Fall risk factors and sex differences among community-dwelling elderly individuals in Japan. A Kameoka study

Abstract

Although factors associated with falls might differ between men and women, no large-scale studies were conducted to examine the sex difference of risk factors for falls in Japanese elderly. The purpose of this study was to examine fall risk factors and sex differences among community-dwelling elderly individuals using a complete survey of the geriatric population in Kameoka city. A self-administered questionnaire survey was conducted with 18,231 community-dwelling elderly individuals aged 65 years or over in Kameoka city, Kyoto Prefecture, between July and August 2011, excluding people who were publicly certified with a long-term care need of grade 3 or higher. The questionnaire was individually distributed and collected via mail. Out of 12,159 responders (recovery rate of 72.2%), we analyzed the data of 12,054 elderly individuals who were not certified as having long-term care needs. The questionnaire was composed of basic attributes, a simple screening test for fall risk, the Kihon Check List with 25 items, and the Tokyo Metropolitan Institute of Gerontology (TMIG) index of competence with 13 items. These items were grouped into nine factors: motor function, malnutrition, oral function, houseboundness, forgetfulness, depression, Instrumental Activity of Daily Living (IADL), intellectual activities, and social role. Of all the respondents, 20.8% experienced falls within the last year, and 26.6% were classified as having high fall risk. Fall risk increased with age in both sexes, and risk in all age groups was higher for women than for men. All factors were significantly associated with fall risk in both sexes. After controlling for these factors, a significant relationship was found between fall risk and motor function, malnutrition, oral function, forgetfulness, depression, and IADL in men and motor function, oral function, forgetfulness, depression, and IADL in women. The deterioration of motor function was associated with three-times-higher risk than non-deterioration of motor function. In addition, significant interaction was found in sex×malnutrition, oral function, IADL, and intellectual activities; malnutrition and low oral function were stronger factors in men than in women; and IADL and intellectual activities were stronger factors in women than in men. One in five community-dwelling independent elderly individuals experienced falls in the last year, and one in four had high fall risk. We found a significant relationship between fall risk and the nine factors, particularly deterioration of motor function in both sexes. Sex difference was observed for fall risk factors; therefore, a sex-specific support policy for fall prevention is necessary.