Table 2.
Comparisons in the cumulative incidence and prevalence of episodes of antidepressant use in adults ≥65 years between regions and countries
| Elderly population | Canada | USA | UK | Taiwan | ||
| Total elderly population | Ontario sample (Admin. data)*† |
Montreal sample (Admin. data)*† |
Quebec city and Montreal (EMR data)‡ |
Boston (EMR data)‡ |
CPRD sample (EMR data)†‡ |
NHIRDB (Admin. data)* |
| 405 141 | 120 777 | 28 273 | 83 394 | 241 339 | 103 400 | |
| All users of antidepressants§ | ||||||
| No of users | 108 577 | 23 422 | 4450 | 17 359 | 24 858 | 24 239 |
| Prevalence in elderly (%) | 26.8 | 19.4 | 15.7 | 20.8 | 10.3 | 23.4 |
| New episodes of antidepressant use¶ | ||||||
| Number of new users | 60 366 | 13 303 | 1308 | 10 131 | 15 868 | 17 580 |
| Incidence in elderly (%) | 14.9 | 11.0 | 4.6 | 12.2 | 6.6 | 17.0 |
| Age-standardised -incidence (%) | 15.3 | 12.1 | 4.7 | 12.3 | 6.6 (reference) | 18.6 |
| Sex-standardised incidence (%) | 14.9 | 11.0 | 4.6 | 12.1 | 6.6 (reference) | 17.0 |
| Demographics | ||||||
| Between 65 and 74 years old | 32 115 (53.2%) | 5713 (42.9%) | 699 (53.4%) | 5826 (57.5%) | 7129 (44.9%) | 8811 (50.1%) |
| ≥75 years | 28 251 (46.8%) | 7590 (57.1%) | 609 (46.6%) | 4305 (42.5%) | 8739 (55.1%) | 8769 (49.9%) |
| Female | 36 884 (61.1%) | 8986 (67.5%) | 853 (65.2%) | 6136 (60.6%) | 10 045 (63.3%) | 9539 (54.3%) |
*Administrative data are retrieved from population-based health insurance claims for medical visits and prescriptions.
†Ontario represents a 20% random sample of elderly, Montreal represents a 25% annual random sample of Montreal residents and the UK represents a 10% random sample of elderly in the CPRD.
‡EMR data are extracted from primary care clinic electronic health records in the USA (Partners), Quebec (MOXXI) and the UK (Clinical Practice Research Database).
§All users include persons with an active prescription or dispensed supply of antidepressants between 2007 and 2008 as well as all new users between the period 2009 and 2014.
¶New episodes of use of antidepressants were defined as no prescription or dispensing of an antidepressant in the 2 years prior to the first antidepressant in the period N2009–2014.
CPRD, Clinical Practice Research Datalink; EMR, electronic medical record; MOXXI, Medical Office of the 21stst Century; NHIRDB, National Health Insurance Research Database.