title: Natural history of pain following herpes zoster.
abstract: In a longitudinal observational study of 94 patients (39 M:55 F, mean age 69) at elevated risk for developing post herpetic neuralgia (PHN), the natural history of pain during the first 6 months after herpes zoster (HZ) rash onset was determined. Pain severity and impact were rated using pain-VAS, SF-MPQ, and MPI. Applying a definition of PHN of average daily pain >0/100 on the pain VAS during the last 48 h, 30 subjects had PHN at 6 months. These 30 subjects reported more pain and a higher SF-MPQ score (p<0.01) at study inclusion than the 64 subjects whose pain completely resolved by 6 months. At 6 months, mean daily pain in the PHN group was 11/100 (95% CI 5,16) and only nine of these subjects were still taking prescription medication for HZ pain. The rate of recovery (pain severity over time) was the same in the PHN and no-pain groups. At study inclusion, the SF-MPQ and MPI scores in our PHN group were similar to historical controls with chronic severe PHN enrolled in clinical trials, but by 6 months the scores in our PHN subjects were significantly lower than historic controls. Only two subjects met the more stringent criteria for 'clinically meaningful' PHN at 6 months (> or = 30/100 on the pain VAS). Defining PHN as average daily pain >0/100 at 6 months after rash onset appears to substantially overestimate the number of HZ patients negatively impacted by ongoing pain and disability.
authors.affiliation: UCSF Pain Clinical Research Center, Department of Neurology, University of California, San Francisco, CA 94115, USA.
authors.forename: Hans Gustav
authors.initials: HG
authors.lastname: Thyregod
authors.forename: Michael C
authors.initials: MC
authors.lastname: Rowbotham
authors.forename: Michelle
authors.initials: M
authors.lastname: Peters
authors.forename: Jessica
authors.initials: J
authors.lastname: Possehn
authors.forename: Marlene
authors.initials: M
authors.lastname: Berro
authors.forename: Karin Lottrup
authors.initials: KL
authors.lastname: Petersen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006562:Herpes Zoster / Q000175:diagnosis* / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D051474:Neuralgia, Postherpetic / Q000175:diagnosis* / Q000453:epidemiology*; D010147:Pain Measurement / Q000706:statistics & numerical data*; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012720:Severity of Illness Index