In this hospital-based prospective cohort study from Da Nang Hospital in Vietnam, we enrolled 754 stroke patients over one year and observed a 28-day crude mortality of 37%. The proportion of confirmed hemorrhagic strokes was nearly 50%. A number of factors were independently associated with 28-day mortality, the two strongest of which were depressed level of consciousness on presentation and hemorrhagic stroke type. Also, a number of observations about processes of care were worthy of note in that they are different than in many western medical systems and, in some cases, may represent opportunities for evidence-based interventions to improve outcomes.
The 37% 28-day overall mortality observed in this cohort is similar to the mean overall early mortality of 35.7% in population-based studies of strokes from low and middle-income countries during the 1980’s, but higher than the 2000–2008 26.6% early mortality estimate from low and middle-income countries and the 19.8% from high-income countries
. The stroke type specific mortality (20.3 % for ischemic, 51% for hemorrhages) can be compared to the population-based early mortality rates in low and middle-income countries for ischemic stroke at 16.7% (range 13-19%) and ICH at 38.7% (range 30-48%) from 2000–2008
. Our Da Nang hospital-based stroke type specific estimates of mortality are slightly higher in both stroke types, and show the expected higher mortality of patients with hemorrhages over those with ischemic strokes; thus a good portion of the overall increased mortality in our cohort is due to the higher mortality among patients with hemorrhagic stroke. One of the population-based studies with the highest mortality estimate was from Tbilisi, Georgia (classified similar to Vietnam as a lower middle income country by the World Bank
), included patients from 2001–2003 and found ischemic stroke early mortality was 19.2% and ICH 48.4%
. These high estimates were, in part, blamed on “lack of an organized stroke service with specialized stroke units,” which may also be a factor in Vietnam. Hospital-based mortality rates from the United States (US) can be found in reports based on the Get-with-the-Guidelines (GWTG) Stroke quality improvement registry. The in-hospital mortality or discharge to hospice proportions by stroke type in the first million patients was 9.1% for ischemic stroke and 30.7% for ICH, again lower than the 28-day mortality estimate in our Vietnam cohort
. In the fully ascertained population-based samples used for comparison
, patients with less severe strokes are included but are less likely to be represented in hospital-based cohorts because they may simply stay home or see a health care provider without hospitalization. This question of who gets hospitalized may lead to a referral bias in our hospital-based cohort with selection of more severe cases and may be a partial explanation for the Vietnam cohort’s higher mortality compared to the population-based studies. Also, the patients included in the GWTG-Stroke registry are those for whom the stroke ICD-9 code is in the primary position
. In an earlier report-based on administrative stroke data, we showed that patients whose ischemic stroke ICD-9 codes were in non-primary positions (who would thus be excluded from GWTG-Stroke) were much more likely to die by 30 days, 30%, vs. 12.6% for those with a primary position ischemic stroke ICD-9 code
. These GWTG hospital discharge mortality data thus likely underestimate true early mortality in all hospitalized stroke patients.
A number of studies have shown that the proportion of stroke due to ICH is higher in Asian countries
. Older studies from Japan supported a higher proportion of ICH, though as hypertension treatment has increased, this excess has become less apparent
. A review of stroke epidemiology from China notes ICH proportions from more recent studies of 19-48%. One study spanning the years 1986–2000 reported an ICH proportion as high as 55%
[18, 19]. The distribution of stroke types also varies by income level, with double the proportion of ICH documented in middle and low income countries (22%) compared to high income countries (11%)
. Our data from Da Nang, Vietnam is consistent with this literature; we observed that nearly 50% of hospitalized stroke patients had ICH. This is likely related to a high proportion of untreated hypertension in Vietnam. In a parallel study in Da Nang, we found 32.9% of community adults over age 35 to have hypertension, with more than two-thirds of participants unaware of their condition
. Some of this high proportion of hemorrhagic stroke may also have been related to structural abnormalities such as vascular malformations or tumors, but neither contrast CT nor CT angiography were part of the local standard of care, so these conditions were not identified.
The independent predictors of 28-day mortality in our stroke cohort are broadly consistent with many previous studies. The most powerful single patient characteristic was “disturbed level of consciousness” at the time admission to the hospital, a marker of a very severe stroke; speech disturbance was also associated with mortality, but weakness seemed to have a paradoxical inverse association. This latter finding may represent an ascertainment bias, whereby patients with the most severe strokes (and likely depressed level of consciousness), were not able to cooperate with a neurologic exam enough to demonstrate weakness. In a recent study of hospitalized stroke patients from Fortaleza, Brazil, depressed level of consciousness was also the strongest independent predictor or poor outcome at discharge, other significant predictors being age and pre-stroke disability
. Stroke severity is consistently the most powerful predictor of stroke outcome, as has been known scientifically for decades and by clinicians since ancient times
. Pre-stroke disability is consistently reported as an important prognostic indicator and was also found to be the case in our patients from Vietnam.
A Stroke Unit is defined as “a discrete area in the hospital that is staffed by a specialist stroke multidisciplinary team. It has access to equipment for monitoring and rehabilitating patients. Regular multidisciplinary team meetings occur for goal setting.”
