Disparities Abound in Chinese Heart Attack Care

Continued quality improvement in acute MI may be possible in the U.S. given lessons learned from another country with major geographic and other disparities in acute MI care and mortality: China.

Rural hospitals and those with fewer resources showed opportunities for improved care in China, according to findings from two registries now published online in JAMA Network Open.

“Many researchers believe that we have solved the STEMI [ST-segment elevation MI] problem, but the improvement in mortality has plateaued and we have made very little progress in reperfusion times for patients transferred from a non-PCI [percutaneous coronary intervention] center or outcomes for those with out-of-hospital cardiac arrest or cardiogenic shock,” wrote Timothy Henry, MD, of The Christ Hospital, Cincinnati, and James Jollis, MD, of Duke University School of Medicine in Durham, North Carolina, in an accompanying commentary.

The two studies suggest the U.S. still has a lead over China in acute MI care — but will it be able to keep it? The U.S. has been hurt by a fracturing of the national acute MI registry into multiple competing registries, which poses challenges to regional collaboration and quality improvement, Henry and Jollis suggested.

Meanwhile, they wrote, “China has rapidly embraced the best quality improvement models of the U.S.” and is even poised to surpass the collaborative systems of care in the States.

Geographic Variation

China saw persistent regional variations in the use of reperfusion and guideline-recommended medical therapy, one group reported from registry data.

Despite the launch of national health care reform in 2009, hospitals in the country’s center were 17% less likely to provide MI treatments to eligible patients than centers in western areas in 2011-2015 (adjusted OR 0.83, 95% CI 0.76-0.91), according to Yingling Zhou, MD, PhD, of Guangdong Provincial People’s Hospital.

“In the present study, we observed significant differences in the use of guideline-recommended treatments across China, with hospitals in the Western region having the best performance, particularly for clopidogrel [Plavix], ACEIs/ARBs [angiotensin-converting enzyme inhibitors/angiotensin receptor blockers], and statins,” the research group said.

Zhou’s team noted that the western region is the least economically developed region in China and has been subject to special government investment in public health starting in the year 2000.

Eastern China also improved processes of MI care from 2001-2006 to 2011-2015.

Across the board, use of guideline-recommended treatments increased from 2001-2006 to 2011-2015, and there was some improvement in care variation, study authors said.

“However, care delivery remains suboptimal and disparities remained across China when compared with that in the United States and United Kingdom where reperfusion therapy, β-blockers, and ACEIs/ARBs are used at much higher rates. Additional measures should be taken to further narrow regional care disparity across the country,” Zhou and colleagues urged.

Their cross-sectional study was based on the Patient-Centered Evaluative Assessment of Cardiac Events–Retrospective AMI project. A random sampling yielded 27,046 patients hospitalized for acute MI at 153 hospitals across China.

The country was divided into three geographic regions: eastern, central, and western. There were marked regional variations in patient and hospital characteristics.

Risk of in-hospital mortality fell across all regions. However, the central region had fewer patients die in-hospital and within 5 days of admission (numerically in 2001-2006 and significantly in 2011-2015), despite the lower adherence to guideline-recommended care. The geographic variation in mortality did not change over time.

Zhou and colleagues suggested that “patients in the Central region may have already had lower risk of poor outcomes at presentation.”

Meanwhile, western hospitals may have had worse mortality rates despite better guideline-recommended treatment delivery due to the lesser availability of cardiac catheterization laboratories.

The study’s observational and retrospective nature left room for residual confounding despite statistical adjustment. Zhou’s team also cautioned that the dataset lacked information on key variables such as postdischarge outcomes and timeliness of reperfusion.

Disparities by Hospital Tier

For STEMI patients, higher-tier hospitals in China were associated with better in-hospital mortality rates and were more likely to provide reperfusion therapy, another registry showed.

The three tiers of public hospitals in China reported progressively more in-hospital mortality: 3.1% for province-level hospitals (highest tier), 5.3% for prefecture-level hospitals (mid-tier), and 10.2% for county-level hospitals (lowest tier; P=0.04), according to Yuejin Yang, MD, PhD, of Fuwai Hospital, Chinese Academy of Medical Science and Peking Union Medical College, and colleagues.

“The higher mortality rate in county-level hospitals was associated with patients being in more critical condition, lower use of reperfusion therapy, and lack of advanced hospital facilities, such as CCUs [cardiac-coronary care units] and catheterization laboratories,” the authors found.

“Moreover, the odds of in-hospital death remained higher even after adjustment for these factors, implying that other immeasurable factors, such as insufficient capabilities in clinical expertise, also likely contribute to the much higher mortality in lower level hospitals,” they added.

Additionally, hospital tier corresponded with use of:

• Reperfusion therapy (69.4% for province-level, 54.3% for prefecture-level, 45.8% for county-level; P<0.001 for trend)
• Perfusion therapy in eligible patients admitted within 12 hours of symptom onset (88.6% vs 80.1% vs 72.6%, respectively; P<0.001 for trend)
• Primary PCI within 12 hours in eligible patients (83.8% vs 61.5% vs 31.6%, respectively; P<0.001 for trend)

Better access to timely reperfusion would reduce the gap between low- and high-level hospitals, the investigators said.

In the registry, reported reasons for not receiving reperfusion therapy included patient (or family member) refusal because of concerns about complications, patient’s finances, physician’s decision, and unclear diagnosis.

“These insights provide implications for China as well as other developing countries as a world opportunity to narrow gaps and variations in the care and outcomes of patients with acute MI,” according to Yang’s team.

The study was based on the China Acute Myocardial Infarction Registry, which included 12,695 STEMI patients admitted directly to 108 hospitals in mainland China in 2013-2014.

Overall, just 72.0% of patients arrived at the hospital within 12 hours after symptom onset, and 14.1% of patients used ambulances.

“The possible reasons for this are thought to be mainly patients’ being unaware of their acute MI and lack of information on [EMS] performance. Furthermore, [emergency services] are still underdeveloped and inconvenient in China, especially in rural and remote areas,” Yang and colleagues noted.

Yet treatment delays happened even after patients arrived at the hospital: low rates of meeting door-to-needle and door-to-balloon time goals were seen in all three tiers.

Like the geographic variation study, the present study was limited by its observational and retrospective nature. The dataset also did not include all hospitals in China.