10. tbl. 103. árg. 2017

Review of epidemiology of fractures in the Icelandic Heart Association cohort

Úr gögnum Hjartaverndar: Nokkur atriði um faraldsfræði og áhættumat beinbrota á Íslandi

In recent years, scientific papers have been published in Osteoporosis International on the epidemiology of fractures in Iceland based on the Icelandic Heart Association cohort. We report the main results with emphasis on the major osteoporotic fractures (MOF), distal forearm, upper arm, clinical vertebral and hip. Those four types of fractures have been reported to cause about 90% of the total burden of all osteoporotic fractures. The incidence of those four fractures in the Icelandic Heart Association cohort have been used as the basis for the international fracture risk calculator “FRAX “in Iceland. “FRAX” assesses the risk of those fractures for the next 10 years in both sexes in the age group 40-90 years. FRAX Iceland was opened on the internet in the year 2013.

We emphasize the importance of previous fracture history as almost 40% of all major osteoporotic fractures occur after first MOF according to our cohort. The results demonstrate the importance of time from the first fracture as the risk of the second fracture is greater in the first two years although increased risk remains during the next 20 years. This indicates the importance of secondary prevention early after the first fracture especially amongst elderly people. These results give a good overall view about the epidemiology of fractures in Iceland in comparison with foreign studies and shows that age standardized incidence of the most important osteoporotic fracture, the hip fracture, reached a maximum around the millennium but has decreased among women until 2008 similar to what has been observed in Sweden and Denmark.

Figure I: Annual incidence of new cases of MOF in the Icelandic Heart Association group, ages 35+ years.

Figure II: Comparison of age related incidence of hip fractures in both sexes from Reykjavik, Malmö, Minnesota, England and Wales, and North Trondheim.

Figure III: Comparison of incidence of first hip fracture in the Icelandic Heart Association group, aged 70-85 years divided in five four year periods, 1989-2008. Women above, men below.

Figure IV: Risk/100,000 for a second MOF following the first one by the age of 75. The line at the bottom displays the risk of first fracture for women, by the age of 75.

Table I: Total number of fractures and fractured individuals in the group on a 26.5 year follow-up.

Table II: Estimated total number of major fractures in Iceland 2008, forearm, upperarm, spinal column, and hip fractures. 35+ year olds

Table III: Numer of individuals and the proportion that have had one or more fractures.

Table IV: First and second MOF as a proportion of all major fractures.

Table V: Survival probability of fractures after 50, estimated life expectancies are 82 years for men and 85 for women.

Table VI: 10 year mean likelihood (%) with respect to age and gender of MOF in Iceland (distal end of forearm, proximal end of upper arm, spine, and hip).

Table VII: Internal proportion (%) of MOF in the Icelandic Heart Association group.

Þetta vefsvæði byggir á Eplica