Whole-exome sequencing analyses in a Saudi Ischemic Stroke Cohort reveal association signals, and shows polygenic risk scores are related to Modified Rankin Scale Risk.

Ischemic stroke represents a significant societal burden across the globe. Rare high penetrant monogenic variants and less pathogenic common single nucleotide polymorphisms (SNPs) have been described as being associated with risk of diseases. Genetic studies in Saudi Arabian patients offer a greater opportunity to detect rare high penetrant mutations enriched in these consanguineous populations. We performed whole exome sequencing on 387 ischemic stroke subjects from Saudi Arabian hospital networks with up to 20,230 controls from the Saudi Human Genome Project and performed gene burden analyses of variants in 177 a priori loci derived from knowledge-driven curation of monogenic and genome-wide association studies of stroke. Using gene-burden analyses, we observed significant associations in numerous loci under autosomal dominant and/or recessive modelling. Stroke subjects with modified Rankin Scale (mRSs) above 3 were found to carry greater cumulative polygenic risk score (PRS) from rare variants in stroke genes (standardized PRS mean > 0) compared to the population average (standardized PRS mean = 0). However, patients with mRS of 3 or lower had lower cumulative genetic risk from rare variants in stroke genes (OR (95%CI) = 1.79 (1.29-2.49), p = 0.0005), with the means of standardized PRS at or lower than 0. In conclusion, gene burden testing in Saudi stroke populations reveals a number of statistically significant signals under different disease inheritance models. However, interestingly, stroke subjects with mRS of 3 or lower had lower cumulative genetic risk from rare variants in stroke genes and therefore, determining the potential mRS cutoffs to use for clinical significance may allow risk stratification of this population.

Electrophysiologic severity of carpal tunnel syndrome in diabetic patients of the Saudi population.

OBJECTIVE: To study the frequency of multiple vascular risk factors and electrophysiological severity of carpal tunnel syndrome (CTS) in Saudi diabetic patients. METHODS: This retrospective cross-sectional study was conducted in Neurology Department, King Fahd Hospital of University, Al-Khobar, Kingdom of Saudi Arabia from April 2017 to March 2018 and included 200 patients with CTS. Body parameters, such as blood pressure (BP), weight, height, and body mass index (BMI), along with laboratory and median nerve electrophysiological parameters, of diabetic and non-diabetic patients were compared, and a p-value<0.05 was considered significant. RESULTS: Frequency of hypertension (HTN) and obesity was significantly higher in diabetic patients (p<0.05). Mean median nerve sensory amplitude (MNSA) was lower in diabetic patients (p<0.05).Non-recordable nerves, as well as bilateral and extremely severe CTS (p<0.05), were more frequently seen in diabetic patients. Age, BMI, systolic BP, low serum high density lipoprotein (HDL), high triglycerides, high fasting blood sugar, and high glycated hemoglobin (Hba1c) levels, known to affect the electrophysiological severity of CTS, had a statistically significant association with diabetes. CONCLUSION: Diabetes mellitus (DM) and obesity are the most commonly identified risk factors of CTS. Dyslipidemia, HTN and obesity are more frequently seen in diabetic patients with CTS. These concurrent risk factors are confounding the electrophysiological severity of CTS in these patients. Further larger-scale studies with the control of confounding factors are recommended.

Epidemiological study of epilepsy from a tertiary care hospital in kingdom of Saudi Arabia.

OBJECTIVE: To identify the types of seizures and describe the clinical features, EEG and radiological findings among patients with epilepsy. METHODS: In this retrospective epidemiological study, we analyzed the medical records of the patients with the diagnosis of epilepsy during the study period (January 1st 2016- December 2016) RESULTS: The study included 184 patients, 91 (49.5%) were males and 93 (50.5%) females. Age ranged between 12 and 85 years (mean 35.4+/-19.5 SD years). Most of the patients 150 (82%) had Generalized tonic clonic seizures followed by focal onset in 27 (14%) of the patients. Main EEG abnormality was focal to bilateral was recorded in 53 (41%), idiopathic/ cryptogenic epilepsy was diagnosed in 61% of the patients. The most common abnormalities on brain imaging were temporal/hippocampal atrophy/stroke. The most common cause of symptomatic epilepsy was stroke found in 20(11%) followed by post infectious epilepsy and head trauma. CONCLUSION: Seizure types, EEG characteristics and etiologies of symptomatic epilepsy in our cohort of patients are in accordance with the current literature. Slight discrepancy observed in gender distribution and etiologies for symptomatic epilepsy compared with other studies from Saudi Arabia need to be studied further by prospective and population base studies.