My typically pleasant 76 year old male was livid when I walked into the exam room. He was pacing back and forth with furrowed eyebrows. I gingerly inquired what was bothering him the most. He answered that he was upset with another patient in the waiting room who was trying to compare her intake form with his intake form. On the intake forms, we ask patients to mark their pain score, fill out their review of systems, and check the health assessment questionnaire. He exclaimed that she marked that she had a pain score of 10, and he knows that she does not have a pain score of 10 since she is sitting and talking to him. He wanted to alert me that the patient in the waiting room was lying on her forms! I listened to him and told him that I will take it into consideration when I see her. This exuberant reaction from my patient made me think about how superficial our scores are.
How can we objectively measure pain when it is subjective complaint? What one person’s perception of pain is so different from another person’s experience. I performed a Google search on tools to quantify pain – there are at least 10 pain scales commonly used in clinical practice, and these can be classified into one of three categories:
1. Numerical rating scales (NRS) use numbers to rate pain.
2. Visual analog scales (VAS) typically ask a patient to mark a place on a scale that aligns with their level of pain.
3. Categorical scales use words as the primary communication tool and may also incorporate numbers, colors, or relative location to communicate pain.
So you can see why my patient was so upset; he was accustomed to using categorical pain scales with precise descriptions such that a pain score of 10 is when you have to be taking to the emergency room. My other patient, however, saw nothing wrong with what she marked as she had based her pain rating on her own life experiences with fibromyalgia being the most pain she ever had as it had kept her from enjoying her family and doing her usual activities. Most patients cannot separate factors as stress, depression, or fatigue from pain.
During my residency, the attending would ask a patient what his/her pain level was and if the patient says, “I don’t know” then my attending will prompt the patient by asking the patient to compare their current pain with giving birth. What misogynistic thinking! What if she never had a baby? What if she used an epidural? I had preferred to give my patient a different visual for comparison--imagine it is a very cold day and 3 cans of corn drops from the top shelf of your cabinet onto your toe; the pain that you feel when the cans strikes your toe is a level 10.
Reliable and accurate measurements of pain are essential for gauging effectiveness of therapy both in clinical practice and in research trials. How many drug studies have failed because their primary endpoint of pain reduction has not been met? Some physicians interchangeably use patient pain score and patient global score; this is also inaccurate and can be misleading. We want medications that would treat inflammation and halt disease progression, but the hallmark of inflammation is dolor, calor and rubor. What if calor and rubor are absent but dolor is screaming? Is the disease still active? How can we incorporate pain as a primary endpoint when it is subjectively measured on an objective scale? I struggle with these questions now that my eyes have been opened.
I am currently caring for a patient with lupus and fibromyalgia who is suffering from terrific pain related to inflammatory arthritis and digital gangrene; she was denied disability because the insurance company cited that “pain is subjective.” My retort to them was, “…so is death.” How do you measure pain in your patients?