María Kathia Cárdenas

Rapid implementation of new TB diagnostic tests: is it too soon for a global roll-out of Xpert MTB/RIF?

In 2011 the World Health Organization approved Xpert MTB/RIF for tuberculosis diagnosis and recommended its rapid implementation. Xpert MTB/RIF is accurate: sensitivity is 72.5 -98.2% (smear-negative and -positive cases, respectively) and specificity 99.2%. Benefits include same-day diagnosis and simultaneous detection of rifampicin resistance. However, the test has some shortcomings and has not had time for thorough evaluation. Cost-effectiveness studies are difficult to perform and few have been completed. Existing data suggest cost-effectiveness in some, but not all, settings. The urgent need for better diagnostics is evident. Yet, serial implementation of new technologies causes ineffective spending and fragmentation of services. How new tests are incorporated into existing diagnostic algorithms affects both outcomes and costs. More detailed data on performance, effect on patient-important outcomes, and costs when used with adjunct tests are needed for each setting before implementation. While awaiting further clarification it seems prudent to slow its implementation among resource-constrained tuberculosis control programs.

Launching a salt substitute to reduce blood pressure at the population level: a cluster randomized stepped wedge trial in Peru

BackgroundControlling hypertension rates and maintaining normal blood pressure, particularly in resource-constrained settings, represent ongoing challenges of effective and affordable implementation in health care. One of the strategies being largely advocated to improve high blood pressure calls for salt reduction strategies. This study aims to estimate the impact of a population-level intervention based on sodium reduction and potassium increase – in practice, introducing a low-sodium, high-potassium salt substitute – on adult blood pressure levels.Methods/DesignThe proposed implementation research study includes two components: Phase 1, an exploratory component, and Phase 2, an intervention component. The exploratory component involves a triangle taste test and a formative research study designed to gain an understanding of the best implementation methods. Phase 2 involves a pragmatic stepped wedge trial design where the intervention will be progressively implemented in several clusters starting the intervention randomly at different times. In addition, we will evaluate the implementation strategy using a cost-effectiveness analysis.DiscussionThis is the first project in a Latin-American setting to implement a salt substitution intervention at the population level to tackle high blood pressure. Data generated and lessons learnt from this study will provide a strong platform to address potential interventions applicable to other similar low- and middle-income settings.Trial registrationThis study is registered in ClinicalTrials.gov NCT01960972.

Behaviour change strategies for reducing blood pressure-related disease burden: findings from a global implementation research programme

BackgroundThe Global Alliance for Chronic Diseases comprises the majority of the world’s public research funding agencies. It is focussed on implementation research to tackle the burden of chronic diseases in low- and middle-income countries and amongst vulnerable populations in high-income countries. In its inaugural research call, 15 projects were funded, focussing on lowering blood pressure-related disease burden. In this study, we describe a reflexive mapping exercise to identify the behaviour change strategies undertaken in each of these projects.MethodsUsing the Behaviour Change Wheel framework, each team rated the capability, opportunity and motivation of the various actors who were integral to each project (e.g. community members, non-physician health workers and doctors in projects focussed on service delivery). Teams then mapped the interventions they were implementing and determined the principal policy categories in which those interventions were operating. Guidance was provided on the use of Behaviour Change Wheel to support consistency in responses across teams. Ratings were iteratively discussed and refined at several group meetings.ResultsThere was marked variation in the perceived capabilities, opportunities and motivation of the various actors who were being targeted for behaviour change strategies. Despite this variation, there was a high degree of synergy in interventions functions with most teams utilising complex interventions involving education, training, enablement, environmental restructuring and persuasion oriented strategies. Similar policy categories were also targeted across teams particularly in the areas of guidelines, communication/marketing and service provision with few teams focussing on fiscal measures, regulation and legislation.ConclusionsThe large variation in preparedness to change behaviour amongst the principal actors across these projects suggests that the interventions themselves will be variably taken up, despite the similarity in approaches taken. The findings highlight the importance of contextual factors in driving success and failure of research programmes. Forthcoming outcome and process evaluations from each project will build on this exploratory work and provide a greater understanding of factors that might influence scale-up of intervention strategies.

