Research Article: Trends in In-Hospital Mortality among Patients with Stroke in China

Date Published: March 20, 2014

Publisher: Public Library of Science

Author(s): Qian He, Cheng Wu, Hong Luo, Zhi-Yong Wang, Xiu-Qiang Ma, Yan-Fang Zhao, Jian Lu, Chun Xiang, Ying-Yi Qin, Shun-Quan Wu, Fei-Fei Yu, Jia He, Alice Y. W. Chang.

http://doi.org/10.1371/journal.pone.0092763

Abstract

The incidence and burden of stroke in China is increasing rapidly. However, little is known about trends in mortality during stroke hospitalization. The objectives of this study were to assess trends of in-hospital mortality among patients with stroke and explore influence factors of in-hospital death after stroke in China.

109 grade III class A hospitals were sampled by multistage stratified cluster sampling. All patients admitted to hospitals between 2007 and 2010 with a discharge diagnosis of stroke were included. Trends in in-hospital mortality among patients with stroke were assessed. Influence factors of in-hospital death after stroke were explored using multivariable logistic regression.

Overall stroke hospitalizations increased from 79,894 in 2007 to 85,475 in 2010, and in-hospital mortality of stroke decreased from 3.16% to 2.30% (P<0.0001). The percentage of severe patients increased while odds of mortality (2010 versus 2007) decreased regardless of stroke type: subarachnoid hemorrhage (OR 0.792, 95% CI = 0.636 to 0.987), intracerebral hemorrhage (OR 0.647, 95% CI = 0.591 to 0.708), and ischemic stroke (OR 0.588, 95% CI = 0.532 to 0.649). In multivariable analyses, older age, male, basic health insurance, multiple comorbidities and severity of disease were linked to higher odds of in-hospital mortality. The mortality of stroke hospitalizations decreased likely reflecting advancements in stroke care and prevention. Decreasing of mortality with increasing of severe stroke patients indicated that we should pay more attention to rehabilitation and life quality of stroke patients. Specific individual and hospital-level characteristics may be targets for facilitating further declines.

Partial Text

Stroke is one of the leading causes of death and disability throughout the world [1], responsible for 4.4 million (9%) of the total 50.5 million deaths each year [2]. The incidence and burden of stroke in China is increasing rapidly over time just like in other developing countries. About 2 million people of all ages suffer a new stroke, and 15 million stroke-related deaths occur in each year [3]. It is now becoming the first leading cause of death in China [1]. Mortality of stroke at discharge significantly increased with age, with 1.15%, 1.46%, 3.31%, and 7.63% in-hospital mortality according to age group (≤45,46–65,66–79, ≥80 years old) respectively, and the very old patients had the worst outcomes even after adjusted by prognostic factors[4]. Now, demographic ageing is occurring at an unprecedented rate worldwide; the proportion of Chinese aged 65 and over will increase from 4% in 2000 to 14% by 2025, amounting to 200 million old people [5]. Aging may also result in an increased risk for stroke [6], which produces more and more burden on society and families [1]. It becomes very urgent to understand the trend of stroke prognosis. However, recent information about in-hospital mortality trends after stroke hospitalization is lack in China, though historical and risk factors of mortality after stroke have been identified in various studies including clinical trials, community-based studies, and voluntary registries[4], [7]. With population aging, the health reform was deepened and stroke prevention, treatment and rehabilitation care were promoted continually. Knowledge of in-hospital deaths after stroke may be helpful for knowing the “real-world” and interface of challenges in optimizing overall premorbid health status, stroke prevention, acute stroke treatment, and acute general medical care at the individual, hospital, and health system levels [7].

Overall, stroke hospitalizations increased from 79 894 in 2007 to 85 475 in 2010 in the 109 grade III class A hospitals, whereas overall percentage of stroke hospitalizations that resulted in death decreased from 3.16% to 2.30% (P<0.0001). Over these years, the mortality of stroke inpatients declined steadily, a trend generally seen across stroke types (Figure 1). Table 1 shows the summary for demographic, clinical, and regional factors for each stroke types. From 2007 to 2010, there was a modest but significant increase in age for SAH (P = 0.0054) and IS (P<0.0001), but not for ICH (P = 0.2572). And compared with 2007, there were more males in 2010 for IS (P = 0.0211) but not for SAH or ICH (P = 0.8438 or 0.2562). During these years, primary payer changed significantly for all stroke types (P<0.0001), and there were more patients who paid by basic health insurance while fewer self-payment. The CCI became less by year (P<0.0001), and the proportion of severe status was increased (P<0.0001). The number of inpatient increased in north for SAH (P<0.0001), west for ICH (P<0.0001), south and west for IS (P<0.0001). The LOS of IS decreased (P<0.0001) while ICH increased (P = 0.0010), and the change of SAH was not significant. This analysis of proportions of in-hospital mortality after stroke from 2007 to 2010 in China showed that deaths during stroke hospitalization have lessened significantly over time and since 2008 the decline has been steady and continuous, probably mainly reflecting improvements in hospital care after occurrence of a stroke. The trend of decrease in the percentage of stroke hospitalizations resulting in death is consistent with the observational study from the Sino-MONICA-Beijing from 1984 to 2004 [10] and the crude mortality of cerebrovascular disease from the fourth health service survey in China [11]. The proportion of IS subtype were the largest, followed by ICH and SAH in the hospitals, and these data are generally in accordance with the incidence of stroke in the survey based on community population and the China National Stroke Registry (CNSR) from 2003-2008 in China [12]–[15]. And the proportion of male was higher than female in IS and ICH,which was similar with other studies [7], [12], [15], while the proportion of female was higher than male in SAH, which was similar with Beijing and Shanghai in China from 1991–2000 [16]. The median age was 68 years old among IS patients while less than 60 years old among ICH and SAH patients, and age difference among subtypes also appeared in some community population [13]. There was a good representativeness for stroke patients because of the similar distribution of subtype, gender and age with the observational studies based on community population and CNSR. This study showed that the mortality decreased from 3.16% in 2007 to 2.30% in 2010 (SAH: form 6.28% to 5.04%, ICH: 9.73% to 6.52%, IS: from 2.48 to 1.47%) while the number of patients increased from 79 894 to 85 475. The decrease trend was also found in the United States (SAH: from 26.90% in 1997–1998 to 23.80% in 2005–2006, ICH: from 30.47% to 28.23%, IS: from 9.76% to 8.78%) [7] and in Germany (from 11.9% in 2005 to 9.5% in 2010) [17]. The in-hospital mortality in this study was nearly equal to the data from the China National Registry [18], but lower than Germany and the United States. There may be some reasons. Firstly, the age of patients in this study was younger (this study: 65 vs. Germany: 73 years old). Secondly, the proportion of ICC≥4 which reflects severe level of stroke was very low compared to America (this study in 2007 vs America in 2005–2006: SAH 0.25 vs 10.2, ICH 0.65 vs 24.3, IS 1.44 vs 29.4). Thirdly, patients were earlier transferred to smaller regional hospitals or home. Fourthly, repetitive admission would decrease the mortality. The decreasing of mortality in the United States was likely driven by revascularization strategies among ischemic strokes and better acute stroke care in addition to prevention of stroke [7]. Some health reform strategy and mass approaches on decreasing mortality were also adopted in China including stroke prevention, various unconventional local therapeutic traditions, and several national guidelines on stroke prevention and treatment [11], [19], [20].   Source: http://doi.org/10.1371/journal.pone.0092763