Insulin and oral agents for managing cystic fibrosis-related diabetes

 

Abstract

Background

Insulin therapy is recommended by the Cystic Fibrosis Foundation when cystic fibrosis-related diabetes has been diagnosed. Diagnosis is based on an elevated fasting blood glucose level greater than 6.94 mmol/liter (125 mg/deciliter) or symptomatic diabetes for random glucose levels greater than 11.11 mmol/liter (200 mg/deciliter).

Objectives

To examine the evidence that, when treated with agents for managing diabetes, people with cystic fibrosis improve their sugar metabolic control resulting in beneficial impact on lung function and the ability to maintain optimal weight.

Search methods

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings.

We also handsearched abstracts from pulmonary and North American Cystic Fibrosis Conference symposia.

Date of the most recent search of the Group's Trials Register: April 2008.

Selection criteria

Randomized controlled trials comparing all methods of diabetes therapy in people with cystic fibrosis.

Data collection and analysis

Two authors independently extracted data and assessed the risk of bias from the single included study.

Main results

Twenty references to fourteen studies were identified by the searches. One study (seven participants) comparing insulin with oral repaglinide has been included. We were unable to present the data graphically as they had been more appropriately reported in the primary paper, which states that at the doses given (not comparable), insulin was more beneficial than repaglinide to people with cystic fibrosis-related diabetes. Three incidences of hypoglycemia (two in the insulin group and one in the repaglinide group) were reported, all occurring an average of four hours after the test meal and resolved without further treatment.

Authors' conclusions

While some cystic fibrosis centers use oral medications to help control diabetes, insulin therapy is the recommended and most widely used treatment method. This systematic review to date only identifies one short-term (five-hour) study, with little clinical relevance relating to the poor long-term prognosis recognized for cystic fibrosis-related diabetes. The need for a multicentre randomized controlled trial assessing both the efficacy of insulin or other insulin-releasing or insulin-sensitizing medications and their possible adverse effects in managing cystic fibrosis-related diabetes and which relates more realistically to long-term glycemic control continues to be a priority.

 

Plain language summary

Insulin and oral agents for managing cystic-fibrosis related diabetes

Cystic fibrosis is a serious genetic disorder damaging the lungs and pancreas (an organ essential for sugar metabolism). People with cystic fibrosis need high calorie diets to manage breathing difficulties resulting from their lung damage; optimizing sugar metabolism is, therefore, an important therapeutic goal. Adequate sugar metabolism is linked to outcome measures such as managing breathing difficulties and maintaining ideal body weight. We were only able to include one randomized trial which met the inclusion criteria (post-meal glucose control) in this review. This trial was short term (five hours post-meal) with only seven participants with cystic fibrosis-related diabetes who had normal fasting blood sugars. The trial reported significant results in favour insulin over repaglinide for blood glucose levels at five hours post-meal, but the amounts of insulin and repaglinide received were not comparable and this may lead to bias in the results. A small number of cases of hypoglycemia were reported, but these were resolved without further treatment.

 

摘要

背景

以胰島素(insulin)與口服降血糖劑控制囊性纖維化相關之糖尿病(cystic fibrosisrelated diabetes)

當有病人被診斷為囊性纖維化相關之糖尿病時，囊性纖維化基金會推薦使用胰島素療法。診斷依據禁食中的血糖濃度上升程度大於6.94 mmol/liter (125 mg/deciliter)或根據糖尿病的症狀中隨機血糖濃度大於11.11 mmol/liter (200 mg/deciliter)。

目標

檢驗當投以控制糖尿病藥物時，患有囊性纖維化的病人在醣類代謝的控制上獲得改善，並在肺功能與維持正常體重的能力上獲得助益。

搜尋策略

我們搜尋Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register ，包括來自綜合性電子資料庫的參考文獻、手動搜尋相關期刊，以及研討會摘要手冊。我們也手動搜尋了肺與北美囊性纖維化研討會的摘要記錄。最新搜尋中Group's Trials Register的日期為2007年2月。

選擇標準

所有針對囊性纖維化病患、實行一個月或以上的糖尿病療法的隨機對照試驗。

資料收集與分析

在這項回顧中沒有找到符合條件、可以被包含在內的研究。

主要結論

在搜尋中找到來自14個研究的20篇參考文獻，但因其皆非隨機對照試驗，不適合被收入本回顧。

作者結論

雖然有些囊性纖維化中心使用口服藥物療法幫助控制糖尿病(這是一個使得囊性纖維化的進程複雜化的狀況)，胰島素療法仍是被建議且最被廣泛使用的治療方法。在使用胰島素的狀況下，有報告指出肺功能改善，但尚未發現這項結果是否與糖代謝的影響有關聯性。雖然囊性纖維化基金會建議使用胰島素療法控制糖尿病，但這個系統性回顧發現仍需要一個多中心隨機對照試驗針對胰島素的效率或其他促進胰島素分泌或增加胰島素敏感度的療法以及其控制囊性纖維化相關之糖尿病的負面效果。

翻譯人

本摘要由臺灣大學附設醫院陳玠甫翻譯。

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

我們無法找到證據證明最適當的囊性纖維化相關之糖尿病療法。囊性纖維化是一種嚴重的遺傳疾病，造成肺部以及胰臟(一個糖代謝所必須的器官)的損傷。患有囊性纖維化的人需要高熱量飲食以控制因肺部損傷引起的呼吸困難；因此，理想的糖代謝是一個重要的治療目標。適當的糖代謝也被與其他措施諸如控制呼吸困難和維持理想體重作了連結。這篇回顧沒有找到隨機對照試驗顯示控制糖代謝的治療效果。仍需進行更多研究。