The effect of changes in visibility and price on fruit purchasing at a university cafeteria in Lima, Peru

OBJECTIVE To determine the effect of increasing fruit visibility, adding information and lowering price on fruit purchasing at a university cafeteria in Lima, Peru. DESIGN Quasi-experimental pilot study of a three-phase stepped intervention. In Phase 1, fruit was displayed >3 m from the point of purchase with no additional information. Phase 2 consisted in displaying the fruit near the point of purchase with added health and price information. Phase 3 added a 33% price reduction. The duration of each phase was 3 weeks and phases were separated by 2-week breaks. Primary outcomes were total pieces of fruit and number of meals sold daily. SETTING A university cafeteria in Lima, Peru. SUBJECTS Approximately 150 people, students and non-student adults, who purchased food daily. Twelve students participated in post-intervention interviews. RESULTS Fruit purchasing doubled from Phase 1 to Phase 3 (P<0·01) and remained significant after adjusting for the number of meals sold daily (P<0·05). There was no evidence of a difference in fruit sold between the other phases. Females purchased 100% of the fruit in Phase 1, 82% in Phase 2 and 67% in Phase 3 (P<0·01). Males increased their purchasing significantly between Phase 1 and 3 (P<0·01). Non-student adults purchased more fruit with each phase (P<0·05) whereas students did not. Qualitatively, the most common reason for not purchasing fruit was a marked preference to buy unhealthy snack foods. CONCLUSIONS Promoting fruit consumption by product placement close to the point of purchase, adding health information and price reduction had a positive effect on fruit purchasing in a university cafeteria, especially in males and non-student adults.

Delivery of Type 2 diabetes care in low- and middle-income countries: lessons from Lima, Peru.

The health systems response is crucial to addressing the increasing burden of diabetes, particularly that affecting low‐ and middle‐income countries. This study aims to assess the facilitators and barriers that help or hinder access to care for people with diabetes in Peru.

Characteristics Associated With Antihypertensive Treatment and Blood Pressure Control: A Population-Based Follow-Up Study in Peru

BACKGROUND Over one-quarter of the worlds adult population has hypertension, yet achieving adequate treatment or control targets remains a challenge. OBJECTIVE This study sought to identify, longitudinally, characteristics associated with antihypertensive treatment and blood pressure (BP) control among individuals with hypertension. METHODS Data from individuals enrolled in the population-based CRONICAS Cohort Study (adults ≥35 years, living in 4 different rural/urban and coastal/high-altitude Peruvian settings) with hypertension at baseline were used. Antihypertensive treatment and BP control were assessed at baseline and at 15 months. Multinomial logistic regressions were used to estimate relative risk ratios (RRR) and 95% confidence intervals (95% CI) of factors associated with antihypertensive treatment and BP control at follow-up. RESULTS At baseline, among 717 individuals with hypertension (53% women, mean age 61.5 ± 12.4 years), 28% were unaware of their hypertension status, 30% were aware but untreated, 16% were treated but uncontrolled, and 26% were treated and controlled. At follow-up, 89% of unaware and 82% of untreated individuals persisted untreated, and only 58% of controlled individuals remained controlled. Positive predictors of receiving treatment and being controlled at follow-up included age (RRR: 0.81; 95% CI: 0.73 to 0.91 for every 5 years) and family history of a chronic disease (RRR: 0.53; 95% CI: 0.31 to 0.92 vs. no history); whereas Puno rural site (RRR: 16.51; 95% CI: 1.90 to 143.56 vs. Lima) and male sex (RRR: 2.59; 95% CI: 1.54 to 4.36) were risk factors. Systolic BP at baseline (RRR: 1.27; 95% CI: 1.16 to 1.39 for every 5 mm Hg) and male sex (RRR: 1.75, 95% CI: 1.02 to 2.98) were risk factors for being treated but uncontrolled at follow-up. CONCLUSIONS Large gaps in treatment of hypertension were observed. Targeting specific populations such as men, younger individuals, or those without family history of disease may increase coverage of antihypertensive treatment. Also, targeting male individuals or those with higher systolic BP could yield better rates of BP control in the short term.

