I went to get a sleep study and my respiratory effort related arousal were high but ny ahi was 1 but was still was diagnosed with osa. please explain.?

RDI was high: Rera is factored into a number called the rdi (respiratory disturbance index). Ahi is the apnea-hypopnea index, meaning you stopped breathing or had a 50% reduction in airflow with desaturation(drop in oxygen) an average 1 time per hour. When rera is added, you get a rdi score and this was elevated. Rera's are events where there is resistance to airflow but not enough to call apnea or hypopnea.

Arousals affect : The arousals will disrupt your sleep cycle when having difficulty breathing during your sleep, even if they dont "wake" you up.

R/O OSA: OSA can be suggested by history and physical. Excess snoring/daytime sleepiness/apneic episodes/ aM headaches. And the Exam obesity/small oral airway/collar size>18. The definitive test is a PSG with split night/CPAP titration. I would request copy of sleep study and get a second opinion if you are not satisfied with the options. You are young CPAP can be difficult to tolerate. ENT FOR UPP EVAL.