2011 年 37 巻 4 号 p. 253-260
The effects of hypnotics are one of the many causes of falls.However few studies have been done on a relationship between falls and hypnotics use in Japan.
We studied 109 patients who had experienced falls in hospital.The male to female ratio was 6:4,mean age was 67 years,22% of them had hepatic dysfunction,and 12% had renal dysfunction.Among them,38.5% were on hypnotics,and other frequently prescribed drugs were diuretics,analgesic antipyretics and laxatives.The incidence of falls for hypnotics was higher in subjects on the ultra-short-acting type (1.6 to 6.2%) than in those on the short-acting type (5.0 to 6.8%).For ultra-short-acting hypnotics,the incidences were similar in the daytime and nighttime,but for short-acting hypnotics,the incidence was higher in the daytime than in the nighttime,suggesting a persistent diurnal effect.
A questionnaire survey of physicians revealed that they selected hypnotics mainly based on the types of insomnia,duration of the hypnotic’s effect and the age of patients.They paid only a little attention to hepatic or renal function or metabolic pathways in patients.In order to prevent falls,we posted a recommendation in our electronic medical records system that physicians prescribe ultra-short-acting hypnotics whenever possible.Afterwards,the number of patients prescribed ultrashort-acting hypnotics increased by 75% and the number of patients who experienced falls during treatment with hypnotics decreased from 42 to 25 over a 4-month observation period.
Our findings suggest that it is important to select hypnotics for elderly patients in consideration of hepatic function,which may influence the lingering effects of hypnotics.