The burden of hypertension in Cuba
Authors: Norm R C Campbell, Yamile Valdes Gonzalez, Pedro Ordunez
Journal: The Lancet Public Health (2019)

Increased blood pressure is the leading risk factor for death worldwide, leads to the greatest disease burden in low-income to middle-income countries (LMICs), and prevalence is increasing.1Campbell NR Khalsa T Lackland DT et al.High blood pressure 2016: why prevention and control are urgent and important. The World Hypertension League, International Society of Hypertension, World Stroke Organization, International Diabetes Foundation, International Council of Cardiovascular Prevention and Rehabilitation, International Society of Nephrology.J Clin Hypertens (Greenwich). 2016; 18: 714-717Crossref PubMed Scopus (29) Google Scholar, 2Mills KT Bundy JD Kelly TN et al.Global disparities of hypertension prevalence and control: a systematic analysis of population-based studies from 90 Countries.Circulation. 2016; 134: 441-450Crossref PubMed Scopus (1743) Google Scholar By contrast, the age-adjusted prevalence of hypertension is decreasing in high-income countries.2Mills KT Bundy JD Kelly TN et al.Global disparities of hypertension prevalence and control: a systematic analysis of population-based studies from 90 Countries.Circulation. 2016; 134: 441-450Crossref PubMed Scopus (1743) Google Scholar The global data on hypertension are daunting: four in ten people older than 25 years have hypertension, fewer than 50% are aware of their status, and only 14% have controlled blood pressure.2Mills KT Bundy JD Kelly TN et al.Global disparities of hypertension prevalence and control: a systematic analysis of population-based studies from 90 Countries.Circulation. 2016; 134: 441-450Crossref PubMed Scopus (1743) Google Scholar Increased global attention will improve hypertension control. WHO has a voluntary target for countries to reduce raised blood pressure by 25% by 2025. Leading multiple organisations, WHO and the US Centers for Disease Control and Prevention have also developed supporting tools to aid countries to reduce the burden of hypertension.3WHOHEARTS: technical package for cardiovascular disease management in primary health care. World Health Organization, Geneva2016Google Scholar In addition, with more than US$200 million of philanthropic funding, the Resolve to Save Lives global intervention is focused on controlling hypertension.4Frieden TR Jaffe MG Saving 100 million lives by improving global treatment of hypertension and reducing cardiovascular disease risk factors.J Clin Hypertens (Greenwich). 2018; 20: 208-211Crossref PubMed Scopus (57) Google Scholar In The Lancet Public Health, Nurys Armas Rojas and colleagues5Armas Rojas N Dobell E Lacey B et al.Burden of hypertension and associated risks of cardiovascular mortality in Cuba: a prospective cohort study.Lancet Public Health. 2019; (published online Jan 22.)http://dx.doi.org/10.1016/S2468-2667(18)30210-XPubMed Scopus (20) Google Scholar report a high-quality, long-term cohort study that adds to the story of the burden of hypertension. In Cuba, which is an LMIC, they surveyed a cohort of 136 111 residents aged 35–79 years in 1996–2002. In face-to-face interviews during household visits, participants were ask about health-related behaviours and medical history, and blood pressure was measured. In 2006–08, a subset of 23 114 participants was resurveyed. The baseline prevalence of hypertension was 34%, which is on a par with the global average of 31%.2Mills KT Bundy JD Kelly TN et al.Global disparities of hypertension prevalence and control: a systematic analysis of population-based studies from 90 Countries.Circulation. 2016; 134: 441-450Crossref PubMed Scopus (1743) Google Scholar Of people who had hypertension, 67% were aware of being diagnosed and 51% were taking antihypertensive drugs. These values are similar to the averages for high-income countries (67% and 56%, respectively).2Mills KT Bundy JD Kelly TN et al.Global disparities of hypertension prevalence and control: a systematic analysis of population-based studies from 90 Countries.Circulation. 2016; 134: 441-450Crossref PubMed Scopus (1743) Google Scholar Among respondents with diagnosed hypertension, three-quarters were receiving treatment, although hypertension was controlled in only 36% of treated patients. Thus, the overall rate of control was 18% among all people with hypertension. This value is between the averages for high-income countries and LMICs (8% and 28%, respectively).2Mills KT Bundy JD Kelly TN et al.Global disparities of hypertension prevalence and control: a systematic analysis of population-based studies from 90 Countries.Circulation. 2016; 134: 441-450Crossref PubMed Scopus (1743) Google Scholar Two-thirds of participants with hypertension who were receiving treatment were taking only one medication, which probably explains why the control-to-treatment ratio was lower than expected. Of note, control of blood pressure increased from 36% to 59% among resurveyed participants who were treated. Overall, uncontrolled blood pressure accounted for about 20% of premature excess cardiovascular deaths. However, about half of blood-pressure-related outcomes are associated with blood pressure that is increased but remains below the threshold for hypertension.1Campbell NR Khalsa T Lackland DT et al.High blood pressure 2016: why prevention and control are urgent and important. The World Hypertension League, International Society of Hypertension, World Stroke Organization, International Diabetes Foundation, International Council of Cardiovascular Prevention and Rehabilitation, International Society of Nephrology.J Clin Hypertens (Greenwich). 2016; 18: 714-717Crossref PubMed Scopus (29) Google Scholar Hence, the overall burden of blood-pressure-related premature deaths in Cuba is probably closer to 40%. Cuba has a well-educated population, a very strong primary-care system with high capacity, universal coverage and access, affordable medications, and robust clinical registries. These features allow researchers to do high-quality clinical and epidemiological studies that would be difficult to replicate in other LMICs.5Armas Rojas N Dobell E Lacey B et al.Burden of hypertension and associated risks of cardiovascular mortality in Cuba: a prospective cohort study.Lancet Public Health. 