abao

作者：Deborah Brauser  
出處：WebMD醫學新聞

　　June 16, 2010 — 根據一項取自於蘇格蘭健康普查的綜向研究結果，健康、非吸菸成人，暴露在二手菸（SHS）之下可能導致精神壓力以及增加日後因精神問題住院的風險。
　　
　　主要作者，英格蘭倫敦皇家大學流行病學與公衛部門社會流行病學副教授Mark Hamer博士及其同事們寫到，這些發現強調，降低大眾的SHS暴露，對於生理健康和精神健康上都有其重要性。
　　
　　Hamer博士向Medscape精神醫學表示，在這項研究中受試者暴露最多的SHS是在家中，因此，最高的風險可能是與吸菸者同住。
　　
　　他表示，過去這個領域的研究大都使用自我通報的指標，這經常是不可靠的。我們的研究採用唾液古丁尼（cotinine）的客觀指標。再來，過去的研究都是斷面性研究，我們展現出許多縱向的關聯性，強化了我們的發現。
　　
　　這項研究於6月7日線上發表於一般精神醫學誌。
　　
　　【60%非吸菸者暴露在SHS下】
　　根據作者指出，據估計，60%美國非吸菸者有暴露在SHS下的生物跡象。除此之外，當工作場所與公共區域的吸菸限制越多時，居家的SHS暴露越來越常見。
　　
　　Hamer博士表示，雖然過去研究已經證實SHS會造成許多生理健康效應，但是其與精神健康的關聯性仍然是未知的。合理地認為暴露SHS可能對於精神健康會有影響，因為過去的研究顯示，吸菸者憂鬱機率較高且精神健康情況較差。
　　
　　在這項研究中，研究者們評估於1998年到2003年之間，自蘇格蘭健康普查取得的5560位非吸菸成人（平均年齡為49.8歲；45%是男性），以及2595位吸菸者（平均年齡為44.8歲；50.2%是男性）數據，這些人都沒有精神疾病史。非吸菸者包括從未吸菸與已戒菸者。
　　
　　非吸菸者暴露SHS程度以唾液樣本古丁尼評估；古丁尼是一種尼古丁暴露的循環生物化學標記。低SHS暴露以古丁尼濃度低於低限值（≦0.05 μg/L）定義，中低度暴露以濃度介於0.06與0.30 μg/L之間定義，中度暴露以濃度介於0.31與0.70 μg/L之間定義，高度暴露則以濃度高於15.00 μg/L定義。
　　
　　除此之外，受試者們填寫一份共12項的整體健康問卷，以分數高於3分代表精神壓力。再將6年追蹤時間內，住院病患基礎資料庫前瞻性地與普查相連結並進行評估。
　　
　　【高壓力、住院風險】
　　研究作者們報告，結果顯示，整個樣本中14.5%有精神壓力。
　　
　　在校正共變項後，斷面性數據發現，相較於低SHS暴露，非吸菸者在較高的SHS暴露下，精神壓力風險較高（勝算比為1.49；95%信賴區間[CI]為1.13-1.97）。
　　
　　在後續追蹤評估，研究者們也發現總共有41個因為憂鬱症、物質濫用、精神分裂症、非特異性譫妄或是其他精神狀況的新住院事件。
　　
　　前瞻性分析顯示，高SHS暴露（校正危險比值[HR]為2.84；95% CI為1.07-7.59），且是吸菸者（校正HR為3.74；95% CI為1.55-8.98），之後因精神疾病住院的風險增加。
　　
　　試驗作者們寫到，我們研究數據與其他新興證據相符，顯示尼古丁暴露與精神健康之間的因果關係。然而，將需要之後的試驗研究SHS暴露影響精神健康的可能途徑。
　　
　　Hamer博士報告，他的研究團隊現在計畫針對SHS與其他健康預後之間的關聯性進行研究。
　　
　　【研究引發關注】
　　伍斯特UMass紀念健康系統與麻州大學精神部門主任及教授Douglas Ziedonis醫師向Medscape精神學表示，這是個重要的研究，且是一個真正引發我們需要更廣泛地思考，當我們針對健康相關結果時，我們應該更公平地關注精神健康潛在結果。
　　
　　未參與這項研究的Ziedonis醫師表示，對我而言，我們還沒進行這類針對SHS的前瞻性、且將其與精神健康症狀相連的單純研究，這是令我驚訝的。
　　
　　他表示，最近一項研究顯示，吸菸成癮與憂鬱之間是有關係的。如果這會發生在吸菸者身上，這確實需要針對SHS進行研究。
　　
　　Ziedonis醫師也表達對這項研究量測與報告的項目有一些擔憂。因精神疾病住院本身不是個很好的指標，因為造成病患住院的原因太多。然而，這至少有某個程度上的嚴重性。所幸，未來的試驗將會針對更詳細且範圍更廣的精神問題進行研究。
　　
　　他指出，整體來說，這項研究對臨床醫師有許多重要應用。這可能提高我們詢問正在接受憂鬱症或焦慮症病患的認知，不論他們自己是否吸菸，以及如何扮演角色。現在，我們可能從未想到要問他們是否與吸菸者同住，且接著談到他們是否可以降低SHS暴露量，因為這可能潛在地惡化他們的精神健康。
　　
　　研究以及/或是作者們接受英國心臟基金會、國家健康機構、威爾康信託職業發展團體的部分贊助。蘇格蘭健康普查由蘇格蘭行政部門贊助。研究作者們與Ziedonis醫師表示沒有相關資金上的往來。


Secondhand Smoke Linked to Psychiatric Illness, Hospitalization

By Deborah Brauser
Medscape Medical News

June 16, 2010 — Exposure to secondhand smoke (SHS) can lead to psychological distress and an increased risk for future psychiatric hospitalization in healthy, nonsmoking adults, according to a new longitudinal study drawn from the Scottish Health Surveys.

