Table 3. Hyperuricemia and its association with ischemic stroke.

SD, standard deviation; SUA, serum uric acid; N/A, not available; NIDDM, non-insulin-dependent diabetes mellitus; CHD, coronary heart disease; MI, myocardial infarction; AIS, Acute Ischemic Stroke

Referenced Trial	Sample Size	Study Participants	Mean Uric acid Levels	Primary Outcomes	Objective	Conclusion
Mehrpour et al. (2012) Tehran, Iran [55]	55	46 – Ischemic stroke 9 – Hemorrhagic stroke	5.94 mg/dL (SD 1.70)	26 (47.3%) patients had hyperuricemia	To determine the SUA levels in acute stroke patients	The prevalence of hyperuricemia in acute stroke patients was significantly higher than normal population
Milionis et al. (2005) Greece [56]	329	163 – Ischemic stroke 166 - controls	5.6 ± 1.7 mg/dL vs. 4.8 ± 1.4 mg/dL (stroke patients vs control respectively)	49 (30.1%) stroke patients had hyperuricemia	To assess the association between SUA and acute ischemic/nonembolic stroke	Elevated SUA was associated with increased risk for acute ischemic/nonembolic stroke in elderly patients
Takagi (1982) Japan [57]	314	314 men from village of Ushibuka (30 resulted in AIS)	6.9 ± 2.0 mg/dL vs. 5.8 ± 1.8           mg/dL (stroke vs no stroke respectively)	High SUA levels were found in patients who experienced a stroke	To clarify the risk factors for stroke from an epidemiological point of view	SUA levels showed a positive correlation to the incidence of AIS
Lehto et al. (1998) Finland [58]	1,017	551 men and 466 women with NIDDM (114 participants had a fatal/non-fatal stroke)	N/A	Elevated SUA level (>295 umol/L) is significantly associated with AIS	To investigate SUA as an independent risk factor of stroke in NIDDM patients without nephropathy	Hyperuricemia is a strong indicator of stroke events in NIDDM patients
Chien et al. (2005) Taiwan [59]	3,602	1,703 men and 1,899 women (155 participants resulted in AIS)	5.67 mg/dL (SD 1.68) vs 6.91 mg/dL (SD 2.95); baseline vs fifth followup (8 year) respectively	As uric acid increased one unit, men had 1.24 times and women had 1.60 times higher risk for stroke events	To investigate the association of SUA levels in CHD and AIS	Hyperuricemia is associated with increased stroke events
The Rotterdam Study (2006) Netherlands [9]	4,385	Out of total, 381 participants experienced AIS	Baseline is 309 umol/L with a hazard ratio of 1.77 (1.10-2.83) for ischemic stroke and 1.68 (0.68-4.15) for hemorrhagic stroke	High SUA levels were associated with the right of MI and AIS	To investigate the association between SUA and CHD and stroke	SUA is a strong risk factor for MI and stroke
The ARIC Study (2006) USA [60]	13,413	Out of total, 381 participants experienced AIS	5.97 ± 1.52 mg/dL with 24.1% of participant having uric acid >6.9 mg/dL	A positive moderate association between SUA and AIS was noted	To investigate the relation between SUA and AIS	SUA is an independent indicator of ischemic stroke among patients who are not using diuretics
Khalil et al. (2020) Bangladesh [61]	388	169 cases (AIS) and 169 controls	6.03 ± 1.84 mg/dL vs. 4.34 ± 1.60 mg/dL (cases vs control respectively	31% of cases had hyperuricemia; For every one-unit increase in SUA level, the rate of having an ischemic stroke was increased by 25%	To examine the relation between SUA level and ischemic stroke; also assessed gender-based differences	SUA is considerably associated with acute phase of ischemic stroke; gender-based analysis exhibits this in females only.
Irfan et al. (2020) Pakistan [17]	148	74 cases (AIS) and 74 controls	5.94 ± 1.70 mg/dL	48.6% of participants in the case group had hyperuricemia and ischemic stroke	To determine the connection between hyperuricemia and AIS	The prevalence of hyperuricemia in patients with AIS was higher compared to the healthy population
Tu et al. (2019) Shanghai [36]	3243	1784 males and 1459 females; 268 participants had a stroke	5.6 ± 1.6 mg/dL vs 8.3 ± 1.5 mg/dL (Baseline vs hyperuricemic)	Hyperuricemic subjects had a higher cumulative incidence of ischemic and hemorrhagic stroke	To evaluate whether asymptomatic hyperuricemia is associated with an increased risk of stroke in elderly subjects without comorbidities	Asymptomatic hyperuricemia without comorbidities had a higher (2.32 fold) risk of incident stroke