In-hospital vs out-of-hospital cardiac arrest in the Arab Asian countries: A contemporary review of the literature

Abstract

BACKGROUND

Cardiac arrest is a critical condition characterized by abrupt cessation of cardiac function, resulting in reduced oxygen delivery to vital organs and rapid progression to death if not timely treated. Despite advances in medical science and resuscitation techniques, cardiac arrest remains a significant burden globally, with survival rates remaining low. Comprehensive research on cardiac arrest, particularly comparisons between in-hospital cardiac arrest (IHCA) and out-of-hospital cardiac arrest (OHCA), is limited.

AIM

To compare the survival rates, return of spontaneous circulation (ROSC), survival to discharge, and neurological outcomes after IHCA and OHCA in Arab Asian countries.

METHODS

We systematically searched PubMed, Medline, EMBASE and Google Scholar (2000-2024) using keywords (“IHCA”, “OHCA”, “cardiac arrest”, “Middle East”, “Arab”, “Asian”) in titles/abstracts. The inclusion criterion was observational studies on adults (≥ 18 years) in Arab Asian countries reporting relevant outcomes. The exclusion criteria were narrative reviews, non-Arab Asian studies, non-English publications, inaccessible full texts, pediatric-only populations, and studies lacking outcome data.

RESULTS

In total, 44 observational studies from nine Arab Asian countries comprising 32535 participants were included. This review highlights the substantial variability in cardiac arrest outcomes in Asian countries. OHCA mortality rates were alarmingly high in several nations, with Kuwait (99%), Bahrain (98.8%), and Qatar (97.6%) reporting the highest figures. In contrast, the Kingdom of Saudi Arabia (KSA) had a markedly lower OHCA mortality rate (8.2%). The rates of ROSC also varied, with Qatar achieving the highest (34.4%) and Kuwait the lowest (3.3%). Survival to hospital discharge ranged from 1.2% in Bahrain to 18.7% in Kuwait, with Qatar also reporting favorable rates (17.5%). For IHCA, mortality was 73.6% in the United Arab Emirates (UAE) and 72.8% in KSA, whereas Lebanon and Iraq reported higher rates of 94.6% and 88%, respectively. ROSC rates were the highest in Lebanon (55.9%) and the UAE (51.3%). Neurological outcome reporting has been inconsistent, although Qatar reported a high rate (68.6%) for OHCA survivors. Comparative data showed generally better survival and neurological outcomes with IHCA than with OHCA.

CONCLUSION

This systematic review underscores the clear disparity in survival outcomes between IHCA and OHCA in Arab Asian countries, with IHCA demonstrating superior outcomes. Despite progress in some countries, outcomes remain suboptimal compared with international standards. Future multicenter studies with standardized methodologies are required to generate high-quality evidence and provide region-specific interventions for cardiac arrest management.

Key Words: In-hospital; Cardiac arrest; Out-of-hospital; Resuscitation; Cardiopulmonary resuscitation; Arab; Asian countries

Core Tip: Without prompt resuscitation after cardiac arrest, vital organs deteriorate rapidly, culminating in irreversible organ damage and death. Cardiopulmonary resuscitation (CPR) and management of the underlying causes are essential to achieve return of spontaneous circulation. A systematic review comparing in-hospital and out-of-hospital cardiac arrest outcomes across Arab Asian nations is lacking. The outcomes remain suboptimal in this region compared with international standards. Improving community preparedness through CPR and automated external defibrillators training, strengthening the emergency medical services infrastructure, and standardizing post-arrest care protocols are vital steps toward improving survival rates. Future high-quality multicenter studies with standardized methodologies are required.

INTRODUCTION

Cardiac arrest is a sudden, life-threatening event characterized by the cessation of cardiac mechanical activity, leading to an immediate loss of systemic perfusion and oxygen delivery[1]. Without prompt resuscitation to restore circulation, vital organs deteriorate rapidly, culminating in irreversible organ damage and death. Consequently, immediate cardiopulmonary resuscitation (CPR) and management of the underlying cause are essential to achieve return of spontaneous circulation (ROSC)[2]. Despite substantial advancements in resuscitation techniques and prehospital and in-hospital critical care, cardiac arrest continues to impose a significant burden globally, with persistently poor survival rates[3].

Survival outcomes after a cardiac arrest are significantly influenced by the setting in which the event occurs. In-hospital cardiac arrest (IHCA), in which patients have immediate access to healthcare professionals and shorter collapse-to-treatment time, shows markedly higher survival rates[4] than out-of-hospital cardiac arrest (OHCA), where timely intervention and the quality of initial resuscitation efforts are often suboptimal[5]. Notably, most of these events occur outside hospitals. In the United States, over 356000 OHCA cases occur annually, with a survival rate of less than 10%[6]. In contrast, survival rates for IHCA are significantly higher, ranging from 18% to 30%[7]. Similarly, European data show an overall OHCA survival rate of 10.3%, whereas IHCA survival reaches 23%[8]. Recent reports indicate significant variability in the incidence of OHCA, ranging from 6.0 to 45.7 per 100000 individuals, with corresponding survival rates varying widely between 1.6% and 32%[9]. Furthermore, high-income countries report a lower estimated OHCA incidence (50-60 per 100000 individuals) and relatively better survival outcomes, whereas low-income countries have a significantly higher OHCA burden (166 per 100000 individuals) and poorer outcomes[10]. Various factors influence survival and neurological outcomes following cardiac arrest in both OHCA and IHCA cases, and play a critical role in determining outcomes[4,11].

