Osteoarthritis (OA), a chronic degenerative disease, is often reported in middle-aged and elderly people. Knee OA is the most common type of OA and also a major reason for disability. OA pain is described as a mixed type of pain entangling both nociceptive and neuropathic components. 

Knee OA pain is believed to arise due to central sensitization. This process may also generate comorbid conditions like fear, anxiety, depression, and sleep disorders. 

A recent study thus investigated the effects of duloxetine and pregabalin predominantly on pain and functional status in patients with knee osteoarthritis and secondarily on quality of life, depression, anxiety, and sleep disturbance.

66 patients diagnosed with knee osteoarthritis were included and randomized to use either duloxetine or pregabalin. They were then evaluated by Visual Analog Scale, Neuropathic Pain Diagnostic Questionnaire, Western Ontario and McMaster University Osteoarthritis Index, Short Form-36, Beck Depression Inventory, Beck Anxiety Inventory, and Pittsburg Sleep Quality Index at baseline and after 4 and 12 weeks of treatment.

Improvements were seen in the Visual Analog Scale, Neuropathic Pain Diagnostic Questionnaire, Western Ontario and McMaster University Osteoarthritis Index, Short Form-36 (except the mental health subgroup scores in the duloxetine-treated group), Beck Depression Inventory, and Beck Anxiety Inventory scores in both groups after 4 weeks of treatment. Pittsburg Sleep Quality Index total scores and SF-36 mental health subgroup scores began to improve on the 4th and 12th weeks in pregabalin- and duloxetine-treated groups, respectively.

Thus, the results proved that using centrally acting drugs, to control pain and associated symptoms, can increase the likelihood of treatment success.

Source: Rev. Assoc. Med. Bras. 2022;68 (3). https://doi.org/10.1590/1806-9282.20211047