These findings "emphasize the importance of reducing SHS exposure at a population level not only for physical health but for mental health," write lead author Mark Hamer, PhD, associate professor of social epidemiology in the Department of Epidemiology and Public Health at University College London, England, and colleagues.

"People [in our study] with the highest SHS exposure reported being exposed in their home," Dr. Hamer told Medscape Psychiatry. "Therefore, the highest risks are likely to be in people living with a smoker."

He noted that previous studies in this area have used self-report measures, which can often be unreliable. "Our study employed objective measures using salivary cotinine. Also, [whereas] previous studies have been cross-sectional, we demonstrate some longitudinal associations, which strengthen our findings."

The study was published online June 7 in the Archives of General Psychiatry.

60% of Nonsmokers Exposed to SHS

It is estimated that 60% of American nonsmokers have biological evidence of exposure to SHS, according to the study authors. "In addition, SHS exposure at home is growing in relative importance as restrictions on smoking in workplaces and public places spread."

Although past studies have shown that SHS can cause a number of physical health effects, its association with mental health has not been known, said Dr. Hamer. "It is reasonable to think that [SHS] exposure might have effects on mental health because previous research suggests that active smokers have higher rates of depression and poorer mental health."

For this study, the investigators evaluated data on 5560 nonsmoking adults (mean age, 49.8 years; 45% men) and 2595 smokers (mean age, 44.8 years; 50.2% men) with no history of mental illness from the 1998 and 2003 Scottish Health Surveys. Nonsmokers included both never-smokers and ex-smokers.

Exposure to SHS among nonsmokers was assessed using a salivary cotinine sample; cotinine is a circulating biochemical marker of nicotine exposure. Low SHS exposure was defined as cotinine levels below the detectable limit (?0.05 μg/L), low to moderate exposure was defined as levels between 0.06 and 0.30 μg/L, moderate exposure was defined as levels between 0.31 and 0.70 μg/L, and high exposure was defined as levels between 0.71 and 14.99 μg/L. Current smokers were defined by either self-report or cotinine levels of 15.00 μg/L or higher.

In addition, the participants filled out the 12-item General Health Questionnaires, which indicated psychological distress for scores greater than 3. A patient-based database of hospital admissions during 6 years of follow-up was prospectively linked to the surveys and was also evaluated.

High Distress, Hospitalization Risk

Results showed that "psychological distress was apparent in 14.5% of the entire sample," report the study authors.

After adjusting for covariates, the cross-sectional data found that nonsmokers had a higher risk for psychological distress after high SHS exposure (odds radio, 1.49; 95% confidence interval [CI], 1.13 - 1.97) than did those with low SHS exposure.

During the follow-up evaluation, the investigators also found a total of 41 new hospital admissions for depression, substance abuse, schizophrenia, nonspecific delirium, or other psychiatric conditions.

Prospective analyses showed that both high SHS exposure (adjusted hazard ratio [HR], 2.84; 95% CI, 1.07 - 7.59) and active smoking (adjusted HR, 3.74; 95% CI, 1.55 - 8.98) increased the risk for future psychiatric hospitalization.

"Our data are consistent with other emerging evidence to suggest a causal role of nicotine exposure in mental health," write the study authors. However, "further studies will be required to investigate the possible pathways through which SHS exposure influences mental health."

Dr. Hamer reported that his team of researchers now plans to look at associations between SHS and other health outcomes.

Study Raises Awareness

"This is an important study and one that really raises our awareness of the need to think more broadly when we're looking at health consequences, that we should equally be paying attention to mental health potential consequences," Douglas Ziedonis, MD, MPH, professor and chair of the Department of Psychiatry at the University of Massachusetts Medical School and UMass Memorial Healthcare System in Worcester, told Medscape Psychiatry.

"It was amazing for me to think that we haven't really done this type of a straightforward study looking at [SHS] in a prospective way and linking it with mental health symptoms," said Dr. Ziedonis, who was not involved with this trial.

He noted a recent study that showed a link between tobacco addiction and depression. "If that can happen with a smoker, it is definitely something that should be looked at in [SHS]."

Dr. Ziedonis also voiced some concerns with the items measured and reported on. "Psychiatric hospitalization by itself is not a great marker because there are so many factors that go into why people get hospitalized. However, it is something to at least queue up some level of severity. Hopefully, future studies will have more detail and a much broader range of psychiatric problems that might occur."

Overall, he said, the study has important implications for clinicians. "This might heighten our awareness to think about asking our patients, who we are treating for depression or anxiety, whether they smoke themselves and how that might play a role. And now, something we probably never thought about asking would be whether they're living with a smoker and then having conversations about whether they can reduce the amounts of [SHS] for the reason that it might be potentially worsening their mental health."

The study and/or authors were supported in part by the British Heart Foundation, the National Institute for Health, and a Wellcome Trust Career Development Fellowship. The Scottish Health Survey was supported by the Scottish Executive. The study authors and Dr. Ziedonis have disclosed no relevant financial relationships.

Arch Gen Psychiatry. Published online June 7, 2010.