Abstract
This study intended to identify the risk factors for injurious falls that led to hospitalization of older persons living in the community. A hospital-based unmatched incident case-control study was done among 251 cases and 250 controls admitted at a tertiary care centre in Kerala. Mean age of cases was 71.6 ± 9.13 years and that of controls was 67.02 ± 6.17 years. Hip fractures were the predominant injury following falls. Falls were mostly a result of intrinsic causes. After adjusting for other variabes, the risk factors for all injuries were age above 70 years (odds ratio [OR] = 2.25; 95% confidence interval [CI] = 1.46–3.46), previous fall history (OR = 2.76; 95% CI = 1.08–7.08) , impaired vision (OR = 4.49; 95% CI = 2.77–7.30), not living with spouse (OR = 1.97; 95% CI = 1.31–2.97), door thresholds (OR = 1.52; 95% CI = 1.01–2.29), and slippery floor (OR = 2.37; 95% CI = 1.31–4.32). The risk factors for hip fractures and other injuries were identified separately. Fall prevention strategies among older persons are warranted in Kerala.
Keywords: elderly, geriatric health, gerontology, older adults, geriatrics, injury prevention, injury, accident, aging, Trivandrum
Introduction
Falls are a major public health problem among older persons because they are one of the leading causes of injury and death.1–3 As a cause of death, injury ranks fifth among older persons, with the majority of these deaths being the result of falls.4, 5 Every year, 25% to 30 % of older persons sustain falls in developed countries.6–9 Fall-related injuries may result in premature deaths, long-term confinement to bed, disability, and dependence in older persons.1–3
The proportion of older persons is growing globally.9 Two-thirds of older persons in the world are in developing countries that are not yet ready to recognize falls as a public health problem.10, 11 There is a lack of information regarding the risk factors for falls and related injuries in India. Kerala state has a proportion of 12.6% of older persons,12 the highest among all states in India. There are limited studies on falls among older persons in the country.13–15 This study is an attempt to identify the risk factors for fall-related injuries that led to hospitalization among older persons in Thiruvananthapuram, Kerala.
Methodology
A case-control study was done at Government Medical College Hospital, Thiruvananthapuram (MCH), a tertiary care and training hospital in the capital city of Kerala, India. The sample size was estimated using Epi info stat calc. With 95% confidence that a difference detected is real, 80% power to detect a difference if there is one in the underlying population, and an expected frequency of exposure among the non-ill group of 28%,16 241 cases and 241 controls in a 1:1 ratio were needed to get an odds ratio (OR) of 1.75 or greater. During the study period (January to July 2013), 251 cases and 250 controls were recruited.
Participants were persons aged 60 years and above. Consecutive admissions to the Surgery, Orthopaedics and Neurosurgery wards of MCH during the study period were included. Those admitted with injuries following falls were termed cases, and those admitted with other illness were recruited as controls without matching. Those who were severely ill, admitted for road traffic injuries, living in old age homes, who fell one month prior to the date of interview, and who were unable to consent were excluded from the cases. Those who were admitted to a hospital for fall-related injuries in the past 6 months were excluded as controls. Ethical clearance was obtained from Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India (SCT/IEC-434/September 2011 dated October 3, 2012).
The researcher and 2 trained investigators collected information using a structured pretested interview schedule prepared for this study. Injurious falls were defined as falls that resulted in injuries that required hospitalization for at least 24 hours. Information on sociodemographic characteristics, history of falls in the past 12 months, circumstances of falls, morbidity profile, drug history, and environmental characteristics were elicited from cases as well as controls. In addition, cases were asked about their recent falls and related injuries for which they were admitted. Data were analyzed using SPSS version 20.17 Frequencies and proportions were calculated for categorical variables and means with standard deviations for continuous variables. χ2 Tests were done to analyze categorical data. Stratification was done at different levels to adjust for nonmatching, confounding, and bias. Regression analysis was done to identify risk factors for all injuries by adjusting for confounders. Multinomial regression was done to identify the risk factors for hip fractures and other injuries separately.
