An open-label, rater-blinded, 8-week trial of bupropion hydrochloride extended-release in patients with major depressive disorder with atypical features.

The present study aimed at investigating the effectiveness and tolerability of -bupropion hydrochloride extended release (XL) in major depressive disorder (MDD) patients with atypical features (AF).51 patients were prescribed bupropion XL for 8 weeks (6 visits: screening, baseline, weeks 1, 2, 4 and 8). The primary efficacy measure was a change of the Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorder Version (SIGH-SAD) from baseline to endpoint. Secondary efficacy measures included the SIGH-SAD atypical symptoms subscale, Clinical Global Impression-Severity (CGI-S), Sheehan Disability Scale (SDS) and Epworth Sleepiness Questionnaire (ESQ). Response or remission was defined as ≥50% reduction or ≤7 in SIGH-SAD total scores, respectively, at end of treatment.The HAM-D-29 total score reduced by 55.3% from baseline (27.3±6.5) to end of treatment (12.2±6.3) (p<0.001). Atypical symptom subscale scores also reduced by 54.5% from baseline (9.2±3.0) to end of treatment (4.2±2.8) (p<0.001). At the end of treatment, 24.4% (n=10) and 51.2% (n=21) subjects were classified as remitters and responders, respectively. The most frequently reported AEs were headache (13.7%), dry mouth (11.8%), dizziness (9.8%), and dyspepsia (9.8%).Our preliminary study indicates that bupropion XL may be beneficial in the treatment of MDD with atypical features. Adequately powered, randomized, double-blind, placebo-controlled trials are necessary to determine our results.

Validation of limited lymphadenectomy for lower-third gastric cancer based on depth of tumour invasion.

BACKGROUND: This study aimed to determine the appropriate extent of lymph node (LN) dissection in gastric cancer by analysing LN metastasis patterns from prospectively collected topographical data on nodal status at Seoul National University Hospital, Korea. METHODS: The metastasis rate for each LN station was analysed according to the depth of tumour invasion in patients with primary lower-third gastric cancer who underwent curative gastrectomy. The Maruyama Index of unresected disease (MI) was calculated using the WinEstimate(®) program with simulation of various extents of LN dissection. RESULTS: LN metastasis in mucosal cancer was rare; 2·6 per cent of patients had a MI of more than 5 with simulation of D1 plus station 7 dissection, whereas 0·9 per cent had a MI above 5 with D1 plus stations 7 and 8a. In submucosal cancer, 3·3 per cent of tumours metastasized to level 2 LN stations outside the range of D1 plus stations 7, 8a and 9. The proportion of patients with a MI above 5 was 9·0 per cent with D1 plus stations 7, 8a and 9 dissection. The nodal metastasis rate was higher at level 1 and 2 for muscularis propria or deeper cancers. CONCLUSION: D1 dissection plus stations 7 and 8a for mucosal cancer, and D2 dissection for cancers of the muscularis propria or deeper seems appropriate. For submucosal cancer, an expanded dissection to the D2 level should be considered to ensure complete removal of metastatic LNs.

Changes in clinicopathological features and survival after gastrectomy for gastric cancer over a 20-year period.

BACKGROUND: The pattern of gastric cancer in the Western world is changing, with an increased proportion of tumours in the upper stomach. The aim of this study was to investigate changes in clinicopathological features and survival of patients with resected gastric cancer at a single institution, in an area of high incidence in the Far East. METHODS: Clinical features and pathological findings were compared in patients with gastric cancer who underwent gastrectomy at Seoul National University Hospital during four consecutive periods (1986-1990, 1991-1995, 1996-2000 and 2001-2006). RESULTS: There were 12 026 patients. The mean age increased from 53·4 years in the first period to 57·4 years in the last (P < 0·001). The proportion of patients aged 70 years or older also increased, reaching 16·1 per cent in the final period. Upper-third cancer increased from 5·3 per cent in the first period to 14·0 per cent in the fourth (P < 0·001). Early gastric cancer (pathological T1) increased continuously over the four time intervals, from 24·8 to 48·9 per cent (P < 0·001). The overall 5-year survival rate increased from 64·0 per cent in the first period to 73·2 per cent at the end (P < 0·001), and this survival improvement was apparent in patients aged 40 years or more. CONCLUSION: The mean age of patients with gastric cancer has increased during the past 20 years. The proportion of early gastric cancer and overall survival have gradually increased, especially in patients aged over 40 years.

