“While current recommendations are to test high risk individuals, such as the elderly, consensus of testing frequency and timing is lacking,” Associate Professor Anita Wluka from Monash University’s School of Public Health and Preventive Medicine said.
Analysis of Medicare data from 2000 to 2010 found that the rate of 25(OH) D testing had increased 94-fold, representing a financial increase from $1.02 million to $96.75 million during the period.
As a part of their study, the researchers conducted a three-year audit (from 2010 to 2012) at a major metropolitan community health centre in the western region of Melbourne. The incidence of Vitamin D deficiency varies across society, with females, the elderly, lower socioeconomic groups and migrants presenting a higher risk. To date, studies of testing patterns have not evaluated socioeconomic factors and migrant status in light of testing.
“This study aimed to examine 25(OH) D testing patterns by GPs as well as identifying patient characteristics associated with higher levels of testing. We found that 55.6 per cent of eligible patients in the study were tested for Vitamin D deficiency, which is obviously a significant proportion,” Associate Professor Wluka said.
Of these patients, the majority were female (59.8 per cent) and 65.7 per cent of migrants were tested compared to only 42.1 per cent on non-migrants. Researchers did not find a significant testing pattern between patients in most disadvantaged areas and least disadvantaged areas.
“It is important to assess and test high risk groups; however the incidence of possible over-testing needs to be considered. Evidence-based policies and improved guidelines on testing frequency are needed and could provide significant savings in annual healthcare expenditure.
“Another option could be raising the current recommended daily supplement dose of 800IU to those at risk of Vitamin D deficiency, and refraining from testing unless risk factors changed for the patient,” Associate Professor Wluka said.