I Am 69 YO Male With OSA And BPH, Frequently

I am 69 YO male with OSA and BPH, frequently feeling cold especially in evening, while my 62 YO wife and 85 YO mother in law feel fine. I walk around the house in a robe most of the time. I have a persistent cough, made better with antihistamines and musinex. Once I recently tested borderline for asthma (score 19, 20 needed for diagnosis). I would say I have low energy or chronic fatigue. I sleep 8-10 hours at night and 2 hours nap daily. I have had thyroid tests in past two years, one showed low and one was in normal range. I plan to see my doctor next week and was wondering whether thyroid conditions can be intermittent, and whether they could be source of my problems.