Progression to insulin deficiency in Korean patients with Type 2 diabetes mellitus positive for anti-GAD antibody.

AIMS: To investigate the rate of progression to insulin deficiency in Korean patients with Type 2 diabetes mellitus positive for anti-GAD antibody (GADA) and to determine the factors related to progression to insulin deficiency. METHODS: We retrospectively analysed data on 87 GADA-positive and 87 age- and sex-matched GADA-negative patients with Type 2 diabetes. GADA-positive patients were further subclassified into high-titre (≥ 250 WHO units/ml) (n = 24) and low-titre (< 250 WHO units/ml) (n = 63) subgroups. Cox proportional hazard analysis was used to identify factors associated with progression to insulin deficiency. RESULTS: Over a period of 6 years, two of 87 (2.3%) GADA-negative and 37 of 87 (42.5%) GADA-positive patients had progressed to insulin deficiency. The rate of progression to insulin deficiency was higher in the high-titre than in the low-titre subgroup (75.0 vs. 30.2%). Multivariate analysis in GADA-positive patients showed that high-titre GADA and low BMI at diagnosis were independent factors significantly related to progression to insulin deficiency. CONCLUSIONS: The presence of GADA predicted the progression to insulin deficiency in Korean patients with Type 2 diabetes. In GADA-positive patients, high-titre GADA and low BMI were associated with this progression.

Biomarker analysis in stage III-IV (M0) gastric cancer patients who received curative surgery followed by adjuvant 5-fluorouracil and cisplatin chemotherapy: epidermal growth factor receptor (EGFR) associated with favourable survival.

The aim of this study was to analyse the impact of epidermal growth factor receptor (EGFR), thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), thymidine phosphorylase (TP), aurora kinase (ARK) A/B, and excision repair cross-complementing gene 1 (ERCC1) on the efficacy of adjuvant chemotherapy with 5-fluorouracil and cisplatin (FP) after curative gastric resection. Normal and cancer tissue were separately obtained from gastrectomy samples of 153 patients with AJCC stage III-IV (M0) who subsequently treated with adjuvant FP chemotherapy. TS, DPD, TP, ERCC1, and ARK proteins were measured by immunohistochemistry (IHC). EGFR expression was investigated using a standardized IHC with the EGFR PharmDx assay. Amplification of EGFR gene was analysed using fluorescent in situ hybridisation (FISH). In multivariate analysis, stage, ratio of positive to removed lymph nodes, and EGFR expression were significant prognostic factors for overall survival. Patients with higher EGFR expression had better overall survival than those with lower expression (relative risk: 0.475 (95% confidence interval, 0.282-0.791, P=0.005). Low EGFR expression might be a predictive marker for relapse in curative resected stage III-IV (M0) gastric cancer patients who received adjuvant FP chemotherapy.

Safety of extended endoscopic mucosal resection and endoscopic submucosal dissection following the Japanese Gastric Cancer Association treatment guidelines.

BACKGROUND: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are widely performed. Indications for these procedures have been extended in Korea and Japan. The aim was to evaluate whether these extended indications are safe. METHODS: All patients who had surgery for early gastric cancer at Seoul National University Bundang Hospital between May 2003 and December 2007 were identified from a prospective database. Lymph node status was examined in patients who met extended indications for EMR and had undergone surgical resection. RESULTS: Of patients with mucosal cancers, 129 met extended indications for EMR or ESD and three (2.3 per cent) had lymph node metastasis. Of the 52 submucosal cancers meeting extended indications for EMR or ESD, two (4 per cent) had lymph node metastasis. Differentiated mucosal cancers without ulcer formation did not have lymph node metastasis, irrespective of size. CONCLUSION: Extending the indications for EMR and ESD according to the Japanese Gastric Cancer Association guidelines carries an increased risk of lymph node metastasis. For cancers meeting these criteria, treatment by gastric resection with lymph node dissection should still be considered. A well differentiated mucosal cancer of any size without ulceration may be considered as an extended indication for EMR or ESD.

Fatty liver is an independent risk factor for the development of Type 2 diabetes in Korean adults.

