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      • KCI등재

        정신분열병에 대한 리스페리돈의 효과 및 안정성

        이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

        연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

      • 가지의 RAPD 분석을 위한 PCR 최적조건 구명

        최재희,김용철,최인수 밀양대학교 농업기술개발연구소 2000 農業技術開發硏究所報 Vol.4 No.1

        The Purpose of this study was to optimize PCR condition for RAPD analysis in eggplant. 3×3×3 factorial experiment for template DNA concentration, MgCl2 concentration, and amount of taq polymerase was conducted. Another factorial experiment for denature, annealing, extension temperature on the optimal PCR condition was also conducted. The best template DNA concentration was 60ng(0.5unit taq polymerase and 2.5mM MgCl2, 1unit taq polymerase and 2.5mM MgCl2, and 1unit Taq polymerase and 7.0mM MgCl2). Clear bands were observed from 2.5mM, 4.5mM, and 7.0mM of MgCl2 concentration if template DNA concentration and amount of taq polymerase were properly combined. Amount of taq polymerase for the optimal PCR condition was 0.5unit and 1unit when template DNA concentration and MgCl2 concentration were properly combined. When we consider results from template DNA concentration, MgCl2 concentration, and amount of taq polymerase, 3 conditions(60ng of template DNA, 2.5mM MgCl2 and 0.5unit taq polymerase; 60ng of template DNA, 2.5mM MgCl2 and 1unit taq polymerase; and 60ng of template DNA, 7.0mM MgCl2 and 1unit taq polymerase) were best combinations for the optimal PCR condition. Reaction temperatures for the optimal PCR condition were 84℃, 32℃, 62℃; 90℃, 40℃, 72℃; and 92℃, 36℃, 72℃.

      • KCI등재

        조기 발병한 정신증적 장애에서 자기공명영상을 이용한 측뇌실에 대한 구조적인 예비연구

        이윤희,강민희,김철응,이정섭,배재남,홍강의 대한소아청소년정신의학회 2001 소아청소년정신의학 Vol.12 No.2

        연구목적:측뇌실의 확장은 성인기의 정신분열병에서 잘 확립되는 소견이지만, 조기에 발병한 정신증적 장애에서는 아직 논란이 있다. 본 연구에서는 자기공명영상을 이용한 후향적인 방법을 통하여 지금까지 비교적 연구가 많이 시행되지 않았던 조기발병한 정신분열증·양극성 장애 환아들을 대상으로 측뇌실의 구조적인 이상을 연구하여, 이러한 뇌의 구조적 이상이 병의 초기부터 시작되어 정상과는 다른 경과로 진행되는 것인가를 알아보고자 하였다 방법:정신분열병과 양극성 장애의 DSM-Ⅲ-R 진단 기준에 부합하는 14명의 환아(평균 연령 14.0세,표준편차 2.1)와 26명의 두통 대조군에서 뇌자기공명 영상상을 후향적으로 모집하였다. 분석을 위하여 측뇌실이 가장 잘 보이는 축 영상(axial image)를 선택하였다. 뇌자기공명영상상은 평판형 스캐너로 읽어들여서 NIH IMAGE 프로그램을 통하여 분석하였다. 결과:환자군에서는 측뇌실 크기, 측뇌실확장지수가 연령의 증가에 따라 함께 증가하는 상관관계를 나타내었으나, 대조군에서는 연령과 측뇌실 크기, 측뇌실확장지수 등이 유의한 상관관계를 보이지 않았다. 환자군에서는 정상군에서 보이는 좌우 측뇌실 비대칭성이 소실된 결과를 보였다. 그리고 통계적으로 유의한 정도는 아니었으나 환자군이 대조군에 비해 측뇌실과 측뇌실확장지수가 큰 경향을 보였다. 결론:정신증적 환자에서의 뇌의 구조적 이상은 병의 비교적 초기 경과에서부터 시작되며, 정상과는 다소 다른 경과를 취하여 진행한다는 것을 시사하는 결과라 할 수 있다. Objective : The enlargement of the lateral ventricle is well established finding in adult-onset schizophrenia, but in the patients with early-onset psychotic disorder(EOPD) is still controversal. To identify structural abnormalities of the lateral ventricle in patients with EOPD and difference of the brain developmental course in EOPD group, planimetrical assessment of the lateral ventricle was conducted by means of retrospective quantitative neuroimaging. Methods : The brain MR images of 14 patients with EOPD(mean age 14.0±2.1 years) who met the DSM-Ⅲ-R diagnostic criteria for schizophrenia and bipolar disorder and 24 control subjects with simple headache(mean age 10.0±2.1 years) were collected. Single best view for the lateral ventricle, one axial slice was selected for analysis. MR images were redigitalized with flatbed scanner and data were analyzed with NIH IMAGE software. Results : In the patients with EOPD, there were significant correlations between aging and lateral ventricular sizes and between aging and ventricular brain ratio(VBR). The statistical significance of normal asymmetry of the lateral ventricle was not observer for the EOPD group. The EOPD group had larger lateral ventricular sizes and VBR than control group, but these results were not statistically significant. Conclusion : These findings suggest that the brain abnormalities in patients with EOPD progress from the earlier course of the disorders and the course of brain development in EOPD group is different from control group.

