Suicide is a major issue in South Korea, and falling is a common method of suicide. Further, accidental falls are a common cause of death. However, whether suicidal falls differ from accidental falls is inconclusive. This study aimed to compare suicidal and accidental falls to identify risk factors for mortality.
From March 2010 to December 2016, patients admitted to our hospital because of falls were reviewed retrospectively. Characteristics and outcomes were compared between suicide and accident groups. Injury distribution was compared using the Injury Severity Score and Abbreviated Injury Scales. Multivariate analysis was performed to identify risk factors, including suicide intent, for mortality.
Of 242 patients, 42 were included in the suicide group and 200 were included in the accident group. The suicide group showed higher fall heights and injuries of greater severity. The accident group was younger and included a higher number of men. The suicide group showed a higher mortality (23.8% vs. 6.5%, P=0.001) and a higher proportion of injuries in the lower extremities or abdomen. In the multivariate analysis, Glasgow Coma Scale score (0.575 [0.433–0.764], P<0.001), body mass index (1.638 [1.194–2.247], P=0.002), suicide intent (9.789 [1.026–93.404], P=0.047) and Injury Severity Score (1.091 [1.000–1.190], P=0.049) were identified as risk factors for mortality.
Suicidal falls were associated with poorer outcomes and a greater tendency to land feet first relative to accidental falls. Suicide intent was a risk factor for mortality.
Suicidal falls might be different from accidental falls in injury distribution, and it is still unknown whether clinical outcomes are different.
Suicidal falls have poor clinical outcome, and suicidal intent is a risk factor for mortality.
Suicide is the fifth most common cause of death and the most common cause of death in young adults in South Korea [
Several previous studies have compared accidental and suicidal falls [
This study was approved by the institutional review board at the institution with which the authors were affiliated (AJIRB-MED-MDB-19-331). Informed consent was waived by the board due to the observational nature of the study. Data regarding patients admitted to our hospital because of falls between March 2010 and December 2016 were reviewed. Patients were excluded if they were aged <18 years, had unknown suicide intent, or had died before admission. Because the minimum height of suicidal falls was 5 m in the database, patients with accidental fall heights of <5 m were excluded, although major falls are usually from heights of >6 m.
Chi-squared test was performed to analyze categorical variables, and the Mann-Whitney U test was used to analyze continuous variables, following the use of the Kolmogorov-Smirnov test for normality assumption. Injury distribution was assessed based on the Abbreviated Injury Scale (AIS) and included injuries to the head, face, neck, thorax, abdomen, spine, and upper and lower extremities, and external injuries. In addition, patients were dichotomized into survivor and non-survivor groups. Multivariate analysis was performed using logistic regression via the forced entry method; variables that were statistically significant (P<0.05) in the univariate analysis were selected as potential risk factors for mortality. Statistical analysis was performed using IBM SPSS Statistics ver. 23 (IBM Corp., Armonk, NY, USA).
Of 242 patients, 42 were included in the suicidal fall group and 200 were included in the accidental fall group (
According to ISSs, the proportion of injuries to extremities with AIS scores of ≥3 in the suicide group was higher relative to that in the accidental fall group (50.0% vs. 32.5%, P=0.031). According to AIS scores, the proportion of injuries to the lower extremities with an AIS score of ≥3 in the suicide group was higher relative to that in the accidental fall group (52.4% vs. 31.5%, P=0.010); however, no injuries to the upper extremities with an AIS score of ≥3 were recorded in the suicide group. The proportion of injuries to the abdomen with an AIS score of ≥3 in the suicide group was higher relative to that in the accidental fall group (28.6% vs. 13.0%, P=0.012) (
Fatalities were associated with higher ISSs. The non-survivor group included higher proportions of women and suicide intent and higher BMI values and fall heights relative to the survivor group (
In the univariate analysis, Glasgow Coma Scale (GCS) scores, BMI values, suicide intent, ISSs, female sex, higher fall heights, shock index scores, and initial hemoglobin levels were statistically significant; therefore, they were included in the multivariate analysis. In this analysis, GCS score (0.575; 95% confidence interval [CI], 0.433–0.764; P<0.001), BMI value (1.638; 95% CI, 1.194–2.247; P=0.002), suicide intent (9.789; 95% CI, 1.026–93.404; P=0.047), and ISS (1.091; 95% CI, 1.000–1.190; P=0.049) were identified as risk factors for mortality (
In the current study, suicidal falls were associated with poorer outcomes and higher proportions of severe injuries to the abdomen and lower extremities relative to accidental falls. Suicide intent was a statistically significant risk factor for mortality in fall patients.