Results
The age of the cases ranged from 60 to 95 years (mean age = 71.6 ± 9.1 years), and that of the controls from 60 to 89 years (mean age = 67.02 ± 6.2 years). The mean monthly income of the households of cases was 4092 ± 4.6 INR (300-50 000 INR) compared with 3023.40 ± 3.2 INR (300-20 000 INR) in controls. A comparison of cases and controls is given in Table 1.
Table 1.
Comparison of Cases and Controls.
| Characteristics | Cases, n = 251 (%) |
Controls, n = 250 (%) |
Unadjusted OR (95% CI) |
|
|---|---|---|---|---|
| Sex | Females | 165 (65.7) | 121 (48.4) | 2.05 (1.43–2.93) |
| Males | 86 (34.3) | 129 (51.6) | Reference | |
| Age in years | ≥70 | 144 (57.4) | 74 (29.6) | 3.20 (2.21–4.63) |
| <70 | 107 (42.6) | 176 (70.4) | Reference | |
| Monthly income in INR |
≥5000 | 50 (19.9) | 28 (11.2) | 1.97 (1.20–3.25) |
| <5000 | 201 (80.1) | 222 (88.8) | Reference | |
| Marital status | Single | 138 (55.0) | 81 (32.4) | 2.55 (1.77–3.66) |
| Married | 113 (45.0) | 169 (67.6) | Reference | |
| Formal education | No | 68 (27.1) | 41 (16.4) | 1.89 (1.23–2.93) |
| Yes | 183 (72.9) | 209 (83.6) | Reference | |
| Staying in own house | No | 92 (36.7) | 58 (23.2) | 1.92 (1.30–2.83) |
| Yes | 159 (63.3) | 192 (76.8) | Reference | |
| Type of ration card | APLa | 95 (37.8) | 89 (35.6) | 1.10 (0.77–1.58) |
| BPLb | 156 (62.2) | 161 (64.4) | Reference | |
| No. of children | >3 | 111 (44.2) | 81 (32.4) | 1.64 (1.14–2.37) |
| ≤3 | 140 (55.8) | 169 (67.6) | Reference | |
| No. of family members |
>5 | 63 (25.1) | 61 (24.4) | 1.04 (0.69–1.56) |
| ≤5 | 188 (74.9) | 189 (75.6) | Reference | |
| Physical activity(in min/wk) |
≥150 | 174 (69.3) | 149 (59.6) | 1.53 (1.06–2.21) |
| <150 | 77 (30.7) | 101 (40.4) | Reference | |
| Frequency of meals/d |
<2 | 13 (5.2) | 4 (1.6) | 3.36 (1.08–10.45) |
| ≥2 | 237 (94.8) | 246 (98.4) | Reference | |
| Vision impairment | Yes | 107 (41.8) | 29 (11.6) | 5.48 (3.46–8.69) |
| No | 144 (58.2) | 221 (88.4) | Reference | |
| Respiratory diseases | Yes | 31 (12.4) | 15 (6.0) | 2.21 (1.16–4.20) |
| No | 220 (87.6) | 235 (94.0) | Reference | |
| History of falls in past 12 months |
Yes | 25 (10.0) | 7 (2.8) | 3.84 (1.63–9.05) |
| No | 226 (90.0) | 243 (97.2) | Reference | |
| Multimorbidity, ≥2 illnesses |
Yes | 129 (51.4) | 101 (40.4) | 1.56 (1.10–2.22) |
| No | 122 (48.6) | 149 (59.6) | Reference | |
| On antacids | Yes | 17 (6.8) | 4 (1.6) | 4.47 (1.48–13.47) |
| No | 234 (93.2) | 246 (98.4) | Reference | |
| Type of floor | Slipperyc | 42 (16.7) | 26 (10.4) | 1.73 (1.03–2.92) |
| Nonslipperyd | 209 (83.3) | 224 (89.6) | Reference | |
| Furniture as tripping hazard |
Yes | 19 (7.6) | 8 (3.2) | 2.48 (1.06–5.77) |
| No | 232 (92.4) | 242 (96.8) | Reference | |