      • 신 손상 환자의 고식적 요법에 관한 임상적 고찰

        김희철,전윤수,김민의,이남규,박영호 순천향의학연구소 1996 Journal of Soonchunhyang Medical Science Vol.2 No.2

        Recently according to the increase of the traumatic patient there is a trent for the prevalence of renal injuries to increase. The key point in managing the renal injuries is that we should make decision the treatment plan after accurate diagnosis from clinical symptoms, physical examination, radiologic studies. The goal of the management is the conservation of the renal function. The management of renal injuries by nonoperative or operative methods has been a subject of controversy for more than 2 decades. A aggressive immediated operative approach is generally advocated in some centers, while a more watchful conservative approach is endorsed in others. From January 1985 to May 1995, 159 patients with renal injury had been managed at Soonchunhyang University Hospital. Among 159 patients, 83 patients were classified with minor renal injury and 76 patients major renal injury. The Computerized Tomography was useful in diagnosing stage of injuries and detecting combined injuries which were not detected in excretory urography. All stabilized patients were managed by careful continuous observation, bed rest, appropriate fluid resuscitation and prophylactic antibiotic coverage, but unstabilized patients(17 cases) were managed by immediate operation. Complications occurred in 10 patients with a major renal injury associated with a devascularized fragment but not in other patients. In conclusion, the accurate diagnosis and treatment plan of renal injury with computerized tomography are important to avoid improper treatment. I conclude that conservative management of minor renal injury and major renal injury associated with vascularized fragment is a proper method of treatment. However, early surgical intervention should be considered in patients with major renal injury associated with devascularized fragment because of high complication rate and delayed surgical intervention rate.

      • 저염도 음식물 쓰레기를 이용한 퇴비시여가 배추의 생육에 미치는 영향

        전윤태,박길환,조경철,김희경,지연태,정순주 全南大學校 農業科學技術硏究所 2001 農業科學技術硏究 Vol.36 No.-

        This study was conducted to investigate the changes of physico-chemical properties of soil applied with compost made by food wastes and its effect on the growth and yield of Chinese cabbage. Chinese cabbage was grown in the soil treated with food waste compst(FWC) of 0, 0.625, 1.25, 2.5, 5 and 10㎏/3.3㎡. As the amount of FWC increased, number of leaves, leaf area and fresh weight increased where application of 5㎏ and 10㎏/3.3㎡ showed vigorous plant growth in the late growing period. The pH of soil by application of FWC was not raised, which was similar to the soil before treatment. Organic matter increased in soil by increasing the amount of FWC. However, concentration of Cu and Pb in the soil reduced. The concentration of available phosphate(P) was lower in the soil treated with FWC than in the soil before treatment, which means that a large amount of P may be uptaken by plant. This study suggested that FWC should be an alternative to chemical fertilizer for vegetable production.

      • 음식물 쓰레기 퇴비가 오이 발아와 유묘생장에 미치는 영향

        박진영,조경철,김희경,지연태,정순주 全南大學校 農業科學技術硏究所 2001 農業科學技術硏究 Vol.36 No.-

        This study was conducted to find out toxicity of compost made of food waste to cucumber seed germination and seedlings growth when it was mixed with Mixlite for bed substrate. Mixlite was solely used as bed soil, or mixed with food waste compost ranging 1% to 100% (w/w). Germination percentage and seedling growth of cucumber were examined in 4 weeks after seedling. When cucumber seeds were sowed in Mixlite mixed with food waste compost at 100, 50, 30, 20, 10 or 1%, germination percentages were 30, 36, 38, 46, 74 and 84% compared to with control(100%), respectively. It showed that germination percentage percentage was adversely affected by the amount of food waste composed mixed in the bed substract. Plant height and hypocotyls diameter, root length and root fresh weight, hypocotyls fresh weight and cotyledon fresh weight of cucumber seedling were similarly adversely affected by the amount of food waste compost. Optimum content of the food waste compost for cucumber nursery substrate was found to be 1% of Mixlite.