2019; (published online Jan 22.)http://dx.doi.org/10.1016/S2468-2667(18)30210-XPubMed Scopus (20) Google Scholar The cohort in the study of Armas Rojas and colleagues, although not randomly selected from the overall population, shared similar characteristics with Cubans overall and, therefore, is likely to reflect the national situation. By contrast, the unique socioeconomic environment of Cuba, however, also limits the ability to generalise this cohort study to most LMICs. In many ways, the Cuban cohort findings are not surprising. As noted by Armas Rojas and colleagues, hypertension control has been a priority in Cuba. A survey in the city of Cienfuegos indicated a high rate of hypertension control in 2001–02.6Ordunez-Garcia P Munoz JLB Pedraza D Espinosa-Brito A Silva LC Cooper RS Success in control of hypertension in a low-resource setting: the Cuban experience.J Hypertens. 2006; 24: 845-849Crossref PubMed Scopus (46) Google Scholar Hypertension control rates in Cuba have probably exceeded those reported by Armas Rojas and colleagues because their latest data were about 10–12 years old and control was increasing at that time. Cuba has collaborated with the Pan American Health Organization and other organisations, including Resolve to Save Lives, to implement system changes to enhance blood-pressure control.7Patel P Ordunez P DiPette D et al.Improved blood pressure control to reduce cardiovascular disease morbidity and mortality: the Standardized Hypertension Treatment and Prevention Project.J Clin Hypertens (Greenwich). 2016; 18: 1284-1294Crossref PubMed Scopus (81) Google Scholar These changes have included widespread implementation of community engagement with World Hypertension Day, task sharing to engage multiple health-care professionals in screening and management of hypertension, development of a simple diagnostic and therapeutic algorithm, and a registry with performance reporting. The interventions have already been successfully introduced in two pilot sites, and upscale of the initiative to the national level has started. To further improve hypertension control, Cuba needs to update its formulary of antihypertensive drugs to include those that are long acting and available in fixed dose combinations. The proportion of people with hypertension being treated with multiple medications should also be increased. Challenges for improving health-care delivery in LMICs, including for blood pressure control, are substantive and include various factors, such as economic changes and natural events. In Cuba, prevalence and incidence of cardiovascular disease and diabetes fell due to long-term economic hardship in the 1990s, but surpassed earlier rates when the economy began to grow again.8Franco M Bilal U Orduñez P et al.Population-wide weight loss and regain in relation to diabetes burden and cardiovascular mortality in Cuba 1980–2010: repeated cross sectional surveys and ecological comparison of secular trends.BMJ. 2013; 346: f1515Crossref PubMed Scopus (118) Google Scholar Cuba's improvements in hypertension control, therefore, should inspire other countries, many of which have higher socioeconomic status. We believe Cuba is poised to be an early example of a major success in controlling hypertension. Potentially, the next reporting cycle of Armas Rojas and colleagues cohort study will show further improved control and reduced blood-pressure-related premature mortality. While we applaud Cuba's success in hypertension control, we note with concern the high prevalence of tobacco use and the lack of a substantive national programme to decrease salt consumption. Tobacco use is the leading risk of death in Cuba and reducing dietary salt will effectively lower the prevalence of hypertension, with both strategies yielding very large returns on investment.9WHOSaving lives, spending less: a strategic response to noncommunicable diseases. World Health Organization, Geneva2018Google Scholar This online publication has been corrected. The corrected version first appeared at thelancet.com/public-health on February 6, 2019 This online publication has been corrected. The corrected version first appeared at thelancet.com/public-health on February 6, 2019 YVG's opinions do not necessarily represent those of the Cuban government. PO is a staff member of the Pan American Health Organization. The author alone is responsible for the views expressed in this publication, and they do not necessarily represent those of the Pan American Health Organization. NRCC has received consultant fees from the Novartis Foundation, has received consultancy fees for advice on accurate blood pressure assessment to Midway Corporation, and is an unpaid member of World Action on Salt and Health. The other authors declare no competing interests. Burden of hypertension and associated risks for cardiovascular mortality in Cuba: a prospective cohort studyIn this Cuban population, a third of people had hypertension. Although levels of hypertension diagnosis and treatment were commensurate with those in some high-income countries, the proportion of participants whose blood pressure was controlled was low. As well as reducing hypertension prevalence, improvement in blood pressure control among people with diagnosed hypertension is required to prevent premature cardiovascular deaths in Cuba. Full-Text PDF Open AccessCorrection to Lancet Public Health 2019; 4: e79–80Campbell NRC, Gonzalez YV, Ordunez P. The burden of hypertension in Cuba. Lancet Public Health 2019; 4: e79–80—The following statements should have been included in the disclosure: "YVG's opinions do not necessarily represent those of the Cuban government. PO is a staff member of the Pan American Health Organization. The author alone is responsible for the views expressed in this publication, and they do not necessarily represent those of the Pan American Health Organization." This correction has been made to the online version as of Feb 6, 2019. Full-Text PDF Open Access