Outcomes reported for both OHCA and IHCA in the Middle East and North Africa region are consistent with findings from Western literature. Although studies have been conducted in this region, a systematic review that specifically compares OHCA and IHCA outcomes across Arab Asian nations is lacking. For instance, a study in Jordan highlighted a significant disparity, with survival rates of 2.9% for patients with OHCA and 15% for patients with IHCA[12]. Similarly, a retrospective study in Qatar found higher survival-to-hospital discharge rates among IHCA patients (7.5%) compared to OHCA patients (2.4%)[9]. Furthermore, a prospective cohort study reported that survival with good neurological function remains persistently low, affecting only about one-fifth of cardiac arrest survivors regardless of the arrest setting (OHCA or IHCA) or assessment time point[13].

Within the Arab Asian population, many studies over the last two decades have examined OHCA or IHCA outcomes individually, compared them, and explored the associated demographic and predisposing survival factors. Although numerous systematic reviews have been conducted globally, there is a clear gap in high-quality, region-specific evidence. Moreover, no published systematic review has specifically compared the outcomes of OHCA and IHCA in this population. To address this critical knowledge gap, the present systematic review aimed to evaluate and compare survival rates, ROSC rates, survival-to-discharge rates, and neurological outcomes after OHCA and IHCA across the region. Additionally, we sought to contextualize these findings within the unique demographic composition (including the prevalence of expatriates) and the varied healthcare infrastructure of Arab Asian nations. By synthesizing evidence from regional studies, this review provides a foundation for developing targeted interventions, informing healthcare policies, and guiding future research to enhance cardiac arrest outcomes in the Arab Asian region.

MATERIALS AND METHODS

This systematic review was conducted according to the PRISMA statement (Figure 1).

Figure 1 PRISMA diagram showing the selection of included studies. IHCA: In-hospital cardiac arrest; OHCA: Out-of-hospital cardiac arrest.

Search strategy

A comprehensive literature search was conducted using PubMed, MEDLINE, EMBASE, and Google Scholar to identify relevant studies for this systematic review. The search utilized keywords including “IHCA”, “OHCA”, “cardiac arrest” “Middle East” “Arab” and “Asian” within the Title or Abstract fields. The medical subject headings (MeSH) terms used were “IHCA”[All Fields] AND “OHCA”[All Fields] AND (“heart arrest”[MeSH Terms] OR (“heart”[All Fields] AND “arrest”[All Fields]) OR “heart arrest”[All Fields] OR (“cardiac”[All Fields] AND “arrest”[All Fields]) OR “cardiac arrest”[All Fields]) AND (“Arabs”[MeSH Terms] OR “Arabs”[All Fields] OR “Arab”[All Fields]) AND (“Asian”[MeSH Terms] OR “Asian”[All Fields] OR “Asian people”[MeSH Terms]. In Embase, the studies were identified using country-specific search terms. For Google Scholar, advanced search filters (2000-2024) included combinations such as (“cardiac arrest” AND (“in-hospital” OR “out-of-hospital”) AND (“Arab” OR country names)). Manual reference checks of the bibliographies of the included studies and relevant reviews were performed.

Selection criteria

Studies were included if they were conducted in specific Arab Asian countries [Qatar, Lebanon, Kuwait, United Arab Emirates (UAE), Oman, Kingdom of Saudi Arabia (KSA), Bahrain, Iraq, Syria, Palestine, Yemen, and Jordan], published between 2000 and 2024, and involved adult cardiac arrest patients aged 18 years or older. Arab Asian countries refer to nations located in Asia that are part of the Arab world and are characterized by Arabic as an official language and a shared cultural-linguistic heritage. Both IHCA and OHCA studies, including those that directly compared the two settings, were eligible. For inclusion, studies were required to report at least one of the following outcomes: Mortality, ROSC, survival to hospital discharge (30-days/1-year), neurological outcomes, or deficits. Only full-text studies published in English were included. Full-text articles of eligible studies were reviewed for inclusion.

Studies were excluded if they were narrative reviews, not conducted in Arab Asian countries or not published in English, or if the full text was unavailable. Studies focusing exclusively on pediatric populations (< 18 years) or those that did not report any of the specified outcomes were also excluded.

Study selection and data extraction

Data extraction was conducted independently by three authors using a standardized form to ensure consistency and minimize the risk of error. Abstracts and full texts were reviewed based on predefined inclusion and exclusion criteria to determine the final study selection. Duplicate records were removed meticulously. All the extracted data were thoroughly reviewed for accuracy and completeness, and any disagreements among the authors were resolved through discussion and consensus. The key information was systematically collected from each eligible study. This included study characteristics such as author(s), year of publication, country of origin, and settings of cardiac arrest (IHCA or OHCA). The study design (cohort or observational) and sample size were recorded. Patient demographics including age, sex distribution, and reported comorbidities were extracted. In studies comparing resuscitation methods, the specific type of resuscitation (e.g., CPR, defibrillation) was recorded. Furthermore, the cause of cardiac arrest was noted when reported along with the type of initial cardiac rhythm (shockable vs non-shockable), if available. The main outcomes of interest were also extracted, including mortality rates, ROSC, survival to hospital discharge (30-day or 1-year), and reported neurological outcomes or deficits.

