Risk factors for ground-level fall injuries during active activity in older patients

1. Introduction

The World Health Organization (WHO) defines a fall as an incident that causes a person to unintentionally come to rest on the ground, floor or other lower level [1]. Most of the injured patients are admitted to emergency departments (ED), and 10–15% of trauma patients of all ages admitted to ED had fall injuries [2]. Ground-level falls are the most common cause of injury, especially in older patients [1, 3, 4, 5], because they are more vulnerable to trauma than younger people [6, 7, 8]. Currently, the proportion of older patients in the total population is increasing rapidly worldwide [1, 2], and falls in older patients are becoming a growing public health concern [9, 10]. Older patients are more likely to experience severe injuries. Despite being at low risk due to comorbidities, the mortality risk is increased [11], and it can be a major socioeconomic problem [6]. Therefore, studies analyzing the characteristics of fall injuries in older patients and the development of preventive strategies can reduce medical costs. In a previous study, both intrinsic (neurosensory input) and extrinsic (environmental) factors were found to play a role in the fall process, either individually or in combination [12]. The major intrinsic factors were gait characteristics [12], sex [4, 13], alcohol consumption [3], and the use of psychotropic (benzodiazepines and antidepressants) and cardiovascular drugs (beta-blockers and antiarrhythmics) [14]. The major extrinsic factors were slopes [12, 15], the type of surface [1, 3, 9, 16, 17, 18, 19], light intensity [20], type of footwear [16, 20], and location of the fall injury [9, 16, 17].

In addition to the other factors, researchers have focused on the difference between indoor and outdoor environments [17, 21]. More falls occur outdoors than indoors because more leisure time physical activity carried a higher risk for outdoor activity [17]. Outdoor falls were more common in healthy older people, whereas indoor falls were more common in inactive older people [21], indicating an association between poor health and indoor falls [17]. Thus, considering a patient’s baseline health status, we can assume that ground falls during inactivity would be more severe. However, patients move faster and more passionately during activity, which can be a risk factor for ground fall severity. Therefore, we investigated the patients’ characteristics of fall injury during active activity and inactive activity, and the severity in both groups. The results can be helpful in establishing preventive strategies for fall injuries in geriatric patients, which can reduce the medical costs.

2. Materials and methods

2.1 Study design and setting

Emergency Department-based Injury In-depth Surveillance (EDIIS) data from the Korea Disease Control and Prevention Agency (KDCA) were used in this retrospective case-control study. EDIIS data are currently being collected from 23 hospitals, starting with 6 hospitals in 2006, and the collecting variables were revised in 2011. Common data from 23 hospital Emergency Departments (EDs) and in-depth injury related data in four categories from 4~8 hospital EDs have been collected. In-depth data were classified into traffic accidents; head and neck injury; injury in preschool aged children; and suicide, poisoning, fall from a height and ground fall injury in older people. Since the in-depth data for ground fall injury in older people, which included environments of floor, were collected in only six hospitals, and the study group included patients aged 65 years or older who visited the ED of six university hospitals from January 2011 to December 2020 for ground-level fall injuries (Fig. 1).

Fig. 1.Flow chart of the study population. ED: Emergency Department.

3. Results

A total of 33,924 patients were enrolled. There were 4887 (14.4%) active patients and 29,037 (85.6%) inactive patients (Fig. 1).

Active patients were more commonly injured in spring than inactive patients (25.3% vs. 22.3%). In contrast, inactive patients were more commonly injured in summer (23.8% vs. 22.2%) and autumn (27.2% vs. 26.2%). Active patients were more commonly injured from 12:00–17:59 (38.4% vs. 36.7%) and 18:00–23:59 (34.8% vs. 27.4%), whereas inactive patients were more commonly injured from 06:00–11:59 (28.2% vs. 20.3%). The proportion of males in the active patient group (53.6%) was higher than that of females, which was distinct from inactive patients (34.2%). Regarding the age of the subjects, the proportion of patients in the 65–74 years’ age range was higher in the active group (62.4%), whereas the proportion of relatively older patients (75–84 years, and older than 85 years) was higher in the inactive group (44.0% and 18.9%). The most common location of injury occurrence in the active group was a transportation area (50.6%) and home or residential facilities in the inactive group (62.8%). The proportion of patients who had consumed alcohol was higher in the active group (26.8%) than in the inactive group (5.7%). The floor characteristics of falls in each group were also investigated. In the active group, the proportions of sloping floors (12.4%) and the presence of obstacles (10.5%) were higher, and the proportion of concrete floor (84.3%) was lower than that in the inactive group (Table 1).