AIMS: To investigate whether fatty liver per se is an independent risk factor of incident type 2 diabetes mellitus (T2DM) in Koreans. METHODS: We examined the clinical and laboratory data of 5372 non-diabetic participants (3670 men and 1702 women; age 46.8 +/- 8.4 years, range 20-79 years) who underwent voluntary medical check-ups in 2000 and follow-up examinations in 2005. RESULTS: Two hundred and thirty-three participants (4.3%) developed T2DM after 5 years. Univariate analysis showed that the development of diabetes was associated with: male sex; family history of diabetes; smoking; older age; higher body mass index (BMI), systolic and diastolic blood pressure, fasting plasma glucose (FPG), hepatic enzymes, total cholesterol and triglycerides; lower HDL cholesterol; and the presence of fatty liver on ultrasonography at baseline. In multiple logistic regression models, after adjusting for age, sex and alcohol consumption, patients with fatty liver were at significantly higher risk of developing T2DM compared to those without fatty liver [relative risk (RR) 3.92, 95% confidence interval (CI) 2.89-5.31]. After further adjustment for smoking, BMI, triglycerides, HDL cholesterol, FPG, alanine aminotransferase and ultrasonographer, fatty liver remained significantly associated with the development of T2DM (RR 1.51, 95% CI 1.04-2.20). Patients with moderate to severe fatty liver had higher risk ratios than patients with mild fatty liver. Exclusion of frequent drinkers did not attenuate the association. CONCLUSIONS: Fatty liver on ultrasonography is associated with the development of T2DM, independently of classical risk factors, in Korean adults.

Laparoscopic hepatectomy for a modified right graft in adult-to-adult living donor liver transplantation.

BACKGROUND: We performed a modified right hepatectomy completely by laparoscopic techniques preserving the middle hepatic vein (MHV) branches in adult-to-adult living donor liver transplantation (LDLT). PATIENTS AND METHODS: Two young women (24 and 25 years old) volunteered to be live donors for their parents who had hepatocellular carcinomas. As the donors expressed concerns about scarring, we performed a laparoscopic procedure using a hand port device. Mobilization of the right liver and the hepatic parenchymal transection were performed under pneumoperitoneum. Parenchymal transection was performed using a laparoscopic ultrasonic aspirator without the Pringle maneuver. During parenchymal transection, major MHV branches >5 mm were preserved using Hem-o-lock clips. The graft was extracted through the hand port site. On the back table, the 3 MHV branches were reconstructed using an artificial vascular graft. The livers were transplanted without complications. RESULTS: The operative times for the donors were 765 and 898 minutes. The donors did not require transfusions or reoperation; they were discharged on postoperative days 10 and 14 with normal liver functions. CONCLUSION: A hepatectomy performed completely by laparoscopic techniques for a right graft with preservation of the MHV branches was technically feasible.

Brain activation by visual erotic stimuli in healthy middle aged males.

The objective of the present study was to identify brain centers, whose activity changes are related to erotic visual stimuli in healthy, heterosexual, middle aged males. Ten heterosexual, right-handed males with normal sexual function were entered into the present study (mean age 52 years, range 46-55). All potential subjects were screened over 1 h interview, and were encouraged to fill out questionnaires including the Brief Male Sexual Function Inventory. All subjects with a history of sexual arousal disorder or erectile dysfunction were excluded. We performed functional brain magnetic resonance imaging (fMRI) in male volunteers when an alternatively combined erotic and nonerotic film was played for 14 min and 9 s. The major areas of activation associated with sexual arousal to visual stimuli were occipitotemporal area, anterior cingulate gyrus, insula, orbitofrontal cortex, caudate nucleus. However, hypothalamus and thalamus were not activated. We suggest that the nonactivation of hypothalamus and thalamus in middle aged males may be responsible for the lesser physiological arousal in response to the erotic visual stimuli.

Sentinel node biopsy for cT1 and cT2a gastric cancer.

AIMS: To evaluate the feasibility and accuracy of sentinel node (SN) biopsy for gastric cancer. PATIENTS AND METHODS: One hundred patients with gastric cancer diagnosed as cT1 (n=80) or cT2a (n=20) were enrolled. Indocyanine green-stained SNs were analysed by hematoxylin and eosin staining (n=100) and by cytokeratin immunohistochemistry (n=50). RESULTS: SNs were identified in 94 of the 100 patients and the mean number of SNs was 4.4 (range, 1-12). Of these 94 patients, 14 patients had lymph node metastases. Two patients with T1 and one patient with T2 had metastases in non-SNs alone by hematoxylin and eosin staining (diagnostic accuracy =97.3% in T1 and 95.0% in T2). All three patients with a false negative result had a tumour, which was more than 4 cm in size and signet ring cell histology. In two of them, the tumour was located at lesser curvature. By immunohistochemical staining, three patients with T1 and one patient with T2 were found to have lymph node micrometastases in non-SNs alone among 45 patients (diagnostic accuracy =92.1% in T1, 85.7% in T2). CONCLUSION: SN biopsy using indocyanine green can be performed rapidly and easily with a high detection rate and accuracy in patients with T1 gastric cancer. However, it should be performed with caution for large tumours with a signet ring cell histology located at lesser curvature due to the possibility of a false negative result.