| Using walk aid | Yes | 40 (15.9) | 19 (7.6) | 2.31 (1.29–4.11) |
| No | 211 (84.1) | 221 (92.4) | Reference | |
| Way to the entry of the house |
Coarse | 68 (27.1) | 45 (18.0) | 1.69 (1.11–2.59) |
| Smooth | 183 (72.9) | 205 (82.0) | Reference | |
| Tripping hazards around the house |
Present | 58 (23.1) | 30 (12) | 2.20 (1.36–3.57) |
| Absent | 193 (76.9) | 220 (88) | Reference | |
| Slippery surfaces around |
Present | 50 (19.9) | 33 (13.2) | 1.64 (1.01–2.64) |
| Absent | 201 (80.1) | 217 (86.8) | Reference |
Abbreviations: OR:odds ratio; CI: confidence interval.
Above poverty line.
Below poverty line.
Marble/mosaic/tiled floor.
Cement/cow dung–smeared/mud floor.
The majority of those who suffered a fall (men, 93 %; women, 95 %) were admitted with hip fractures, followed by head injuries (men, 6 %; women, 3 %). Injuries of the spine and fractures of other bones constituted the rest in both sexes. The majority of the cases (74%) fell on the same level (men, 66%; women, 78%) and 15% from a height (men, 27%; women, 9%). The rest were during a transfer from the existing position such as trying to get up from a chair or cot. Out of the falls from a different level, 87% among men were from a considerable height, but among women, 60 % of such falls were on steps.
Falls were a result of intrinsic causes (fainting, syncopial attacks, and giddiness; 27%), extrinsic causes (slipping and tripping; 66%), and a combination of both (7%). Among the older group (≥70 years old), 67% of the injurious falls were a result of intrinsic causes. The majority of injurious falls (66% (men, 70%; women, 64%)) happened during the daytime (6 am to 6 pm).
Steps or stairs were directly involved in 10% of injurious falls. Slipping was frequently a result of the slippery nature of the floors, accentuated by the presence of water, slippery cloth, or polythene bags on the floors and greasy ointment smeared on the foot.
More than half of the respondents took regular medication for chronic diseases (cases, 55%; controls, 49%). Among the cases, women took medicines more frequently (women, 64%; men, 36%). It was found that 42% of cases missed medicines on the day of the fall. New medicines had been introduced for 39% of the cases, and dosage had been altered for 20% recently.
Among those who had a fall, 10% (women, 12.7%; men, 4.7%) had a history of falls in the past 12 months, and 28% (women, 33.3%; men, 17.4%) had a history of falls in the past 5 years. Out of the 21 women who fell in the past one year, 7 persons sustained fractures. The results of regression analyses are illustrated in Table 2.
Table 2.
Risk Factors for All Injuries, Hip Fractures, and Other Injuries.