RESULTS

Study demographics and participant characteristics

This review included 44 observational studies from nine Arab Asian countries comprising 32535 participants. The sample sizes across the studies ranged from 20 to 4361. In all studies, the participants were predominantly male and aged between 40 to 60 years.

Study selection

The initial search yielded 168057 studies related to cardiac arrest (Figure 1). After applying keyword filters, 128994 studies were excluded, resulting in 39063 studies eligible for evaluation. Further exclusions were made for the following reasons: Irrelevant topics (n = 32049), studies conducted in countries outside the Arab Asian region (n = 5945), pediatric populations (n = 337), lack of outcome data (n = 265), unavailability of full text (n = 181), duplicate records (n = 128), narrative reviews (n = 86), studies published before 2000 (n = 24), and non-English language articles (n = 4). Consequently, 44 studies were included in the final analysis, comprising 27 studies on OHCA, 10 studies on IHCA, and seven studies comparing both IHCA and OHCA. Among the included OHCA studies the majority were from Qatar (8 studies), followed by Lebanon (4), Kuwait (4), UAE (4), Oman (3), KSA, Bahrain (1 each), one study having data for UAE and Lebanon and one multicenter Gulf Cooperation Council (GCC) study. Ten studies focused on IHCA, primarily from the KSA (4), UAE (4) and one study each from Lebanon and Iraq. The remaining seven studies compared OHCA and IHCA, originating from Qatar (4), the KSA (2), and Jordan (1) (Figure 2). No eligible studies in Yemen, Syria, or Palestine met the inclusion criteria.

Figure 2 Distribution of included studies based on the country. A: Out of hospital cardiac arrest; B: In-hospital cardiac arrest; C: Out of hospital cardiac arrest and in-hospital cardiac arrest. IHCA: In-hospital cardiac arrest; OHCA: Out-of-hospital cardiac arrest.

Figure 3 illustrates the annual number of studies published between 2014 and 2025. Despite covering publications from 2000 onward, no eligible studies preceded 2014. Over the study period, the publication frequency was lower in the initial years which increased peaked in 2019, and then decreased slightly to two in 2020. The number of publications rebounded to six in 2021, and 2022, and five in 2023 and 2024, respectively.

Figure 3  Frequency of studies based on the year of publication.

OHCA outcomes

Table 1 summarizes the outcomes of OHCA across the included Arab Asian countries, revealing variations in average mortality rates[14-40]. Kuwait reported the highest absolute mortality rate (99%)[28,29], followed by Bahrain (98.8%)[22] and Qatar (97.6%)[14]. In contrast, the KSA reported the lowest mortality rate (8.2%)[40]. Among the countries with average mortality data, Oman, Lebanon, Kuwait, and Qatar reported rates of 91.1%, 88.1%, 81.2%, and 77.4%, respectively. A multicenter GCC study reported an overall mortality rate of 43.3%[39]. However, the reported average ROSC rates differed significantly. Qatar had the highest rate (34.4%), followed by Oman (32.1%) and Lebanon (25.6%). Lower ROSC rates were reported in the UAE (9.7%) and Kuwait (3.3%). Bahrain reported an absolute ROSC rate of 18.1%. ROSC outcomes were not reported in studies from KSA or the multicenter GCC. Kuwait has the highest average survival rate (18.7%), followed by Qatar (17.5%), Oman (9.7%), and Lebanon (6.7%). Absolute survival-to-discharge rates were the highest in KSA (91.8%)[40] and GCC multicenter studies (56.6%)[39], while lower rates were reported for the UAE (4.2%)[36] and Bahrain (1.2%)[22].

Table 1 Out-of-hospital cardiac arrest outcomes in the Arab Asian studies, n (%)/mean ± SD/median (25^th-75^th percentiles).

