Characteristics of falls producing hip fractures in nonagenarians

To evaluate the characteristics associated with falls causing hip fracture in patients 90 years of age or older (nonagenarians). A second objective was to compare these characteristics with those present in younger patients (65-79 year-olds).

Prospective, observational study.

Six hospitals in Barcelona (Spain) and its surrounding area.

105 nonagenarians diagnosed with hip fracture after a fall. Most patients were women (78; 74%), with a mean age of 92.2+/-2 years. All of them were living in the community, except for eight institutionalized patients. 221 patients aged 65 to 79 composed the younger patient's comparison group.

Characteristics of falls causing hip fracture were analyzed: location, time and the risk factor for the fall, classified as intrinsic, extrinsic or combined.

The mean number of falls in the previous year was 1.5 - 22% of the patients reported having fallen two or more times. Falls usually happened while at home (70%) and during the day (64%). An intrinsic risk factor was considered the most likely cause in 37% of the cases, an extrinsic risk factor in 35%, and a combination in 28%. Multiple stepwise logistic regression analysis showed that nonagenarians were characterized by lower BI scores, more falls happening during night time, a higher use of, benzodiazepines and diuretics, and a lower use of non-benzodiazepinic hypnotics.

Most falls causing hip fracture in nonagenarians happen during the day and at home. Falls in nonagenarians happening more frequently during nighttime, and these oldest subjects had lower BI scores, and a higher use of benzodiazepines and diuretics and less use of non-benzodiazepines hypnotics compared with the younger patients.