Stimulated Salivary Cortisol as a Noninvasive Diagnostic Tool for Adrenal Insufficiency

Background@#Salivary cortisol is routinely used as a diagnostic test for Cushing syndrome. The diagnostic use of salivary cortisol for adrenal insufficiency (AI), however, is less established. We aimed to investigate the utility of morning basal and adrenocorticotropic hormone-stimulated salivary cortisol in diagnosing AI in Korean adults. @*Methods@#We prospectively included 120 subjects (female, n=70) from Seoul National University Hospital. AI was defined as a stimulated serum cortisol level of <496.8 nmol/L during the short Synacthen test (SST). Serum and saliva samples were drawn between 8:00 AM and 10:00 AM. Salivary cortisol levels were measured using an enzyme immunoassay kit. @*Results@#Thirty-four patients were diagnosed with AI according to the SST results. Age, sex, body mass index, serum albumin levels, and serum creatinine levels did not significantly differ between the normal and AI groups. Basal and stimulated salivary cortisol levels were positively correlated with basal (r=0.538) and stimulated serum cortisol levels (r=0.750), respectively (all P<0.001). Receiver operating characteristic curve analysis yielded a cutoff level of morning basal salivary cortisol of 3.2 nmol/L (sensitivity, 84.9%; specificity, 73.5%; area under the curve [AUC]=0.822). The optimal cutoff value of stimulated salivary cortisol was 13.2 nmol/L (sensitivity, 90.7%; specificity, 94.1%; AUC=0.959). Subjects with a stimulated salivary cortisol level above 13.2 nmol/L but a stimulated serum cortisol level below 496.8 nmol/L (n=2) had lower serum albumin levels than those showing a concordant response. @*Conclusion@#The diagnostic performance of stimulated salivary cortisol measurements after the SST was comparable to serum cortisol measurements for diagnosing AI.

Feasibility of a de-epithelialized orbicularis oculi musculocutaneous flap for subbrow blepharoplasty

BACKGROUND: Subbrow blepharoplasty (SBB) has advantages over traditional blepharoplasty in that it results in more natural-looking creases and contours and is more effective for lateral periorbital rejuvenation. However, in older patients with sunken upper eyelid, this procedure might make the superior eyelid sulcus appear worse because the thicker upper eyelid tissue in the subbrow area is replaced by thinner tissue. To overcome this limitation, we developed a de-epithelialized musculocutaneous flap for SBB. METHODS: From August 2016 to January 2018, 13 patients with sunken upper eyelid deformity underwent SBB. For each of these patients, a typical SBB incision was made, but the tissue usually removed in SBB was dissected as a flap based on the branch of the ophthalmic vessel. After elevation, the flap was transposed or folded to correct the sunken deformity. The results were assessed by the patients themselves and by three plastic surgeons at 6 months postoperatively. RESULTS: The mean age of the patients was 63 years (range, 47–81 years). There were no postoperative complications related to wound dehiscence, hypertrophic scarring, or sensory changes. All patients and plastic surgeons provided scores indicating good to excellent results and were satisfied with the cosmetic outcomes. All patients reported improved functional visual acuity after surgery. CONCLUSIONS: Our technique is simple and effectively addresses both sunken upper eyelid deformity and dermatochalasis. Unlike fat or dermofat grafting, our new technique does not require an additional donor site, and it is more reliable in terms of vascularity.

Massive Hemopneumothorax during Breast Augmentation

Although it is very rare, hemopneumothorax can occur during breast augmentation. This potentially fatal surgical complication can be experienced by any plastic surgeon who performs breast augmentation surgery. In this article, we present a case from our institution and review the related literature in order to explore the etiological mechanism of hemopneumothorax, as well as preventive measures and treatments. In addition, we have tried to emphasize the importance of a thorough knowledge of anatomical variations and proper surgical techniques as ways to minimize the likelihood of this complication.

Extension block and direct pinning methods for mallet fracture: A comparative study

BACKGROUND: Mallet fracture can easily occur during sports activities or in daily life; however, the principles and methods of treatment for such fractures remain debated. Among the surgical treatments, various methods of closed reduction have been proposed. We treated patients with the extension block method (EBM) and the direct pinning method (DPM), and then compared the results. We assessed differences in range of motion and measurements of finger movement after surgery. METHODS: A total of 41 patients who underwent surgery from August 2013 to September 2015 were evaluated retrospectively. Among them, 21 patients were treated with the EBM and 20 patients were treated with the DPM. We then compared extensor lag, range of motion, and outcomes according to Crawford’s criteria between before surgery and at 6 to 8 months postoperatively. RESULTS: The postoperative extensor lag improvement was 4.28° and 10.73°, and the postoperative arc of motion was 55.76° and 61.17° in the EBM and DPM groups, respectively. The Crawford assessment showed no statistically significant difference between the groups, although the score in the DPM group was higher than that in the EBM group (3.5 vs. 3.1). CONCLUSIONS: As closed reduction methods for the treatment of mallet fracture, both the EBM and DPM showed good results. However, the DPM proved to be superior to the EBM in that it produced greater improvements in extensor lag and range of motion.