Ref.	Type of study	Country	Population	Male:Female	Age	Cause of cardiac arrest	Type of initial rhythm	Type of CPR	Mortality	ROSC	STD 30 days or 1 year	Neurological outcome
Irfan et al[14], 2017	Retrospective	Qatar	n = 410	377:29	33 (27-46)	Motor vehicle collision 172 (42.0), pedestrian 119 (29.0), falls 57 (13.9), vulnerable road users 14 (3.4), others 48 (11.7)	Shockable: 12. Non-shockable: 17	Manual and mechanical chest compression device	400 (97.6)	61 (15.0)	10 (2.4)	NA
Irfan et al[15], 2016	Retrospective	Qatar	n = 447	360:87	51 (39-66)	Presumed cardiac etiology	Shockable: 88. Non-shockable: 350. Missing: 9	Manual and mechanical	411 (91.9)	103 (23.0)	36 (8.1)	Favorable cerebral performance: 24 (68.6)
Arabi et al[16], 2018	Retrospective	Qatar	n = 987	718:269	STEMI 53 ± 13. Without STEMI 58 ± 16	Presumed cardiac etiology	Shockable: 248	Not mentioned	590 (59.8)	NA	397 (40.2)	NA
Albizreh et al[17], 2021	Retrospective	Qatar	n = 1146	839:305	Group 1: ≤ 40 years. Group 2: > 40 years	Presumed cardiac etiology	≤ 40 years: Shockable 23/159. > 40 years: Shockable 183/985	Not mentioned	756 (65.9)	1146 (100.0)	≤ 40 years = 76 (47.8). > 40 years = 312 (31.7)	NA
Khazaal et al[18], 2022	Retrospective	Qatar	n = 987	718:269	Male: 55 ± 15. Female:61 ± 14	Presumed cardiac etiology	Not mentioned	Not mentioned	Females: 176 (65.4). Males: 414 (57.7)	NA	79 (8.0)	NA
Irfan et al[19], 2021	Retrospective	Qatar	n = 397	266:131	62.8 ± 17.5	Presumed cardiac etiology	Shockable: 49	Manual and mechanical chest compression device	371 (93.5)	40 (10.2)	26 (6.5)	NA
Awad et al[20], 2024	Retrospective	Qatar	n = 4306	3434:869	54.0 ± 17.9	Not mentioned	Shockable: 1110. Non-shockable: 3196	Manual	NA	1241 (28.8)	NA	NA
Awad et al[21], 2023	Retrospective	Qatar	n = 4283	3414:869	Males 52.7 ± 16.4. Females 62.2 ± 19.1	Not mentioned	Shockable: 1042. Non-shockable: 3241	Manual	NA	1256 (29.3)	NA	NA
Abuzeyad et al[22], 2024	Retrospective	Bahrain	n = 331	228:103	65 (49-78)	Presumed medical cause	Shockable: 28. Non-shockable: 303	Manual	327 (98.8)	60 (18.1)	4 (1.2)	0
Abou Dagher et al[23], 2021	Retrospective	Lebanon	n = 200	140:60	Bacteremia: 71.3 ± 16.9. Non-bacteremia: 70.1 ± 17.3	Not mentioned	Bacteremia: Shockable 12, non-shockable 77, missing 4. Non-bacteremia: Shockable 10, non-shockable 87, missing 10	Manual	Bacteremia: 80 (86.0). Non-bacteremia: 78 (72.9)	Bacteremia: 30 (32.3). Non-bacteremia: 50 (46.7)	Bacteremia: 0. Non-bacteremia: 3 (2.8)	Bacteremia: 93 bad outcome (100). Non-bacteremia: 105 bad outcome (98.1)
El Sayed et al[24], 2017	Retrospective	Lebanon	n = 271	179:92	69.93 ± 15.03	Not mentioned	Shockable: 28. Non-shockable: 243	Manual	258 (95.2)	NA	13 (4.8)	7 good neurological outcome (2.6)
Ong et al[25], 2022	Prospective	Lebanon	n = 225	152:73	75 (52.5-97.5)	Not mentioned	Shockable: 3. Non-shockable: 32	Manual	214 (95.1)	41 (18.2)	11 (4.9)	NA
El Sayed et al[26], 2014	Retrospective	Lebanon	n = 214	139:75	69 ± 15.4	Presumed cardiac etiology	Shockable: 23. Non-shockable: 190	Manual	203 (94.6)	39 (19.0)	11 (5.5)	5 good outcome (45.4)
Refaat et al[27], 2019	Retrospective	Lebanon	n = 54	40:15	17.9 ± 10.9	Cardiac 21, trauma 14, intoxication 5, congenital heart defect 7	Shockable: 12. Non-shockable: 42	Manual	41 (76)	NA	9 (16.7)	7 good outcomes (13)
Al Hasan et al[28], 2020	Retrospective	Kuwait	n = 286	192:94	61.1 ± 16	Presumed cardiac etiology	Shockable: 3. Non-shockable: 85	Manual	285 (99.7)	10 (3.5)	1 (0.3)	NA
Al Hasan et al[29], 2019	Pre and post intervention	Kuwait	n = 176	114:62	Pre-intervention 59 ± 17. Post-intervention 63 ± 16	Cardiovascular risk: Pre-intervention (22), post-intervention (21.9)	Not mentioned	Manual	175 (99.2)	Pre: 3 (6). Post: 2 (1.6)	Pre: 0 (0). Post: 1 (0.8)	7 good outcome (13)
Al Hasan et al[30], 2020	Retrospective	Kuwait	n = 140	122:18	39.9 ± 13.94	RTA 106, FFH 18, slip/fall 10, assault 6	Not mentioned	Not mentioned	40 (28)	4 (2.8)	100 (72)	NA
Hasan et al[31], 2019	Retrospective	Kuwait	n = 314	210:104	60.4	Presumed cardiac etiology	Shockable: 11. Non-shockable: 86	Manual	308 (98.09)	10 (3.18)	6 (1.91)	NA
Al-Habsi et al[32], 2024	Retrospective cross-sectional	Oman	n = 822	540:282	60.2 ± 17.6	Presumed medical etiology	Shockable: 41. Non-shockable: 781	Manual	773 (94)	178 (30.4)	49 (8.4)	NA
Nadar et al[33], 2018	Retrospective	Oman	n = 216	150:66	55 ± 17	Not mentioned	Shockable: 23. Non-shockable: 191. Heart blockage: 2	Manual	188 (87)	NA	28 (13)	NA
Maddali et al[34], 2023	Retrospective cross-sectional	Oman	n = 117	102:15	Median age 33	Presumed cardiac etiology	Shockable: 21. Non-shockable: 96	Manual	108 (92.3)	13 (11.11)	9 (7.69)	3 (2.5) neurological deficits
Alqahtani et al[35], 2019	Prospective	UAE	n = 715	548:167	50.6 (35-65)	Not mentioned	Shockable:79. Non-shockable: 604. Missing: 32	Manua and mechanical	NA	66 (9.2)	NA	NA
Alhmoudi et al[36], 2021	Prospective	UAE	n = 330	250:79	Not mentioned	Presumed cardiac etiology	Not mentioned	Mechanical	314 (95.1)	56 (17)	16 (5)	NA
Batt et al[37], 2016	Prospective	UAE	n = 384	291:93	50.9 ± 21.1	Presumed cardiac etiology	Shockable: 67. Non-shockable: 160. Unknown: 63	Manual and mechanical	NA	12 (3.1)	NA	NA
Ong et al[25], 2022	Prospective	UAE	n = 911	692:218	53 (37.5-68.5)	Not mentioned	Shockable: 128. Non-shockable: 725. Unknown: 56	Manual	NA	39 (4.3)	NA	NA
Alremeithi et al[38], 2022	Retrospective	UAE	n = 87	60:27	48 (range: 20-118)	Not mentioned	Shockable: 5. Non-shockable: 82	Not mentioned	84 (96.6)	13 (14.9)	3 (3.4)	1 (1.1) good outcome
Alsaeed et al[39], 2023	Retrospective	7 ACS registries in Gulf region (Bahrain, Kuwait, Oman, Qatar, KSA, UAE, Yemen)	n = 611	489:122	58 ± 14	Acute coronary syndrome	NA	Manual	265 (43.3)	NA	346 (56.6)	NA
Albinali et al[40], 2022	Quantitative cross-sectional	KSA	n = 257	184:73	48.4 ± 23.2	Presumed cardiac 144, Trauma 113	Not mentioned	Manual	21 (8.2)	NA	236 (91.8)	2 (22.2) good outcome