      • 유제놀에 의한 즉시형 알레르기 반응의 억제

        김상현,신태용,김형룡,이영미,이은희,신보경,김윤철,안년형,김형민 우석대학교 의약품개발연구소 1996 藥學硏究誌 Vol.1 No.-

        The current study evaluates the capacity of eugenol to regulate immediate allergic reaction by control of histamine release. Administrations of eugenol (1 M/kg. i.p.) at 60 min before and 5.10 min after the compound 48/80 treatment (8 mg/kg.i.p.) were shown the mortality rates as 0.44.4. and 77.8%. respectively. A 60 min before administered group revealed a singificant inhibition of serum his-tamine release compared with those of 5 and 10 min after the compound 48/80 injection. Eugenol (6-48mM) was also showed a dose-dependent activity on the compound 48/80-induced histamine release from the highly purified population of Alcian Blue-positive peritoneal mast cells. These results indicate that in vitro treatment with exogenous eugenol inhibited the active response of mast cell populations and modulated its characteristics.

      • SCOPUSKCI등재

        당뇨병 환자에서 혈장 Thrombin-Antithrombin Ⅲ 및 Plasmin-α_2-Plasmin Inhibitor 복합체의 임상적 의의

        김경욱,김은숙,정상수,윤수지,박우일,이준희,남수연,안철우,문병수,김경래,차봉수,송영득,임승길,이현철,허갑범 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.25 No.5

