PROLONGED TREATMENT WITH ORAL RETINOIDS IN ADULTS - NO INFLUENCE ON THE FREQUENCY AND SEVERITY OF SPINAL ABNORMALITIES

It is generally accepted that the spine is the site of predilection fo r retinoid-induced skeletal abnormalities. However, the reported preva lence of skeletal problems varies widely. To investigate the frequency and severity of retinoid-induced spinal abnormalities, all records of patients who underwent spinal radiographs at the request of the depar tment of dermatology between 1983 and 1993 were reviewed. This group o f 135 patients comprised the total population of retinoid-treated pati ents and those patients who were investigated for possible future reti noid treatment. The mean treatment period in the total group was 30 mo nths and the mean cumulative dose of retinoid was 31 g. In 50 patients the treatment period was greater than or equal to 24 months with 30 p atients being treated for more than 48 months. Baseline radiographs we re available from 26 patients and these were compared with the most re cent X-rays during treatment. The mean treatment period in this 'prosp ective group' was 25 months and the mean cumulative dose of retinoid w as 25 g. The prevalence of diffuse idiopathic skeletal hyperostosis (D ISH), degenerative changes and osteoporosis in the total group was res pectively 16%, 53% and 29%. There was no statistically significant rel ation between the duration of treatment or the cumulative dose and the prevalence or severity of DISH, degenerative changes and osteoporosis . Only the age of the patients was significantly related to the freque ncy and severity of skeletal abnormalities. In the 'prospective group' , again, no important changes were observed between the radiographs at baseline and during treatment. In this study no relation whatsoever b etween spinal abnormalities and prolonged oral retinoid treatment coul d be established. The performance of annual routine spinal radiographs during retinoid treatment is not necessary in our opinion. Additional controlled and prospective studies on spinal and extraspinal skeletal abnormalities are required to develop definitive screening guidelines for patients submitted to long-term retinoid treatment.