title: Slower Decline in C-Reactive Protein after an Inflammatory Insult Is Associated with Longer Survival in Older Hospitalised Patients.
abstract: BACKGROUND
  Enhancing biological resilience may offer a novel way to prevent and ameliorate disease in older patients. We investigated whether changes in C-reactive protein (CRP), as a dynamic marker of the acute inflammatory response to diverse stressors, may provide a way to operationalize the concept of resilience in older adults. We tested this hypothesis by examining whether such changes could predict prognosis by identifying which individuals are at greater risk of 6-month mortality.
  
  
  METHODS
  Analysis of prospective, routinely collected datasets containing data on hospitalization, clinical chemistry and rehabilitation outcomes for rehabilitation inpatients between 1999 and 2011. Maximum CRP response during acute illness and CRP recovery indices (time and slope of CRP decay to half maximum, and to <50mg/L if peak values were greater than 50mg/L) was derived from biochemistry data. 6-month survival plots were conducted on quartiles of CRP recovery indices. Cox proportional hazards models were used to test univariate and multivariate predictors of 6-month mortality. Covariates included age, sex, number of medications, serum calcium, haemoglobin level, renal function, and the presence of previous myocardial infarction, stroke, chronic heart failure, COPD and diabetes.
  
  
  RESULTS
  3723 patients, mean age 84 years, were included. 1535 (41%) were male and 733 (20%) died during six-month follow-up. The lower an individual's peak CRP reading, and the longer the time taken for their CRP to fall, the better their 6-month survival. The time for CRP to reach half of its maximum value was the best dynamic CRP index of survival (HR 0.93 per week, 95% CI 0.89 to 0.98; p = 0.004); this remained significant even after adjustment for maximum CRP level and covariates listed above.
  
  
  CONCLUSIONS
  CRP recovery indices are associated with survival in older people; further work is required to explain differences in physiology between patients with a fast and slow CRP recovery.
authors.affiliation: Ageing and Health, University of Dundee, Ninewells Hospital, Dundee, Scotland, United Kingdom.
authors.forename: Maryam
authors.identifier: http://orcid.org/0000-0003-0081-6061
authors.initials: M
authors.lastname: Barma
authors.affiliation: Ageing and Health, University of Dundee, Ninewells Hospital, Dundee, Scotland, United Kingdom.
authors.forename: James A
authors.initials: JA
authors.lastname: Goodbrand
authors.affiliation: Dundee Epidemiology and Biostatistics Unit, Dundee University Medical Research Institute, University of Dundee, Dundee, Scotland, United Kingdom.
authors.forename: Peter T
authors.initials: PT
authors.lastname: Donnan
authors.affiliation: Health Informatics Centre; Tayside Medical Science Centre, University of Dundee, Dundee, Scotland, United Kingdom.
authors.forename: Mark M
authors.initials: MM
authors.lastname: McGilchrist
authors.affiliation: Faculty of Health Sciences and Sport, University of Stirling, Stirling, Scotland, United Kingdom.
authors.forename: Helen
authors.initials: H
authors.lastname: Frost
authors.affiliation: Ageing and Health, University of Dundee, Ninewells Hospital, Dundee, Scotland, United Kingdom.
authors.forename: Marion E T
authors.initials: ME
authors.lastname: McMurdo
authors.affiliation: Ageing and Health, University of Dundee, Ninewells Hospital, Dundee, Scotland, United Kingdom.
authors.forename: Miles D
authors.initials: MD
authors.lastname: Witham
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002097:C-Reactive Protein / Q000378:metabolism*; D005260:Female; D006760:Hospitalization; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D008297:Male; D011446:Prospective Studies; D016019:Survival Analysis
chemical_list: D002097:C-Reactive Protein