Comorbidity of chronic disease and potential treatment conflicts in older people dispensed antidepressants.
OBJECTIVE
the study aimed to examine the prevalence of comorbidity, the prescribing of potentially inappropriate medications and treatment conflicts in a large sample of older people who have been dispensed an antidepressant medicine.


METHODS
a cross-sectional study of administrative claims data from the Department of Veterans' Affairs, Australia, 1 April-31 July 2007, of veterans aged > or =65 years was conducted. Comorbidities determined using the pharmaceutical-based comorbidity index, Rx-Risk-V. Concomitant medicines that may be potentially inappropriate for patients with depression and areas of treatment conflicts were determined from Australian clinical guidelines or reference compendia.


RESULTS
a total of 39,695 subjects were included, with a median of 5 comorbid conditions (inter-quartile range 3-6). Ninety percent of medicine use was attributed to the treatment of comorbid conditions. Eighty-seven percent of the study cohort was identified as having at least one comorbid condition that may cause a potential treatment conflict when an antidepressant is used. Those conditions of most concern included cardiovascular diseases, anxiety disorders, arthritis or pain management and osteoporosis.


CONCLUSIONS
we observed a high level of potentially inappropriate prescribing and treatment conflicts that may arise when caring for older patients dispensed an antidepressant with comorbidity. These have the potential to place a large number of older people with depression at increased risk for adverse events.
Quality Use of Medicines and Pharmacy Research Centre, Sansom Institute, University of South Australia, Australia. gillian.caughey@unisa.edu.au <gillian.caughey@unisa.edu.au>
Gillian Elizabeth
GE
Caughey
Elizabeth Ellen
EE
Roughead
Sepehr
S
Shakib
Robyn A
RA
McDermott
Agnes I
AI
Vitry
Andrew L
AL
Gilbert
D000368:Aged; D000369:Aged, 80 and over; D000928:Antidepressive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001007:Anxiety / Q000188:drug therapy; D001168:Arthritis / Q000188:drug therapy; D001315:Australia / Q000453:epidemiology; D002318:Cardiovascular Diseases / Q000188:drug therapy; D002908:Chronic Disease; D015897:Comorbidity; D003430:Cross-Sectional Studies; D003863:Depression / Q000188:drug therapy*; D004344:Drug Incompatibility; D005260:Female; D006801:Humans; D008297:Male; D008508:Medication Errors; D010024:Osteoporosis / Q000188:drug therapy; D010146:Pain / Q000188:drug therapy; D017410:Practice Guidelines as Topic
D000928:Antidepressive Agents