Elderly’s falls are among the serious and common hospital complications (13). These falls impose a considerable financial burden on hospitals each year and leave a negative effect on the limited resources of counties’ healthcare system due to the services they consume, length of stay (LOS) and costs (15,23). The results of the study showed that increasing rates of falls in the hospital, especially among the female elderly and those with chronic diseases, would increase the cost of medical services.
The World Health Organization (WHO) states that “age over 60 years” and “female gender” are two biological factors that increase the possibility of falls (8). Many studies have shown that falls are more prevalent in elderly women (4-17-20-22-30). Hartholt found that women fall 2-3 times (58%) more than men (22). It was found that 56.96% of the falls were related to women and 43 % related to men, showing 1.32% increase in the rate of falls in women. According to the WHO reports, the rate of life-threatening falls increased with age in both sexes and the highest rate was seen in individuals over 85 years. Moreover, falls leading to death were more prevalent in men while falls occurred more in women (8).
A study in 2015 showed that, about 64% of admitted elderly experienced falls, 54% of which led to death (35). In the present study, 79.74% of personal referrals in the elderly led to falls and 89.86% of the falls led to severe injury. This rate would increase as the number of elderly increases in the society.  Osteoporosis, especially in women leads to lower ability to maintain balance and increased incidence of severe fatal falls. Stevens studied the effect of underlying diseases in increasing the risk of falls (20). Studies have shown the effect of cardiovascular disease on the risk of falls in the elderly (15,36,37). The chance of falling increases with a history of myocardial infarction (18). In the current study, the highest number of falls and fall-related costs were due to cardiovascular diseases, so that the elderly with such diseases comprised 54.42% of the falls and 64% of the fall-related costs (5.505 US$). This could be attributed to the use of heart medications that cause a sudden decrease in blood pressure, blurred vision and loss of balance. Sudden change of mood (from supine to standing) could also be effective in causing falls.
Neurological diseases, such as stroke (89%), Parkinson’s disease (77%), epilepsy (57%), headache (28%), delusion (60%), multiple sclerosis, and migraine increase the rate of falls (16,38,39). Another study also showed that Parkinson’s disease, syncope, and other neurological diseases increased the possibility of falls by 62%, 57%, and 48% in the elderly, respectively. Stroke, Parkinson’s disease, chronic pain, dizziness, loss of balance, and weak eye sight increase the risk of falling (19). It was also found that elderly patients with neurological diseases comprised 24.05% of falls with a cost of 1.729 US$ (20.10%). Most of these falls were due to taking certain medicine, sudden neurological attacks, and related cognitive and environmental disorders leading to lack of balance and falling.
Some studies have shown that the elderly
with a history of infectious disease (influenza, pneumonia, etc.) have a higher chance of falling (22). In the present study, the elderly with a history of infectious disease comprised 21.53% of falls with a cost of 1.366 US$ (15.89%). Considering the wide range of infectious diseases that affect different body organs and have various complications, should be carefully monitored in patients with a history of fall. Infectious diseases present with symptoms, such as fever, diarrhea, dizziness, and the side effects of medications (dizziness, low muscle power, etc.) contribute to increase the risk of falling.
Most falls occur at night (13,40) which is in line with the present study in which 60.75% of falls occurred during 7 PM to 7 AM (P≤0.034). Visual disorders increase the chance of falls and people with these disorders are more vulnerable in the dark and when tired. Other causes of falls in these hours include consumption of several drugs and their effect on the brain and level of consciousness, being unfamiliar to the environment and existence of physical obstacles, frequent visits to the toilet during the night, the incorrect culture of not requesting help due to shame, and lack of supervision on the nurses’ behalf.
Most falls were in room and due to falling from the bed (13). A study showed that 51% of the falls result from sitting and getting out of bed leading to minor (95%) and major (5%) injuries (41). Other studies have also indicated that the bed is an important factor leading to falls (13,42-44). It was found that 60.76% of the falls were related to the bed and 68.35% occurred in patients’ rooms. Given the elderly spend most of the time in their room, prolonged rest reduces their muscle strength leading to imbalance. Falling off the bed could be due to wearing tight or loose clothing (and in our country wearing veils during rest), fear of sleeping on the bed, location of the bed, and its height. Some falls were the result of dislocation of the bedside, not being able to lower it, and attempting to get of the bed while the bedside is still up. It is necessary to add physiotherapy to the daily preventive programs of patients at risk to increase their muscle power and help them gain balance. Moreover, the correct method of using the bedside should be simple and clearly explained.
