The relation of Interleukin18 (IL18) gene polymorphisms and Mild Cognitive Impairment and their impact on physical outcomes in elderly
Background: Mild Cognitive Impairment (MCI) is an important medical problem in elderly which may progress to dementia. Early recognition and intervention are important to prevent dementia harmful consequences. Its prevalence in Egyptian governorates ranges from1.7% to 39.3%. Frailty is an important geriatric giant that increase probability of disabilities and diseases. Both cognitive impairment and frailty are thought to be related to each other. Co-presence of MCI and physical frailty yield cognitive frailty which considered cumulative risk for disabilities. Inflammation plays a vital role in cognitive impairment and thought to mediate frailty in elderly population.
Objective: In our study we investigated the relationship between Interleukin-18 gene polymorphisms at 607 C/A and 137 C/G and MCI and physical frailty.
Methods: 90 elderly patients were assessed for cognitive status by Arabic version of Montreal Cognitive Assessment tool (MoCA) and presence of physical frailty. Participants were categorized into Group I: patients with both MCI and physical frailty or prefrailty (Cognitive frailty), Group II: patients with MCI without physical frailty or prefrailty, and Group III: Participants with normal cognition. Genotyping of interleukin-18 gene polymorphism by sequence-specific PCR were done for all patients.
Results: CC genotype at position 607 C/A is associated with lower MoCA score and higher physical frailty score than other genotypes (p= <0.001 and 0.013) respectively, while GG genotype at position 137 C/G is associated with lower MoCA score (P <0.001) and this remained significant after adjustment of confounding factors (OR: 44.990, 95% CI:(1.498 – 1351.44), p=0.028, with no substantial relation to physical frailty (P=0.545) respectively.
Conclusion: Interleukin- 18 gene polymorphisms play an important role in mild cognitive impairment. However, their role in physical frailty is still questionable.