Burden and predictions of hospitalized injuries in a low-middle income country: results from a Tunisian university hospital

ABSTRACT

Injuries are responsible for a high premature mortality and disability. They are poorly explored in low and middle income-countries. We aimed to estimate the burden of hospitalized injuries in the Monastir governorate (Tunisia) according to the nature of the injury, trends and projections of hospitalizations for injuries up until 2024, and to identify the distribution of this disease burden based on age and sex. We performed a descriptive study from 2002 to 2012 including all hospitalizations for injuries. Data were collected from morbidity and mortality register of the University Hospital of Monastir (Tunisia). We estimated the burden of injuries using the Disability Adjusted Life Years (DALYs). We described injuries (crude prevalence rate (CPR) and age standardized prevalence rate (ASR)), related mortality (lethality and standardized mortality ratio (SMR)), trends and prediction for 2024. A total of 18,632 hospitalizations for injuries representing 10% of all hospitalizations during study period were recorded. Per 1000 inhabitants per year, CPR was 3.36 and the ASR was 3.44. The lethality was of 17.5 deaths per 1000 injured inpatients per year and the SMR was of 2.95 (Confidence Interval of 95%: 2.64–3.29). Burden related to injuries was 2.36 DALYs per 1000 population per year, caused mainly by Years of Life Lost (83.4%), most frequent among men aged under 40 years. The predicted ASR for 2024 was 4.46 (3.81–5.23) per 1000 person-years. Injuries to the head was the most prevalent (20.7%) causing 67.7% of DALYs; and increasing by 226% through 2024. Injuries had a high prevalence and an important burden in a Tunisian university hospital. Prediction showed increased prevalence for 2024. Preventive measures and a trauma surveillance register should be implemented soon.

KEYWORDS:

• Epidemiology
• global burden of disease
• mortality
• prevalence
• trends
• wounds and injuries

1. Background

Injuries are a growing global health problem [1–3]. They are responsible for five million of deaths each year (9% of world’s deaths), exceeding those resulting from Human Immunodeficiency Virus and Acquired Immunodeficiency Syndrome, tuberculosis and malaria combined [1]. The burden of injuries is more pronounced among young people [4]. In 2017, it was the sixth leading cause of early death [5]. In addition, many of injured people who survive suffer from permanent disability. The vast majority (90%) of these deaths and disabilities are occurring in low- and middle-income countries (LMIC’s) [1,6].

An injury is an organic bodily region resulting from an acute exposure to energy or from an insufficiency of a vital element [2]. Injuries could be classified according to their mechanisms or to their consequences [7]. External mechanisms of injuries are classified into intentional (e.g. self-harm and violence), unintentional (e.g. fire and poisoning) and transport injuries [2,7,8]. Injuries have different categories according to their nature or consequences (e.g. fracture, wounds, and burns) [7].

To measure health, mortality alone is insufficient especially for injuries, which is responsible for an important disability [1]. Thus, using the Disability Adjusted Life Years (DALYs) is the most adequate. Indeed, DALYs is an epidemiologic indicator introduced by the Harvard School of Public Health in collaboration with The World Bank and World Health Organization (WHO) in 1993 to assess the global burden of disease (GBD). It combines in a single indicator, years of life lost (YLLs) from premature death and years of life lived with disabilities (YLDs) [9–11]. DALYs is a health gap that measure the state of a population’s health compared to an ideal situation [12].

Although injuries are responsible for a high global burden of disease, they were thought as ‘accidents’ or ‘random effects’ [2,13]. For this reason, injury prevention has not received the same global attention as others diseases especially in LMIC’s countries where they are considered as a neglected epidemic disease [14]. However, injuries are preventable and 39% of premature deaths from unintentional injuries can be reduced, prolonging about 37,000 lives if preventive interventions are effectively implemented [15]. The first step of the epidemiological approach to prevent injuries, like any other health problem, is to describe the characteristics and the magnitude of the problem [2]. Different studies in the world were done for that purpose mainly in high-income countries [12,16,17]. In LMICs, a few studies were published [3,18,19] and injuries are still poorly explored.

In Tunisia, according to the Institute for Health Metrics and Evaluation, injuries (especially road injuries) are the second cause of premature deaths and of DALYs in 2017 [20]. Injuries (all causes combined) represent almost 10% of the total Tunisian DALYs [20]. However, there is a shortage in studies exploring injuries in Tunisia.

We aimed to estimate the burden of hospitalized injuries in the Monastir governorate (Tunisia) according to the nature of the injury, trends and projections of hospitalizations for injuries up until 2024, and to identify the distribution of this disease burden of based on age and sex.

2. Methods

2.1. Study design

We have performed a cross-sectional descriptive study from 2002 to 2012 in the university hospital of Monastir. (Tunisia)

2.2. Study area and setting

Monastir governorate is a city in east central of Tunisia, which represents 0.7% of the total Tunisian territory, and its general population in 2015 was 560,002 inhabitants, corresponding to 5.02% of the Tunisian population [21].

The university hospital of Monastir (Tunisia) is a tertiary health center that include different departments implied on injury care: a mobile service of emergency and resuscitation unit linked to an emergency department, two general surgical departments, neuro-surgical department, orthopedic department and medical and anesthetic resuscitation department but we do not have a specialized department for burns. All severe injury cases from secondary-level healthcare centers in the governorate of Monastir are referred to our university hospital.

2.3. Study population

This study included patients hospitalized at the university hospital of Monastir (Tunisia) for injuries from 1 January 2002 to 31 December 2012.

Injuries were classified according to their nature and defined according to criteria proposed in the International Classification of Diseases, tenth edition (ICD-10) [7]. According to the ICD-10, there are two types of injury-related codes: The S and T codes relate to the nature (or consequences) of the injury, and the V, W, X, and Y codes relate to the mechanisms of injury [7]. So, all hospitalizations coded S and T referring to the 19^th chapter of the ICD-10 intitled ‘Injury, poisoning and certain other consequences of external causes’ [7], were included in our study. Appendix 1 represents the distribution of hospitalized cases of injuries according to their nature as mentioned in ICD-10 codes.

