Natural history, reasons for, and impact of low/non-adherence to medications for osteoporosis in a cohort of community-dwelling older women already established on medication: a 2-year follow-up study.

UNLABELLED: Approximately 15 % of older women on oral medications for osteoporosis could be considered for alternatives including parenteral therapies. Collection of data on socio-demographic/clinical variables is unlikely to be helpful in predicting low/non-adherence. Alternative approaches are needed to identify individuals at risk of low/non-adherence. INTRODUCTION: This study aims to identify individual patient reasons for stopping medications for osteoporosis, and to investigate whether this can be predicted from knowledge about socio-demographic/clinical data, or whether alternative approaches need to be used. METHODS: The Cohort for Skeletal Health in Bristol and Avon (COSHIBA) recruited 3200 older women from South West UK, of whom a proportion were on medications for osteoporosis at baseline. Information on self-reported adherence and reasons for low/non-adherence were collected at 6-monthly intervals over a 2-year period. Data was also collected on potential predictors of and impact of low/non-adherence. RESULTS: Two hundred thirty-three of 3200 (7.3 %) women were on medications for osteoporosis at baseline. Mean length of time on treatment prior to enrolment was 46 months. Of those on osteoporosis medications, 94.9 % were on bisphosphonates; 8.5 % reported low adherence and 21.6 % stopped their medication completely over the 2-year follow-up period. Length of time on medication at baseline did not influence rates of low/non-adherence. Reasons for low/non-adherence to bisphosphonates included side effects (53.9 %), practical reasons such as forgetting to take them (18.0 %) and beliefs about medications (20.5 %). No convincing predictors of low/non-adherence were identified. CONCLUSIONS: Approximately 15 % of older women on oral medications for osteoporosis could be considered for alternatives including parenteral therapies. This has important implications for healthcare provision. Collection of data on socio-demographic/clinical variables is unlikely to be helpful in predicting low/non-adherence. Alternative approaches are needed to identify individuals at risk of low/non-adherence to osteoporosis medications.

Vertebral fracture assessment (VFA) by lateral DXA scanning may be cost-effective when used as part of fracture liaison services or primary care screening.

SUMMARY: We identified that use of VFA may be cost-effective in either selected women from primary care or women attending after a low trauma fracture. INTRODUCTION: Lateral DXA scanning of the spine for vertebral fracture assessment (VFA) is used for research, but its wider role is unclear. We aimed to establish whether VFA is cost-effective in women based on two different scenarios: following a low-trauma fracture, and after screening of high-risk women identified in primary care. METHODS: The fracture cohort (FC) consisted of 377 women and the primary care cohort (PCC) of 251. Vertebral fractures were identified on VFA images by quantitative morphometry (QM). Outcome was cost-effectiveness of VFA, based on predicted change in clinical management defined as the identification of a vertebral fracture in a patient who otherwise falls below the threshold for treatment. FRAX treatment thresholds assessed were (1) 20/3 % thresholds and (2) National Osteoporosis Guidelines Group (NOGG) thresholds. RESULTS: As a result, 9.8 % from FC and 13.9 % from PCC were identified with vertebral fractures. Management was changed in 21 to 22/377 (5.6-5.8 %) in FC and 12 to 26/251 (4.8-10.4 %) from PCC depending on which thresholds were used. Sensitivity analyses identified medication adherence as the assumption which most influenced the model. The best-estimate cost-per-QALY for use of VFA in FC was £3,243 for 20/3 threshold and £2,130 for NOGG; for PCC, this was £7,831 for 20/3 and was cost-saving for NOGG. Further analyses to adjust for potential false-positive vertebral fracture identification with QM showed VFA was no longer cost-effective. CONCLUSION: VFA appears to be cost-effective in routine clinical practise, particularly when relatively inaccurate methods of identification of vertebral fractures are used such as QM.