| 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | p-value | |
| Age years# | |||||||||||
| <40 | 499 (2.27) | 540 (2.42) | 615 (2.73) | 599 (2.63) | 681 (2.96) | 703 (3.02) | 802 (3.41) | 812 (3.46) | 957 (4.12) | 875 (3.81) | <0.001 |
| 40–49 | 466 (8.06) | 470 (7.86) | 513 (8.27) | 524 (8.12) | 617 (9.26) | 680 (9.88) | 782 (11.07) | 861 (11.96) | 942 (12.9) | 913 (12.33) | <0.001 |
| 50–59 | 740 (15.58) | 814 (16.72) | 799 (16.12) | 825 (16.34) | 872 (16.91) | 1000 (18.85) | 1008 (18.53) | 1099 (19.76) | 1298 (22.72) | 1372 (23.33) | <0.001 |
| 60–69 | 1464 (37.41) | 1564 (40.04) | 1495 (37.96) | 1606 (40.2) | 1614 (39.89) | 1755 (42.67) | 1864 (43.88) | 2132 (48.16) | 2422 (53.45) | 2538 (55.16) | <0.001 |
| 70–79 | 2831 (84.99) | 3084 (90.47) | 3228 (92.93) | 3258 (92.49) | 3333 (93.22) | 3699 (102.56) | 3931 (109.56) | 3941 (112.01) | 4409 (126.26) | 4289 (122.92) | <0.001 |
| ≥80 | 2468 (151.95) | 2910 (170.62) | 2910 (163.63) | 3038 (164.45) | 3460 (178.22) | 3610 (178.06) | 4166 (196.86) | 4504 (203.94) | 5178 (223.97) | 5292 (219.12) | <0.001 |
| Total | 8468 (20.44) | 9382 (22.23) | 9560 (22.31) | 9850 (22.56) | 10577 (23.84) | 11447 (25.31) | 12553 (27.3) | 13349 (28.79) | 15206 (32.66) | 15279 (32.69) | <0.001 |
| Male n (%) | 3800 (44.87) | 4243 (45.22) | 4285 (44.82) | 4491 (45.59) | 4870 (46.04) | 5249 (45.85) | 5731 (45.65) | 6121 (45.85) | 7086 (46.6) | 6980 (45.68) | 0.219 |
| Female n (%) | 4668 (55.13) | 5139 (54.78) | 5275 (55.18) | 5359 (54.41) | 5707 (53.96) | 6198 (54.15) | 6822 (54.35) | 7228 (54.15) | 8120 (53.4) | 8299 (54.32) |
Data are presented as n (hospitalisation rate per 100 000 inhabitants), unless otherwise stated. Incidence proportions were calculated by dividing the number of cases per year age group with the corresponding number of persons in that population group according to the National Institute of Statistics reported at December 31st each year [12]. #: significant time trend in all age groups tested for absolute number and rate estimated using Poisson regression models.