Natural history of pain following herpes zoster.
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.
Thyregod
Hans Gustav
HG
UCSF Pain Clinical Research Center, Department of Neurology, University of California, San Francisco, CA 94115, USA.
Rowbotham
Michael C
MC
Peters
Michelle
M
Possehn
Jessica
J
Berro
Marlene
M
Petersen
Karin Lottrup
KL
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