. A child in Chivuna was less likely to have early treatment compared to one in Magoye [OR 0.62; 95 % CI 0.50, 0.76; p < 0.001]. Caretakers had a reduced chance of 27 % [OR 0.73; 95 % CI 0.56, 0.95; p = 0.022] of seeking early treatment if they took a child to other sources compared to a HF. Conclusion This study has revealed that seeking early and appropriate treatment was suboptimal in the study areas. Source of treatment, season and location were predictors of early treatment of fever among caretakers. Policies aimed at combating poor care-seeking behaviour should not omit to address these factors

Rifampicin resistance in mycobacterium tuberculosis patients using GeneXpert at Livingstone Central Hospital for the year 2015: a cross sectional explorative study

Abstract Background Since the recent introduction of GeneXepert for the detection of Tuberculosis (TB) drug resistance mutations in both primary resistance and acquired resistance in Zambia, little has been documented in literature on the issue of rifampicin resistance especially in the face of a high National TB burden. The study aimed to determine the prevalence of rifampicin resistance in tuberculosis patients at Livingstone Central Hospital for the year 2015. Methods This was a cross sectional study conducted at Livingstone Central Hospital where we reviewed 152 records (from January 1, 2015 to 31st December, 2015) involving patients who presented with clinically suspected TB or documented TB, whose samples were sent to the laboratory for GeneXpert Mycobacterium tuberculosis/rifampicin testing. Statistical evaluations used a one-sample test of proportion and Fisher’s exact test. Results The age of participants ranged from 8 months to 73 years old (median = 34). Of the participants with complete data on gender, 99 (66%) and 52 (34%) were males and females respectively. The TB co-infection with HIV prevalence was 98.3% (p < 0.001). Prevalence of rifampicin resistance was 5.9% and there was no statistical significant difference between being male or female (p = 0.721). Conclusion We were able to show from our study, evidence of rifampicin resistance at Livingstone Central Hospital. Hence, there was need for further in-depth research and appropriate interventions (i.e close follow-up and patient care for drug resistance positive patients)

Productivity-adjusted life-years and correlates of uncontrolled hypertension at two health facilities in Zambia.

BackgroundHypertension has in the recent past surfaced as one of the conditions that has a significant impact on workforce productivity in emerging economies. Zambia is no different and has in the recent past recorded increasing cases. Despite the impact of hypertension being of great importance in regards to productivity, we have scarcity of data and studies on hypertension-related Productivity-Adjusted Life-Years (PALYs) in Zambia and Africa at large. This study assessed the impact of hypertension on PALYs lost and socioeconomic factors associated with nonadherence to antihypertensive medication (NATAM).MethodsThis was a cross-sectional study of 198 participants from Livingstone University Teaching Hospital and Maramba Clinic situated in Livingstone, Zambia. Structured questionnaires were used to collect data. Productivity index multiplied by years lived was used to calculate PALYs and descriptive statistics were used to summarize sociodemographic, clinical and economic variables. Multivariable logistic regression was used to determine factors associated with NATAM.ResultsThe participants had a median age (interquartile range (IQR)) of 49 years (41, 59) and 60.1% (n = 119) were females while 39.9% (n = 79) were male. Our estimated PALYs lost per person due to hypertension were 0.2 (IQR 0.0, 2.7). Cumulative PALYs value lost due to the burden of hypertension was estimated to be at $871,239.58 in gross domestic product (GDP). The prevalence of NATAM was 48% (n = 95). The factors that were significantly associated with NATAM were age (odds ratio (OR) 0.94; 95% confidence interval (CI) 0.90, 0.98), female sex (OR 2.52; 95%CI 1.18, 5.40), self-employment (OR 2.57; 95%CI 1.02, 6.45) and absenteeism from work (OR 3.60; 95%CI 1.16, 11.22).ConclusionsFindings in our study highlight a high economic loss of PALYs due to hypertension with a potential to impact GDP negatively. We also found that NATAM reduced productivity and income among individuals of working age further impacting PALYs lost due to hypertension. The factors associated with NATAM were age, sex, employment status and absenteeism from work. This study underscores the need for interventions targeting young people, females, self-employed individuals, and absentees at work to improve adherence to antihypertensive drugs in order to reduce PALYs lost due to hypertension

Lessons from a comparison of immuno-chromatographic and chemiluminescent micro-particle immunoassay in the diagnosis of syphilis

