Doctors commonly view excessive daytime sleepiness as a cardinal sign of disturbed or inadequate sleep. But a new study suggests it could also signal depression or even diabetes, regardless of whether an individual doesn't sleep well. 

    Among a random sample of 16,500 men and women ranging in age from 20 to 100 years old from central Pennsylvania, 8.7 percent had excessive daytime sleepiness. 

    Researchers, who considered a wide range of possible reasons for why these individuals were excessively sleepy during the daytime, found that excessive daytime sleepiness was more strongly associated with depression and obesity or metabolic factors than with sleep-disordered breathing or sleep disruption. 

    Depression was by far the most significant risk factor for excessive daytime sleepiness, they report in the Journal of Clinical Endocrinology and Metabolism. 

    The likelihood of being excessively sleepy during the daytime was more than three times higher in those who reported they were being treated for depression. 

    The investigators also observed strong ties between excessive daytime sleepiness and diabetes. Individuals reporting treatment for diabetes were close to two times more likely to report excessive daytime sleepiness than those who were not being treated for diabetes. 

    Being overweight also increased the likelihood of excessive daytime sleepiness. 

    Excessive daytime sleepiness was more common in people younger than age 30, a finding that hints at the presence of unmet sleep needs and depression, and in the over-75 crowd, suggesting increasing medical illness and health problems, they explain. 

    Smoking also emerged as a risk factor for excessive daytime sleepiness, a link that hasn't been shown before. It could be that smokers use the stimulant effect of nicotine to self-treat their daytime drowsiness, the authors suggest. 

    Sleep apnea -- brief episodes when breathing stops during sleep -- was not a significant player in excessive daytime sleepiness. This is consistent with prior studies that have reported only weak associations between sleep apnea and excessive daytime sleepiness. 

    The authors conclude that adults plagued by excessive daytime sleepiness should be thoroughly evaluated for depression and diabetes, regardless of whether or not sleep-disordered breathing is present. 

    醫yi生sheng們men通tong常chang認ren為wei白bai天tian極ji度du嗜shi睡shui是shi夜ye晚wan睡shui眠mian時shi間jian不bu足zu或huo睡shui眠mian紊wen亂luan造zao成cheng的de。但dan美mei國guo一yi項xiang最zui新xin的de研yan究jiu結jie果guo則ze顯xian示shi
，白bai天tian極ji度du嗜shi睡shui可ke能neng是shi出chu現xian糖tang尿niao病bing或huo抑yi鬱yu症zheng的de征zheng兆zhao。 

    據路透社9月5日報道，美國研究人員在賓夕法尼亞州中部地區隨機調查了1.65萬名年齡在20歲至100歲的男女
，其中8.7％的被調查者曾有過日間極度嗜睡的情況。 

    研究人員在考慮到很多能引起人們日間極度嗜睡的原因後發現
，與睡眠呼吸紊亂或睡眠中斷相比，日間極度嗜睡和抑鬱症

、肥胖或新陳代謝等因素具有更為緊密的聯係。 

    研(yan)究(jiu)人(ren)員(yuan)發(fa)現(xian)，到(dao)目(mu)前(qian)為(wei)止(zhi)，精(jing)神(shen)抑(yi)鬱(yu)是(shi)導(dao)致(zhi)人(ren)們(men)日(ri)間(jian)極(ji)度(du)嗜(shi)睡(shui)最(zui)為(wei)重(zhong)要(yao)的(de)危(wei)險(xian)因(yin)素(su)。在(zai)那(na)些(xie)患(huan)有(you)抑(yi)鬱(yu)症(zheng)的(de)被(bei)調(tiao)查(zha)者(zhe)中(zhong)，出(chu)現(xian)日(ri)間(jian)極(ji)度(du)嗜(shi)睡(shui)的(de)可(ke)能(neng)性(xing)要(yao)比(bi)其(qi)他(ta)人(ren)高(gao)3倍(bei)還(hai)多(duo)。另(ling)外(wai)，糖(tang)尿(niao)病(bing)也(ye)和(he)日(ri)間(jian)極(ji)度(du)嗜(shi)睡(shui)具(ju)有(you)非(fei)常(chang)緊(jin)密(mi)的(de)聯(lian)係(xi)。在(zai)那(na)些(xie)患(huan)有(you)糖(tang)尿(niao)病(bing)的(de)被(bei)調(tiao)查(zha)者(zhe)中(zhong)
，他(ta)們(men)出(chu)現(xian)日(ri)間(jian)極(ji)度(du)嗜(shi)睡(shui)的(de)可(ke)能(neng)性(xing)是(shi)其(qi)他(ta)人(ren)的(de)近(jin)2倍。研究人員還發現，體型肥胖也能增加人們出現日間極度嗜睡的可能性。 

    研究人員同時發現
，日間極度嗜睡症狀在30歲以下的年輕人和75歲以上的老年人中更為常見。研究人員對此解釋說，年輕人出現這種症狀暗示著他們常常睡眠不足或精神抑鬱
；而老年人則是由於逐漸增多的各種疾病和健康問題所致。 

    值(zhi)得(de)一(yi)提(ti)的(de)是(shi)
，睡(shui)眠(mian)呼(hu)吸(xi)暫(zan)停(ting)症(zheng)在(zai)日(ri)間(jian)極(ji)度(du)嗜(shi)睡(shui)中(zhong)扮(ban)演(yan)的(de)角(jiao)色(se)卻(que)並(bing)不(bu)那(na)麼(me)重(zhong)要(yao)。這(zhe)與(yu)先(xian)前(qian)一(yi)個(ge)研(yan)究(jiu)結(jie)果(guo)相(xiang)一(yi)致(zhi)，該(gai)研(yan)究(jiu)認(ren)為(wei)，睡(shui)眠(mian)呼(hu)吸(xi)暫(zan)停(ting)症(zheng)和(he)日(ri)間(jian)極(ji)度(du)嗜(shi)睡(shui)兩(liang)者(zhe)之(zhi)間(jian)具(ju)有(you)的(de)聯(lian)係(xi)非(fei)常(chang)微(wei)弱(ruo)。

    另ling外wai，研yan究jiu人ren員yuan還hai首shou次ci發fa現xian日ri間jian極ji度du嗜shi睡shui和he吸xi煙yan之zhi間jian存cun在zai著zhe某mou種zhong聯lian係xi。研yan究jiu人ren員yuan稱cheng，一yi些xie吸xi煙yan者zhe就jiu是shi利li用yong尼ni古gu丁ding的de刺ci激ji作zuo用yong來lai驅qu散san自zi己ji在zai白bai天tian的de睡shui意yi。