ROSC: Return of spontaneous circulation; STD: Survival to discharge; RTA: Road traffic accident; FFH: Fall from height; KSA: Kingdom of Saudi Arabia; UAE: United Arab Emirates; CRP: Cardiopulmonary resuscitation; NA: Not available.

Regarding neurological outcomes, an important measure of functional recovery, Qatar reported the highest absolute rate of good neurological outcomes (68.6%)[15], followed by KSA (22.2%)[40]. Lebanon reported an average good neurological outcome rate of 5%, whereas the UAE reported only 1.1%. Bahrain reported no good neurological outcomes, while Oman reported a poor neurological outcome rate of 2.5%[34]. Neurological outcome data were not available for Kuwait or the multicenter GCC study.

IHCA outcomes

A comparison of the IHCA outcomes across countries revealed significant variations (Table 2)[41-50]. Mortality rates averaged 73.6% in the UAE and 72.8% in KSA. In contrast, Lebanon and Iraq reported substantially higher rates (94.6% and 88%, respectively). Similarly, the ROSC rates also differed markedly: The UAE had an average ROSC rate of 51.3% compared with the KSA (35.3%), while Lebanon and Iraq reported ROSC rates of 55.9% and 12%, respectively. The reporting of neurological outcomes was inconsistent across studies. However, studies from the UAE indicated that an average of 41.1% of patients achieved favorable neurological recovery. Survival to discharge was also variable, with the UAE reporting average survival rates of 15.6% and 27.2% in KSA. In contrast, Iraq and Lebanon reported lower survival rates (12% and 5.4%, respectively).

Table 2 In-hospital cardiac arrest outcomes in the Arab Asian studies, n (%)/mean ± SD/median (25^th-75^th percentiles).

Ref.	Type of study	Country	Population	Male:Female	Age	Cause of cardiac arrest	Type of initial rhythm	Type of CPR	Mortality	ROSC	STD 30-days or 1 year	Neurological outcome
Eltarras et al[41], 2021	Retrospective	Lebanon	n = 680	466:214	68 ± 17	Not mentioned	Shockable: 63. Non-shockable: 617	Manual	643 (94.6)	380 (55.9)	37 (5.4)	NA
Alao et al[42], 2024	Retrospective	UAE	n = 366	244:122	70 (55-81)	Cardiac 89, respiratory 67, others 210	Shockable: 30. Non-shockable: 336	Not mentioned	335 (91.5)	159 (43.4)	31 (8.5)	20 (5.5) good neurological outcomes
Alao et al[43], 2022	Prospective	UAE	n = 447	279:147	Survived 62.5 (47.5-80.8). Died 70 (55-81)	Survived: Cardiac 15, respiratory 10, others 21. Died: Cardiac 90, respiratory 74, others 216	Shockable: Survived 15, died 18. Unshockable: Survived 31. Died 362	Not mentioned	399 (89.2)	171 (40)	48 (10.8)	264 (59) good neurological outcomes
Aziz et al[44], 2018	Retrospective	UAE	n = 685	454:231	57.3 ± 23.3	Not mentioned	Shockable: 61. Non-shockable: 624	Not mentioned	632 (92.3)	262 (38.2)	53 (7.7)	NA
Alhajri et al[45], 2021	Retrospective	UAE	n = 20	12:8	Median 60.5	Presumed cardiac etiology	Shockable: 1. Non-shockable: 19	Not mentioned	12 (60)	19 (95)	8 (40)	NA
Khdr et al[46], 2019	Prospective	Iraq	n = 100	47:53	63.65 ± 16.7	Unknown 58, thrombosis 15, electrolyte disturbances 5, hypoxia 8, hypovolemia 13, toxins 1	Shockable: 23. Non-shockable: 77	Manual	88 (88)	12 (12)	12 (12)	NA
Kaki et al[47], 2017	Retrospective	KSA	n = 4361	2414:1937	40 ± 31	Cardiac 1806, respiratory 906, both 1292	Shockable: 497. Non-shockable: 3864	Manual	3024 (70)	1766 (40.4)	1330 (30)	NA
Al Bshabshe et al[48], 2019	Retrospective	KSA	n = 700	414:286	59.1 ± 22.3	Respiratory 46, cardiac 654	Shockable: 26. Non-shockable: 674	Manual	442(63.1)	NA	258 (36.9)	NA
Rasheed et al[49], 2016	Retrospective	KSA	n = 1350	889:461	Adults 44.39 ± 0.46. Geriatrics 77.58 ± 0.41	Not mentioned	Shockable: 92. Non-shockable: 1225	Manual	Adults: 542 (69.5). Geriatrics: 396 (69.5)	NA	Adults 237 (30.5). Geriatrics 173 (30.5)	NA
Alhaj Zeen et al[50], 2023	Retrospective	KSA	n = 351	264:87	56.6 ± 14.7	Cardiac 212, non-cardiac 33, respiratory 45, trauma 17, unknown 44	Shockable 23. Non-shockable 328	Manual	311 (88.6)	106 (30.2)	40 (11.4)	NA

