5. Sleep disturbances could be salient issues among older adults. Your father, age 63, has retired from his 40 years work life since last year. You often noticed your father dozing off during the day despite he appeared to have slept through all night without waking up during the night. Your mother complained also of his loud snoring during asleep. You suspect your father has sleep problem and persuading your father to seek medical consultation. Which of the following(s) may have contributed to the sleep problem of this old gentleman? *