2.4. Data collection

We used an extract of the register of hospital morbidity and mortality data to identify all hospitalizations to hospital units for injuries. This register was implemented in the department of preventive medicine and epidemiology since 1995 and receives information quarterly from all departments of the university hospital of Monastir. For each admission, data were extracted for diagnosis, sex, age and death case. Diagnoses were coded according to ICD-10 [7].

2.5. Data analysis

Data were verified and analyzed using IBM SPSS Statistics version 20.0 software and Microsoft Excel. To describe the burden of injuries, we have used three types of indicators. First, for morbidity indicators, the crude prevalence rate (CPR) of injuries was calculated based on Tunisian national institute of statistics data [22] and was expressed per 1000 Inhabitants (Inh) and per year. Also, the age standardized prevalence rate (ASR) per 100,000 Person-Years (PY) was calculated using the world standard population according to the WHO statement of 2013 [23]. The injury proportion ratio (IPR) was calculated to compare injuries by age and sex. An IPR of one indicates that the proportion of observed cases for a characteristic is the same as the expected number based on the sum of the specific proportions of that characteristic [24].

Second, for mortality indicators, we used the lethality rate, defined as the number of dying cases on all diagnosed cases by disease, it was expressed per 1000 hospitalizations. Also, we calculated the standardized mortality ratio (SMR) through the indirect adjustment method [25]. The SMR represents the observed number of deaths in the study population divided by the expected number of deaths in the general population, assuming that the mortality rates for both populations are equivalent [26]. The corresponding confidence interval at 95% (CI95%) for each SMR was also calculated. The expected number of deaths was calculated by multiplying the death rates of the general population by the total number of the study population. An SMR greater than one denotes a higher mortality than what was expected.

According to the national burden of disease manual, the burden of injuries is estimated using in-hospital data [11]. We measured the burden of injuries by a combined metric: The DALYs. DALYs is the sum of YLDs and YLLs [10,27]. YLLs is the measure of years of life lost due to premature mortality. It is calculated by multiplying the number of deaths due to the given disorder at a particular age by the standard life expectancy at that age [8,27,28]. The estimation of YLDs for a given disorder is a product of epidemiological data that accommodates the number of people affected as well as the severity and disability associated with their symptoms. That is, YLDs are calculated by multiplying the prevalence of a disorder by its severity and comorbidity-adjusted disability weight [8,27,28]. The disability weight (DW) has a value anchored between zero, equivalent to full health, and one, equivalent to death. For this study, we used the same DW as in Global Burden of Diseases (GBD) 2013 [9]. For some missing ones we used a new DW developed in the Injury-VIBES (Validating and Improving Injury Burden Estimates) study [10]. The values of the weights assigned to each disorder are available in Appendix 2. For YLDs estimations, CI95% were considered. We estimate the trends and 2024 injuries prevalence predictions using the Age Period Cohort analysis based on Poisson log linear regression. To describe trends, we used the Poisson regression coefficient (b) and the corresponding standard error (SE). Quantitative variables were expressed by median and Interquartile Range (IQR) after testing normality by the Kolmogorov–Smirnov test.

A p-value of <0.05 was considered statistically significant.

2.6. Ethics

The study was conducted under Good Clinical Practice conditions and according to ethical standards collections. The register used for this study was approved by the regional scientific ethical committee (Monastir, Tunisia) since 1996. Register of morbidity data include only inpatient code and all documents were labelled accordingly to maintain anonymity.

3. Results

A total of 18,632 hospitalizations for injuries were recorded representing 10% of all hospitalizations in the study period. Men represented 70.70% of all cases (p < 10⁻³). The median age was 28 years (IQR: 16–48). The main number of hospitalizations corresponded to the age group 20–39 years for men and 1–19 years for women. The IPR was 1.42 in men and 0.58 in women. The highest IPR was noted among patients aged over 60 years (1.30 for men and 3.00 for women).

Prevalence, deaths, and burden related to hospitalizations for injuries according to age and sex: The overall CPR per 100,000 Inh was 336.0, it was 625.4 for patients aged more than 60 years, 472.7 for men, and 197.7 for women. The ASR was 344.9 per 100,000 PY. We notified 326 deaths related to injuries. Lethality was 17.50 per 1000 injured patients. The SMR was 2.95 (CI95%: 2.64–3.29). Total injury burden during study period was estimated at 13,029.7 DALYs corresponding to a mean of 1184.5 DALYs per year and to 235.5 DALYs per 100,000 populations per year composed by 196.5 YLLs and 39.1 (CI95%: 24.4–51.9) YDLs. The YLLs represented 83.4% of total DALYs. The highest burden was noted among patients aged under 40 years (254.0 DALYs per 100,000) (Table 1).

Table 1. Prevalence deaths, and burden related to hospitalizations for injuries according to age and sex (Monastir-Tunisia, 2002–2012).