More patients with head and neck injuries (48.3%) were found in the active group, whereas more patients with thoracic (5.4%) and abdominal (8.5%) injuries were found in the inactive group. In the inactive group, fewer patients were discharged (60.4%), more patients were admitted to general wards (32.4%), and the proportion of those undergoing surgery was higher than that in the active group (20.9%), whereas injury severity did not differ between the groups (Table 2).

The main factors significantly associated with ground fall injuries in elderly patients during activity were male sex, ages between 65–74 years and 75–84 years compared to greater than 85 years, injury time other than 00:00–05:59, alcohol consumption, sloping floor and floor type other than concrete (Table 3, Fig. 2).

Fig. 2.Multivariate analysis for individual and environmental factors related to ground fall injuries in older people during active activity. *Odds ratio ≥5.00.

There were more inactive patients in this study; thus, propensity score matching analysis (1:1) was performed to adjust for different distributions of baseline characteristics (sex, alcohol consumption and age) (Supplementary Table 1).

After propensity score matching, active patients were more commonly injured from 12:00–17:59 (38.4%), whereas inactive patients were more commonly injured from 00:00–05:59 (9.2%) and 18:00–23:59 (38.7%). There was no difference in the proportion of injuries according to the season in the groups. The most frequent location of injury occurrence was transportation areas in the active group (50.6%) and home or residential facilities in the inactive group (45.5%). Regarding floor characteristics, the proportions of injuries on slippery floors (9.4%) and sloping floors (12.4%) were higher in the active group, and the proportions of injuries occurring in the presence of obstacles (22.2%) and concrete floors (97.1%) were higher in the inactive group. More patients with head and neck injuries were found in the inactive group (69.4%), and more patients with injury at other locations were found in the active group. More patients in the active group were transported to an ED from another medical facility (11.6%), and more patients in the inactive group were transported to an ED by a public ambulance (43.7%) or individual transportation (47.0%). Injury severity in the active group was higher than that in the inactive group (6.1% vs. 5.1%) (Table 4).

The main factors significantly associated with ground fall injuries in elderly patients during activities after 1:1 propensity score matching were injury time other than 00:00–05:59 h, slippery floors, sloping floors, the absence of obstacles, and floor type other than concrete (Table 5, Fig. 2).

4. Discussion

This study compared the characteristics of ground fall injuries in older patients during activity with those experienced during inactivity. The time of injury other than midnight (00:00–05:59), relatively younger age, alcohol consumption, sloping floor and floor type other than concrete were associated with ground-level fall injuries in older patients during activity. After 1:1 propensity score matching analysis for three baseline characteristics (age, sex and alcohol ingestion), the injury in older patients due to ground-level falls during activity was significantly associated with an occurrence at 06:00–17:59 compared to 00:00–05:59, slippery floors, slope, the absence of obstacles and floor type other than concrete.

In this study, ground falls during activity occurred more frequently from 06:00–23:59, compared to during inactivity. Ordinarily, people are awake from morning to evening [16]; thus, activities are conducted more frequently during daytime hours than during nighttime hours. Among the elderly, the relatively younger patients were more frequently injured during active activity than the older patients. Older patients spend more time indoors [16, 17], and more leisure time was associated with outdoor fall injuries [17]. Indoor falls were common in inactive older people, in contrast to outdoor falls, which were more common in healthy older people [21]. According to a previous argument, relatively younger people are healthier than older people and more likely to experience outdoor falls, which are related to activities.

Older patients are also more likely to have severe injuries because of the presence of comorbidities [11]. However, in this study, injury severity in the active group was not lower than that in the inactive group. Furthermore, after propensity score matching analysis, injury severity in the active group was higher than that in the inactive group. Activities, such as leisure-time physical activity, carry a higher risk of falls [17]; thus, caution during activity is necessary, despite the healthier condition of relatively younger patients.

A previous study reported that more men were injured due to ground-level fall injuries during activities than women, probably because of differences in daily routines between the two sexes [16]. Alcohol consumption was significantly associated with ground fall injuries during active activities. Another study reported that, in addition to environmental factors, neurosensory input plays a role in the fall process [12], and declines in motor, sensory and cognitive functions increased the risk of falling while walking on different surface conditions [9]. Activities could be conducted on different surfaces compared to where inactivity occurs; thus, motor-sensory dysfunction related to alcohol consumption more strongly influences falling when they are active.