In a previous study, Choi et al. [
Topp et al. [
The injury pattern differed between the suicide and accident groups in the current study. In previous studies, suicidal falls were associated with injuries to the extremities [
The study was subject to several limitations. For example, patients who died before hospital admission were excluded from the analysis, which could have skewed the reported mortality rates. Autopsy is not routinely performed in South Korea; therefore, the details of injury locations or severity were unavailable for these individuals. In addition, suicide intent cannot be measured in patients who are deceased or have severe brain damage, therefore, they were excluded from the study. Further, as the minimum fall height was established arbitrarily, it could have affected the overall results. Although fall height was not a risk factor for mortality in the current study, it is an important aspect of falls and is likely to affect outcomes. Moreover, this was a single-center study, and a nationwide dataset is required to provide more precise results.
In conclusion, suicidal falls were associated with poorer outcomes and the tendency to land feet first. GCS score, ISSs, BMI value, and suicide intent were identified as risk factors for mortality in high-level fall patients.
No potential conflict of interest relevant to this article was reported.
Distribution of injury scores of ≥3 in (A) the Abbreviated Injury Scale (divided by nine lesions) or (B) Injury Severity Score (divided by six lesions).
Demographic and clinical characteristics of patients in the suicidal and accidental fall groups
Suicide (n = 42) | Accident (n=200) | P-value | |
---|---|---|---|
Age (yr) | 33 (26–40) | 46 (38–54) | < 0.001 |
Sex, male | 18 (42.9) | 174 (87.0) | < 0.001 |
Fall height (m) | 9.5 (6.0–15.0) | 6.0 (6.0–10.0) | < 0.001 |
Body mass index | 22.1 (20.3–26.1) | 22.7 (20.5–24.9) | 0.995 |
Systolic blood pressure (mmHg) | 100 (91–126) | 122 (109–140) | < 0.001 |
Heart rate (beat/min) | 92 (82–111) | 86 (78–98) | 0.019 |
Shock index | 0.91 (0.69–1.18) | 0.70 (0.59–0.87) | < 0.001 |
Lactate (mmol/L) |
4.29 (2.42–5.10) | 2.78 (1.87–3.90) | 0.004 |
Glasgow Coma Scale | 15 (8–15) | 15 (14–15) | 0.015 |
Injury Severity Score | 22 (14–29) | 17 (13–27) | 0.035 |
AIS head | 3 (2–3) | 3 (2–3) | 0.333 |
AIS face | 2 (1–2) | 2 (2–2) | 0.429 |
AIS thorax | 3 (3–3) | 3 (3–3) | 0.748 |
AIS abdomen | 2 (2–3) | 2 (2–3) | 0.273 |
AIS extremities | 3 (2–3) | 2 (2–3) | 0.028 |
AIS external | 1 (1–1) | 1 (1–1) | 0.900 |
Values are presented as median (interquartile range) or number (%).
AIS, Abbreviated Injury Scale.
Thirty-six (five in suicide/31 in accident) patients had no initial lactate level.