        연구배경:당뇨병 환자에서 혈액응고 및 섬유소용해 체계의 이상경향이 있어 그 결과로 여러 혈관합병증의 발생위험이 높다는 사실은 널리 알려져 있다. 그 기전은 아직 확실히 밝혀지지 않았으나, 고혈당으로 인한 혈장 단백질들의 비효소성 당화작용이나 산화성 스트레스로 인한 유리 라티칼 작용으로 응고항진이나 섬유소용해 활성의 저하를 유발하는 것으로 생각되고 있다. 최근 응고 및 용해인자와 그 억제자의 복합체들의 증가가 이 상태를 비교적 예민하게 반영한다고 알려져 있다. 방법:본 연구에서는 당뇨병 환자 101명과 정상 대조군 20명에서 혈장내 thrombin­antithrombin complex(TAT)와 plasmin­α₂­plasmin inhibitor complex(PIC)를 측정하여 비교하고, 당뇨병 환자에서 미세혈관 합병증과 대혈관합병증의 유무에 따른 차이와, 이미 혈관 질환의 위험인자로 알려져 있는 인자들간의 상관성을 알아보고자 하였다. 결과:1. 환자의 분포를 살펴보면 혈관합병증이 있는 군은 85명, 혈관합병증이 없는 군은 16명이었고, 평균연령은 각각 57.9±14.1세, 49.9±16.6세로 혈관 합병증이 있는 군에서 더 나이가 많았고, 체질량지수는 23.2±3.4㎏/㎡, 24.1±3.4㎏/㎡로 두 군간 유의한 차이는 없었다. 또 두 군간의 혈압 및 HbA1c, 공복혈당 및 인슐린과 C­peptide, 총 콜레스테롤, 중성지방, HDL­콜레스테롤, Lp⒜는 유의한 차이가 없었고, 미세혈관합병증이 있는 군에서 당뇨병의 유병기간이 길었다. 2. TAT 및 PIC의 농도는 정상 대조군에서는 2.8±1.2 ng/mL, 240.4±69.7 ng/mL이었고, 당뇨병 환자군에서는 9.5±22.6 ng/mL, 472.2±258.7 ng/mL이었다. TAT와 PIC 모두 당뇨병 환자군에서 정상 대조군에 비해 유의하게 증가되어 있었고(p<0.001), TAT/PIC ratio는 두 군간 차이가 없었다. 3. 당뇨병 환자의 혈관합병증에 따른 TAT 및 PIC, fibrinogen 농도는 합병증이 없는 군은 각각 4.1±2.4ng/mL, 362.2±272.0ng/mL, 322.7±102.4mg/mL으로 PIC와 fibrinogen의 증가를 보였으나, 연령을 보정한 후에는 통계학적 유의성은 없었다. 또 대혈관 합병증군에서는 각각 6.0±4.9 ng/mL, 507.4±321.6 ng/mL, 427.1±194.7 mg/dL이었으며 미세·대혈관 합병증군에서는 10.4±6.4 ng/mL, 484.8±269.7 ng/mL, 388.4±132.4 mg/dL으로 TAT의 증가를 보였으나 역시 연령을 보정한 후에는 통계학적 유의성은 없었다. 4. 미세혈관합병증군에서 HbA1c(>8%)가 높은 군의 PIC 농도가 유의하게 높았고(p=0.049), 대혈관합병증군에서 HbA1c(>8%)가 높은 군의 총 콜레스테롤 농도가 유의하게 높았다(p=0.042). 5. 총 당뇨병 환자군에서 PIC는 fibrinogen과 HbA1c와 양의 상관관계를, BMI와 음의 상관관계를 보였으며(r=0.47, 0.31,-0.25), 혈관 합병증이 없는 당뇨병 환자군에서만 TAT는 HbA1c와 양의 상관관계를 보였다(r=0.67). 결론:이상의 결과에서 혈장 TAT 및 PIC 농도는 당뇨병 환자에서 정상 대조군에 비해 의미있게 증가되어 있었고, 당뇨병 환자군에서는 연령의 증가와 유병기간이 혈액응고항진 및 용해의 장애에 큰 역할을 함을 알 수 있었으며, 총 당뇨병 환자군에 PIC와 HbA1c와 양의 상관관계를, BMI와 음의 상관관계를 보였으며 혈관 합병증이 없는 당뇨병 환자군에서만 TAT는 HbA1c와 양의 상관관계를 보였다. 따라서 당뇨병 환자에서 혈액응고 및 용해의 장애가 동반되어 있다고 볼 수 있으며, 혈장 TAT 및 PIC는 혈관합병증으로의 진행을 예측하는 지표로서 유용하리라 생각된다. 또 혈당조절정도와 상관성이 있으므로 혈당조절후에 추적검사를 시행하여 합병증의 예방이 가능한지 추후 연구가 필요하리라 생각된다. Background : Abnormality of coagulation and fibrinolystic system is known as a predisposing factor of vascular complication in diabetes. Although the pathogenesis is not well known, non-enzymatic glycation reaction and the increase in production of free radicals due to an increased oxidative stress may be linked to the hypercoagulibility and hypofibrinolytic activity. As indices of abnormality in coagulation and firinolysis in peripheral blood, plasma thrombin-antithrombin Ⅲ complex (TAT) and plasmin-α_2-plasmin inhibitor complex (PIC) were measured. The purpose of this study was to clarify whether hypercoagulability exists in diabetic patients with or without vascular complication. Methods : In our study, we measured plasma thrombin-antithrombin Ⅲ compelx (TAT) and plasmin-α_2-plasmin inhibit or complex (PIC) in 101 diabetic subjects and 20 controls. Comparing TAT and PIC levels in diabetic microvascular complication group, diabetic macrovascular complication group and controls, we examined correlation between risk factors associated with diabetic vascular complication. Results : 1. The group with diabetic vascular complication was older than group without complication. There was no significant difference in BMI, blood pressure, HbA_ic, blood sugar level, insulin, C-peptide, serum creatinine, total cholesterol, triglyceride, HDL-cholesterol, Lp (a) between two groups. The group with diabetic microvascular complication had longer duration of diabetes. 2. Concentration of TAT and PIC were 2.8±1.2 ng/ mL, 240.4±69.7 ng/ mL in controls and 9.5±22.6 ng/ mL, 472.2±258.7 ng/ mL in diabetic patients, respectively. TAT and PIC were significantly higher in diabetic patients than in control (p<0.001). But TAT/PIC ratio was no significant difference between two groups. 3. In diabetic patients, concentration of TAT and PIC and fibrinogen were respectively 4.1±2.4 ng/ mL, 362.2±272.0 ng/ mL, 322.7±102.4 mg/ dL in group without vascular complication and 5.3±4.1 ng/ mL, 529.5±258.7 ng/ mL, 374.9±106.2 mg/ dL in group with microvascular complication, which group had increase in PIC and Fibrinogen but no significance after correction of age. Concentration of TAT and PIC and Fibrinogen were 60.±4.9 ng/ mL, 507.4±321.6 ng/ mL, 427.1±194.7 mg/ dL in macrovascular complication, and 10.4±6.7 mg/ mL, 484.8±269.7 ng/ mL, 388.4±132.4 mg/ dL in combined vascular complication which group showed increase of TAT but also had no significant increase after correction of age. 4. In diabetic microvascular complication patients, group of high HbA_1c (>8%) (p=0.049) had significant high PIC concentration. In diabetic macrovascular complication patients, group of high HbA_1c (>8%) (p=0.042) had significant high total cholesterol concentration. 5. In all diabetic patients, PIC was positively correlated with fibrinogen and HbA_1c and negatively correlated BMI (r=0.47, 0.31, -0.25). Only in daibetic patients without angiopathy, TAT was positively correlated with HbA_1c (r=0.67). Conclusion : In this study, plasma TAT and PIC concentration significantly increased in diabetic patients compared with controls, and PIC was increased in group with microvascular complication, TAT were increased in group with combined micro macrovascular complication. However, there was no significance relationship existed when correctinf for age. PIC was correlated with HbA_1c. TAT was correlated with HbA_1c only in the group without angiopathy. Abnormality of coagulation and fibrinolysis were combined in diabetes, plasma TAT and PIC can be used as an index of vascular complication. Also we found the correlation with the degree of the blood glucose control. Therefore we need follow up study for the possibility of prevention of vascular complication after controlling the blood glucose to age-matched patients (J Kor Diaabetes Asso 25:354~363, 2001).

