High HF burden in Asia: SEA has youngest patients, worst outcomes
The burden of heart failure (HF) in Asia is high compared with the US and Europe, with Southeast Asia (SEA) having the highest HF prevalence vs other Asian regions combined, and the youngest patients having the worst outcomes, according to data presented at AFCC 2018.
The prevalence of HF in SEA is 9 million, surpassing the rates in China (4 million), India (1.3–4.6 million), and Japan (1 million), and even the US (6 million), noted Professor Carolyn Lam from the National Heart Centre Singapore. Collectively, the Asian numbers could top the European HF prevalence of 15 million, she added.
Age-wise, the Asian-HF* Registry reflected an average age of 60 and 68 years for HFrEF** and HFpEF***, respectively, which are lower than the US (70 and 74 years, respectively) and European registries (64 and 69 years, respectively). [Eur J Heart Fail 2013;15:928-936]
“The fact that the average age of HFrEF [in Asia] is 60 is [alarming … as this means that] at 60, you have end organ failure. This is something we really need to pay attention to,” highlighted Lam.
Moreover, although the Asian cohort was younger, they had a similar or higher risk factor burden (coronary artery disease [CAD], hypertension, and type 2 diabetes [T2D]) than their US or European counterparts.
Risk factor distribution across the Asian region was higher in SEA (58.8, 64.2, and 49.3 percent for CAD, hypertension, and T2D, respectively) compared with South Asia (51.1, 37.9, and 37.1 percent, respectively) and Northeast Asia (38.2, 48.1, and 31.8 percent, respectively). [Eur Heart J 2016;37:3141-3153]
Regarding HFpEF – which is more common in slightly older individuals with more comorbidities, SEA still tops the charts in terms of comorbidity burden which, according to Lam, translates to even worse outcomes. [Eur J Heart Fail 2018;doi:10.1002/ejhf.1227]
Of note is the young HFpEF phenotype in Asia wherein the average age is <55 years, as opposed to the average of >80 years in the US and Europe. Compared with age-matched controls, young patients with HFpEF had a threefold higher mortality rate and twofold higher hypertrophy rate. [Circulation 2018;doi/abs/10.1161/CIRCULATIONAHA.118.034720?af=R&]
Diabetes and HF in Asia
T2D is highly prevalent in Asians with HFrEF, with Singapore having the highest prevalence (approximately 60 percent), noted Lam. Moreover, individuals with T2D have a worse 1-year composite outcome vs those without diabetes even after adjusting for confounding factors (hazard ratio [HR], 1.37; p<0.001).
As T2D impacts more women with HF than men, it subsequently increases their predisposition to CKD (adjusted odds ratio [adjOR], 1.74 vs adjOR, 1.36; pinteraction=0.009) and concentric left ventricular remodelling (pinteraction=0.003). Women with T2D also have worse composite outcomes at 1 year compared with men (HR, 2.01 vs HR, 1.33; pinteraction=0.002).
Asian women with HF are also more prone to have the lean diabetic phenotype – which represents the “skinny yet diabetic” group commonly found in Singapore, Malaysia, and Hong Kong, noted Lam. It is important to focus on this as the lean diabetic HFpEF phenotype had the worst outcomes out of all the HF comorbidity clusters in Asia. [PLoS Med 2018;doi:10.1371/journal.pmed.1002541]
Worst outcomes in low BMI, high WHtR
An interesting paradox was observed between body mass index (BMI) and waist-to-height ratio (WHtR), wherein a higher BMI translated to better composite outcomes whereas for WHtR, it is the complete opposite, noted Lam. “If you have HF, the more obese you are, [the more] you’ll do better … However, a higher WHtR [even with low BMI] translates to worse outcomes.”
Given these findings, having a low BMI with a big waist – which is relatively common in Asia – would be the worst body morphology for individuals with HF, said Lam.
Underutilization of medical therapies, device
Lam was quick to point out that Asia is “not doing very well” in terms of HF management, and one reason is the underutilization of guideline-directed medical therapies. “Although ACEi/ARB# uptake [in Asia] is more than 75 percent, only 17 percent achieved guideline-directed doses … With β-blockers, it’s even worse, [as] only 12.5 percent achieved guideline-directed doses,” said Lam. Nonetheless, adjusted analysis showed that any dose of ACEi/ARB or β-blockers is better than none, she added.
Despite the reduced risk of all-cause mortality (HR, 0.71) and sudden cardiac death (HR, 0.33) associated with implantable cardioverter-defibrillators (ICDs), there is a low rate of device usage in Asia, said Lam, as only 12 percent of individuals who need an ICD have one. [Circ Cardiovasc Qual Outcomes 2017;doi:10.1161/CIRCOUTCOMES.116.003651]
Younger patients may not be keen on having an ICD thinking they do not need it, Lam pointed out. “[Therefore,] we need to do a better job [in encouraging the use of ICDs] … especially because [the Asian] population is younger,” she said.
“[Overall, there is a] big burden of HF in Asia … [and there are great] opportunities for us to improve [patient] outcomes … The most important thing we can do at the moment is [HF] prevention in high-risk individuals,” concluded Lam.