Factors that affect stabilisation times of canine spontaneous hypoadrenocorticism

Abstract

The objective of this retrospective study was to examine factors that may have affected the stabilisation times of 50 dogs with spontaneous hypoadrenocorticism that were being treated with fludrocortisone acetate, with particular emphasis on dosing frequency and the concurrent use of prednisolone. Stabilisation was defined as an absence of clinical signs with a sodium:potassium ratio >27:1 and both electrolyte concentrations within a laboratory reference range. It was found that the median time till stabilisation was three months. The frequency of fludrocortisone treatment (once, twice or changed from once to twice a day) had no effect on the stabilisation time. The two groups of dogs that were started and stabilised on once a day or twice a day dosing had a median stabilisation time of two months. However, dogs that failed to stabilise on once a day dosing of fludrocortisone and were then changed onto twice a day dosing then stabilised a median of one month later. Concurrent use of prednisolone resulted in significantly faster stabilisation times. It was concluded that dogs with hypoadrenocorticism should be continued on prednisolone therapy until they are stabilised. If a dog is failing to stabilise on once a day fludrocortisone acetate, a change to twice a day administration could be considered.

Prednisolone dosages in Addisonian dogs after integration of ACTH measurement into treatment surveillance

“…At stabilisation, the range of eACTH concentrations (< 2.2-12.8 pmol/l) was comparable to concentrations determined in healthy young (< 2.2-8.4 pmol/l) and adult (< 2.2-9.1 pmol/l) dogs (3,20). The final median prednisolone substitution dose was 0.06 mg/kg/day, which is markedly lower than the 0.18 (22), 0.2 (17) and 0.35 mg/kg/day (29) in preceding studies. The fact that at stabilisation 11 of 13 dogs on fludrocortisone required additional glucocorticoids is in line with the study of Kintzer and Peterson (17), where discontinuation was possible in only 11 % of the patients and a recent not fully published prospective cross-over trial (33).…”

“…At the end of the treatment period, 58 % of the patients had eACTH concentrations above 22 pmol/l suggesting inappropriate supplementations. Compatible, the discontinuation of concurrent prednisolone resulted in significantly longer stabilisation times in a recent study (29).…”

“…Suggested initial maintenance dosages in combination with fludrocortisone range from 0.1 to 0.5 mg/kg/day SID (4,15,19,23,27,31) and from 0.1 to 0.22 mg/kg BID (6,18). In three retrospective follow-up studies daily basal prednisolone/prednisone was slowly tapered and discontinued in up to 58 % of the dogs (17,22,29). Klein and Peterson (18) state that the prednisone doses that enhance the patients' wellbeing but prevent side effects, may be very small.…”

How best to treat Addison's disease in dogs?

“…Some of these dogs (14 per cent) were eventually switched to DOCP for a variety of reasons (Kintzer and Peterson 1997). In a paper summarised on p 98 of this issue of Veterinary Record , Roberts and others (2016) were also able to successfully stabilise 90 per cent of their patients with fludrocortisone. There are significant differences between both medications, including cost, and in most countries DOCP is sparingly used, because it is considerably more expensive than fludrocortisone; however, in a small number of countries fludrocortisone is actually more expensive than DOCP.…”

“…Our knowledge regarding best practice for treating hypoadrenocorticism has increased due to the data captured by Roberts and others (2016). The paper provides interesting insight into how best to use fludrocortisone in patients.…”