	Prevalence					Deaths		Burden
	n (%)		IPR (CI95%)	CPR	ASR	n (lethality (‰))	SMR (CI95%)	YDLs* (CI95%)*	YLLs*	DALYs*
Overall	18632 (100.0)			336.0	344.9	326 (17.5)	2.9 (2.6–3.3)^$	39.1 (24.4–51.9)	196.5	235.5
†Age group (years)
0–19	5969 (32·1)		0.7 (0.7–0.7)	290.3		52 (8.7)		34.5 (21.3–45.2)	219.6	254.0
20–39	6194 (33·3)		1.1 (1.1–1.1)	329.2		115 (18.5)
40–59	3431 (18·5)		1.2 (1.2–1.3)	307.4		76 (22.1)		48.9 (31.3–64.1)	139.4	188.4
≥60	2990 (16·1)		1.8 (1.8–1.9)	625.4		83 (27.8)
^‡Sex
Men	13174 (70.7)		1.4 (1.4–1.4)	472.7	479.0	255 (19.4)	2.9 (2.5–3.2)^$	52.9 (31.8–67.7)	298.8	351.6
0–19	4152 (31·6)		0.7 (0.7–0.7)	392.3		34 (8.19)		49.9 (31.0–66.3)	329.86	379.78
20–39	5049 (38·4)		1.3 (1.2–1.3)	543.3		98 (19.41)
40–59	2371 (18·0)		1.2 (1.1–1.2)	418.9		64 (27.0)		61.72 (39.2–83.8)	220.8	282.5
≥60	1572 (12·0)		1.3 (1.3–1.4)	694.3		59 (37.5)
Women	5458 (29.3)		0.6 (0.6–0.6)	197.7	210.2	71 (13.0)	2.6 (2.0–3.3)^$	25.2 (15.7–33.0)	93.1	118.3
0–19	1817 (33·4)		0.7 (0.7–0.7)	182.2		18 (9.9)		19.6 (11.9–24.9)	107.1	126.6
20–39	1145 (21·0)		0.7 (0.6–0.7)	120.2		17 (14.8)
40–59	1060 (19·5)		1.4 (1.3–1.4)	192.7		12 (11.3)		38.4 (24.7–52.2)	59.0	97.4
≥60	1418 (27·4)		3.0 (2.8–3.2)	563.5		24 (16.9)

ASR: Age Standardized Prevalence Rate per/100.000 person-years. CI: 95% Confidence Interval. CPR: Crude Prevalence Rate per/100.000 inhabitants. DALYS: Disability-adjusted life years. IPR: Injury Proportion Ratio, calculated to compare injuries by age and sex (observed cases/expected number). †Distribution by age: p<10^−3;‡Distribution by sex: p<10⁻³. ^$Chi2 test for SMR: Standardized Mortality Ratio. *per 100,000 inhabitants per year; YLLs: Years of Life Lost to premature mortality, YLDs: Years Lived with Disability.

3.1. Distribution of prevalence, deaths, and burden of hospitalizations for injuries according to injury groups

Injuries to the head (20.7%, CI95%: [20.1; 21.3]), to the wrist and hand (16.2%, CI95%: [15.7; 16.7]), to the knee and lower leg (10.6%, CI95%: [10.2; 11.0]), to the thorax (9.8%, CI95%: [9.4; 10.2]), and to the hip and thigh (8.8%, CI95%: [8.4; 9.2]) represented 67% of hospitalizations. The median age at the time of admission differed by injuries nature: it was 3 years (IQR: 2–10) for poisoning by drugs, medicaments and biological substances, 29 years (IQR 16–50) for injuries to the head and 46 years (IQR: 22–71) for injuries to the hip and thigh (Figure 1).

Figure 1. Distribution of age at the time of admission for injuries (Monastir, Tunisia 2002–2012). Legend: this figure shows grouped age Boxplots according to the injury’s subgroups. Each boxplot represents the median age with the interquartile range (the first quartile in light gray and the third quartile in dark gray), and the extreme age values.

Distribution of injuries according to nature and age groups was detailed in Appendix 3. Sex ratio was 4.7 for injuries to the thorax and 0.8 for hospitalizations related to toxic effects of substances. According to the sex, the main injury groups causing hospitalizations were the injury to the head (22.0% and 17.4%, respectively, in men and women) followed by injuries to the wrist and hand (17.8% and 12.4%, respectively, in men and women). The ASR per 100 000 PY were 71.7 for injuries to the head, 54 for injuries to the wrist and hand, 37.7 for injuries to the knee and lower leg and 33.3 for injuries to the thorax. Two injury groups were responsible of the majority death cases: injury to the head (233 deaths with an SMR of 10.2 (CI95%: 8.9–11.6)) and burns and corrosions (38 deaths with an SMR of 11.16 (CI95%: 7.7–15.3)). Injuries to the head followed by burns and corrosions were the largest contributors to YLLs Figure 2. Injuries to the head followed by injuries to the hip and thigh had the highest disability with YLDs of 11.8 (7.8–16.5), and 6.5 (4.2–90.6), respectively (Table 2).

Figure 2. Main injury groups responsible for total burden caused by injuries in Monastir-Tunisia (2002–2012). Legend: A: DALYs, B: YLLs; C: YLDs. data represent the percentage of the main injury groups responsible for the total DALYs (DALYs: disability-adjusted life years), the total YLLs (years of life lost to premature mortality) and the total YLDs (years lived with disability.

Table 2. Prevalence, deaths and burden of hospitalized injuries according to their nature (Monastir, Tunisia: 2002–2012).