Abstract Objective To synthesize lessons from comparison of results obtained from the immuno-chromatographic SD Bioline testing method and the chemiluminescent micro-particle immunoassay Architect in the diagnosis of syphilis at Livingstone Central hospital laboratory. Results The specificity and sensitivity of SD Bioline syphilis 3.0 against the chemiluminescent immunoassay using the Architect syphilis Treponema pallidum (TP) was 85.3% and 91.3% respectively with substantial agreement between the two test methods (88%, ĸ  = 0.76; p < 0.0005). We recommend further comprehensive study with a larger sample size and clinical details to ascertain the validity of our findings. We also recommend using a non-treponemal test with the current treponemal tests being used to aid diagnosis

Table_1_Erythrocyte glycocalyx sensitivity to sodium is associated with salt sensitivity of blood pressure in women but not men.pdf

BackgroundWhile salt sensitivity of blood pressure (SSBP) is a risk factor for hypertension, end-organ damage and death, most studies are conducted in western countries and in White people. We previously found that the prevalence of SSBP in Blacks living in Sub-Saharan Africa is as high as 75–80% like what has been reported in the west. Erythrocyte glycocalyx sensitivity to sodium (eGCSS), a marker of sodium-induced damage to the erythrocyte and vascular endothelial glycocalyx is thought to be related to blood pressure perturbations associated with salt intake. We hypothesized that SSBP correlates with eGCSS differently in men and women in Black people.MethodsWe conducted a cross sectional study using data from our recent clinical trial from Livingstone University Teaching Hospital among 117 normotensive young adults. We used a “salt blood test” to determine eGCSS and an immediate pressor response to oral salt (IPROS) for the diagnosis of SSBP.ResultsThe proportion of males were equal to females and the median age (interquartile range) of the participants was 29 (22–45) years. The eGCSS scores were higher in salt-resistant females compared to salt-sensitive females and males. eGCSS correlated negatively with SSBP (AOR 0.98, 95% CI 0.97–0.99, p = 0.008), however, this relationship was driven by female sex and abrogated by male sex. Although blood pressure elevations exhibited a sustained bimodal pattern in both sexes, in males, systolic and diastolic blood pressure never returned to baseline during the time course as it did in females.ConclusionIn this study, eGCSS correlated negatively with SSBP in black women but not in black men and the pressor response to dietary salt was significantly higher in men compared to women. These results suggest that women tend to have a higher disruption of the vascular endothelial glycocalyx by an acute salt load, implying that acute changes in blood pressure may not be driven directly by the endothelial glycocalyx. Our findings suggest a novel mechanism linking eGCSS and SSBP with potential implications for sex differences in salt-induced cardiovascular disease.Clinical trial registration: https://clinicaltrials.gov/, identifier [NCT04844255].</p

The value of procalcitonin and C-reactive protein as early markers of bacteraemia among patients with haematological malignancies receiving chemotherapy: a cross-sectional study

Background: The immune system of patients with haematological malignancies is suppressed during chemotherapy. This renders them vulnerable to frequent infections especially of the bacterial type. Timely diagnosis of these infections is difficult, because a severe infection may be asymptomatic or manifest only in the form of fever or malaise. There is need for laboratory markers that can detect an infectious process at an early stage. This study was aimed at determining the value of using Procalcitonin (PCT) and C reactive protein (CRP), for early diagnosis of infection in patients with haematological malignancies receiving chemotherapy.Methods: This was a cross sectional study consisting of sixty eight (68) patients with haematological malignancies. Data from each participant including sex, age, clinical and laboratory data were collected after obtaining informed consent. Blood specimens were then collected for measurement of PCT, CRP and bacteriological analysis. Patients were divided into two groups; those with a culture positive and negative result. PCT and CRP concentrations were compared between groups using t-test and nonparametric statistical tests respectively. The area under ROC curve, sensitivity, specificity, likelihood ratio, and Spearman's correlation coefficient were also calculated.Results: Atotal of 14 (20.6%) microorganisms were isolated, of which 10 were gram-positive bacteria and 4 were gram-negative bacilli. The mean values of PCT which were 6.1ng/mL in the bacteraemia group and 5.1ng/mL in the non-bacteraemia group, p=0.023 and median CRP values were 24.2 (6.43- 48.15) in the bacteraemia and 23.5 (6.03-75.44) in the non-bacteraemia group, p=0.832. The area under curves was 0.52 (95% CI=0.57-0.84) for CRP and 0.70 (95% CI=0.35-0.69) for PCT. PCT value of greater than 4.7 ng/mL is diagnostic for infections (sensitivity 86%, specificity 54%) while that of CRP was 21mg/mL with the sensitivity and specificity of 64% and 44% respectively. Elevated levels of PCT as well as fever were significantly associated with bacteraemia.Conclusion: PCT was a more reliable and sensitive marker of bacteraemia among patients with  haematological malignancies receiving chemotherapy than CRP.Keywords: Procalcitonin (PCT), C reactive protein (CRP), Haematological Malignancies, Bacteraemia Marke