The use of prescribed pain medication during six or twelve months prior to the initiation of duloxetine therapy

Abstract

Duloxetine is indicated for treatment of major depressive disorder (MDD), general anxiety disorder (GAD), diabetic peripheral neuropathic pain (DPNP), and fibromyalgia. It has also been prescribed for pain relief for chronic lower back pain (CLBP) and osteoarthritis. For each of these conditions, this study assessed the utilization of pain medications prior to patients initiating duloxetine. Employing a retrospective cohort design and administrative claims data, we identified duloxetine initiators (under-age-65 commercially insured and age-65+ Medicare supplemental insured) between October 1, 2004 and December 31, 2005 who had any of the 6 medical conditions mentioned above during the 12 months prior to initiation of duloxetine. The first duloxetine dispense date was set as the “index date”. Patterns of use of pain medications during 6 and 12 months prior to index date were compared between cohorts. Among commercially-insured duloxetine users (n = 45,076, mean age = 46) antidepressants were more commonly used in patients with MDD (79%) and GAD (77%), and less among patients in other cohorts (ranging from 38% to 45%) during 6 months prior to index date; selective serotonin reuptake inhibitors accounted for about half of antidepressants. Anticonvulsants utilization was highest in patients with DPNP (44%), GAD (38%) and MDD (35%), but similar in other disease states (ranging from 22% to 24%). Patients had similar opioid and non-steroidal anti-inflammatory drugs (NSAIDs) utilization regardless of condition. Medicare-insured patients (n = 8,051, mean age = 73.5) were more likely to use anticonvulsants (33% vs. 26%, p < 0.001), opioids (53% vs. 41%, p < 0.001) and NSAIDs (31% vs. 24%, p < 0.001) than those commercially-insured. Patterns of utilization of pain medication across disease states were very similar between Medicare- and commercially-insured patients and between 12-month and 6-month prior to index date. The findings from this analysis indicate that patients had been dispensed several types of pain medications prior to duloxetine initiation across disease states. Duloxetine is indicated for treatment of major depressive disorder (MDD), general anxiety disorder (GAD), diabetic peripheral neuropathic pain (DPNP), and fibromyalgia. It has also been prescribed for pain relief for chronic lower back pain (CLBP) and osteoarthritis. For each of these conditions, this study assessed the utilization of pain medications prior to patients initiating duloxetine. Employing a retrospective cohort design and administrative claims data, we identified duloxetine initiators (under-age-65 commercially insured and age-65+ Medicare supplemental insured) between October 1, 2004 and December 31, 2005 who had any of the 6 medical conditions mentioned above during the 12 months prior to initiation of duloxetine. The first duloxetine dispense date was set as the “index date”. Patterns of use of pain medications during 6 and 12 months prior to index date were compared between cohorts. Among commercially-insured duloxetine users (n = 45,076, mean age = 46) antidepressants were more commonly used in patients with MDD (79%) and GAD (77%), and less among patients in other cohorts (ranging from 38% to 45%) during 6 months prior to index date; selective serotonin reuptake inhibitors accounted for about half of antidepressants. Anticonvulsants utilization was highest in patients with DPNP (44%), GAD (38%) and MDD (35%), but similar in other disease states (ranging from 22% to 24%). Patients had similar opioid and non-steroidal anti-inflammatory drugs (NSAIDs) utilization regardless of condition. Medicare-insured patients (n = 8,051, mean age = 73.5) were more likely to use anticonvulsants (33% vs. 26%, p < 0.001), opioids (53% vs. 41%, p < 0.001) and NSAIDs (31% vs. 24%, p < 0.001) than those commercially-insured. Patterns of utilization of pain medication across disease states were very similar between Medicare- and commercially-insured patients and between 12-month and 6-month prior to index date. The findings from this analysis indicate that patients had been dispensed several types of pain medications prior to duloxetine initiation across disease states.