Gaps in hypertension care and control: a population-based study in low-income urban Medellin, Colombia.

OBJECTIVES: To assess hypertension prevalence and the extent and associated factors of hypertension diagnosis, follow-up, treatment and control gaps in low-income urban Medellin, Colombia. METHODS: We randomly sampled 1873 adults aged 35 or older. Unaware hypertensive individuals were defined as those without previous diagnosis whose average blood pressure was equal to or above 140/90 mmHg. For aware hypertensive patients, control was delimited as average blood pressure below 140/90 if under 59 years old or diabetic, and as less than 150/90 otherwise. We used logistic regression to identify care gap-associated factors. RESULTS: Hypertension prevalence was 43.5% (95% CI 41.2-45.7). We found 28.2% aware and 15.3% unaware hypertensive individuals, which corresponds to a 35.1% (95% CI 31.9-38.5) underdiagnosis. This gap was determined by age, sex, education and lifestyle factors. 14.4% (95% CI 11.6-17.6) of aware hypertensive patients presented a follow-up gap, 93.4% (95% CI 90.9-95.2) were prescribed antihypertensive drugs, but 38.9% (95% CI 34.7-43.3) were not compliant. The latter was strongly associated with follow-up. The hypertension control gap in aware hypertensive patients, 39.0% (95% CI: 34.9-43.2), was associated with being older, having diabetes, weakly adhering to pharmacological treatment and receiving poor non-pharmacological advice. Overall, 60.4% (95% CI 57.0-63.8) of aware and unaware hypertensive participants had either diagnosed but uncontrolled or undiagnosed hypertension. CONCLUSIONS: We found high hypertension prevalence coupled with, from an international perspective, encouraging awareness and control figures. Still, there remains ample room for improvement. Our findings can assist in designing integrated primary healthcare measures that further strengthen equitable and effective access to hypertension care and control.

Quantification of molecular weight discrimination in grafting to reactions from ultrathin polymer films by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

In the present study, a reliable and robust method was developed to quantify the molecular weight discrimination that can occur in grafting to reactions via indirect MALDI-TOF quantification of the molecular weights of grafted chains by comparing the characteristics of the polymeric material before the grafting reaction with those of the unreacted material recovered after grafting. Two polystyrene samples with different molecular weights and narrow molecular weight distributions were employed to prepare model blends that were grafted to silicon wafers and an analytical method was developed and validated to assess and quantify the modification of the molecular weight distribution that takes place during the grafting to process. Particular attention was paid to the standardization of the sample treatment and to find the best data collection and calibration methodologies in order to have statistically significant data even in the presence of a very scarce amount of the sample. Furthermore, to evaluate the accuracy of the analytical procedure, the lack of suitable standard and certified materials required a further experiment to be carried out by comparing the new optimized MALDI-TOF method and direct measurements using TGA-GC-MS on a model blend containing deuterated and hydrogenated polystyrene samples with appropriate molecular weights and distributions. The optimized method was applied on samples obtained by a thermally induced grafting to reaction from ultrathin polymer films and, for the first time, to our knowledge, an enrichment effect occurring in the ultrathin grafted layer obtained from a melt was evidenced.

Protocol for a controlled before-after quasi-experimental study to evaluate the effectiveness of a multi-component intervention to reduce gaps in hypertension care and control in low-income communes of Medellin, Colombia.

INTRODUCTION: Research on public health interventions to improve hypertension care and control in low-income and middle-income countries remains scarce. This study aims to evaluate the effectiveness and assess the process and fidelity of implementation of a multi-component intervention to reduce the gaps in hypertension care and control at a population level in low-income communes of Medellin, Colombia. METHODS AND ANALYSIS: A multi-component intervention was designed based on international guidelines, cross-sectional population survey results and consultation with the community and institutional stakeholders. Three main intervention components integrate activities related to (1) health services redesign, (2) clinical staff training and (3) patient and community engagement. The effectiveness of the intervention will be evaluated in a controlled before-after quasi-experimental study, with two deprived communes of the city selected as intervention and control arms. We will conduct a baseline and an endline survey 2 years after the start of the intervention. The primary outcomes will be the gaps in hypertension diagnosis, treatment, follow-up and control. Effectiveness will be evaluated with the difference-in-difference measures. Generalised estimation equation models will be fitted considering the clustered nature of data and adjusting for potential confounding variables. The implementation process will be studied with mixed methods. Implementation fidelity will be documented to assess to which degree the intervention components were implemented as intended. ETHICS AND DISSEMINATION: The study protocol has been approved by the Ethics Research Committee of Metrosalud in Colombia (reference 1400/5.2), the Medical Ethics Committee of the Antwerp University Hospital (reference 18/40/424) and the Institutional Review Board of the Antwerp Institute of Tropical Medicine (reference 1294/19). We will share and discuss the study results with the community, institutional stakeholders and national health policymakers. We will publish them in national and international peer-reviewed scientific journals. TRIAL REGISTRATION NUMBER: NCT05011838.