Injuries subgroups	n (%)			Prevalence		Deaths		Burden
	All	Men	Women	CPR	ASR	n (lethality (‰))	SMR (CI95%)	YDLs* (CI95%)*	YLLs*	DALYs*
Injuries to the head	3849(20.7)	2901(22.0)	948 (17.4)	69.3	71.7	233 (60.53)	10.2 (8.9–11.6)	11.8 (7.8–16.5)	147.6	159.4
Intracranial injury	2954 (15.9)			53.1	55.3	139 (47.05)	7.9 (6.7–9.4)	11.4 (7.515.7)	84.5	95.9
Injuries to the neck	165 (0.9)	87 (0.7)	78 (1.4)
Injuries to the thorax	1831 (9.8)	1509(11.5)	322 (5.9)	33.1	33.3	7 (3.8)	0.6 (0.3–1.3)	2.3 (14–3.3)	5.1	7.4
Open wound of thorax	650 (3.5)			11.7	11.4			0.07 (0.02–0.14)	1.1	1.1
Injuries to the abdomen. lower back. lumbar spine and pelvis	1306 (7.0)	931 (7.1)	375 (6.9)	23.6	24.1	10(7.7)	1.3 (0.6–2.4)	3.9 (3.22–4.70)	4.7	8.3
Injury of intra-abdominal organs	825 (4.4)			14.9	15.1	9(10.9)	1.8 (0.84–3.5)	2.7 (2.4–3.0)	4.4	7.1
Fracture of lumbar spine and pelvis	197 (1.1)			3.6	3.9			1.0 (0.7–1.4)		1
Injuries to the shoulder and upper arm	919 (4.9)	597 (4.5)	322 (5.9)	16.6	17.6	1 (1.09)	0.18 (0.01–1.02)	0.7(0.43–1.06)	0.1	0.8
Dislocation. sprain and strain of joints and ligaments	177 (0.9)			3.2	3.3			0.3 (0.2–0.5)		0.3
Fracture	544 (2.9)			1.0	10.8			0.2(0.1–0.3)	0.1	0.3
Injuries to the elbow and forearm	1076 (5.8)	793 (6.0)	283 (5.2)	19.4	19.7	1 (0.93)	0.16 (0.01–0.87)	0.7 (0.4–1.1)	0.02	0.7
Fracture	667 (3.6)			12.0	12.3			0.3 (0.2–0.5)	0.02	0.4
Open wound	178 (1.0)			3.2	3.1			0.02 (0.01–0.04)		0.02
Injuries to the wrist and hand	3016 (16.2)	2340(17.8)	676 (12.4)	54.5	54.1	3 [1]	0.2 (0.0–0.5)	3.0 (1.5–4.3)	1.9	4.9
Open wound of wrist and hand	1116 (6.0)			2.2	19.6			0.1 (0.0–0.2)		0.12
Injuries to the hip and thigh	1643 (8.8)	1066 (8.1)	577 (10.6)	29.6	33.4	8 (4.87)	0.82 (0.35–1.62)	6.5 (4.2–9.1)	07	7.2
Fracture of femur	1253 (6.7)			22.6	25.8	8 (6.38)	1.08 (0.46–2.12)	5.8 (3.9–8.1)		5.8
Injuries to the knee and lower leg	1974 (10.6)	1339(10.2)	635 (11.6)	35.6	37.7	1 (0.51)	0.08 (0.01–0.5)	2.42 (1.5–3.5)		2.4
Fracture of lower leg. including ankle	995 (5.3)			18.0	19.4			0.9(0.6–1.3)		0.9
Injuries to the ankle and foot	375 (2.0)	280 (2.1)	95 (1.7)	6.8	7.1	2 (5.3)	0.9 (0.1–3.2)	0.2 (0.1–0.3)	0.1	0.3
Effects of foreign body entering through natural orifice	526 (2.8)	312 (2.4)	214 (3.9)	9.4	9.2	0		1.7		1.7
Foreign body in respiratory tract	497 (2.7)			8.9	8.6			1.6		1.6
Burns and corrosions	575 (3.1)	336 (2.6)	239 (4.4)	1.35	10.06	38 (66.1)	11.2 (7.7–15.3)	1.4 (0.9–1.9)	23.6	25.0
Burns and corrosions of multiple body regions	549 (2.9)			9.88	9.61	36 (65.6)	11.1 (7.7–15.3)	1.3 (0.91–1.88)	22.5	23.8
Poisoning by drugs. medicaments and biological substances	708 (3.8)	376 (2.9)	332 (6.1)	12.60	11.81	7 (9.89)	1.7 (0.7–3.4)	2.1 (1.40–2.89)	7.1	9.2
Toxic effects of substances chiefly nonmedicinal as to source	552 (3.0)	238 (1.8)	314 (5.8)	9.96	9.49	7 (12.7)	2.1 (0.9–4.4)	1.6 (1.1–2.3)	5.2	6.8
Toxic effect of soaps and detergents	506 (2.7)			9.1	8.6			1.5 (1.0–2.1)		1.5
Others	117 (0.6)	69 (0.5)	48 (0.9)	5.0	5.5	8(28.4)	4.8(2.1–9.4)	0.6 (0.4–0.8)	0.6	1.2

The 21 groups of injuries and their main subgroups are represented by their absolute and relative frequencies coded and ranked according to the ICD-10.ICD-10: International Classification of Diseases 10th revision version. ASR: Age Standardized Prevalence Rate per/100.000 person-years. CI: Confidence Interval. CPR: Crude Prevalence Rate per/100.000 inhabitants. DALYS: disability-adjusted life years. SMR: Standardized Mortality Ratio. *: per 100,000 inhabitants. YLLs: years of life lost to premature mortality. YLDs: years lived with disability.

3.2. Trends and predictions to 2024 of hospitalizations for injuries

The overall trends of hospitalizations for injuries were significantly increasing (b = 0.008, p = 0.001). Trends were significantly increasing for men (b = 0.018; p < 10⁻³) and for all age groups (p < 10⁻³). Trends was stable for women (p = 0.412). The highest IPR was recorded in 2010 (1.30) and in 2011 (1.15). Month and weekday at higher risk were August (IPR = 1.14) and Monday (IPR = 1.12).

By 2024, the ASR per 100,000 PY would be 446.3 (381.4–523.2), 566.2 (472.9–681.2) for men, 348.3 (262.0–463.6) for women and 233.8 (162.9–337.6) for injuries to the head Table 3. In 2024, the number of injuries in elderly was estimated to be more than 7500 cases per year equal to 21 cases DALYs (Figure 3).

Figure 3. Trends and predictions for 2024 of hospitalizations for injuries (Monastir, Tunisia). Legend: this figure shows trends of the number of injuries between 2002 –2012 and the projections until 2024 using Poisson log linear regression.

