title: A practice-based analysis of combinations of diseases in patients aged 65 or older in primary care.
abstract: BACKGROUND
  Most evidence on chronic diseases has been collected for single diseases whereas in reality, patients often suffer from more than one condition. There is a growing need for evidence-based answers to multimorbidity, especially in primary care settings where family doctors (FD's) provide comprehensive care for a high variety of chronic conditions. This study aimed to define which disease and problem combinations would be most relevant and useful for the development of guidelines to manage multimorbidity in primary care.
  
  
  METHODS
  A practice-based cross sectional analysis of clinicians' chart reviews in 543 patients aged over 65 registered within two family practices in Ghent, Belgium. Main outcome measures were prevalence of disease and problem combinations and association strengths.
  
  
  RESULTS
  The prevalence of multimorbidity (Cumulative Illness Rating Scale >1) in the study sample is 82.6%. The most prevalent combination is hypertension-osteoarthritis (132/543). Moderate to strong associations (Yules Q > 0.50) are reported for 14 combinations but the corresponding prevalences are mostly below 5%. More than half of these associations show a contribution of a psychiatric problem or a social problem.
  
  
  CONCLUSIONS
  This study confirms the high prevalence of multimorbidity in patients aged over 65 in primary care. Hypertension-osteoarthritis is defined as a frequent combination however 94% of these patients have more than two disorders. The low prevalence of specific combinations, the high prevalence of psychiatric and social problems and the general complexity of multimorbidity will hamper the usefulness of randomized trials or guidelines at practice level. There is a need to explore new paradigms for addressing multimorbidity.
authors.affiliation: Department of Family Medicine and Primary Healthcare, Ghent University, Ghent, Belgium. Pauline.boeckxstaens@ugent.be.
authors.forename: Pauline
authors.initials: P
authors.lastname: Boeckxstaens
authors.forename: Wim
authors.initials: W
authors.lastname: Peersman
authors.forename: Gwendolyn
authors.initials: G
authors.lastname: Goubin
authors.forename: Souhila
authors.initials: S
authors.lastname: Ghali
authors.forename: Jan
authors.initials: J
authors.lastname: De Maeseneer
authors.forename: Guy
authors.initials: G
authors.lastname: Brusselle
authors.forename: An
authors.initials: A
authors.lastname: De Sutter
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001530:Belgium / Q000453:epidemiology; D003151:Community Health Centers; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000453:epidemiology*; D005194:Family Practice; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology*; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology*; D017202:Myocardial Ischemia / Q000453:epidemiology*; D010003:Osteoarthritis / Q000453:epidemiology*; D015995:Prevalence; D011320:Primary Health Care; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology*