Channelling of SSRIs and SNRIs use in the Tayside population, Scotland.
OBJECTIVE
To compare the user profiles of the two classes of drug, using the Tayside Medicines Monitoring Unit (MEMO) record-linkage database.


METHODS
A cohort study was carried out in the population of Tayside in Scotland. A total of 13 901 selective serotonin re-uptake inhibitor (SSRI) users and 1417 selective norepinephrine re-uptake inhibitor (SNRI) users were identified during the period of December 2000 to November 2001. A logistic regression model was used to assess the association between drug use and patients profiles and a Cox regression model was employed to examine the effect of drug use and mortality outcome.


RESULTS
Compared to SNRI patients, SSRI patients were significantly older (28.8% >/= 60 year vs. 26.2%), more likely to be female (70.9% vs. 67.8%), had more cardiovascular disease history (10.1% vs. 8.5%), but were less deprived (9.7% in the highest deprivation category vs. 12.4%), had less digestive disease (27.9% vs. 31.0%) and less history of drug overdose hospitalisation (7.2% vs. 11.9%). SNRI patients had more drug switching than SSRI patients (62.0% for recent users, 33.2% for prevalent users vs. 39.1%, 26.1%, respectively). The age-standardised mortality rates during the follow-up period until December 2003 were 5.3% for SSRI and 5.9% for SNRI users.


CONCLUSIONS
There was clear evidence that SSRI and SNRI were used in patient groups with different characteristics. This channelling sometimes favoured an improved mortality outcome and sometimes favoured a worse outcome. Overall there was no mortality difference between the two classes of drugs.
Wei
Li
L
Medicines Monitoring Unit (MEMO), Division of Medicine and Therapeutics, Ninewells Hospital and Medical School, Dundee, Scotland, UK.
Chen
Ruoling
R
MacDonald
Thomas M
TM
D018759:Adrenergic Uptake Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D000328:Adult; D000367:Age Factors; D000368:Aged; D002318:Cardiovascular Diseases / Q000150:complications; D015331:Cohort Studies; D016208:Databases, Factual; D003863:Depression / Q000188:drug therapy*; D004066:Digestive System Diseases / Q000150:complications; D062787:Drug Overdose; D005260:Female; D006760:Hospitalization; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000639:trends; D009638:Norepinephrine / Q000378:metabolism*; D018579:Patient Selection; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D012606:Scotland / Q000453:epidemiology; D017367:Selective Serotonin Reuptake Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D012737:Sex Factors
D018759:Adrenergic Uptake Inhibitors; D009638:Norepinephrine; D017367:Selective Serotonin Reuptake Inhibitors