This report presents an analysis of factors associated with decreased CD4 counts in HIV-positive patients across 25 states in Nigeria. The study employs statistical methods, including descriptive statistics, bivariate analysis, chi-square tests, and multinomial logistic regression using SPSS, to examine the influence of socio-demographic, baseline, and treatment factors. Independent variables such as age, gender, baseline CD4 count, weight, WHO clinical stage, geographical location, and ART switch are analyzed against the dependent variable of decreased CD4 count. The analysis reveals significant associations between age, baseline CD4 count, base weight, WHO stage, and geographical location with changes in CD4 counts, while gender showed no significant association. The findings provide insights into the patient demographics and treatment factors impacting CD4 counts, contributing to a better understanding of HIV progression and management within the Nigerian context.