Out-of-pocket expenditure for hypertension care: a population-based study in low-income urban Medellin, Colombia.

Background Hypertension requires life-long medical care, which may cause economic burden and even lead to catastrophic health expenditure. Objective To estimate the extent of out-of-pocket expenditure for hypertension care at a population level and its impact on households' budgets in a low-income urban setting in Colombia. Methods We conducted a cross-sectional survey in Santa Cruz, a commune in the city of Medellin. In 410 randomly selected households with a hypertensive adult, we estimated annual basic household expenditure and hypertension-attributable out-of-pocket expenditure. For socioeconomic stratification, we categorised households according to basic expenditure quintiles. Catastrophic hypertension-attributable expenditure was defined as out-of-pocket expenditure above 10% of total household expenditure. Results The average annual basic household expenditure was US dollars at purchasing power parity (USD-PPP) $12,255.59. The average annual hypertension-attributable out-of-pocket expenditure was USD-PPP $147.75 (95% CI 120.93-174.52). It was incurred by 73.9% (95% CI 69.4%-78.1%) of patients, and consisted mainly of direct non-medical expenses (76.7%), predominantly for dietary requirements prescribed as non-pharmacological treatment and for transport to attend health care consultations. Medical out-of-pocket expenditure (23.3%) was for the most part incurred for pharmacological treatment. Hypertension-attributable out-of-pocket expenditure represented on average 1.6% (95% CI 1.3%-1.9%) of the total annual basic household expenditure. Eight households (2.0%; 95% CI 1.0%-3.8%) had catastrophic health expenditure; six of them belonged to the two lowest expenditure quintiles. Payments related to dietary requirements and transport to consultations were critical determinants of their catastrophic expenditure. Conclusions Out-of-pocket expenditure for hypertension care is moderate on average, but frequent, and mainly made up of direct non-medical expenses. Catastrophic health expenditure is uncommon and affects primarily households in the bottom socioeconomic quintiles. Financial protection should be strengthened by covering the costs of chronic diseases-related dietary requirements and transport to health services in the most deprived households. Abbreviations NCDs: Non-communicable diseases; LMICs: Low and middle-income countries; WHO: World Health Organization; HTN: hypertension; CVDs: Cardiovascular diseases; OOPE: out-of-pocket expenditure; USD-PPP: US dollars at purchasing power parity; CI: Confidence interval.

Thermal Hyperactivation and Stabilization of ß-Galactosidase from Bacillus circulans through a Silica Sol-Gel Process Mediated by Chitosan-Metal Chelates.

The research of simple and fast enzyme immobilization methods, preserving the enzyme activity and improving the thermal stability, is in the spotlight. The objective of this work is to develop a ß-galactosidase immobilization one-pot route, combining the silica sol-gel encapsulation (SSGE) process with a metal chelation strategy by using chitosan and Ca2+, Zn2+, or Cu2+ cations. The results show that the presence of cations does not affect the encapsulation efficiency (81%) and has positive effects on the maximum catalytic potential, especially at 60 °C and in the presence of Ca2+ ions (MPC = 2203). They enhance the biocatalyst thermal stability and promote hyperactivation with respect to the soluble enzyme at 60 °C (1.6 times higher MPC). The biocatalyst prepared with Zn2+ ions exhibits also thermal hyperactivation in the first 30 min of heating (1.3 times more residual activity), but the enzyme is not stabilized (0.9 times lower MPC); also, the presence of Cu2+ ions does not promote hyperactivation or stabilization of the enzyme (0.3 times lower MPC) at this high temperature. These facts are reflected in the hydrolytic and transgalactosylation activities of the enzyme (33.6-57.4% total lactose conversion), higher than that reported with analogue biocatalysts. The physicochemical characterization of the obtained solid biocatalysts by SEM, TEM, XRF, and XPS indicates that chitosan-metal chelation has an important role in the encapsulation process and that a low metal degree incorporation (8.85 ppm of Ca2+) on the solid biocatalyst favors the thermal hyperactivation and stabilization of the evaluated ß-galactosidase. This work contributes to the understanding of the SSGE process mediated by chitosan-metal chelates, which is a simple and fast one-pot immobilization strategy.