ROSC: Return of spontaneous circulation; STD: Survival to discharge; KSA: Kingdom of Saudi Arabia; UAE: United Arab Emirates; CRP: Cardiopulmonary resuscitation; NA: Not available.

Table 3 shows a comparative analysis of OHCA and IHCA outcomes across the selected studies[9,12,13,51-54]. In Qatar, four studies compared OHCA (n = 753) and IHCA (n = 545) outcomes[9,13,51,52]. However, none of these studies reported ROSC rates. The average mortality rate was slightly higher for OHCA (81.8%) than for IHCA (78.9%). The average survival-to-discharge rates were 18.2% (OHCA) and 21.2% (IHCA), whereas the average rate of favorable neurological outcomes was lower for OHCA (12%) than for IHCA (23%).

Table 3 Outcomes in studies comparing out of hospital cardiac arrest and in-hospital cardiac arrest in the Arab Asian studies, n (%)/mean ± SD/median (25^th-75^th percentiles).

Ref.	Type of study	Country	Population	Male:Female	Age	Cause of cardiac arrest	Type of initial rhythm	Type of CPR	Mortality	ROSC	STD 30 days or 1 year	Neurological outcome
Irfan et al[9], 2022	Retrospective	Qatar	OHCA (n = 410), IHCA (n = 199)	557:46	OHCA 33.0 (27-46). IHCA 33.5 (25-48.3)	OHCA, IHCA: Head injury (271, 120), spinal (28, 40), chest (40, 44), abdominal (67, 70)	OHCA Shockable: 12. IHCA Shockable: 15	Not mentioned	OHCA (n = 400, 97.6). IHCA (n = 184, 92.5)	NA	OHCA (n = 10, 2.4). IHCA (n = 15, 7.5)	NA
Elmelliti et al[51], 2023	Retrospective	Qatar	OHCA (n = 37), IHCA (n = 11)	36:12	41.88 ± 11.5	IHD 21, PE 6, others 21	Shockable: 16	Manual and ECPR	OHCA (n = 28, 75.7). IHCA (n = 10, 90.9)	NA	OHCA (n = 9, 24.3). IHCA (n = 1, 9.1)	NA
Shehatta et al[52], 2024	Retrospective	Qatar	OHCA (n = 25), IHCA (n = 62)	75:12	45.4 ± 11.9	Acute MI 52, Post cardiotomy 2, arrhythmia 3, HF 1, PE 7	Shockable: 27. Non-shockable: 61	Manual, ECPR, VA-ECMO	OHCA (n = 22, 88). IHCA (n = 43, 69.4)	NA	OHCA (n = 3, 12). IHCA (n = 19, 30.6)	Good neurological outcome for OHCA (n = 3, 12). IHCA (n = 19, 30.6)
Ait Hssain et al[13], 2025	Prospective	Qatar	OHCA (n = 281), IHCA (n = 273)	399:155	53.79 ± 16.24	Cardiac 383, non-cardiac 142, others 29	Shockable: 151	Manual	OHCA (n = 185, 65.8). IHCA (n = 171, 62.6)	NA	OHCA (n = 96, 34.2). IHCA (n = 102, 37.4)	Good neurological outcomes for OHCA (n = 36, 12.8), and IHCA (n = 42, 15.4)
Raffee et al[12], 2017	Retrospective	Jordan	OHCA (n = 79), IHCA (n = 257)	OHCA 51:28. IHCA 145:112	OHCA 59.50 ± 19.02. IHCA 63.36 ± 18.63	OHCA: IHD 3, MI 1, arrhythmia 1. IHCA: IHD 10, CHF 7, CVD 4, cancers 12	OHCA: Not mentioned. IHCA: Non-shockable 257	Manual	OHCA (n = 77, 97.03). IHCA (n = 219, 85.12)	NA	OHCA (n = 2, 2.97). IHCA (n = 38, 14.9)	NA
Alzahrani et al[53], 2019	Retrospective	KSA	OHCA (n = 15), IHCA (n = 414)	263:161	58.43 ± 18.02	Cardiac 88, non-cardiac 188, respiratory 102, sepsis 46	Shockable: 29. Non-shockable: 400	Not mentioned	OHCA (n = 9, 60.0). IHCA (n = 179, 43.2)	OHCA 8 (56.2). IHCA 235 (56.8)	NA	NA
Shirah et al[54], 2018	Retrospective	KSA	OHCA (n = 252), IHCA (n = 174)	287:139	64.0 ± 12.0	Not mentioned	OHCA Shockable: 0. Non-shockable: 252. IHCA Shockable: 52. Non-shockable: 120	Not mentioned	NA	NA	OHCA (n = 14, 5). IHCA (n = 52, 30)	NA

