My blood pressure has been 140/90 for two years. Had a lot of test and it will not go down with medication could this be affecting my airway when I sleep?

It has to go down. At 42 , BP of 140/90 is not normal ,now great medications are available , there nothing like ' it will not go down ' It has to to , prevent complication from hypertension . Avoid salt , do regular exercises , reduce weight if it is a problem , you air way problem could be due to this not B P . Speak to your doctor may switch medications.