| Case (%) | Control (%) | Crude OR (95% CI) |
Adjusted OR (95% CI) |
|||
|---|---|---|---|---|---|---|
| All injuriesa | Age in years | ≥70 | 144 (57.4) | 74 (29.6) | 3.20 (2.21–4.63) | 2.25 (1.46–3.46) |
| <70 | 107 (42.6) | 176 (70.4) | Reference | Reference | ||
| History of falls | Yes | 25 (10.0) | 7 (2.8) | 3.84 (1.63–9.05) | 2.76 (1.08–7.08) | |
| No | 226 (90.0) | 243 (97.2) | Reference | Reference | ||
| Vision impairment |
Yes | 107 (41.8) | 29 (11.6) | 5.48 (3.46–8.69) | 4.49 (2.77–7.30) | |
| No | 144 (58.2) | 221 (88.4) | Reference | Reference | ||
| Marital status | Single | 138 (55.0) | 81 (32.4) | 2.55 (1.77–3.66) | 1.97 (1.31–2.97) | |
| Married | 113 (45.0) | 169 (67.6) | Reference | Reference | ||
| Slippery floor | Yes | 42 (16.7) | 26 (10.4) | 1.64 (1.01–2.64) | 2.37 (1.31–4.32) | |
| No | 209 (83.3) | 224 (89.6) | Reference | Reference | ||
| Door threshold |
Present | 141 (56.2) | 110 (44) | 1.63(1.15–2.32) | 1.52 (1.01–2.29) | |
| Absent | 110 (43.8) | 140 (56) | Reference | Reference | ||
| Hip fracturesb | Marital status | Single | 104 (61.2) | 81 (32.4) | 3.29 (2.19–4.93) | 2.43 (1.34–4.43) |
| Married | 66 (38.8) | 169 (67.6) | Reference | Reference | ||
| Formal education |
No | 53 (31.2) | 41 (16.4) | 2.31 (1.45–3.68) | 1.92 (1.08–3.41) | |
| Yes | 117 (68.8) | 209 (83.6) | Reference | Reference | ||
| Age in years | ≥ 70 | 60 (35.3) | 74 (29.6) | 4.36 (2.88–6.61) | 2.56 (1.55–4.23) | |
| < 70 | 110 (64.7) | 176 (70.4) | Reference | Reference | ||
| History of falls | Yes | 23 (13.5) | 7 (2.8) | 5.43 (2.27–12.97) | 4.01 (1.44–11.22) | |
| No | 147 (86.5) | 243 (97.2) | Reference | Reference | ||
| Vision impairment |
Yes | 73 (46.5) | 29 (11.6) | 6.62 (4.10–10.80) | 5.39 (3.10–9.34) | |
| No | 91 (53.5) | 221 (88.4) | Reference | Reference | ||
| Respiratory ailments |
Yes | 25 (14.7) | 15 (6.0) | 2.70 (1.38–5.29) | 2.37 (1.08–5.24) | |
| No | 145 (85.3) | 235 (94.0) | Reference | Reference | ||
| Using walk aid | Yes | 36 (21.2) | 19 (7.6) | 3.27 (1.80–5.92) | 2.29 (1.13–4.62) | |
| No | 134 (78.8) | 231 (92.4) | Reference | Reference | ||
| Slippery floor | Yes | 31 (18.2) | 26 (10.4) | 1.92 (1.10–3.37) | 2.91 (1.41–6.00) | |
| No | 139 (81.8) | 224 (89.6) | Reference | Reference | ||
| Other injuriesb | Vision impairment |
Yes | 26 (32.1) | 29 (11.6) | 3.60 (1.97–6.61) | 3.36 (1.79–6.31) |
| No | 55 (67.9) | 221 (88.4) | Reference | Reference |
Abbreviations: OR, odds ratio; CI, confidence interval.
The factors entered but dropped were female sex, no formal education, monthly income <Rs 5000, respiratory ailments, and using walk aid.
The factors entered but dropped were female sex and monthly income <Rs 5000.
Discussion
This study identified several modifiable risk factors, including built environment factors for fall-related injuries among older persons in Thiruvananthapuram. The findings provide information regarding falls and related injuries among older persons in India and Kerala.
