BACKGROUND: In patients with chronic pain due to diabetic peripheral neuropathy (DPN) or postherpetic neuralgia (PHN), pregabalin treatment results in pain relief and improved patient function/quality of life (QoL). Few studies, however, have examined the exact relationship between pain relief and improvements in patient function/QoL. It is unclear, for example, whether pregabalin has a direct independent effect on patient function/QoL or whether improvements in function/QoL are an indirect consequent of pain relief. OBJECTIVES: To determine whether improvements in function/QoL in response to pregabalin treatment are related to the extent of pain relief in patients with neuropathic pain due to DPN or PHN and to determine whether pregabalin has a direct independent effect on patient function/QoL that is distinct from its effects on pain. METHODS: Data from 11 randomized, double-blind, placebo-controlled trials of pregabalin for the treatment of DPN or PHN were pooled for this analysis. Changes in patient function/QoL scores were plotted according to the extent of pain relief to assess whether greater levels of pain relief were associated with greater improvement in function/QoL. A novel mediation analysis was used to asses to what extent the effects of pregabalin on function/QoL scores are a direct treatment effect as opposed to an indirect effect mediated through improvements in pain or sleep. RESULTS: Moderate-to-substantial pain relief (a ≥30% decrease in pain) in response to pregabalin treatment was associated with significant (P < 0.05) improvements in 36-Item Short Form Health Survey (SF-36) scores (used to assess patient function/QoL). In many patients, greatest improvement in SF-36 scores was reported by patients achieving ≥50% decrease in pain. Analysis of Patient Global Impression of Change scores revealed a similar trend, where >80% of patients who achieved substantial pain relief also reported their status as much or very much improved. A substantial direct pregabalin treatment effect was evident for many SF-36 domains that could not be explained by pain relief or improvement in sleep. CONCLUSIONS: In patients with chronic pain due to DPN or PHN, improvements in patient function/QoL in response to pregabalin treatment are correlated with the extent of pain relief. However, such improvements in function/QoL are not mediated entirely through pain relief but are the result of a combination of pregabalin's effects on pain and sleep disturbance and a direct effect on patient function itself.
BACKGROUND: In patients with chronic pain due to diabetic peripheral neuropathy (DPN) or postherpetic neuralgia (PHN), pregabalin treatment results in pain relief and improved patient function/quality of life (QoL). Few studies, however, have examined the exact relationship between pain relief and improvements in patient function/QoL. It is unclear, for example, whether pregabalin has a direct independent effect on patient function/QoL or whether improvements in function/QoL are an indirect consequent of pain relief. OBJECTIVES: To determine whether improvements in function/QoL in response to pregabalin treatment are related to the extent of pain relief in patients with neuropathic pain due to DPN or PHN and to determine whether pregabalin has a direct independent effect on patient function/QoL that is distinct from its effects on pain. METHODS: Data from 11 randomized, double-blind, placebo-controlled trials of pregabalin for the treatment of DPN or PHN were pooled for this analysis. Changes in patient function/QoL scores were plotted according to the extent of pain relief to assess whether greater levels of pain relief were associated with greater improvement in function/QoL. A novel mediation analysis was used to asses to what extent the effects of pregabalin on function/QoL scores are a direct treatment effect as opposed to an indirect effect mediated through improvements in pain or sleep. RESULTS: Moderate-to-substantial pain relief (a ≥30% decrease in pain) in response to pregabalin treatment was associated with significant (P < 0.05) improvements in 36-Item Short Form Health Survey (SF-36) scores (used to assess patient function/QoL). In many patients, greatest improvement in SF-36 scores was reported by patients achieving ≥50% decrease in pain. Analysis of Patient Global Impression of Change scores revealed a similar trend, where >80% of patients who achieved substantial pain relief also reported their status as much or very much improved. A substantial direct pregabalin treatment effect was evident for many SF-36 domains that could not be explained by pain relief or improvement in sleep. CONCLUSIONS: In patients with chronic pain due to DPN or PHN, improvements in patient function/QoL in response to pregabalin treatment are correlated with the extent of pain relief. However, such improvements in function/QoL are not mediated entirely through pain relief but are the result of a combination of pregabalin's effects on pain and sleep disturbance and a direct effect on patient function itself.
Authors: DE-Hai Yin; Xiao-Chun Liang; L I Zhao; Hong Zhang; Qing Sun; Pu-Yan Wang; Lian-Qing Sun Journal: Exp Ther Med Date: 2015-06-03 Impact factor: 2.447
Authors: Robert R Edwards; Robert H Dworkin; Dennis C Turk; Martin S Angst; Raymond Dionne; Roy Freeman; Per Hansson; Simon Haroutounian; Lars Arendt-Nielsen; Nadine Attal; Ralf Baron; Joanna Brell; Shay Bujanover; Laurie B Burke; Daniel Carr; Amy S Chappell; Penney Cowan; Mila Etropolski; Roger B Fillingim; Jennifer S Gewandter; Nathaniel P Katz; Ernest A Kopecky; John D Markman; George Nomikos; Linda Porter; Bob A Rappaport; Andrew S C Rice; Joseph M Scavone; Joachim Scholz; Lee S Simon; Shannon M Smith; Jeffrey Tobias; Tina Tockarshewsky; Christine Veasley; Mark Versavel; Ajay D Wasan; Warren Wen; David Yarnitsky Journal: Pain Date: 2016-09 Impact factor: 7.926
Authors: Sherwyn Schwartz; Mila S Etropolski; Douglas Y Shapiro; Christine Rauschkolb; Aaron I Vinik; Bernd Lange; Kimberly Cooper; Ilse Van Hove; Juergen Haeussler Journal: Clin Drug Investig Date: 2015-02 Impact factor: 2.859