After performing 1:1 propensity score matching for age, sex and alcohol consumption, the time of injury and environmental factors were associated with ground fall injuries during activity. Daytime, which is from 06:00–17:59, was associated with ground fall injuries during activities compared to midnight because ordinary people are more active in the daytime. More ground fall injuries while being active occurred on slippery floors and floor type other than concrete. These floor types included soil, ballast and multi-surface terrains, which are more slippery than concrete or asphalt. The slip potential was associated with ground-reaction forces [15]; thus, slippery floors are a risk factor for fall injuries [1, 16]. During an activity, people move and work more actively, and fast movements can increase the slip potential more strongly than inactivity. A sloped floor was also a significant risk factor for falls when they were active. A slope increases the slip potential by reducing the ground reaction force, which decreases body balance and can cause fall injuries [12, 15]. As an example, ground-level fall injuries on a sloped roof are an important safety concern for construction workers [15].

In contrast to previous studies, this study found that the presence of obstacles inversely affected ground-level fall injuries during activities. In the swinging phase during walk, stumbling was triggered by obstacles, and patients experienced ground-level falls [16]. For example, door sills were a risk factor for injurious falls [18]. In addition, visual acuity and depth perception decline in older people, and this skill is very important in negotiating obstacles [18]. As per our assumption, relatively safety environment, such as absence of obstacles, can trigger safety frigidity, which can reduce concentration during active activities. Further studies should be conducted to assess the association between the obstacles and ground fall injuries during activities.

There were some limitations to this study. First, this study was conducted in 6 university hospitals; thus, generalizability at various levels of the hospital could be weak. Categorization of ground fall patients was based on the activity during injury, but there could be some inconsistency between the natural activity level and activity during injury because of limitations of this retrospective case-control study. Medication history was not investigated. Several previous studies have identified medications as a risk factor in fall injuries [4, 14, 22], especially the fact that antiarrhythmics, non-selective beta-blockers, benzodiazepines, psychotropics and antidepressants increased the fall risk in elderly people [14]. Studies have also shown that cognitive impairment increased the fall risk in elderly people [23]. Different shoes can also affect the balance differently, and improperly worn shoes can be a risk factor for fall injuries [12, 16]. Low levels of education were also associated with falls due to problems in understanding the preventive measures [16, 18]. Medication history and information on shoes were not included in this study, and the level of education was not analyzed because many values were missing. Finally, muscle strength can be a significant risk factor for falls [4]. In future, further studies should include a detailed medication history. Furthermore, the patient’s natural activity level should be evaluated. In addition to characteristics of the floor, the type of shoes should be evaluated, as it has an effect on ground-level fall injury.

5. Conclusions

In the case of ground-level fall injuries in older patients, the factors associated with trauma during activity were daytime injury, slippery floor, slope, the absence of obstacles, and floor type other than concrete. Injury severity in the active group was not lower than that in the inactive group, despite the relatively younger age. Based on our study, preventive strategies should be established for reducing ground-level fall injuries in older patients during activity, especially in sloping areas and slippery floors. Preventive strategies should include wearing compatible footwear, caution regarding sloping areas, and maintenance of unpaved roads. Fall prevention toolkits for patients who are vulnerable to ground-level fall injuries can be helpful to increase the awareness of injury. For patients who take a variety of medications, a recommendation for deprescription of unnecessary medications can also be helpful.

Availability of data and materials

The Korea Disease Control and prevention Agency (KDCA) has the authority to access and use these data. Data of this study can be requested through the Department of Injury Prevention of the KDCA by E-mail (kcdcinjury@korea.kr) or website (http://www.kdca.go.kr).

Author contributions

JSH, SHK and SPK—designed the research study. JSH, SHK, SCL, SPK, GCC, MJK, DHL and YRK—performed the research. JSH and SHK—provided help and advice on this study; analyzed the data; wrote the manuscript. All authors contributed to editorial changes in the manuscript. All authors read and approved the final manuscript.

Ethics approval and consent to participate

This study was reviewed and approved by Ulsan University Hospital Institutional Review Board (UUH-IRB-2022-06-039). Data used in this study were anonymized before using them. All methods in this study were performed in accordance with the guidelines of the Declaration of Helsinki. The requirement for obtaining informed consent was waived by the Institutional Review Board due to the retrospective nature of this study.

Acknowledgment

Researchers would like to thank the Korea Center for Disease Control Prevention Agency (KCDA) for allowing access to the KCDA funded registry data. This work was supported by the Big Data Center of Ulsan University Hospital for statistical analyses.

Funding

This research received no external funding.

Conflict of interest

The authors declare no conflict of interest.

Supplementary material

Supplementary material associated with this article can be found, in the online version, at https://oss.signavitae.com/mre-signavitae/article/1716736766057037824/attachment/Supplementary%20material.docx.