Pulmonary hypertension in majority countries: opportunities amidst challenges

Abstract

Purpose of review Pulmonary hypertension is a deadly disease, the causes of which vary between geographical regions. Eighty four percentage of the world's population lives in majority countries (also called low-income and middle-income countries), yet data on pulmonary hypertension in these settings are proportionally scarce. This article provides a review of pulmonary hypertension in majority countries, focusing in detail on the most common causes in these regions, and highlights contextual challenges faced. Recent findings Epidemiological data confirms a complex and overlapping array of causes, with pulmonary hypertension because of conditions such as rheumatic heart disease, HIV, schistosomiasis, chronic lung disease and sickle cell disease. Delayed pulmonary hypertension diagnosis remains a concern and is ascribed to a lack of resources and lack of pulmonary hypertension awareness by health professionals. Pulmonary hypertension diagnosis is frequently considered once signs of right heart failure emerge, while echocardiography and right heart catheterization are unavailable in many settings. Accurate data on the prevalence of pulmonary hypertension in many of these regions are needed and could be achieved by establishing and frequent review of national databases where the incident and prevalent pulmonary hypertension cases are captured. Summary There is urgent need for pulmonary hypertension advocacy among clinicians in the primary, secondary and tertiary healthcare sectors of majority countries, and validated noninvasive diagnostic algorithms are needed. Increased awareness and early diagnosis are likely to improve outcomes of pulmonary hypertension patients in these regions, and potentially stimulate locally relevant research.

Pulmonary hypertension in developing countries: Limiting factors in time to diagnosis, specialised medications and contextualised recommendations

“…[17] The latter has long been recognised as a significant challenge in developing countries, where resources are limited. [1] A study conducted in the UK [19] found that almost half of ‘patients did not receive a diagnosis until a year after first experiencing symptoms’. Armstrong et al [19] demonstrated that in the first 12months after patients first noticed symptoms, a definite PH diagnosis was received by 11% of patients who saw only one health professional, while 40% of patients saw four or more health professionals and 9% saw seven or more health professionals before receiving a diagnosis.…”

“… [19] Patients may be seen by a primary healthcare physician for months or years and still not receive the appropriate diagnosis. [1] This challenge is complex and requires intervention. [8] …”

“…Pulmonary hypertension (PH) is defined as a mean pulmonary artery pressure ≥25 mmHg, when measured with right-heart catheterisation. [1] Pathologic triggers (toxins, sheer stress, oxidative stress) cause cells in the pulmonary arterioles to undergo excessive proliferation, leading to the narrowing and obliteration of the vessel lumen, thereby increasing pulmonary artery pressure. [2] The global prevalence of PH is not known, but recent work has demonstrated that PH can no longer be considered a rare disease.…”

“…However, there are several challenges pertaining to PH diagnosis and treatment in developing countries. [1] These include a lack of screening tools, delayed or misdiagnosis, lack of awareness among clinicians and patients, exorbitant costs of medication and the lack of specialised medication. These challenges complicate the fight against PH by preventing a qualitative and quantitative census of PH prevalence (per country) [11 , 12] and impedes the clinical management of the disease.…”

Mice with humanized immune system as novel models to study HIV-associated pulmonary hypertension

“…ART does not cure HIV infection and patients struggle with infectious and non-infectious complications of chronic HIV infection. In patients aging with HIV, low-level viral replication persists within tissues like the lungs, which imposes important challenges to viral eradication after long-term ART and serious co-morbidities due to chronic inflammation (3)(4)(5)(6)(7)(8)(9). Pulmonary vascular cell dysfunction precedes vascular remodeling, which may result in life-threatening Pulmonary Hypertension (PH) depending on the type and degree of the injury at the molecular and cellular levels.…”