Applying the triangle taste test to assess differences between low sodium salts and common salt: Evidence from Peru

Background In resourced-constrained settings, daily cooking practices are still the norm. Replacing sodium in regular salt to produce potassium-enriched salts are potential alternative routes to reduce sodium intake, paired with the benefit associated with potassium intake. This change would likely have effects on palatability and taste of prepared foods, yet a threshold to discriminate sensorial changes can be determined. The main goal of this study was to assess if the use of potassium-enriched salt substitutes lead to perceived differences in taste utilizing a sensory discrimination test. Methods and Results A triangle taste test was conducted and participants were offered samples of cooked rice prepared with different salts. The only ingredient that differed in the preparation was the salt used: 100%NaCl (regular salt) and salts where sodium was replaced by 50%, 33% or 25% KCl (potassium-enriched salt). Comparisons were carried out according to the minimum number of correct judgments. A total of 156 subjects, 49% males, mean age 41.0 years (SD±15.5) years, participated in the study. Samples using 25% potassium-enrichment were indistinguishable in terms of taste from regular salt, whereas samples with 33% and 50% potassium-enrichment were distinguishable. Results were consistent when stratified by sex and age. Less than 10% of participants attributed the differences to bitterness or metallic flavor. Conclusions The 25% potassium-enriched salt is indistinguishable from regular salt. These findings suggest a potential to achieve sodium intake reduction strategies in cooking practices by substituting regular salt with potassium-enriched salt without affecting palatability.

Health systems research for policy change: lessons from the implementation of rapid assessment protocols for diabetes in low- and middle-income settings

BackgroundAs many challenges exist for access to diabetes care in developing countries, the International Insulin Foundation developed a Rapid Assessment tool and implemented this approach to identify barriers to care and propose concrete recommendations for decision makers. The objective of this paper is to identify the factors that contributed to informing and influencing policymakers with regards to this work.MethodsA documentary review comprised Stage 1. Stage 2 used an online questionnaire to gain insight from users of the Rapid Assessment results. Based on Stages 1 and 2, Stage 3 comprised in-depth interviews with a total of nine individuals (one individual each from the six participating countries; two individuals from the World Health Organization; one “Global Diabetes Advocate”). Interviews were analyzed based on a list of themes developed from Stage 2.ResultsStage 1 led to the identification of various types of documents referring to the results. The online questionnaire had a response rate of 33%. Respondents directly involved in the assessment had a “Good” or “Very Good” appreciation of most aspects and scored these higher than those not directly involved. From the interviews, formalized methods and close collaboration between the international team and local partners were strengths. Trust and a relationship with local partners were also seen as assets. All stakeholders valued the results and the credibility of the data generated. Local partners felt that more could have been done for dissemination.ConclusionThis study shows the importance of specific results from the different assessments. In addressing complex issues having external experts involved was seen as an advantage. The uptake of results was due to the credibility of the research which was influenced by a mix of the people involved, past assessments, trusted local partners, and the use of the results by knowledge brokers, such as the World Health Organization. Through these brokers, others gained ownership of the data. The methods used and the fact that this data was grounded in a local context also reinforced its value. Despite limitations, this study offers a unique perspective where a similar research approach was taken in six countries.

Building a Platform for Translational Research in Chronic Noncommunicable Diseases to Address Population Health Lessons From NHLBI Supported CRONICAS in Peru

The CRONICAS Centre of Excellence in Chronic Diseases, based at Universidad Peruana Cayetano Heredia, was created in 2009 with support from the U.S. National Heart, Lung, and Blood Institute (NHLBI). The vision of CRONICAS is to build a globally recognized center of excellence conducting quality and innovative research and generating high-impact evidence for health. The centers identity is embedded in its core values: generosity, innovation, integrity, and quality. This review has been structured to describe the development of the CRONICAS Centre, with a focus on highlighting the ongoing translational research projects and capacity-building strategies. The CRONICAS Centre of Excellence is not a risk-averse organization: it benefits from past experiences, including past mistakes, and improves upon them and thus challenges traditional research approaches. This ethos and environment are key to fostering innovation in research.

Association between sleep difficulties as well as duration and hypertension: is BMI a mediator?

Sleep difficulties and short sleep duration have been associated with hypertension. Though body mass index (BMI) may be a mediator variable, the mediation effect has not been defined. We aimed to assess the association between sleep duration and sleep difficulties with hypertension, to determine if BMI is a mediator variable, and to quantify the mediation effect. We conducted a mediation analysis and calculated prevalence ratios with 95% confidence intervals. The exposure variables were sleep duration and sleep difficulties, and the outcome was hypertension. Sleep difficulties were statistically significantly associated with a 43% higher prevalence of hypertension in multivariable analyses; results were not statistically significant for sleep duration. In these analyses, and in sex-specific subgroup analyses, we found no strong evidence that BMI mediated the association between sleep indices and risk of hypertension. Our findings suggest that BMI does not appear to mediate the association between sleep patterns and hypertension. These results highlight the need to further study the mechanisms underlying the relationship between sleep patterns and cardiovascular risk factors.