Table 3. Trends and prediction in hospitalizations for injuries by nature (Monastir-Tunisia 2002–2012).

Injury subgroups	Slope (SE)	ASR 2024/100.000 person-years (CI95%)
		Overall	Men	Women
Head Injuries	0.048 (0.0051)*	233.8 (162.9–337.6)	297.4 (195.4–458.5)	185.6 (93.6–370.2)
Injuries to the wrist and hand	−0.088 (0.0059)*	17.9 (10.9–30.2)	26.2 (19.5–36.4)	12.1 (4.8–29.9)
Injuries to the knee and lower leg	0.013 (0.0071)*	95.9 (58.6–157.2)	45.5 (24.1–86.9)	219.7 (108.3–444.3)
Injuries to the thorax	0.150 (0.0079)*	361.2 (239.9–555.6)	481.0 (316.6–754.5)	372.4 (127.3–1106.8)
Total	0.008 (0.011)*	446.3 (381·4–523·2)	566.2 (472·1–681·8)	348.3 (262·0–463·6)

ASR: Age Standardized Prevalence Rate per/100.000 person-years; *: CI_95% : 95% Confidence Interval ; p<0.05 ;SE : Standard Error.

4. Discussion

This study shows that burden related to injuries was estimated at 235.55 DALYs per 100,000 Inhabitants per year, caused mainly by YLLs (83.4%), most frequent among men aged under 40 years. Injuries to the head was the most prevalent and caused 67.7% of DALYs; it increased over time with a predicted rise rate of 226% by 2024. Injuries in our study represented 10% of all hospitalizations, and caused 11,832.5 total hospitalizations days each year. The predicted ASR in 2024 will increase by 18.2% for men and 65.7% for women.

4.1. Burden of injuries

We estimated the total burden of injuries expressed by DALYs as relatively high in Monastir University Hospital (235.55 per 100,000 Inhabitants per year). Injury burden was estimated to be larger in the GBD Tunisia profile of 2010 than in our study [20]. Methodological differences in the calculation of the DALYs and in the data source (our study was based only on in hospital data) could explain this variation. Our results were lower than those described in Korea (3,170 per 100,000) in 2010 and higher than in Qatar (43 per 100,000) in the same period [18,29]. The premature death predominated over disability, indeed YLLs represented 83.4% of the overall DALYs. This was true for the most of injury groups. Others studies also reported the same results [7,11,18]. The main groups responsible for the DALYs specifically for YLLs were injuries to the head (more than 3/5) followed by burns and corrosions. Concerning the disability, injuries to the head and injuries to the hip and thigh had the highest YLDs. At global level, injuries to the head were also described as the largest cause of death and disability [30]. Burns were also responsible of an important DALYs in others LMIC’s [31,32]. The burden of hip fracture was estimated to be larger in Europeans and North Americans, and causes mainly disability. Indeed, the majority of hip fracture occurs in high-income countries [33]. The burden of injuries was higher in men than in women and in patients aged less than 40 years than in others. This was in accordance with the majority of others publications concerning injuries [6,29,32,34].

4.2. Prevalence of injuries

Our study revealed that hospitalizations due to injuries accounted for 10% of all hospitalizations occuring mainly among men aged under than 40 years. In comparison, a study conducted in Malawi found a hospitalization rate related to injuries of 3.4%, primarily among boys and young men [3]. We identified poisoning, burns and effects of foreign body entering through natural orifice as the three most prevalent injury types among children and adolescent. A study conducted in Brazil revealed that burns predominately affected children under 5 years old [31]. The highest CPR and lethality were observed among elderly aged more than 60 years. Similarly, another study in a Korean hospital showed that the incidence of trauma increased after 60 years old and that the age more than 55 years is an independent factor of trauma mortality [35]. According to the 2004 GBD report, deaths were more frequent in the age group of 15–59 years old [32]. This may be attributed to the improvement of the healthcare services given for young and adult population. Nonetheless, it emphasizes the significance of the implementation of specialized geriatric units in the health care centers. Injuries to the head had the highest CPR and ASR (71.69 per 100,000 person-years).

According to the GBD Study 2016, the ASR per 100,000 of traumatic brain injury was of 699 in Tunisia, 782 in North Africa and Middle East and 544 in high-income countries [36]. Taking into account that the GBD study used outpatient and inpatient data and estimations from specific models rather than direct data, and that our data are from a regional register, we can understand this big difference.

4.3. Mortality related to injuries

The SMR in our study was significantly higher than one, for the majority of injuries groups indicating that the observed number of deaths was higher than the expected one. The highest lethality and SMR were observed for burns and corrosions followed by injuries to the head. However, in numbers, injuries to the head caused 71% of all deaths followed by burns (11%). In Europe, traumatic brain injury caused 37% of all injury-related deaths 16 and in a Nigerian Teaching Hospital it caused 31% of trauma deaths [37]. For burns others, studies showed a smaller in-hospital mortality rate [31,37].

4.4. Trends and prediction of injuries

An alarming increasing trend for overall injuries was noted between 2002 and 2011. This was in accordance with the trends in low- and middle-income countries. In contrast, in many high-income countries, trends of injury have been decreasing reflecting the efficacy of preventive measures [7,13,38].

We observed an increasing predicted ASR for overall injuries with a higher percentage change in women compared to men. Indeed, women nowadays are more exposed to external risks causing injuries (e.g. rood traffic injuries and work) [20]. Globally, without prevention efforts, by the year 2030, injuries morbidity and mortality lie between 5% increase and 6% decrease [39].

