title: Prevalence of pain 6 months after surgery: a prospective observational study.
abstract: Pain after surgery is a major issue for patient discomfort and often associated with delayed recovery. The aim of the present study was to evaluate the prevalence of pain and requirement for analgesics up to 6 months after elective surgery, independent if new pain symptoms occurred after surgery or if preoperative pain persisted in the postoperative period.
  
  
  
  A prospective observational single center cohort study was conducted between January 2012 and August 2013. Eligible patients were scheduled to undergo elective surgical interventions including joint (hip, knee arthroplasty), back (nucleotomy, spondylodesis), or urological surgery (cystectomy, prostatectomy, nephrectomy). Pain was assessed on an 11-point numerical rating scale (NRS) before, on postoperative day 2 and 6 months after surgery. Clinical information was collected with structured questionnaires and by telephone interview.
  
  
  
  Six hundred and forty-four patients gave informed consent, including 54.4 % men (mean age 62.2, SD 14.3). Higher preoperative pain scores were found in patients undergoing joint (mean 7.6; 95 % confidence interval [CI]: 7.2-8.0) and back surgery (mean 7.1, CI: 6.8-7.5) than in patients prior to urological surgery (mean 2.3; CI: 1.8-2.8). After 6 months, about 50 % of patients after joint or back surgery indicated pain levels ≥3/10, compared to 15.9 % of patients after urological surgery (p < .001). 35.3 % of the patients after joint surgery and 41.3 % after back surgery still use pain medication 6 months postoperatively, in contrast to 7.3 % of patients after urological surgery. 13.6 % of patients who underwent back surgery indicated the regular intake of opioids.
  
  
  
  Our results reveal that a significant percentage of patients undergoing procedures in joint or back surgery still need pain medication up to 6 months postoperatively due to ongoing pain symptoms. Improved monitoring of pain management is warranted, especially after discharge from hospital, to improve long-term results.
  
  
  
  Clinicaltrials.gov (Identifier: NCT01488617 ); date of registration December 6th 2011.
authors.affiliation: Department of Anaesthesiology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstrasse 1, D-55131, Mainz, Germany. rita.laufenberg@unimedizin-mainz.de.
authors.forename: Rita
authors.initials: R
authors.lastname: Laufenberg-Feldmann
authors.affiliation: Department of Anaesthesiology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstrasse 1, D-55131, Mainz, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Kappis
authors.affiliation: Department of Anaesthesiology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstrasse 1, D-55131, Mainz, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Mauff
authors.affiliation: Institute for Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstrasse 1, D-55131, Mainz, Germany.
authors.forename: Irene
authors.initials: I
authors.lastname: Schmidtmann
authors.affiliation: Department of Anaesthesiology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstrasse 1, D-55131, Mainz, Germany.
authors.forename: Marion
authors.initials: M
authors.lastname: Ferner
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000700:Analgesics / Q000008:administration & dosage*; D000701:Analgesics, Opioid / Q000008:administration & dosage; D059350:Chronic Pain / Q000188:drug therapy / Q000453:epidemiology* / Q000209:etiology; D015331:Cohort Studies; D017558:Elective Surgical Procedures / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy / Q000453:epidemiology*; D057234:Preoperative Period; D015995:Prevalence; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D013997:Time Factors; D055815:Young Adult
chemical_list: D000700:Analgesics; D000701:Analgesics, Opioid
keywords: Analgesics; Chronic pain; Outcome; Postoperative pain