Family history of diabetes and the risk of subclinical atherosclerosis.

AIM: This study investigated the influence of a family history of diabetes on the risk of subclinical coronary atherosclerosis according to coronary computed tomography angiography (CCTA) in asymptomatic individuals. METHODS: A total of 6434 consecutive asymptomatic individuals with no prior history of coronary artery disease voluntarily underwent CCTA evaluation as part of a general health examination. Coronary atherosclerotic plaque and significant coronary artery stenosis (degree of stenosis ≥50%) on CCTA were assessed. Logistic regression analysis was used to determine the association between a family history of diabetes and atherosclerotic plaque or significant coronary artery stenosis according to the degree of diabetes (normal, prediabetic and diabetic). RESULTS: Mean age of study participants was 53.7±7.6 years, and 4694 (73.0%) were male. A total of 1593 (24.8%) participants had a family history of diabetes in a first-degree relative. Among the study participants, 1115 (17.3%), 3122 (48.5%) and 2197 (34.1%) were categorized as diabetic, prediabetic and normal, respectively. In diabetic participants, after stepwise adjustments for clinical and laboratory variables, a family history of diabetes was significantly associated with non-calcified plaque (P<0.05 for all), but did not appear to be associated with either calcified or mixed plaques or with significant coronary artery stenosis (P>0.05 for all). In prediabetic and normal participants, a family history of diabetes was not associated with either atherosclerotic plaque or significant coronary artery stenosis (P>0.05 for all). CONCLUSION: In asymptomatic diabetic individuals, a family history of diabetes is consistently associated with non-calcified coronary plaque after adjusting for risk factors.

Nitric oxide produced by macrophages mediates suppression of ConA-induced proliferative responses of splenic leukocytes in the diabetes-prone BB rat.

Splenic cells from the diabetes-prone BB rat show reduced proliferative responses to concanavalin A (ConA) and other mitogens. This study was undertaken to test whether this reduced lymphoproliferation in the BB rat is mediated by an increased production of nitric oxide (NO) by macrophages. Splenic leukocytes from diabetes-prone BB rats and five strains of control rats (BB-R, Wistar-Furth, Sprague-Dawley, Wistar, and Lewis) were cultured in RPMI-1640 media containing ConA. The leukocytes from BB rats showed reduced [3H]thymidine uptake and increased release of NO compared with the control rats. Partial depletion of macrophages from the culture or incubation with -NG-monomethylarginine (NGMMA), a specific NO synthase inhibitor, markedly augmented ConA-induced proliferation of the splenic leukocytes from BB but not the control rats. Enrichment of BB rat macrophages suppressed the proliferation of BB-R rat spleen cells. Excess L-arginine added to the culture reversed the NGMMA effect. These results suggest that increased production of NO by macrophages is partly responsible for the reduced proliferative responses of splenic leukocytes in the BB rat.

Evidence for initial involvement of macrophage in development of insulitis in NOD mice.

Macrophages have been shown to be the major population of infiltrated immunocytes at the early stage of insulitis in diabetes-prone BB rats. This study was undertaken to investigate the role of macrophages in the development of insulitis in nonobese diabetic (NOD) mice. Administration of cyclophosphamide to NOD mice resulted in a significant increase in the incidence of overt diabetes and severity of insulitis compared with that in untreated NOD mice. Intraperitoneal injections of silica completely prevented the development of diabetes and insulitis in both cyclophosphamide-treated and untreated animals. Because silica is selectively toxic to macrophages, the results suggest that macrophages play an important role in the initiation of insulitis in NOD mice.

Studies on autoimmunity for initiation of beta-cell destruction. VII. Evidence for antigenic changes on beta-cells leading to autoimmune destruction of beta-cells in BB rats.