4.5. Limitations

To the best of the authors’ knowledge, this is the first Tunisian study treating the burden and epidemiological profile of different injuries’ groups. In spite of its originality, this study has some limitations. We had selection bias, indeed we used data only from a hospital registry. Generalizability to entire population is therefore limited, to injuries requiring hospitalization. The period of the study was limited to 11 years (2002–2012) because data codification was incomplete after this period and the rate of missing data was high. We included injuries according to the nature of lesion (i.e. ICD-10 codes S and T). Causes of injuries (ICD-10 codes V, W, X and Y) were not studied. Besides, we assessed outcomes only during hospital stay so follow-up of longer-term rates of morbidity and mortality, was not recorded so we have only used short-term disability weight for the calculation. For that, the YLDs could be underestimated. Finally, prediction for 2024 could be distorted by the political (Tunisian revolution in December 2010–January 2011) and health (Coronavirus disease pandemic) context of the country. Efforts to complete registry data collection are underway in order to be able to compare real data with predicted ones and to predict injury burden for 2030 and 2040.

In conclusion, this study confirmed that injuries are responsible for an important burden in a Tunisian governorate especially as a cause of premature death mainly among men. Injuries to the head were identified as the main group in terms of prevalence, mortality and morbidity. An over-all increasing trend of injuries was recorded between 2002 and 2012 and a positive percentage of change of ASR is predicted for 2024. These outcomes are in accordance with the published data about injuries in LMICs in which preventive measures are poor. Basing on our findings and on a literature review a number of recommendations should be taken to curb the growing burden of injuries in Tunisia. Enforcing existing laws and improving the infrastructure and the public transportation system. Improving the pre-hospital and early care for injured patients. Strengthening education courses about trauma for all the healthcare workers involved in injuries and about first aid to the general population. Also, education sessions in schools are very important in order to prevent violence and so traumatism among teenagers. Moreover, setting up a national surveillance system seem to be an urgent step to the management of injury burden.

5. Authors’ contributions

M.k., C.B. W.D., H.A., I.Z., M.B.F, and ASB designed the study. M.K., and ASB preformed figures. M.k., whrite the initial manuscript. B. M.F, I.A. and S.N. discussed results. M.k., C.B. W.D., H.A., I.Z., M.B.,A.G, A.M and ASB all made contribution to writing the manuscript. All authors reviewed the manuscript.

List of abbreviations

ASR Age-Standardized prevalence Rate

CI Confidence Interval

CPR Crude Prevalence Rate

DALYs Disability Adjusted Life Years

DW disability weights

GBD global burden of disease

ICD-10 International Classification of Diseases from the tenth revision

IQR Interquartile Range

IPR Injury Proportion Ratio

LMIC’s Low- and Middle-Income Countries

SMR Standardized Mortality Ratio

WHO World Health Organization

YLDs Years Lived with Disability

YLLs Years of Life Lost

Acknowledgments

We would like to extend our sincere gratitude to the language model, CHATGPT 3.5, for its invaluable assistance in the correction and improvement of our scientific paper.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors reported there is no funding associated with the work featured in this article.

Appendix 1:

Injuries subgroup distribution according to their nature and corresponding International Classification of Diseases, 1^,th revision codes (Monastir-Tunisia 1,- 1,)

Table

ICD-10* Wording	ICD-10 Code(s)	N (%)
Injuries to the head	S00-S09	(20.7)
Intracranial injury	S06	2954 (15.9)
Other and unspecified injuries of head	S09	558 (3.0)
Injuries to the neck	S10-S19	165 (0.9)
Injuries to the thorax	S20-S29	1831 (9.8)
Superficial injury of thorax	S20	671 (3.6)
Open wound of thorax	S21	650 (3.5)
Injuries to the abdomen, lower back, lumbar spine and pelvis	S30-S39	1306 (7.0)
Injury of intra-abdominal organs	S36	825 (4.4)
Fracture of lumbar spine and pelvis	S32	197 (1.06)
Injuries to the shoulder and upper arm	S40-S49	919 (4.9)
Dislocation, sprain and strain of joints and ligaments of shoulder girdle	S43	177 (0.9)
Fracture of shoulder and upper arm	S42	544 (2.9)
Injuries to the elbow and forearm	S50-S59	1076 (5.8)
Fracture of forearm	S52	667 (3.6)
Open wound of forearm	S51	178 (1.0)
Injuries to the wrist and hand	S60-S69	3016 (16.2)
Superficial injury of wrist and hand	S60	1381 (7.4)
Open wound of wrist and hand	S61	1116 (6.0)
Injuries to the hip and thigh	S70-S79	1643 (8.8)
Superficial injury of hip and thigh	S70	370 (2.0)
Fracture of femur	S72	1253 (6.7)
Injuries to the knee and lower leg	S80-S89	1974 (10.6)
Fracture of lower leg, including ankle	S82	995 (5.3)
Superficial injury of lower leg	S80	414 (2.2)
Injuries to the ankle and foot	S90-S99	375 (2.0)
Injuries involving multiple body regions	T00-T07	52 (0.3)
Injuries to unspecified part of trunk, limb or body region	T08-T14	37 (0.2)
Effects of foreign body entering through natural orifice	T15-T19	526 (2.8)
Foreign body in respiratory tract	T17	497 (2.7)
Burns and corrosions	T20-T32	575 (3.1)
Burns and corrosions of multiple body regions	T29	549 (2.9)
Frostbite	T33-T35	1 (0.0)
Poisoning by drugs, medicaments and biological substances	T36-T50	708 (3.8)
Poisoning by diuretics and other and unspecified drugs, medicaments and biological substances	T50	705 (3.8)
Toxic effects of substances chiefly nonmedicinal as to source	T51-T65	552 (3.0)
Toxic effect of soaps and detergents	T55	506 (2.7)
Other and unspecified effects of external causes	T66-T78	15 (0.1)
Certain early complications of trauma	T79-T79	7 (0.0)
Complications of surgical and medical care, not elsewhere classified	T80-T88	1 (0.0)
Sequelae of injuries, of poisoning and of other consequences of external causes	T90-T98	4 (0.0)
Total		18632 (100.0)

The 21 groups of injuries and their main subgroups are represented by their absolute and relative frequencies, coded and ranked according to the *ICD-10 (International Classification of Diseases 10th revision version).

