Comparative estimates of cost and quality-adjusted life year (QALY) in three adult groups revealed that vitamin D3 supplementation was most beneficial for the over-70s, reducing their risk of mortality, while also being cost-effective, the authors write in BMJ Nutrition, Prevention & Health.
They assert that vitamin D deficiency, as measured by serum 25(OH)D, is particularly high among older Irish adults and especially the over-70s (13% of the Irish population), who are considered to be the main ‘at risk’ group. As a consequence, there is growing interest in the cost-effectiveness of vitamin D to disease prevention.
Their analysis determined that vitamin D treatment for ‘at risk’ adults that suffer year-round deficiencies, could potentially reduce annual healthcare costs from a total of approximately £7.2m (€8.4m) to approximately £4.8m (€5.6m).
In addition, clinical data suggests supplementation may decrease all-cause mortality by 7% (with 4.2% attributable to reduced cancer mortality) and reduce hip fractures by 16% (and related excess mortality) and non-hip/ less severe fractures by around 20%.
Researchers analysed data from a GP-monitored Irish public health programme and considered three age groups (≥50 years, ≥60 years and ≥70 years), including both male and female subjects. Annual mortality probability and expected life expectancy were determined for all ages.
The modelling protocol considered supplementation and healthcare costs and assumed “patient identification and treatment would take some years to achieve”.
It was assumed that the average annual healthcare cost would be the cost of treating all the eligible patients plus the cost of patient identification (a serum 25(OH)D measurement in order to identify the ‘at risk’ population).
Only patients GP assessed as having year-round deficiency were treated with vitamin D3 supplementation. Monitored vitamin D deficiency was assumed to be treated with vitamin D3 4000 IU daily for up to 10 weeks, followed by 800 IU daily thereafter.
Average UK end-of-life cancer costs were applied to Irish invasive cancer deaths, using the method of purchasing power parity (PPP), with inflation of healthcare costs allied to European 2020 values.
Cost and health benefits
The authors determined that vitamin D3 ‘drugs’ represent the largest healthcare expense (within the analysis parameters) and accounted for 40% of the total annual costs. However, they say that costs can be offset by reducing avoidable fractures and end-of-life cancer care in the high-risk group.
All groups fell below the usually acceptable cost-effectiveness threshold of £17,000 (€20,000), but cost benefits and improved health prognosis were more apparent among subjects in the older group (70-plus).
Approximately 84% of observed annual healthcare cost-savings can be attributed to fractures avoided, they write, while the remaining 16% are due to reductions in end-of-life care costs as a result of lower invasive cancer deaths.
“Approximately 61% of the reduction in mortality was due to the reduction in cancer mortality,” the report says. “Invasive cancers constitute approximately 55% of all cancers and 33% of the reduction in mortality was due to the reduction in invasive cancer mortality”, it adds.
Results support the argument for general supplementation in predetermined ‘at risk’ groups, although the Hip Fracture database suggests the definition is prohibitive and may require revision.
While the analysis established the benefits of vitamin D3 in older adults, the authors nevertheless conclude that supplementation “is likely to be clinically beneficial in deficiency but have little or no benefit for those who are replete in the vitamin”.
Source: BMJ Nutrition, Prevention & Health
Published online: doi:10.1136/bmjnph-2021-000382
‘Cost-effectiveness of vitamin D3 supplementation in older adults with vitamin D deficiency in Ireland’
Laurence Francis Lacey et al.