The diabetic syndrome in BioBreeding (BB) rats is believed to result from the destruction of beta-cells by autoimmune responses. However, the initial events that cause the autoimmune destruction of beta-cells remain largely unknown. This investigation was initiated to see whether there are any antigenic changes on the beta-cells from neonatal to adult BB rats that may lead to the autoimmune destruction of beta-cells. Pancreatic grafts from neonatal BB rats remained largely intact without insulitis when transplanted into the renal subcapsular space of acutely diabetic BB rats. Similarly transplanted islet grafts from neonatal BB rats were also not subject to autoimmune destruction. In contrast, islet grafts obtained from adult BB rats, which had been treated with silica to prevent insulitis, were rapidly destroyed in diabetic recipients. These results indicate that beta-cells from neonatal BB rats are different from beta-cells from adult BB rats, at least regarding their recognition by immunologic effectors. Considering our observations and previous information on the initial role of macrophages/dendritic cells in the development of insulitis in BB rats, we suggest that beta-cell-specific antigenic changes that precede insulitis may result in the autoimmune destruction of beta-cells in BB rats.

Preferential infiltration of macrophages during early stages of insulitis in diabetes-prone BB rats.

The subpopulation of lymphoid cells at the different stages of insulitis in BB rats was determined by immunohistochemical techniques with various monoclonal antibodies, including the recently developed OX41, which distinguishes macrophages from T-lymphocytes, OX19 for pan-T-lymphocytes, W3/25 for both helper T-lymphocytes and macrophages, OX8 for cytotoxic T-lymphocytes and natural killer cells, and OX12 for B-lymphocytes. The major population of infiltrated cells found during the early stages of insulitis appeared to be macrophages. This preceded invasion by a mixed population of cells, including both T- and B-lymphocytes and/or natural killer cells. The preferential infiltration of macrophages during the early stages of insulitis strongly suggested that there might be an initial change in the target beta-cells that precedes their immune destruction, although the amplification of immune response by activated T-lymphocytes and natural killer cells at a later stage seemed to be required for the clinical expression of the disease.

Intraoperative gastroscopy for gastric surgery.

BACKGROUND: Few reports are available on the use of intraoperative gastroscopy for gastric surgery. METHODS: The details of 33 patients (25 early gastric cancers and eight gastric submucosal tumors) who underwent intraoperative gastroscopy from June 2003 to June 2004 were analyzed. The type of operation or resection margin was determined by evaluating both sides of the stomach simultaneously by combined operative and gastroscopic methods. RESULTS: Preoperative endoscopic clipping was done preferentially for early gastric cancer. However, when precise localization was needed, intraoperative gastroscopy was used. Curative gastric resection was possible in 25 early gastric cancer patients after accurate lesion localization. Laparoscopic wedge resections of submucosal tumors were performed in seven patients without stenosis by combined laparoscopic and gastroscopic methods. CONCLUSIONS: Intraoperative gastroscopy can be used effectively during gastric surgery for early gastric cancer or submucosal tumors and can be regarded as a modern stethoscope to gastric surgeons.

Prevalence and associated features of albuminuria in Koreans with NIDDM.

OBJECTIVE: To determine the prevalence and the associated features of microalbuminuria and overt proteinuria in Korean subjects with non-insulin-dependent diabetes mellitus (NIDDM) attending a hospital clinic. RESEARCH DESIGN AND METHODS: A total of 631 Korean outpatients with NIDDM were studied cross-sectionally for the presence of albuminuria and other micro- and macrovascular complications. Urinary albumin excretion rate (AER) was determined in timed overnight urine samples. Subjects were divided into three groups: no nephropathy (AER < 20 micrograms/min), microalbuminuria (AER 20-200 micrograms/min), and overt proteinuria (AER > 200 micrograms/min). RESULTS: Increased AER was present in 34% of our patients: 20% had microalbuminuria and 14% had overt proteinuria. Of patients with diabetes duration > or = 15 years, 35% had overt proteinuria. Most (82%) patients with overt proteinuria had retinopathy. Although the prevalence of microalbuminuria as a whole did not differ according to diabetes duration, the prevalence of microalbuminuria in the patients with retinopathy increased with diabetes duration. The microalbuminuric patients without retinopathy (diabetes duration < 5 years) were characterized by higher prevalence of hypertension and previous obesity, higher plasma triglyceride level, and lower plasma high-density lipoprotein cholesterol level. CONCLUSIONS: The prevalence of overt proteinuria in Korean NIDDM patients with a long diabetes duration was higher than that reported in Caucasians. Our data also suggest that the clinical meaning of microalbuminuria may be different based on the presence or the absence of retinopathy. Microalbuminuria in patients with retinopathy most probably would reflect diabetic nephropathy. In contrast, some recent-onset NIDDM patients with microalbuminuria in the absence of retinopathy had features of syndrome X.

