Undertreatment of osteoporosis in persons with dementia? A population-based study.

UNLABELLED: In this population-based study of more than 2,600 elderly, people with dementia received less preventive treatment for osteoporosis compared to people without dementia, although osteoporotic fractures were more common in patients with dementia. Thus, our results indicate an undertreatment of osteoporosis in dementia. INTRODUCTION: This study compares the use of osteoporosis drugs in elderly with and without dementia, taking into account osteoporotic fractures and type of housing. METHODS: We analyzed data from the baseline examination (2001-2004) of The Swedish National Study on Aging and Care- Kungsholmen (SNAC-K), Stockholm, Sweden. Participants were aged ≥ 66 years (n = 2610). We analysed the use of bisphosphonates, raloxifene, and calcium/vitamin D combinations in relation to clinically based dementia diagnosis. Information about osteoporotic fractures during the previous 4 years was obtained from the Swedish National Patient Register. We used logistic regression to analyze the association between dementia status and use of osteoporosis drugs. RESULTS: Osteoporosis drugs (mainly calcium/vitamin D combinations) were used by 5% of the persons with dementia and 12% of the persons without dementia. Furthermore, 25% of the persons with dementia and 7% of the persons without dementia had had at least one osteoporotic fracture during the past 4 years. After controlling for age, sex, osteoporotic fractures, and type of housing (own home or institution), persons with dementia were less likely to use osteoporosis drugs than persons without dementia (OR = 0.34; 95% CI, 0.19-0.59). CONCLUSIONS: Our results indicate an undertreatment of osteoporosis in persons with dementia, although osteoporotic fractures are common among these patients.

Amino acid repetitions in the dihydropteroate synthase of Streptococcus pneumoniae lead to sulfonamide resistance with limited effects on substrate K(m).

Sulfonamide resistance in Streptococcus pneumoniae is due to changes in the chromosomal folP (sulA) gene coding for dihydropteroate synthase (DHPS). The first reported laboratory-selected sulfonamide-resistant S. pneumoniae isolate had a 6-bp repetition, the sul-d mutation, leading to a repetition of the amino acids Ile(66) and Glu(67) in the gene product DHPS. More recently, clinical isolates showing this and other repetitions have been reported. WA-5, a clinical isolate from Washington State, contains a 6-bp repetition in the folP gene, identical to the sul-d mutation. The repetition was deleted by site-directed mutagenesis. Enzyme kinetic measurements showed that the deletion was associated with a 35-fold difference in K(i) for sulfathiazole but changed the K(m) for p-aminobenzoic acid only 2.5-fold and did not significantly change the K(m) for 2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine pyrophosphate. The enzyme characteristics of the deletion variant were identical to those of DHPS from a sulfonamide-susceptible strain. DHPS from clinical isolates with repetitions of Ser(61) had very similar enzyme characteristics to the DHPS from WA-5. The results confirm that the repetitions are sufficient for development of a resistant enzyme and suggest that the fitness cost to the organism of developing resistance may be very low.