In this study, 91.13% of the patients had fallen when they were conscious or semi-conscious which was consistent with another study (13). However, two other studies did not find such results (45,46). The contradictory findings could be attributed to chance and it seems that conscious patients reported more falls or they were more aware of their injuries and described injuries better. Ten-20% of falls lead to serious injury and fracture (20) and 20-30% of falls lead to hip and head trauma (18). Moreover, hip fracture is the most prevalent trauma and comprises 70% of the costs (24). In the present study, the most prevalent injury was head injury and fractures and surgeries comprised more than 77% of medical costs. 
With respect to the costs of falls in the elderly, many studies have been done. The difference between the costs mentioned in different studies is related to the different healthcare systems, different participation plans of insurance companies, different types of injuries, and treatment plans, the advanced technologies available in some countries, different sample sizes, different data collection and analysis methods, which complicate comparison (21,26,35).  What all studies have in common is that fall-related costs impose a considerable financial burden on the hospitals and healthcare systems of all countries. This amount would further increase as the number of the elderly increases (15,21,22). The cost of falls in the elderly has been studied extensively in America. In America and England the cost of fatal and non-fatal falls adds up to 23.3 and 1.6 billion dollars, respectively, each year. The mean cost of falls is 3.476 dollars per person and it can increase to 10.749 dollars in falls leading to injury and 26.483 dollars for those requiring admission (41). In 1997, 9% of the American elderly fell yielding a cost of 6.2 million dollars (2.039 dollars per person) and this amount increased to 7.8 million dollars in 2022 (2.591 dollars per person) (17). In 2000, 10300 fatal falls and 2.6 million non-fatal falls leading to injury occurred in America (42% in hospitals and 50% at home). The cost of fatal and non-fatal falls has been estimated to be 0.2 and 19 billion dollars, respectively, 63% of which were for admission services and hospital stay (12 billion dollars), 21% for visits and consultation (4 billion dollars) and 16% for treatment services. In 2010, the cost of falls in healthcare centers of America was 11 million dollars (25). In 2012, 616.5 million dollars was spent for fatal falls and 30.3 billion dollars for non-fatal falls; which increased to 637.5 million and 31.3 billion dollars in 2015 (20,21,34). Twelve percent of American elderly reported falling in 2015 which means 80 million falls (37.2 falls for every 100 person) and 9.9 million led to injury (4.38 per 100 person) (25). In 2015, fatal and non-fatal falls cost 50 billion dollars in America (15). In the same year, treatment costs (surgery, radiography, etc.) for patients who had fallen was 4200 dollars more than costs for patients who had not fallen (11). In England, the cost of falls (treatment, admission, and litigation) comprised 87% of total treatment costs (2.3 billion pounds (5). Annually, more than 2 billion pounds are spent on fall-related injuries. Hospital falls comprise 26% of accidents (324000 cases) (14). In Finland and Australia, the mean cost of each injury due to falls is 1.049 to 3.611 dollars. The mean admission costs for each fall leading to injury in the hospital is 6.646 to 14.483 dollars (24). In 2001 and 2002, falls cost 498 million dollars. The mean financial burden on the healthcare system was 6500 dollars for each fall (47). In 2006 and 2007, 507000 falls occurred in the New South Wales leading to 143000 medical procedures and a cost of 558.5 million dollars. Eighteen percent of costs were related to admission and 84.5% related to medical services (26). In Australia, of the 27026 admitted patients, 966 experienced falls and 313 were injured. These rate increased hospitals stay for up to eight days and imposed 6669 dollars on hospitals (23). Fall-related costs have been estimated to be 43.8 billion dollars in 2020 (37).
Limitations
The most important limitation of the study is that it was a single-center study. Also, cost calculations were difficult due to price fluctuations and inflation. Due to lack of information, the effect of falls on the LOS could not be considered. Moreover, assessing primary and secondary state of consciousness could differ based on the nurse’s knowledge and experience. The effect of factors, such as physical characteristics, BMI, muscular strength, history of previous fall, severity of illness, amount of care, and insurance support could not be assessed. Lack of similar national studies for comparison was also a big challenge. 
Conclusion
The results of this study showed that even falls that do not lead to serious injury, waste medical services and leave negative effects on hospital resources and the healthcare system and increase hospital costs by 8.06%. This increase in costs could be due to changes in treatment methods and increase the LOS. It indicates the necessity of existence and implementation of fall prevention programs in hospitals, emphasizing supervision, control, and training.  This is not only necessary for reducing fall-related injuries, but also for reducing hospital costs. Intervention strategies reduce falls and as a result decrease the cost of health services.
Acknowledgments
This article was extracted from an M.A thesis approved by the Ethics Committee of the Islamic Azad University, Science and Research Branch, Tehran, Iran (IR.IAU.SRD.REC.1398). We would also like to thank all individuals who participated in and supported this study.
Author's contribution
All authors contributed to this project and article equally.All authors read and approved the fainal manuscript.
Conflict of Interest
No potential conflict of interest was reported by the authors.