Clinical outcomes of patients within the suicidal and accidental fall groups
Suicide (n = 42) | Accident (n = 200) | P-value | |
---|---|---|---|
Mortality | 10 (23.8) | 13 (6.5) | 0.001 |
Cause of death | 0.043 | ||
Central nervous system | 2 (20.0) | 8 (61.5) | |
Bleeding | 3 (30.0) | 0 (0.0) | |
Multi-organ failure | 5 (50.0) | 5 (38.5) | |
ICU LOS (day) | 3 (0–8) | 2 (0–7) | 0.239 |
Hospital LOS (day) | 26 (13–47) | 26 (17–48) | 0.653 |
24 hr pRBC (U) | 5 (0–13) | 0 (0–3) | < 0.001 |
24 hr FFP (U) | 0 (0–9) | 0 (0–2) | < 0.004 |
24 hr PLT (U) | 0 (0–16) | 0 (0–0) | < 0.007 |
Values are presented as number (%) or median (interquartile range).
ICU, intensive care unit; LOS, length of stay; pRBC, packed red blood cell; FFP, fresh frozen plasma; PLT, platelet.
Demographic, clinical, and fall-related characteristics of the survivor and non-survivor groups
Survivor (n=219) | Non-survivor (n=23) | P-value | |
---|---|---|---|
Age (yr) | 45 (34–53) | 40 (34–56) | 0.934 |
Sex, male | 178 (81.3) | 14 (60.9) | 0.030 |
Fall height (m) | 6 (6–10) | 10 (7–15) | 0.002 |
Intent (suicide) | 32 (14.6) | 10 (43.5) | 0.002 |
Body mass index | 22.6 (20.3–24.8) | 25.8 (22.5–28.1) | 0.001 |
Systolic blood pressure (mmHg) | 120 (105–140) | 98 (82–122) | 0.002 |
Heart rate (beat/min) | 86 (78–98) | 111 (95–125) | < 0.001 |
Shock index | 0.71 (0.59–0.87) | 1.06 (0.92–1.51) | < 0.001 |
Initial lactate (mmol/L) |
2.78 (1.89–3.80) | 7.26 (4.39–9.00) | < 0.001 |
Initial hemoglobin (g/dl) | 12.9 (11.5–14.2) | 11.2 (9.3–12.6) | 0.005 |
Glasgow Coma Scale | 15 (15–15) | 5 (3–8) | < 0.001 |
Injury Severity Score | 17 (13–25) | 34 (29–41) | < 0.001 |
AIS head ≥ 3 | 47 (21.5) | 16 (69.6) | < 0.001 |
AIS face ≥ 3 | 5 (2.3) | 2 (8.7) | 0.135 |
AIS thorax ≥ 3 | 109 (49.8) | 18 (78.3) | 0.009 |
AIS abdomen ≥ 3 | 47 (21.5) | 12 (52.2) | 0.001 |
AIS extremity ≥ 3 | 80 (36.5) | 6 (26.1) | 0.320 |
Values are presented as median (interquartile range) or number (%).
AIS, Abbreviated Injury Scale.
Thirty six (35 in survivor/one in non-survivor) patients had no initial lactate level.
Risk factors for mortality
Univariate analysis |
Multivariate analysis |
|||
---|---|---|---|---|
Odds ratio (95% CI) | P-value | Odds ratio (95% CI) | P-value | |
Glasgow Coma Scale | 0.624 (0.536–0.726) | < 0.001 | 0.575 (0.433–0.764) | < 0.001 |
Body mass index | 1.296 (1.139–1.474) | < 0.001 | 1.638 (1.194–2.247) | 0.002 |
Intent (suicide) | 4.495 (1.817–11.119) | 0.001 | 9.789 (1.026–93.404) | 0.047 |
Injury Severity Score | 1.110 (1.066–1.155) | < 0.001 | 1.091 (1.000–1.190) | 0.049 |
Sex, female | 2.791 (1.131–6.889) | 0.026 | 0.934 (0.100–8.705) | 0.952 |
Fall height | 1.089 (1.022–1.159) | 0.008 | 0.958 (0.820–1.118) | 0.584 |
Shock index | 22.489 (5.976–84.626) | < 0.001 | 0.833 (0.081–8.529) | 0.878 |
Initial hemoglobin | 0.741 (0.614–0.896) | 0.002 | 0.787 (0.522–1.188) | 0.254 |
CI, confidence interval.