Phenomenon of Pain In Thalassemia: A Prospective Analysis by the Thalassemia Clinical Research Network (TCRN)

Pain is not a symptom generally associated with thalassemia. However, healthcare providers have anecdotally noted increasing patient reports of chronic pain over the last decade creating an impetus for the TCRN to conduct this prospective, observational assessment of pain in patients with thalassemia over the age of 12. Study goals include assessment of pain prevalence, severity and sites and whether these factors are impacted by age, gender or diagnosis.

Pain was assessed quarterly using the Brief Pain Inventory (BPI). Two hundred fifty-one thalassemia patients ranging in age from 12 to 71 (average age of 28.75) receiving care at one of 12 thalassemia centers across the US and Canada participated in the study. Fifty-four percent of participants were female. Diagnoses included: Beta Thalassemia (80%), E Beta thalassemia (11%), Hemoglobin H and H Constant Spring (6%) and other thalassemia conditions (3%). Eighty percent of participants were chronically transfused, 6% intermittently transfused and 14% had never been transfused. This report reviews baseline findings.

At study entry, 64% of the 251 participants reported experiencing pain over the last four weeks, of whom 21% reported pain on a daily basis. In comparison, 26% of the American public, 20 years and older, reported pain over a one month period according to National Center for Health Statistics data, 2006. Ordinal regression analysis of participant ratings of worst, least, and average pain over the last seven days demonstrated significant (p<0.001) correlation of increased age with increased pain across all categories irrespective of diagnosis, transfusion status or gender. Similarly, ordinal regression analysis revealed that pain increased with participant age and significantly correlated (p<0.001) with a negative impact of pain on patient's affect and activity as measured by the BPI interference scales. Eighty-two percent of those reporting pain indicated lower back as a site of pain. In logistic regression models, lower back (p=0.046), arm (p=0.047) and hip (p=0.009) pain significantly increased with age. The number of bodily pain sites (p=0.033) also increased with age which was determined using linear regression. Among patients reporting pain in the last seven days, 77% reported having pain for one year or longer and 26% reported pain for 5 or more years. Participants reporting pain in the last 7 days identified the following reasons for their pain: thalassemia (60%), low hemoglobin (55%), bone pain (37%) and muscle spasm (30%). Participants indicated multiple methods of managing pain including: blood transfusion (54%), rest (51%) massage (46%) and heat (39%). Medications were the most frequently cited pain intervention (72 % of participants) with the most common mediations taken being NSAIDs (71%), followed by acetaminophen (48%), short acting narcotics (24%) and long acting narcotics (11%). Twenty-five percent of participants reported they received no pain relief from medications or non-pharmaceutical treatments, and only 4% reported they received complete pain relief with treatment. Half the population reported they gained about 50% relief from pain with treatments.

These data show that pain is a significant issue for patients with thalassemia and as patient's age pain increases. Pain assessment should be conducted on a regular basis for all patients with thalassemia since neither transfusion status nor diagnosis are a reliable indicator of pain status. The study also indicates that chronic pain (pain lasting greater than one year) is an issue for thalassemia patients and underscores the need for further study of pain in this population. Analysis of pain follow up data collected at 3 month intervals post baseline is being conducted to assess whether severity levels vary over time.

Coates:Novartis: Research Funding, Speakers Bureau. Neufeld:Novartis, Inc: Research Funding; Ferrokin, Inc: Research Funding.