Evaluation of Oxidative Stress Indicators, Specifically 8-Hydroxydeoxyguanosine and Malondialdehyde, alongside Total Antioxidant Capacity in Patients with Chronic Renal Disease who are Tobacco Smokers: Case-Control Study.

BACKGROUND

Smoking and other lifestyle-related risk factors, as well as oxidative stress, frequently make chronic kidney disease (CKD) worse. Through the usage of a matched case-control design, this research sought to observe the correlation between tobacco use and oxidative stress biomarkers in patients with CKD.

AIM: To evaluate the oxidative stress markers 8-hydroxydeoxyguanosine and malondialdehyde, and total antioxidant capacity in tobacco smoker's chronic renal disease patients and shed light on the biological effects of smoking in CKD patients with emphasise the significance of quitting smoking as part of CKD care by detecting and measuring these biochemical variations.

METHODOLOGY: Al-Azhar University Hospitals carried out a six-month case-control study from January to June 2025. A total of sixty people between the ages of 25 and 70 were recruited and split into two age- and sex-matched groups: 30 healthy non-smokers made up Group I, and 30 tobacco smokers with a clinically confirmed CKD made up Group II. After determining that the data were normal using the Shapiro-Wilk test, key biomarkers, including malondialdehyde (MDA), cotinine, total antioxidant capacity (TAC), creatinine, glomerular filteration rate (GFR) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), were quantified and statistically examined using both parametric and non-parametric tests.

RESULTS

The average age of smokers with CKD was 42.33 ± 9.21 years, whereas the average age of non-smokers was 41.33 ± 9.46 years. The age difference between the groups was not statistically significant (t(58) = -0.47, p = 0.64), according to an independent samples t-test assuming equal variances, suggesting that the groups were suitably age-matched. Moreover, different distributional patterns were obtained through a boxplot that contrasted the five biomarkers, creatinine, malondialdehyde, cotinine, TAC, and 8-OHdG, between smokers with CKD and non-smokers. The results indicate that smokers with CKD had significantly higher levels of 8-OHdG and cotinine, suggesting greater oxidative DNA damage and nicotine exposure in this population. Smokers with CKD had significantly decreased TAC, which may indicate weakened antioxidant defences. Because of increased lipid peroxidation and oxidative stress, the smoker group had greater amounts of malondialdehyde, with a wider spread and a higher median. With a higher median and the presence of extreme values, creatinine levels were also significantly higher among CKD smokers, which is consistent with decreased kidney function in this population. With every factor considered, the boxplots graphically support the statistical conclusions by emphasising the relation between tobacco use and increased oxidative stress, renal dysfunction, and decreased antioxidant capacity among individuals with CKD.

CONCLUSION

Tobacco-Smoking Patients with Chronic Kidney Disease have exacerbated oxidative stress, and decreased systemic antioxidant capacity. Numerous biomarkers exhibit consistent statistical and graphical trends, which highlight the biological influence of smoking on the progression of CKD.