Throat,nose infections, high degree of mucus from nose and throat. no, not using BPAP/CPAP , taking antibiotic courses - 6-7 a year like Euthromycin,Cipro, Amoxi. Sinus allergy tablets,cough syrup, tired and fatigue. Feeling tired even on small work like brooming ,, stepping on stairs, mucus is quite sticky and solid type. my IgM ,is low for last 3-4 years. I am 56, catching such infections since birth as far as I remember.
What kind of infections? If it's sinus or breathing related (lungs, ex: coughing, sinus drainage), and you are using a CPAP/BiPAP machine then yes, it can be related if your not keeping your equipment clean. it can also cause headaches/migraines.
Not a symptom/effect of OSA - I suffer from minor OSA myself.
The symptoms are well documented and easy to find so I'll not try to summarize them here. If the "subject" has none of those symptoms I'd guess no OSA.