      • KCI등재

        균열을 내재한 저압터빈 최종단 블레이드의 진동 특성 및 파괴 임계균열길이 해석

        윤희철(Hee-Chul Youn),우창기(Chang-Ki Woo),이장규(Zhang-Kyu Rhee) 한국생산제조학회 2016 한국생산제조학회지 Vol.25 No.5

        The sizes of last stage blades (LSB) in a low-pressure steam turbine have been getting larger for the development of high-capacity power plants. They are also larger than other blades in the same system. As a result, crack propagation in an LSB is caused by the large centrifugal force, low natural frequency, and repeated turbine startups. In this study, the critical crack length for a fracture and vibration characteristics, in accordance with crack propagation, were analyzed using a finite element method to calculate the stress intensity factor (SIF) and the natural frequency that was affected by the stress-stiffening effect. It was calculated that the frequency of the third and fifth modes passed the excited harmonic resonance (5X and 10X) and the observed calculated critical crack length matched that of the real fractured surface.

      • SCISCIESCOPUS

        Air Pollution and Symptoms of Depression in Elderly Adults

        Lim, Youn-Hee,Kim, Ho,Kim, Jin Hee,Bae, Sanghyuk,Park, Hye Yin,Hong, Yun-Chul National Institute of Environmental Health Science 2012 Environmental health perspectives Vol.120 No.7

        <P>Background: Although the effect of air pollution on various diseases has been extensively investigated, few studies have examined its effect on depression.</P><P>Objectives: We investigated the effect of air pollution on symptoms of depression in an elderly population.</P><P>Methods: We enrolled 537 participants in the study who regularly visited a community center for the elderly located in Seoul, Korea. The Korean version of the Geriatric Depression Scale-Short Form (SGDS-K) was used to evaluate depressive symptomatology during a 3-year follow-up study. We associated ambient air pollutants with SGDS-K results using generalized estimating equations (GEE). We also conducted a factor analysis with items on the SGDS-K to determine which symptoms were associated with air pollution.</P><P>Results: SGDS-K scores were positively associated with interquartile range (IQR) increases in the 3-day moving average concentration of particulate matter with an aerodynamic diameter ≤ 10 μm (PM<SUB>10</SUB>) [17.0% increase in SGDS-K score, 95% confidence interval (CI): 4.9%, 30.5%], the 0–7 day moving average of nitrogen dioxide [NO<SUB>2</SUB>; 32.8% (95% CI: 12.6%, 56.6%)], and the 3-day moving average of ozone [O<SUB>3</SUB>; 43.7% (95% CI: 11.5%, 85.2%)]. For these three pollutants, factor analysis showed that air pollution was more strongly associated with emotional symptoms such as feeling happy and satisfied than with somatic or affective symptoms.</P><P>Conclusions: Our study suggests that increases in PM<SUB>10</SUB>, NO<SUB>2</SUB>, and O<SUB>3</SUB> may increase depressive symptoms among the elderly. Of the symptoms evaluated, ambient air pollution was most strongly associated with emotional symptoms.</P>

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