What are you doing to treat the CRF? Fluid therapy? Phosphorus binders? Calcium supplements? Potassium supplements? Probiotics? Transfer Factors? ACE inhibitor?
The increase in sleeping, lack of energy, lack of appetite, weight loss, looking and feeling miserable can also be attributed to untreated CRF.
Do you have the most recent bloodtest results? When were the last tests done? Can you post the BUN/Urea, Creatinine, phosphorus, potassium, calcium, and any other abnormal value. What is the USG (urine specific gravity)?
What are you feeding? and what have you tried in the way of appetite stimulation?
A very valuable resource site about CRF http://www.felinecrf.org/index.htm
From the same person as the CRF link one for arthritis http://www.harpsie.com/arthritis.htm
My 18yr old cat was diagnosed with azotemia/early stage CRF 2 years ago her thread is here http://www.pets.ca/forum/showthread.php?t=45017