huop5489 2010-1-18 09:58
老年人喝綠茶與憂鬱症機率較低有關
作者：Laurie Barclay, MD
出處：WebMD醫學新聞
December 29, 2009 — 根據一項發表於12月號美國臨床營養期刊的斷面性研究結果，居住於社區的老年族群，攝取較多綠茶與憂鬱症狀盛行率較低有關。
日本仙台Tohoku大學生化工程研究所的Hideko Takahashi與其同事們寫到，綠茶被報告具有許多好處（例如對抗壓力反應與抗發炎作用）。雖然這些功能可能與憂鬱症狀的發展及進展有關，但目前並沒有針對攝取綠茶與社區居民憂鬱症狀的關連性研究。
這項研究的目的是針對1,058位居住在社區、70歲以上喝綠茶的高齡日本居民，評估喝綠茶與憂鬱症之間的關係。使用自填問卷來決定綠茶攝取量。以30個問題的老年憂鬱評量表來評估憂鬱症狀，以11分作為輕重度憂鬱症狀閾值，以14分作為嚴重憂鬱症狀的閾值。使用抗憂鬱藥物被認定是憂鬱症狀的代表。
在這個群體中，34.1%罹患輕重度憂鬱症狀，而20.2%有嚴重憂鬱症狀。在校正影響因子後，相較於綠茶攝取量少於每天1杯者，每天攝取2~3杯，發生輕重度憂鬱症狀勝算比為0.96（95%信賴區間[CI]為0.66-1.42），每天4杯以上的為0.56（95% CI為0.39-0.81；P=0.001）。嚴重憂鬱症狀部分也有類似的發現。
研究作者們寫到，更頻繁地攝取綠茶與社區高齡居民憂鬱症狀盛行率較低有關。
這項研究的限制包括斷面性研究設計，無法判斷因果關係；可能的影響因子；以及缺乏精神狀況、症狀、或是治療數據。除此之外，參與者們那些未接受評估的人們更有主動性且健康，最後是老年憂鬱量表並非被設計用於憂鬱病程的臨床診斷。
研究作者們的結論是，在目前這項研究，攝取較多的綠茶（以自填問卷評估）與社區高齡居民的憂鬱症狀盛行率較低有關。這項發現代表攝取綠茶可能具有預防憂鬱症狀的潛力。不過，仍需要前瞻性隨機分派研究來釐清其間的因果關係。
日本教育、文化、運動、科學與科技署；日本粥狀動脈硬化預防基金會、健康、勞工福利省贊助這項研究。研究作者們表示已無相關資金上的往來。
Green Tea Drinking in Elderly Linked to Lower Risk for Depression
By Laurie Barclay, MD
Medscape Medical News
December 29, 2009 — More frequent consumption of green tea is associated with a lower prevalence of depressive symptoms in the community-dwelling older population, according to the results of a cross-sectional study reported in the December issue of the American Journal of Clinical Nutrition.
"Green tea is reported to have various beneficial effects (e.g., anti–stress response and anti-inflammatory effects) on human health," write Hideko Takahashi, from Tohoku University Graduate School of Biomedical Engineering in Sendai, Japan, and colleagues. "Although these functions might be associated with the development and progression of depressive symptoms, no studies have investigated the relation between green tea consumption and depressive symptoms in a community-dwelling population."
The objective of the study was to evaluate the association between green tea drinking and depressive symptoms in 1058, community-dwelling, elderly Japanese subjects 70 years or older who widely consumed green tea. A self-administered questionnaire was used to determine green tea intake. The 30-item Geriatric Depression Scale was used to evaluate depressive symptoms, with a cutoff point of 11 indicating mild and severe depressive symptoms and a cutoff value of 14 indicating severe depressive symptoms. Antidepressant use was also considered to indicate depressive symptoms.
In this cohort, 34.1% had mild and severe depressive symptoms, and 20.2% had severe depressive symptoms. Compared with green tea consumption of 1 or less cup per day, odds ratios for mild and severe depressive symptoms were 0.96 for 2 to 3 cups (95% confidence interval [CI], 0.66 - 1.42) and 0.56 for 4 or more cups of green tea per day (95% CI, 0.39 - 0.81; P for trend = .001), after adjustment for confounding factors. Similar associations were seen for severe depressive symptoms.
"A more frequent consumption of green tea was associated with a lower prevalence of depressive symptoms in the community-dwelling older population," the study authors write.
Limitations of this study include cross-sectional design, preventing causal inferences; possible confounding factors; and lack of data on other psychiatric conditions, symptoms, or treatments. In addition, participants were more active and healthy than those who did not undergo the assessment, and the Geriatric Depression Scale is not designed for making a clinical diagnosis of depressive episodes.
"In the present study, higher green tea consumption (as measured by self-administered questionnaires) was significantly associated with a lower prevalence of depressive symptoms in community-dwelling elderly individuals," the study authors conclude. "This finding suggested that the consumption of green tea may have a potentially beneficial effect on the prevention of depressive symptoms. A prospective study or randomized trials are required to clarify the causality."
The Ministry of Education, Culture, Sports, Science and Technology of Japan; the Japan Atherosclerosis Prevention Fund; and the Ministry of Health, Labor, and Welfare of Japan supported this study. The study authors have disclosed no relevant financial relationships.
Am J Clin Nutr. 2009;90:1615-1622.