Increasing incidence of hip fracture in Tottori Prefecture, Japan: trend from 1986 to 2001.

We conducted a survey of all hip fractures in patients 35 years old and over during 1998-2001 in Tottori Prefecture, Japan, and compared them with those reported previously. The survey found 604, 671, 710, 729 patients, in 1998, 1999, 2000, and 2001, respectively. The mean age- and gender-specific incidences (per 100,000 person-years) for men were 108.0, 209.0, 449.1, and 780.0 in the age groups of 70-74, 75-79, 80-84 and over 84, respectively, and those for women were 249.1, 505.8, 1,115.4, and 2,066.4, respectively. The expected numbers of patients in 1998 were 1.23 and 1.42 times those in 1986, and those in 2001 were 1.61 and 1.48 times those in 1986, for men and women, respectively, and the increases with time for both genders were significant. It was concluded that there was a significant increase in the incidence rates of hip fracture from 1986 to 2001.