Sleep, snoring, apnoea: who has been tested?

Many attacks come at night. Studies found apnoea (breathing pauses in sleep) in a third to almost half of patients, but a link to attacks is not proven. Whether a CPAP mask helps is being tested. Have you had a sleep study? What was found, and did treating apnoea help night attacks? Sources: https://headachemedicine.com.br/index.php/hm/article/view/654 https://clinicaltrials.gov/study/NCT03397563