The Correlation Between the Length of Stay in Post-Acute Care(PAC) and General and Improvements in Stroke Patients

Background Post-acute care (PAC) is a transitional care following acute medical stage for stroke patients and offering a more intensive rehabilitative program. According to National Health Insurance in Taiwan, only patients encountered acute stroke within one month, under relative stable medical condition and had potential for aggressive rehabilitation could transfer to PAC institution. Stroke patients receive physical, occupational and speech therapy in PAC. However, there’s no research evaluating the effects of PAC for stroke patients ever since the PAC plan inaugurated in Taiwan. Thus, this study aims to investigate whether the duration of hospitalization in PAC correlates to the patients’ improvements. Methods This is a retrospective and single- center study in Taiwan. We collected 193 stroke patients who received acute care at Chi Mei Medical Center, Taiwan during 2014~2017 and recorded their length of stay in PAC. Stroke patients’ functional ability, such as activities of daily living (ADL) function, swallowing ability and so on, as well as their corresponding scales were assessed on the first and last day during PAC hospitalization. Statistical analysis was conducted via SPSS ver21.0. This study was listed on ClinicalTrials.gov(Identification number: NCT03778905). Results The average duration of hospitalization in PAC was 35.01±16.373 days. The longer duration of hospitalization in PAC positively correlates to BI (p=0.000 , R=0.330), BAL(p=0.000 , R=0.461), Gait Speed(p=0.002 , R=0.218), upper sensory function of FMA(p=0.000* , R=0.263) and upper motor function of FMA(p=0.000***, R=0.276) in stroke patients significantly. Conclusion Longer duration of hospitalization in PAC is conducive to enhancing ADL function, advancing balance and coordination, boosting walking speed and augmenting both dexterity and sensory function of upper limb in stroke patients.


Introduction
Post-acute care (PAC) is a transitional care following acute medical stage for stroke patients and offering a more intensive rehabilitative program. According to National Health Insurance in Taiwan, only patients encountered acute stroke within one month, under relative stable medical condition and had potential for better recovery could transfer to PAC institutions. Stroke patients receive physical, occupational and speech therapy in PAC. However, there's no research evaluating the effects of PAC inpatient stays for stroke sufferers ever since the PAC project inaugurated in Taiwan. Thus, this study aims to investigate: Whether the duration of hospitalization in PAC correlates to the stroke patients' improvements?
Methods Design This is a retrospective and single-center study in Taiwan. We collected 305 patients with stroke who received acute care at Chi-Mei Medical Center, Taiwan during 2014~2017 and recorded their length of stays in PAC after the patient discharged from our hospital.
Patients' data and performance were collected by PAC case manager from PAC institutions. The study design was approved by the Institutional Review Board of Chi Mei Medical Center and was listed on ClinicalTrials.gov(Identification number: NCT03778905).

Study Sample and Enrollment
Inclusion criteria of stroke Post-Acute Care(PAC) are modified Rankin scale(MRS) ranging 2~4, acute onset of stroke within 30 days and over 18-year-old. 305 stroke patients eligible for PAC admission were recruited. 3 stroke patients refused PAC admission while 6 stroke patients had second stroke during acute phase. 296 stroke patients successfully transferred to PAC institution but 8 patients ended PAC hospitalization earlier due to stroke or non-stroke disease progression. We scrutinized the rest of 288 stroke patients and excluded 95 stroke patients with incomplete records of functional ability during PAC hospitalization. 193 stroke patients, with completion of PAC hospitalization and intact data of functional ability, were enrolled in our study ( Figure 1). 60.0%(n=117) of stroke patients were male and 39.4%(n=76) were female (Table 1).

Functional Ability and Variables
Among all stroke patients, only 51.8%(n=100) received speech therapy during PAC hospitalization.

