Prevalence and patterns of abnormal urinalysis findings among undergraduate students in a screening context

Background: Urinalysis is widely used as a simple and inexpensive screening tool. However, the overall prevalence of "abnormal" findings in asymptomatic populations may be difficult to interpret when clinically relevant findings are combined with nonspecific changes in urine concentration or appearance. Objectives: To determine the prevalence and patterns of abnormal urinalysis findings among undergraduate students, distinguish clinical findings from those related to urine concentration and appearance, and examine their associations with water and beverage consumption and urinary health awareness. Materials and methods: This cross-sectional study included 336 undergraduate students. A single midstream spot urine specimen was collected from each participant and evaluated by physical, chemical, and microscopic examination. The primary outcome was the presence of at least one abnormal urinalysis finding according to prespecified criteria. Clinical findings were summarized separately from findings related to urine concentration and appearance. Associations with plain water intake, beverage consumption, and urinary health awareness were examined using Poisson regression with robust variance estimation, with adjustment for age and gender. Results: Overall, 58.0% of participants had at least one abnormal urinalysis finding. However, most findings involved urine concentration or appearance (53.3%), whereas clinical findings were observed in only 14.6%. High urinary health awareness was associated with a higher prevalence of the composite urinalysis outcome (adjusted prevalence ratio 1.32; 95% confidence interval 1.04-1.68). Consumption of more than seven glasses of milk-added brewed beverages per week was also associated with the composite outcome, whereas plain water intake and other beverage categories were not significantly associated. Conclusion: The high overall prevalence of abnormal urinalysis findings was driven mainly by findings related to urine concentration and appearance rather than by clinical findings. Reporting only the composite prevalence may therefore suggest a greater burden of clinically relevant abnormalities than was actually observed. Separating clinical findings from those related to urine concentration or appearance provides a clearer and more appropriate framework for interpreting screening urinalysis.