Clinical guidelines for the treatment of osteoporosis in Japan

Abstract

In Japan, unlike in the United States and Europe, where osteoporosis is synonymous with postmenopausal osteoporosis, the need for treatment of osteoporosis has been emphasized only for elderly women with established disease. This may be because women in the immediate postmenopausal period in Japan are virtually free of symptoms such as lumbago and signs such as spinal compression fracture. Osteoporosis typically does not manifest itself until about age 65; therefore, postmenopausal osteoporosis with vertebral fracture below the age of 60 is quite rare in Japan. Unique features of treatment for osteoporosis in Japan include rare use of estrogen replacement therapy, common use of vitamin D derivatives (especially 1alpha(OH) vitamin D) without notable side effects, and use of calcitonin almost exclusively in a low-dose intermittent regimen (20 U/week). Similarly, the use of ipriflavone is common, and calcium supplementation, especially with an active absorbable algae calcium with high bioavailability (AAACa), is effective and popular. The emphasis on the use of calcium, vitamin D, and calcitonin in the treatment of osteoporosis may be explained by an extremely low dietary calcium intake in Japan. Other factors that favor reliance on the calcium-focused approach and avoidance of estrogen include a fatalistic and naturalistic view toward menopause; an uneasiness with hormone replacement therapy; an older female population who seek osteoporosis treatment because of uneventful immediate postmenopausal periods; and the efficient absorption of calcium from the intestine with favorable response to exogenous vitamin D due to a long-standing calcium deficiency and possibly a low incidence of vitamin D-receptor abnormalities.

Osteoporosis and Apolipoprotein E Genotype in Older Adults: The Rancho Bernardo Study

“…The distribution of ApoE alleles and lumbar spine BMD was similar in the Japanese cohort to the distribution observed in Rancho Bernardo women, and the average age of the Japanese women (64 years) was similar to the mean age of the 143 younger Rancho Bernardo women (65 years). The differences may reflect the higher calcium and vitamin D intake in Rancho Bernardo women compared with Asian women, who tend to have a low calcium intake [11,12], if the ApoE association with low BMD is dependent on calcium and vitamin D exposure [13].…”

Supplemental Feeding of Difructose Anhydride III Restores Calcium Absorption Impaired by Ovariectomy in Rats

“…Because Ca is a major component of bone, it is necessary to have an adequate Ca intake. However, the Ca intake in Japan is lower than the dietary reference intake of Ca (3,4). The recommended dietary allowance for Ca of Japanese adults is 600 mg/d (5), and the Ca requirement for Japanese elderly women was estimated by balance study as 788 mg/d (3).…”

“…In Experiments 2 and 3, the calcium concentration was 3.0 g Ca/kg diet. 4 Crystallized cellulose (AVICEL; Asahi Chemical Industry, Tokyo, Japan). (%) ϭ 100 ϫ (total Ca intake Ϫ Ca excretion in feces)/total Ca intake.…”

Clinical Features Affecting the Results of Estrogen Replacement Therapy on Bone Density in Japanese Postmenopausal Women

“…uterine and breast malignancy) have reduced the acceptability of long-term estrogen replacement. The use of ERT is very low and more so with advancing age in Japanese postmenopausal women [6]. Thus, the identification of factors that may predict the response to ERT would greatly help clinicians to select those women who may benefit most from therapy.…”