ROSC: Return of spontaneous circulation; STD: Survival to discharge; IHD: Ischemic heart disease; PE: Pulmonary embolism; MI: Myocardial infarction; CHF: Congestive heart failure; CVD: Cerebral vascular disease; IHCA: In-hospital cardiac arrest; OHCA: Out-of-hospital cardiac arrest; NA: Not available.

In Saudi Arabia (KSA), two studies included 267 OHCA patients and 588 IHCA patients[53,54]. Outcome reporting was inconsistent between the studies. The overall mortality rate was higher for OHCA (60.0%) than for IHCA (43.2%). The reported ROSC rates were 56.2% and 56.8% for OHCA and IHCA, respectively. Survival to hospital discharge was significantly lower for OHCA (5%) than for IHCA (30%). Neurological outcomes were not documented in either study.

A single study in Jordan[12], involving 79 OHCA patients and 257 IHCA patients, reported a higher mortality rate for OHCA (97.0%) than for IHCA (85.1%). The corresponding survival-to-discharge rates were 2.9% and 14.9% for OHCA and IHCA, respectively. This study did not report the ROSC or neurological outcomes.

DISCUSSION

This systematic review provides a critical evaluation of IHCA, OHCA, and comparative outcomes across Arab Asian countries, presenting a comprehensive synthesis of 24 years of regional data. The findings revealed significant variations in survival rates, neurological recovery, and ROSC across countries, and between IHCA and OHCA cases. While these trends are consistent with global patterns, they also expose unique region-specific challenges, including critical knowledge gaps and the lack of standardized reporting practices across nations. This synthesis is particularly important given the lack of comprehensive regional reviews and the distinctive demographic and healthcare contexts of Arab Asian countries. Our analysis found that Qatar, the UAE, and Saudi Arabia contributed the largest number of studies on cardiac arrest, reflecting their growing investments in healthcare research. In contrast, Iraq, Jordan, and Bahrain had fewer studies, and no eligible studies from Yemen, Syria, or Palestine met the inclusion criteria. Sociopolitical factors also affect healthcare delivery. In Yemen, longstanding healthcare system weaknesses have been further exacerbated by ongoing conflict, leading to a fragmented and largely ineffective health infrastructure[55]. Similarly, the civil war in Syria severely disrupted healthcare delivery and research capacity[56]. Although health-related publications have increased during the conflict period, much of this work consists of commentaries and editorials rather than original research, resulting in significant gaps in the scientific literature[57,58]. In Palestine, political instability, resource limitations, and movement restrictions have further hindered emergency medical services (EMS) and severely constrained the ability to conduct clinical research or collect reliable data on critical conditions, such as cardiac arrest[59].

Our analysis revealed that IHCA generally demonstrated more favorable outcomes than OHCA. Across the included studies, survival to hospital discharge averaged 21.2% for IHCA vs 18.2% for OHCA, and favorable neurological recovery was higher in IHCA (23%) than in OHCA (12%). These findings are consistent with international literature, where IHCA patients benefit from immediate medical intervention and structured resuscitation protocols[11,60]. Notably, hospitals are equipped with trained healthcare personnel, advanced life support systems, and post-resuscitation care pathways, all of which contribute to superior outcomes[61]. Moreover, a rapid response, structured CPR training, and access to targeted temperature management (TTM) for IHCA patients enhance neurological recovery and survival post resuscitation[62,63].

Our findings revealed considerable variability in cardiac arrest mortality and survival rates across regions. The outcomes of OHCA in Arab-Asian countries remain consistently poor, with mortality rates exceeding 80% in most settings. This underscores a critical need for improved interventions to enhance patient survival rates. For instance, Kuwait reported a high OHCA mortality rate of 99%[28,29], whereas Bahrain[22] and Qatar[14] reported rates of 98.8% and 97.6%, respectively. Although Saudi Arabia (KSA) reported a comparatively lower OHCA mortality rate, this observation is based only on a single cross-sectional study[40]. KSA also demonstrated better IHCA outcomes with lower mortality rates than other countries in the region. Similarly, the UAE reported relatively better survival rates, likely reflecting investment in EMS systems and public health initiatives. Notably, studies from Qatar showed an average OHCA mortality rate of 81.8% compared with 78.9% for IHCA, indicating a minimal difference within this specific context. In contrast, Lebanon reported the highest IHCA mortality at 94.6%[41], highlighting the significant disparities and the pressing need for targeted healthcare improvements. Notably, OHCA survival rates cross the Arab Asian countries ranged widely from 1.2% to 40.2%. In comparison, a 6.4% OHCA survival rate was reported from high-income countries in the Asia-Pacific region[64] suggesting systemic gaps in prehospital care. An earlier meta-analysis of mostly European and American studies found OHCA survival to hospital admission was 22.0%, survival to discharge was 8.8%, with 1-month and 1-year survival rates of 10.7% and 7.7%, respectively[65]. This wide variation in OHCA survival rates may be attributed to differences in the prehospital emergency response systems, low bystander CPR rates, limited availability of automated external defibrillators (AEDs), and access to advanced post-resuscitation care. Delayed response times and inadequate public awareness campaigns further impact outcomes[66,67]. Moreover, differences in study methodologies and reporting may also contribute to the observed variability. Implementing comprehensive public health strategies and expanding community CPR training[68] could improve OHCA survival in the region.