High serum lipoprotein(a) levels in Korean type 2 diabetic patients with proliferative diabetic retinopathy.

OBJECTIVE: To examine the possible association between serum lipoprotein(a) [Lp(a)] concentration and proliferative diabetic retinopathy (PDR) in Korean patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: A total of 412 Korean outpatients with type 2 diabetes were examined. Diabetic retinopathy was determined by an ophthalmologist using fundoscopic examination. Serum Lp(a) levels were measured by two-site sandwich enzyme-linked immunosorbent assay. RESULTS: The patients with PDR had higher serum Lp(a) levels than those with no diabetic retinopathy or with nonproliferative diabetic retinopathy (NPDR). Multiple logistic regression analysis showed that high serum Lp(a) levels and the presence of diabetic nephropathy were independent variables having a statistically significant association with PDR. CONCLUSIONS: Korean type 2 diabetic patients with PDR had higher serum Lp(a) levels versus those with no diabetic retinopathy or with NPDR. Although these results suggest that Lp(a) might play a role in the occlusion of retinal capillaries leading to PDR, further prospective studies are required to prove the causal relationship.

Incidence and determinants of microalbuminuria in Koreans with type 2 diabetes.

OBJECTIVE: The incidence of diabetic nephropathy in type 2 diabetes differs widely by race. Although clinical proteinuria is reportedly more common in East Asian type 2 diabetic patients than in their Caucasian counterparts, data on the incidence of microalbuminuria are not available. This study was undertaken to investigate the incidence and the determinants of microalbuminuria in Korean type 2 diabetic patients. RESEARCH DESIGN AND METHODS: A cohort of 188 Korean type 2 diabetic patients with initial normoalbuminuria were followed prospectively for 5.5 +/- 0.9 years in an outpatient clinic of a university hospital. The incidence of elevated urinary albumin excretion (UAE) (> 20 micrograms/min) and its relationship with baseline characteristics and follow-up data were determined. RESULTS: Of the 146 patients who finished the study, 37 showed persistently elevated UAE during follow-up, giving an incidence of 52/1,000 person-years. Age, duration of diabetes, and baseline UAE were significantly higher in the progressors than in the nonprogressors. More patients in the progressor group had retinopathy at baseline and at the end of follow-up. The mean values of fasting plasma glucose, HbA1, and systolic and diastolic blood pressure during the follow-up period were significantly higher in the progressors than in the nonprogressors. Cox proportional hazards analysis revealed that presence of retinopathy, duration of diabetes, mean fasting plasma glucose, and mean systolic blood pressure during follow-up are independent variables that have a statistically significant influence on the development of microalbuminuria. CONCLUSIONS: The incidence of microalbuminuria in Korean type 2 diabetic patients is lower than that reported in Pima Indians with type 2 diabetes but is as high as that in Caucasians with type 1 diabetes. Presence of diabetic retinopathy, poor glycemic control, and high blood pressure are risk factors for development of microalbuminuria in Koreans with type 2 diabetes.

Development and progression of diabetic retinopathy in Koreans with NIDDM.

OBJECTIVE: To determine the incidence and risk factors for the development and progression of diabetic retinopathy in Korean patients with NIDDM. RESEARCH DESIGN AND METHODS: A total of 186 patients with NIDDM who did not have proliferative diabetic retinopathy (PDR) at baseline were prospectively studied for 5.3 +/- 1.0 years in an outpatient clinic of a university hospital. The incidence and progression of diabetic retinopathy was determined by annual funduscopic examination by an ophthalmologist. RESULTS: Of the 130 patients who were free of diabetic retinopathy at baseline, 30 developed it, giving an incidence of 44.4/1,000 person-years. Age and known duration of diabetes, mean fasting plasma glucose, and HbA1 levels during the follow-up period were higher in the patients who developed diabetic retinopathy. Of the 56 patients who had nonproliferative diabetic retinopathy at baseline, 11 developed PDR, giving an incidence of 37.5/1,000 person-years. The patients who progressed to PDR during follow-up (progressors) had a higher change of BMI and urinary albumin excretion rate at baseline and a higher mean HbA1 during the follow-up period than the nonprogressors. Cox proportional hazards analysis revealed that mean HbA1 was the only independent risk factor for both the development and progression of diabetic retinopathy. CONCLUSIONS: The incidence of PDR in Korean NIDDM patients is comparable to that reported in other populations. Poor glycemic control is the most important risk factor for both the development and progression of diabetic retinopathy in NIDDM patients.