Appendix 2:

Disability weights used for YLD estimations

Table

ICD-10 Code	Nature of injury	YLD score (CI95%)*
S00-S09	Injuries to the head
S00	Superficial injury of any part of the body	0·100 (0·053–0·148)
S01	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S02	fracture of the Face bone: short or long term, with or without treatment	0·067 (0·044–0·097)
S03	Other injuries of muscles and tendons	0·008 (0·003–0·015)
S05	Injury to eyes: short term	0·054 (0·035–0·081)
S06	Traumatic brain injury Severe: short term, with or without treatment 4	0·214 (0·141–0·297)
S08	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S09	Other and unspecified injuries of head	0·008 (0·003–0·015)
S10-S19	Injuries to the neck
S10	Superficial injury of any part of the body	0·100 (0·053 to 0·148)
S11	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S12	Fracture of Vertebral column: short or long term, with or without treatment	0·111 (0·075–0·156)
S13	Other injuries of muscles and tendons	0·008 (0·003–0·015)
S14	Spinal cord lesion At neck: treated	0·589 (0·415–0·748)
S16	Other injuries of muscles and tendons	0·008 (0·003–0·015)
S17	Crush injury: short or long term, with or without treatment	0·132 (0·089–0·189)
S19	Other and unspecified injuries	0·196 (0·168–0·223)
S20-S29	Injuries to the thorax
S20	Superficial injury of any part of the body Contusion of any part of the body	0·100 (0·053–0·148)
S21	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S22	Sternum or one or two ribs: short term, with or without treatment+++	0·103 (0·068–0·145)
S23	Other injuries of muscles and tendons	0·008 (0·003–0·015)
S24	Spinal cord lesion Below neck: treated	0·296 (0·198–0·414)
S26	Severe chest injury Short term, with or without treatment	0·369 (0·248–0·501)
S28	Severe chest injury Short term, with or without treatment	0·369 (0·248–0·501)
S29	Other and unspecified injuries	0·196 (0·168–0·223)
S30-S39	Injuries to the abdomen, lower back, lumbar spine and pelvis
S30	Superficial injury of any part of the body Contusion of any part of the body	0·100 (0·053–0·148)
S31	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S32	Fracture of Pelvis: short term	0·279 (0·188–0·384)
S33	Other injuries of muscles and tendons	0·008 (0·003–0·015)
S35-S37*	Internal hemorrhage in abdomen and pelvis	0·182 (0·162–0·203)
S38	Crush injury: short or long term, with or without treatment	0·132 (0·089–0·189)
S40–49	Injuries to the shoulder and upper arm
S40	Superficial injury/Contusion of any part of the body	0·100 (0·053 to 0·148)
S41	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S42	Fracture of Clavicle, scapula, or humerus: short or long term, with or without treatment	0·035 (0·021–0·053)
S43	Shoulder: long term, with or without treatment	0·062 (0·041–0·088)
S45	Open wound: short term, with or without treatment+++	0·006 (0·002–0·012)
S47	Crush injury	0·132(0·089–0·189)
S50-S59	Injuries to the elbow and forearm
S50*	Contusion of any part of the body	0·100 (0·053–0·148)
S51	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S52	Fracture of Radius or ulna: short term, with or without treatment	0·028 (0·016–0·046)
S53	Shoulder: long term, with or without treatment	0·062 (0·041–0·088)
S54	Injured nerves Short term	0·100 (0·067–0·140)
S60-S69	Injuries to the wrist and hand
S60	Contusion of any part of the body	0·100 (0·053–0·148)
S61	Open wound	0·006 (0·002–0·012)
S62	Fracture of Hand: short term, with or without treatment	0·010 (0·005–0·019)
S63*	Dislocation/strain/sprain of wrist/hand/fingers	0·254
S64	Nerve injury short term	0·100(0·067–0·140)
S66	Other injuries of muscles and tendons	0·008 (0·003–0·015)
S68	Amputation wrist and hand	0·123 (0·081–0·176)
S70-S79	Injuries to the hip and thigh
S70*	Superficial injury of any part of the body	0·100 (0·053–0·148)
S71	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S72	Fracture Neck of femur: short term, with or without treatment	0·258 (0·172–0·356)
S73	Dislocation Hip: long term, with or without treatment	0·016 (0·008–0·028)
S76	Other injuries of muscles and tendons	0·008 (0·003–0·015)
S78	Amputation of One leg: long term, with treatment	0·039 (0·023–0·059)
S80-S89	Injuries to the knee and lower leg
S80*	Superficial injury/contusion of any part of the body	0·100 (0·053–0·148)
S81	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S82	Fracture of Patella, tibia or fibula, or ankle: short term, with or without treatment	0·050 (0·032–0·075)
S83	Dislocation Knee: long term, with or without treatment	0·113 (0·075–0·160)
S84	Nerve injury short term	0·100(0·067–0·140)
S86	Other injuries of muscles and tendons	0·008 (0·003–0·015
S90-S99	Injuries to the ankle and foot
S90*	Superficial injury/contusion of any part of the body
S91	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
S92	Fracture of Foot bones: short term, with or without treatment	0·026 (0·015–0·043)
S93	Other injuries of muscles and tendons	0·008 (0·003–0·015)
S94	Injured nerves Short term	0·100 (0·067–0·140)
S98	Amputation Toe One leg: long term, with treatment	0·039 (0·023–0·059)
S99	Other injuries of muscles and tendons	0·008 (0·003–0·015)
T00-T07	Injuries involving multiple body regions
T00*	Superficial injury of any part of the body	0·100 (0·053–0·148)
T01	Open wound: short term, with or without treatment	0·006 (0·002–0·012)
T02- T07*	Other and unspecified injuries	0·196 (0·168–0·223)
T08-T14*	Injuries to unspecified part of trunk, limb or body region	0·196 (0·168–0·223)
T15-T19	Effects of foreign body entering through natural orifice
T15	Injury to eyes: short term	0·054 (0·035–0·081)
T16*	Foreign body	0·180
T17*	Foreign body in respiratory system	0·180
T18*	Foreign body in GI and urogenital system	0·180
T19*	Foreign body	0·180
T20-T32	Burns and corrosions
T20-T28	≤20% of total surface area without lower airway burns: short term, with or without treatment	0·141 (0·094–0·196)
T29	≥20% of total surface area or ≥ 10% of total surface area if head or neck, or hands or wrist are involved: long term, with treatment	0·135 (0·092–0·190)
T33-T35	Frostbite	0·196 (0·168–0·223)
T36-T50	Poisoning: short term, with or without treatment	0·163 (0·109–0·227)
T51-T65	Poisoning: short term, with or without treatment	0·163 (0·109–0·227)
T66-T79*	Other and unspecified effects of external causes	0·196 (0·168–0·223) 0·196 (0·168–0·223) 0·196 (0·168–0·223)
T80-T88	Complications following therapeutic procedures
T90-T98	Sequelae of injuries, of poisoning and of other consequences of external causes
T93	Open wound: short term, with or without treatment	0·006 (0·002–0·012)