This review also highlights the variability in ROSC rates among countries. Qatar achieved the highest OHCA ROSC rate (34.4%), while Kuwait reported a rate of only 3.3%. This disparity reflects heterogeneity in EMS efficiency, access to prehospital interventions, and the quality of resuscitation efforts[69]. In contrast, IHCA ROSC rates were generally higher and more consistent, with the UAE reporting an average rate of 51.3%, demonstrating the relative effectiveness of in-hospital resuscitation protocols[44].

Neurological outcomes remain critical indicators of the quality of postcardiac arrest care. Data from Qatar showed that 68.6% of OHCA survivors achieved favorable neurological recovery[15], whereas a single study from Bahrain reported no cases with good neurological outcomes[22]. These findings underline the importance of post-resuscitation care in neurocritical care units, rehabilitation services, and TTM application[63]. The variability across countries emphasizes the need for standardized post-arrest care protocols and investment in specialized care units. The demographic composition of the region, characterized by large expatriate populations in countries such as Qatar and the UAE, presents additional challenges. These transient populations often lack access to health education programs and may be underrepresented in health interventions, complicating efforts to improve community responses to cardiac arrests[70]. Comparisons with Western countries revealed further disparities. Initiatives such as widespread AED deployment, school-based CPR training, and integrated EMS systems in countries such as Denmark and Japan have drastically improved OHCA survival rates[71,72]. In Japan, 1-month survival with minimal neurological impairment increased from 10.6% to 19.2%, coinciding with a rise in public-access AED use from 1.2% to 6.2% between 2005 and 2007[71]. Similarly, Denmark reported more than a threefold increase in 30-day survival (from 3.5% to 10.8%) and a doubling of bystander CPR rates (from 21.1% to 44.9%) over the period 2001 to 2010, with bystander CPR demonstrating a strong association with improved survival[72]. In contrast, despite showing gradual progress in EMS development, Arab Asian countries have lagged in implementing these lifesaving measures at the community level. Notably, Qatar, the UAE, and Saudi Arabia contributed to most of the studies included in this review, reflecting their relatively advanced healthcare systems and growing investments in emergency care research.

The fluctuating number of studies from this region over the years, with a marked decline in 2020, is likely attributable to the coronavirus disease 2019 (COVID-19) pandemic, which disrupted healthcare systems and research activities globally. Interestingly, subsequent years saw renewed interest in cardiac arrest research, possibly owing to heightened awareness of the cardiac complications associated with COVID-19[73].

Limitations

This study had several limitations that must be acknowledged. First, most of the included studies were observational in design and varied in methodological rigor, which may have introduced bias and limited the generalizability of the findings. Quality assessment was not performed because all the studies were retrospective. Furthermore, the reliance on retrospective studies may limit the ability to establish causal relationships between specific interventions and patient outcomes. Second, a meta-analysis was not conducted, limiting the ability to quantitatively synthesize data across the included studies. This would limit the ability to determine the overall effect sizes and might be subject to interpretation bias. Third, significant heterogeneity exists in the definitions of outcomes, such as ROSC and neurological recovery, across studies, complicating direct comparisons. Fourth, underreporting of key variables such as the time to first CPR, initial cardiac rhythm, and post-resuscitation care practices restricts the ability to identify specific predictors of survival. Fifth, data from several Arab Asian countries, including Yemen, Syria, and Palestine, were lacking, creating a potential geographic bias. Finally, the language restriction to English publications may have excluded relevant studies.

Despite these limitations, a major strength of this systematic review is that it incorporated all available studies conducted in Arab Asian countries, offering a comprehensive analysis of cardiac arrest outcomes in this region. The PAROS trial[74], while valuable, included only one study each concerning OHCA in the UAE and Lebanon, resulting in limited regional representation. By synthesizing data from Arab Asian countries, this review provides a broader and more accurate depiction of cardiac arrest outcomes.

CONCLUSION

This systematic review highlights the clear disparity in survival outcomes between IHCA and OHCA in Arab-Asian countries, with IHCA demonstrating better survival and neurological outcomes. Despite progress in some countries, the outcomes remain suboptimal compared with international standards. Improving community preparedness through CPR and AED training, strengthening the EMS infrastructure, and standardizing post-arrest care protocols are vital steps toward improving survival rates. Future multicenter studies with standardized methodologies are required to provide high-quality evidence and inform region-specific interventions for cardiac arrest management.