Iron infusions and hypophosphataemia

Dear Editor,

The article ‘Iron Infusions and Hypophosphataemia’ in the May 2023 edition of Medical Forum highlighted hypophosphataemia as a potential and important complication of intravenous iron therapy with ferric carboxymaltose. This complication is relatively common and may currently be underappreciated. We assessed patient phosphate concentrations prior to, and approximately one month after iron infusion with 1g ferric carboxymaltose.

Of the 173 patients included, 47 of 173 patients (27%) had a low phosphate concentration (<0.75mmol/L) following the infusion. In four of these patients (2%), the hypophosphataemia was severe (<0.40 mmol/L); in 43 (25%) it was mild to moderate (0.40 to 0.75 mmol/L).

There was no pre-infusion phosphate concentration which predicted the development of hypophosphataemia. Nearly all patients in the study (169 of 172), including all four patients with severe hypophosphataemia, had normal serum phosphate concentrations prior to the infusion.

Other research has reported even higher incidence of hypophosphatemia (up to 75%) following infusion with ferric carboxymaltose, with peak incidence at 1-2 weeks following the infusion (Wolf et al, 2020).

We agree with the importance of measuring and monitoring phosphate concentrations in patients who experience symptoms post iron infusion, such as fatigue, bone pain or muscular weakness. It should be noted that management is not simple and phosphate

Medicare reform must continue

Dear Editor,

I am copying you in on my open letter to Federal Health Minister Mark Butler:

Congratulations on the first real initiatives to restore the primacy of general practice in the health system.

As you will be aware, the Morrison government set up a review of Medicare but their terms of reference refused to examine the following terms: supplementation may not be helpful.

To demand a review of the Medicare schedule as applies to general practice with respect to changing the current time bands from 5 to 20 minutes and replace with 10-minute quintiles which better reflect the role of the holistic GP, reward high quality holistic care and return a better rebate to patients to preserve universal affordable access to primary health care.

Changes to Medicare bulk billing is the lifeboat general practice needed particularly in rural Australia where GPs could earn up to $150,000 more each year and preserve bulk billing for all those on a health care card.

Sadly, the working poor not on a health care card will be forced to pay Tony Abbott’s gap payment of $20 in the city and $40 in the country to get parity. Let’s hope next year’s budget will start building the Medicare ship of universal access to health care.

We must recognise the holistic GP who is more likely to be female and seeing the difficult female patient who comes in for a simple pill script but is suffering post-natal depression, she has breakthrough bleeding on the pill, she has doubts about her partner’s fidelity opening up issues of STDs.

In the setting of increased renal phosphate wasting mediated by FGF23, phosphate supplementation may actually increase urinary phosphate excretion and thus worsen or prolong hypophosphataemia (Schaefer et al. 2022). Treatment with activated vitamin D may be beneficial by mitigating secondary hyperaparathyroidism.

However, if subsequent iron infusions are required, choosing an alternative iron preparation such as ferric derisomaltose may be advisable in affected patients, in order to avoid complications such as osteomalacia.

Dr Rachel Dennis, Dr Aaron Simpson and Dr Ram Tampi Clinipath Pathology

Or the middle-aged male with early hypertension but is obese, has syndrome X with high triglycerides and truncal obesity. Low physical activity, drinks too much alcohol and pre-diabetic. Yes, we could just prescribe the blood pressure tablet and ‘kerching’, get the Medicare rebate, or allow this patient to see the pharmacist for a repeat script, or we could spend 15 minutes per consultation and start to address these issues.

Under current policies we encourage over-servicing and 6-minute medicine and totally ignore the productivity improvements that could be achieved by rewarding longer quality consultations. A bulk billing doctor now stands to earn up to 10x ($42 item 23 +$20 BB) = $620 per hour yet this government expects GPs to cope with the complicated patient with holistic care at a rebate to patients of just $42. No wonder GPs will charge a gap fee of $50, giving them an average net hourly rate of just $368.

Despite the obvious definition of stupidity (i.e. doing the same thing over and over and expecting a different result), when will the RACGP recognise that the current time bands are not fit for service and we must change to 10-minute quintiles?

The benefit is that it is revenue neutral to Treasury. Bulk billing clinics will still spend just 6 minutes per patient with no change to the budget. But quality GPs will be rewarded and patients will receive a higher rebate.

Dr Colin Hughes Former chair RACGPWA