The most frequent cause of hospitalization was hip fractures, and they were more among women, similar to the findings of Tinetti et al8 (OR = 1.2; 95% CI = 0.9–1.6). Hip fractures resulted from trivial falls in women but falls from height in men. The mechanical energy during a fall is absorbed differently on different parts of the body in men (head) and women (hip).18
Extrinsic factors triggered the majority of injurious falls similar to what was found by Dsouza et al14 (73.7%). Slipping and tripping——as the cause of fall and reasons for slipping inside and outside the house were analogous with earlier reports.6, 14, 19 As one ages, the “shift” strategy (shifting the weight to prevent a fall while one slips) will gradually change to “step” strategy (rapid steps), which is less efficient in preventing falls.4 The reduction in clearance of the recovery foot during the swing phase of the gait elevates tripping risk in an older person.20
Most of the older persons fell during the daytime when they were alone, as reported by Berg et al (63%).21 Similar to earlier reports, more women fell and got injured within and around the house compared with men, who fell away from home at workplaces and on the roads.22, 23
Several functions decline, and body organs become more susceptible to injuries with age.20 Similar to an earlier study, the higher proportion of intrinsic falls among the older group (70 years and above) can be attributed to intrinsic factors.22 Extrinsic factors caused more falls among the younger group (60–69 years old), emphasizing the importance of modification of the environment in the prevention of injurious falls.
A history of fall in the previous year was identified as a risk factor, analogous to earlier reports.24, 25 An older person with a history of falls has an inflexible, clumsy gait and lack of control over posture and body position.18, 20 In people with reduced visual acuity, depth perception is deranged, which is very important in maintaining stability of the posture and in negotiating obstacles.8, 24, 26 It increased the chances of hip fracture.
Living with spouse had a protective effect against fall-related injuries, including hip fractures. The “spouse surveillance,” which works in the case of head and neck cancers, might work in falls as well.27 Presence of the spouse facilitates early detection and treatment of any illness. It increases chances of physician visits and regularity of treatment, leading to better control of chronic illness, which in turn reduces fall risk.27 A spouse can identify problems related to balance and gait at the earliest and assist and guard against falls and injuries. Perhaps living with spouse is an indicator of social support, which is crucial in the prognosis for and recovery from several illnesses.
Limited studies have identified slippery floors as a risk factor for falls and injuries. Slippery surfaces (cemented surfaces with moss growing during the rainy season) outside the house or on the road and smooth flooring (glossy tiles, polished marble, or granite) were risk factors for falls, similar to what was found in the study by Dsouza et al.14
Door sills (a part of traditional architecture in many cultures in Asia) were identified as a risk factor for injurious falls, similar to what was found in a Korean study among women.28 The foot on striking a doorsill, trips and abruptly halts the body’s center of gravity, which was in motion.28 This shift of the center of gravity away from the area of the body’s support base leads to a fall.
Older persons lacking formal education showed a higher risk for hip fractures in our study. Li et al found that education level lower than primary school was significantly associated with falls.29 Lack of resources to gain information and not being aware of preventive measures increased the risk of falls among older persons. People with lower education levels might find it difficult to understand and follow instructions to prevent any illness.
Older persons with chronic lung diseases were found to be prone to hip fractures. Perhaps dysfunction of the skeletal muscle and cerebral hypoxia in chronic obstructive lung diseases were the reasons for increased falls among those with lung disease.2, 30
Walk aids were a significant risk factor for hip fractures, similar to reports by Dsouza et al.14 Either the physical or functional status of the individual who uses a walk aid or an improper walk aid itself can be the cause of falls.
Selection of hospital controls limited analysis of comorbidities with injurious falls. Also, we could not record functional aspects such as muscle strength and coordination. Excluding seriously ill or dead persons in view of ethical constraints might also have resulted in some distortions. Further research into the contextual aspects of this important problem of aging in this part of the world is warranted.
Acknowledgments
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was partially supported by the Fogarty International Centre, National Institutes of Health, awarded to the first author (D43TW008332; Asian Collaboration for Excellence in Non-communicable Diseases [ASCEND] research network). The contents of this publication are solely the responsibility of the authors and do not necessarily represent the official views of the National Institutes of Health and ASCEND Research Network.
Footnotes
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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