作者：Laurie Barclay, MD
出處：WebMD醫學新聞
January 8, 2009 — 根據一篇登載於1月份Gastroenterology期刊中的安慰劑控制、雙盲試驗結果，抗氧化劑補充品有效緩解慢性胰臟炎(chronic pancreatitis，CP)病患的疼痛與氧化壓力。
新德里全印度醫學科學研究中心的Payal Bhardwaj等人寫道，氧化壓力會影響CP的病理生理學，我們評估抗氧化補充品對緩解疼痛、氧化壓力的效果，以及評估CP病患的抗氧化狀態。
一系列CP病患被隨機指派接受安慰劑或者抗氧化補充品6個月，研究主要終點是疼痛緩解，次級終點是止痛劑和住院的需求；氧化壓力標記測量是硫代巴比妥酸-活性物質(thiobarbituric acid–reactive substances)與抗氧化狀態 (血漿還原鐵之能力)。
病患平均年紀為30.5 ± 10.5歲，86名男性，35人有酒精性CP，92人有原發CP；隨機指派的127名病患中，56人在安慰劑組，71人在抗氧化劑組；相較於安慰劑組，抗氧化劑組在6個月之後，每個月的平均疼痛天數顯著減少 (分別是7.4 ± 6.8天和3.2 ± 4天；P < .001; 95%信心區間， 2.07 - 6.23)。
抗氧化劑組每個月需要的止痛藥錠數也顯著減少(分別是10.5 ± 11.8錠和4.4 ± 5.8錠；P < .001; 95% CI, 2.65 - 9.65)；抗氧化劑組中，變成全無疼痛之病患有32%，安慰劑組有13%(P = .009)。
相較於安慰劑組，抗氧化劑組之硫代巴比妥酸-活性物質顯著減少、血漿還原鐵之能力增加(硫代巴比妥酸-活性物質：安慰劑組為1.2 ± 2.7 nmol/mL 、抗氧化劑組為3.5 ± 3.4 nmol/mL; P = .001; 95% CI, 0.96 - 3.55; 血漿還原鐵之能力：安慰劑組為–5.6 ± 154.9 μM游離Fe+2、抗氧化劑組為97.8 ± 134.9 μM游離Fe+2 P = .001; 95% CI, 44.98 - 161.7)。
研究作者寫道，抗氧化劑補充品有效緩解CP病患之疼痛與降低氧化壓力；減少疼痛也獲得較少的缺工人數與天數，讓病患可以有被雇用的能力。抗氧化劑在3個月時即有疼痛緩解能力。
研究限制包括主觀疼痛評估的偏差、安慰劑組的疼痛減少情況、未能追蹤者、以及缺乏有關抗氧化劑效果持續多久和應該繼續使用多久的抗氧化劑補充品的資料。
研究作者結論表示，在我們的研究中，我們並未觀察到任何明顯的藥物副作用；這可能是因為病患本身缺乏抗氧化劑。我們相信抗氧化劑治療在臨床上可以適當用於CP病患。
本研究接受印度醫學研究委員會支持。Osper藥廠免費提供藥物與安慰劑。
Antioxidants Reduce Pain, Oxidative Stress in Chronic Pancreatitis
By Laurie Barclay, MD
Medscape Medical News
January 8, 2009 — Antioxidant supplementation effectively relieves pain and oxidative stress in patients with chronic pancreatitis (CP), according to the results of a placebo-controlled, double-blind trial reported in the January issue of Gastroenterology.
"Oxidative stress has been implicated in the pathophysiology of...CP," write Payal Bhardwaj, from the All India Institute of Medical Sciences in New Delhi, and colleagues. "We evaluated the effects of antioxidant supplementation on pain relief, oxidative stress, and antioxidant status in patients with CP."
Consecutive patients with CP were randomly assigned to receive placebo or antioxidant supplementation for 6 months, with the main endpoint of the study being pain relief. Secondary endpoints were a need for analgesics and hospitalization. Oxidative stress markers measured were thiobarbituric acid–reactive substances and antioxidant status (ferric-reducing ability of plasma).
Mean age of the patients was 30.5 ± 10.5 years, 86 were men, 35 had alcoholic CP, and 92 had idiopathic CP. Of 127 patients randomly assigned, 56 were in the placebo group and 71 in the antioxidant group. Compared with the placebo group, the antioxidant group had a significantly greater decrease after 6 months in the number of painful days per month (7.4 ± 6.8 vs 3.2 ± 4 days, respectively; P < .001; 95% confidence interval [CI], 2.07 - 6.23).
The antioxidant group also had a greater reduction in the number of analgesic tablets taken per month (10.5 ± 11.8 vs 4.4 ± 5.8 tablets, respectively; P < .001; 95% CI, 2.65 - 9.65). The proportion of patients that became pain-free was 32% in the antioxidant group and 13% in the placebo group (P = .009).
Compared with the placebo group, the antioxidant group had a significantly greater reduction in the level of thiobarbituric acid–reactive substances and an increase in the ferric-reducing ability of plasma (thiobarbituric acid–reactive substances: placebo, 1.2 ± 2.7 nmol/mL vs antioxidant, 3.5 ± 3.4 nmol/mL; P = .001; 95% CI, 0.96 - 3.55; ferric-reducing ability of plasma: placebo, –5.6 ± 154.9 μMFe+2 liberated vs antioxidant 97.8 ± 134.9 μMFe+2 liberated; P = .001; 95% CI, 44.98 - 161.7).
"Antioxidant supplementation was effective in relieving pain and reducing levels of oxidative stress in patients with CP," the study authors write. "Reduction in pain also resulted in fewer man-days lost, thus providing functional employment gain to the patients. The beneficial effect of antioxidants on pain relief was noted early — at 3 months."
Limitations of the study include evaluation of pain subject to bias, reduction of pain in the placebo group, loss to follow-up, and lack of data concerning for how long the effect of antioxidants will last and for how long the antioxidant supplementation should be continued.
"We did not observe any significant adverse drug reactions due to antioxidants in our study," the study authors conclude. "This could be due to the fact that the patients were antioxidant deficient. We believe that antioxidant therapy can be prescribed in an appropriate clinical setting of CP."
This study was supported by Indian Council of Medical Research. Osper Pharmanautics provided the drug and placebo without charge.
Gastroenterology. 2009;136:149-159. |
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