*CI: 95% confidence interval; YLD (years lived with disability); *score from the Injury-VIBES (Validating and Improving Injury Burden Estimates) study.¹⁰

Appendix 3:

Distribution of hospitalizations by injury category and age class (Monastir-Tunisia 3,- 3,)

Table

	Distribution by age class N (%)
	<19 years	19–39 years	40–59 years	≥60 years
Overall	5969 (32.1)	6194 (33.3)	3431 (18.5)	2990 (16.1)
Men	4152(31.6)	5049(38.4)	2371(18.0)	1572(12.0)
Women	1817(33.4)	1145(21.0)	1060(19.5)	1418(27.4)
Injuries subgroups
Injuries to the head	1201(31.3)	1212(31.6)	755(19.7)	665(17.3)
Intracranial injury	956(32.5)	862(29.3)	584(19.9)	538(18.3)
Other and unspecified injuries of head	131(23.5)	222(39.8)	134(24.0)	71(12.7)
Injuries to the wrist and hand	805(26.7)	1378(45.7)	554(18.4)	279(9.3)
Superficial injury of wrist and hand	365(26.4)	577(41.8)	286(20.7)	153(11.1)
Open wound of wrist and hand	316(28.3)	566(50.7)	169(15.1)	65(5.8)
Injuries to the knee and lower leg	514(26.1)	602(30.5)	425(21.6)	431(21.9)
Fracture of lower leg, including ankle	234(23.5)	282(28.4)	214(21.5)	264(26.6)
Superficial injury of lower leg	124(30.0)	139(33.7)	84(20.3)	66(16.0)
Injuries to the thorax	376(20.5)	851(46.5)	387(21.1)	216(11.8)
Superficial injury of thorax	106(15.8)	272(40.5)	182(27.1)	111(16.5)
Open wound of thorax	129(19.8)	379(58.3)	98(15.1)	44(6.8)
Injuries to the hip and thigh	364(22.2)	345(21.0)	319(19.5)	612(37.3)
Superficial injury of hip and thigh	81(21.9)	95(25.7)	95(25.7)	99(26.8)
Fracture of femur	277(22.2)	242(19.4)	223(17.8)	508(40.6)
Injuries to the abdomen, lower back, lumbar spine and pelvis	371(28.5)	458(35.1)	298(22.9)	177(13.6)
Injury of intra-abdominal organs	253(30.7)	276(33.5)	201(24.4)	93(11.3)
Open wound of abdomen, lower back and pelvis	38(21.0)	99(54.7)	28(15.5)	16(8.8)
Injuries to the elbow and forearm	419(39.0)	328(30.5)	175(16.3)	153(14.2)
Fracture of forearm	267(40.1)	176(26.4)	117(17.6)	106(15.9)
Open wound of forearm	57(32.0)	94(52.8)	19(10.7)	8(4.5)
Injuries to the shoulder and upper arm	266(28.9)	261(28.4)	187(20.3)	205(22.3)
Dislocation, sprain and strain of joints and ligaments of shoulder girdle	43(24.3)	63(35.6)	40(22.6)	31(17.5)
Open wound of shoulder and upper arm	26(25.5)	45(44.1)	21(20.6)	10(9.8)
Poisoning by drugs, medicaments and biological substances	613(87.9)	62(8.9)	13(1.9)	9(1.3)
Poisoning by diuretics and other and unspecified drugs, medicaments and biological substances	26(25.5)	45(44.1)	21(20.6)	10(9.8)
Burns and corrosions	279(48.7)	183(31.9)	79(13.8)	32(5.6)
Burns and corrosions of multiple body regions	260(47.5)	178(32.5)	78(14.3)	31(5.7)
Toxic effects of substances chiefly nonmedicinal as to source	261(47.5)	225(40.8)	42(7.5)	23(4.2)
Toxic effect of soaps and detergents	245(48.4)	211(41.7)	33(6.5)	16(3.2)
Effects of foreign body entering through natural orifice	325(62.3)	103(19.7)	61(11.7)	33(6.3)
Foreign body in respiratory tract	314(63.7)	92(18.7)	58(11.8)	29(5.9)
Injuries to the ankle and foot	101(26.9)	119(31.7)	78(20.8)	77(20.5)
Others	74(26.7)	67(24.2)	58(20.9)	78(28.2)

For every injury category, admissions are distributed by age class.