The John Morris Diabetes Centre consumer reference group has written to Health Minister Michael Ferguson, after members learned the centre's nurse practitioner position would be abolished from June 1.

Group chairman Michael Banks said dissolving the role would result in clinic closures and service reductions to more than 100 people living with diabetes in the North, who are case managed by a nurse practitioner.

"We are alarmed and extremely disappointed by this," he said.

"We believe it is unacceptable to cut front line services from diabetes care. Abolishing this role will mean clinic closures and service reduction to an already under-serviced group of consumers."

However, a THS spokesman said the position had not been abolished, but was subject to an evaluation.

"The diabetes services team is leading the state in best practice diabetes care with their patients," he said.

"The position has not been abolished and is fixed term with an evaluation to be undertaken, which is standard practice following any trial program.

"The THS will not reduce care availability for any diabetes patients engaged with the service, which has been significantly boosted following the recruitment of two full-time endocrinologists for the first time."

Mr Banks said considering Hobart and the North West had permanent nurse practitioner roles, securing a position in the North was "in the interest of equity of service".

"These clinical services provided by a nurse practitioner cannot be substituted by another clinician. Endocrinologist do not do the work of a nurse practitioner," he said.