. Stroke Units are a highly evidence-based way to improve outcomes after stroke
. Systematic meta-analyses show an estimated 14% reduction in the odds of death at ~1 year follow up and an 18% reduction in the odds of death or dependency
. The experience with Stroke Unit care in Vietnam is limited, with fewer than 10 Stroke Units reported in the country in 2007
. A major limitation to the formation of more stroke units, and potentially improved outcomes, may be the limited availability of stroke specialists; while ICU physicians, cardiologists and general internal medicine doctors traditionally care for these patients, stroke does not appear to be a special focus. These limitations in capacity, resources, infrastructure and training likely contribute to the high mortality. The Da Nang Hospital lacks a formal Stroke Unit, but virtually all stroke patients are admitted to either the ICU or the Cardiology unit. Such a consistent geographic placement of stroke patients suggests that additional training of a focused group of health care providers could lead to “stroke unit” like conditions and greater and more consistent implementation of internationally recognized stroke standards of care.
Carotid endarterectomy (CEA) is a highly evidence-based intervention for prevention of stroke due to high grade symptomatic stenosis
. Carotid ultrasound has been identified as a quality indicator for acute ischemic stroke care, in individuals who would otherwise be eligible for CEA
. The application of carotid ultrasound was low in our ischemic stroke subgroup (1.7%), suggesting a lack of resources for more routine use. Also factoring into this low rate is the lack of a surgeon in Da Nang who can perform CEA, but patients can be transferred to Ha Noi or Ho Chi Minh City if CEA is needed. Similarly, the Fortaleza, Brazil study suggested many care resources are not present in more remote hospitals
. A commentary on the Brazil study suggested there is utility in the reporting of modest results, as they reveal the possibility of improving quality of care as a result
The use of antithrombotic medications (antiplatelet or anticoagulation medications) during hospitalization and prescribed at the time of hospital discharge is a widely accepted standard of care in western countries for ischemic stroke (28). Despite this standard, and even after limiting our assessment to ischemic stroke patients that neither died in hospital nor were discharged home to die, anti-thrombotics were only used in 52% of ischemic stroke patients. This low proportion may in part be appropriate, in that there are a number of valid reasons why some patients may not be able to take antithrombotic agents (e.g. allergy to aspirin, or history of severe bleeding condition), but such exclusions would not likely increase compliance to 100%. Consistent with this suboptimal rate of antithrombotic use are the results from the 2011 PURE study showing use of simple inexpensive medications for patients with a history of cardiovascular disease, including stroke, is low and proportional to country income level
A culturally unique observation was the large proportion of patients “discharged home to die,” as occurred in 15% of ischemic stroke cases and 40% of ICH (Table
2). The general Vietnamese belief holds that people should die at home, where they spent most of their lives, and with family members around and caring for them. If the doctor thinks that the patient has little chance to survive they will inform the family of the situation, and the family makes the final decision to take the patient home
. A series of rituals are performed starting at the time of eminent death to one year after death. As described above, virtually all of the patients discharged to die at home did so within the first day of leaving the hospital. Although Vietnamese hospitals do not currently have formal do-not-resuscitate orders in place, this cultural practice mirrors withdrawal of life sustaining interventions (WLSI) and do-not-resuscitate orders (DNRs) in the US, which account for the majority of deaths in ICH
. In fact, WLSI and DNR orders doubles the risk of death even after adjusting for clinical and radiographic characteristics
. A “self-fulfilling prophecy” may exist if patients with particular clinical or radiographic characteristics are presumed to have a poor outcome, and based on this presumption, life-sustaining interventions are withdrawn or DNR orders are established
[34, 35]. These early care limitations have been shown to independently predict mortality in stroke patients
The strengths of our study are numerous. Patient-level detailed data were collected in a prospective fashion from all stroke patients presenting to Da Nang Hospital, which supplies the vast majority of health care in the area. Only a few patients were lost to follow-up, only a moderate amount of data points were missing, and the use of imputation allowed for inclusion of all patients in analyses. The high level of 28-day follow-up we obtained contrasts to difficulties obtaining these data in previous WHO Stroke STEPS endeavors
. We have demonstrated that collaboration between stroke caregivers in high and low-income countries is feasible and can add to the sparse literature on the processes and outcomes of care in resource-poor settings. Gaps in evidenced-based, and often inexpensive, care for stroke patients were identified and will serve as targets for future interventions that may be generalizable to other resource-poor stroke care settings.
Limitations of our study include the lack of true population-based review of stroke cases; patients with acute stroke not admitted to the hospital were not captured, and so our sample may not be representative of the true stroke burden in Da Nang. Furthermore, we did not conduct a complete assessment of all potentially important risk factors for stroke. Alcohol consumption, for instance, has been shown in several studies to be associated with the risk of hemorrhagic stroke
. Other important risk factors that can be assessed in future studies include physical activity and body mass index. Greater detail about stroke risk factors prior to stroke presentation, and more detail on stroke etiology may allow a better understanding of culturally relevant approaches to stroke prevention. Also, stroke outcomes are often best assessed 3–6 months after stroke, once much of the recovery has occurred.