Discussion
The PAC program revealed a more economic 2, 3 and better recovery strategy 4  The average length of stay in PAC in our study is 35.01±16.373 days, which is a little longer than previous data of 25.21~34.11 days admitted in PAC for stroke patients in subacute phase 3 . Ischemic stroke accounted for 76.7%(n=148) stroke patients and hemorrhagic type accounted for 23.3%(n=45), which is quite compatible with previous essay indicated in 80% of ischemic stroke and 20% of hemorrhagic stroke in epidemiological prevalence 6 .In our study, stroke patients included 60.6%(n=117) male and 39.4%(n=76) female. Generally, male stroke incidence and prevalence surpassed 33% and 41% than the female 7 .
One essay has shown that speech disorder could be found in 82.37% of stroke patients 8 but in our study only 51.8%(n=100) receiving speech therapy and no positive relations between longer stay in PAC and improvements in CCAT. Dysphagia, on the other hand, were verified in 23% to 50% stroke patients 9 and 99% (N=191) of our stroke patients underwent swallowing training. FOIS was conducted to assess oral intake function and poor oral feeding may contribute to malnutrition in a certain way. Though FOIS and MNA do show benefits for stroke patient after PAC program 5 , both of them do not positively correlate to the duration of hospitalization in PAC in our study simultaneously.
Gait speed had positive correlation with the length of stay in PAC in our study while 6MWT didn't. Usual gait speed is executed with regular distance(5 meters of valid testing, 1 meter for acceleration and 1 meter for deceleration) and recorded the time of walking to acquire walking velocity 10 . On the contrary, 6MWT is executed with regular time of 6 minutes and recorded the distance of walking within the time 11 . Gait speed is viewed as the sixth vital sign to assess general function and capacity of a person 10 and Gait speed was found significantly and independently associated with 6-minute-walk distance in severe chronic lung disease 12 . Both Gait Speed and 6MWT allow patients bring their walking devices during examination but are invalid if the patients need help from other person to accomplish the examination. Both tests mainly base on patients' ambulation by themselves, but 6MWT requires better cardiopulmonary capacity to achieve greater outcome. Thus, 6MWT may not show positive correlation to the length of stay in PAC as Gait speed does, since good cardiopulmonary capacity may not be easily established early in sub-acute phase of stroke.
ADL function is represented with MRS and BI in acute medical center and PAC setting.
Relationship between MRS and BI in stroke patients was investigated in many essays, but there's no consensus for it. Poor outcomes of stroke are viewed as MRS>3 and BI<60 13 . In our study, MRS doesn't reveal significant correlation with the duration of hospitalization in PAC while Barthel index does. This may be elucidated with different measuring categories in these two measurements. MRS basically focus on ambulation and ability to accomplish activity before stroke attack with 0~6 scale. On the other hand, Barthel index mainly aims on the capability to complete various aspects in daily life with 0~100 scale. Previous essay have also pointed out MRS are mainly for global disable assessment and doesn't account for limitation in normal activity of daily life 14 . That is to say, Barthel index is able to reflect small degree improvements of stroke patients and thus leading to significant correlation between its improvements and the length of stay in PAC.
Upper extremities function is evaluated by motor function of FMA and MAL(amount use/ quality) in our study. Current essay indicated more common use of FMA for post-stroke upper extremities function evaluation but international consensus of standard measurement is less established 15 . In our study, FMA showed significant correlation between its improvements and the length of stay in PAC but MAL didn't. It could be explained by the divergent way of examining upper extremities in the two measurements.
Motor function of FMA examines joint movement, i.e. wrist extension, and coordination(finger-to-nose) 16 . Meanwhile, MAL focus on whether the patient could finish certain tasks by their upper extremities, i.e. use a key to open a door by self-reporting 17 .
One essay revealed that FMA is more applicable for multiple impairment of upper extremity while MAL may be influenced by patient's recall and cognition 18 . It takes more coordination and enough muscle power to execute tasks in MAL and thus more rehabilitation is needed after joint movements training. In the sub-acute phase of stroke patients in PAC, the improvements in the motor function of FMA could be manifest easier than MAL and therefore significant correlation between improvements in motor function of FMA and the length of stay in PAC was noted in our study.

Limitation
There are some limitations in our study. This is a retrospective and a single center research, so the results may not virtually apply to nation-wide or even worldwide stoke patients. Subgroup analysis, such as stroke type, gender and age, should be further investigated to acquire more information. Different recorders in each PAC may derive bias and so does the training efficacy variant in each institution. Last but not least, the judging scale may not fully represent the patients' recovery and each measurement had its own restriction (i.e., 6MWT couldn't represent cardiopulmonary capacity in bed-ridden stroke patients). Therefore, more survey is needed to clarify the above questions.

Conclusions And Implications
Longer duration of hospitalization in PAC is conducive to enhancing ADL function,

Availability of data and material
The datasets used and analysed during the current study are available from the corresponding author on reasonable request.

Competing interests
The authors declare that they have no competing interests.

Funding
There's no funding regarding this study.   STROBEChecklistPageBrackets.pdf