Erratum: Correction of Figure: Clinical Implications of Various Criteria for the Biochemical Diagnosis of Insulinoma

In the original article, the legend of Fig. 1 was incorrect. The solid line was noninsulinoma, and the dotted line was insulinoma.

Characteristics of Korean Patients with Primary Adrenal Insufficiency: A Registry-Based Nationwide Survey in Korea

BACKGROUND: Primary adrenal insufficiency (PAI) is a rare, potentially life-threatening condition. There are few Korean studies on PAI, and most have had small sample sizes. We aimed to examine the etiology, clinical characteristics, treatment, and mortality of PAI in Korean patients. METHODS: A nationwide, multicenter, registry-based survey was conducted to identify adults diagnosed with or treated for PAI at 30 secondary or tertiary care institutions in Korea between 2000 and 2014. RESULTS: A total of 269 patients with PAI were identified. The prevalence of PAI was 4.17 per million. The estimated incidence was 0.45 per million per year. The mean age at diagnosis was 49.0 years, and PAI was more prevalent in men. Adrenal tuberculosis was the most common cause of PAI in patients diagnosed before 2000; for those diagnosed thereafter, adrenal metastasis and tuberculosis were comparable leading causes. The etiology of PAI was not identified in 34.9% of cases. Of the patients receiving glucocorticoid replacement therapy, prednisolone was more frequently administered than hydrocortisone (69.4% vs. 26.5%, respectively), and only 27.1% of all patients received fludrocortisone. We observed an increased prevalence of metabolic disease and osteoporosis during the follow-up period (median, 60.2 months). The observed overall mortality and disease-specific mortality rates were 11.9% and 3.1%, respectively. CONCLUSION: The prevalence of PAI is significantly lower in Koreans than in reports from Western countries. The high frequency undetermined etiology in patients with PAI suggests the need to reveal accurate etiology of PAI in Korea.

Clinical Guidelines for the Management of Adrenal Incidentaloma

An adrenal incidentaloma is an adrenal mass found in an imaging study performed for other reasons unrelated to adrenal disease and often accompanied by obesity, diabetes, or hypertension. The prevalence and incidence of adrenal incidentaloma increase with age and are also expected to rise due to the rapid development of imaging technology and frequent imaging studies. The Korean Endocrine Society is promoting an appropriate practice guideline to meet the rising incidence of adrenal incidentaloma, in cooperation with the Korean Adrenal Gland and Endocrine Hypertension Study Group. In this paper, we discuss important core issues in managing the patients with adrenal incidentaloma. After evaluating core proposition, we propose the most critical 20 recommendations from the initially organized 47 recommendations by Delphi technique.

A New Method of Umbilical Transposition

BACKGROUND: Creating a natural-looking umbilicus during closure of the donor-site in abdominally based free flap breast reconstruction is a factor of satisfaction for both the patient and surgeon. We present a simple method of umbilical transposition that results in an aesthetic, natural-looking umbilicus. METHODS: From March 2011 to November 2014, fifty three consecutive female patients received abdominal flap breast reconstruction. Twenty patients (from March 2011 to February 2013) underwent umbilical transposition through a cross like incision in the abdominal flap, with fascial fixation sutures but no dermal flaps. Thirty three patients (March 2013 to November 2014) received umbilical transposition in the following method. An oval-shaped incision is made at the location of the new umbilicus on the abdominal flap. This oval is deepithelialized, and full-thickness incisions are made at the 2, 6, and 10 o'clock directions to create three triangular dermal flaps. These are pulled down to the abdominal fascia using sutures that pass through the umbilical stalk and the abdominal fascia at the 3, 9, and 12 o'clock directions. This results in an umbilical stalk lined with dermal flaps, creates a natural periumbilical concavity, and anchors the abdominal flap inward to minimize tension. The cranial flap enhances superior hooding. RESULTS: Patient and surgeon satisfaction, surveyed 2 months after surgery with a satisfaction scoring system, were higher in the dermal flap group. CONCLUSIONS: The technique using three dermal flaps in an oval skin incision is simple, relatively easy to learn, and results in an aesthetic, natural-looking umbilicus.

Guidelines for the Management of Adrenal Incidentaloma: the Korean Endocrine Society, Committee of Clinical Practice Guidelines / 대한내과학회지

An adrenal incidentaloma is an adrenal mass found in an imaging examination performed for reasons unrelated to suspected adrenal disease. The prevalence of adrenal incidentaloma increases with age; there is no gender difference, but it is often accompanied by obesity, diabetes mellitus, or hypertension. The detection of adrenal incidentaloma is expected to rise with the rapid development of imaging technology and increasing frequency of imaging studies. The Korean Endocrine Society is promoting appropriate practice guidelines to meet the rising incidence of adrenal incidentaloma, in cooperation with the Korean Adrenal Gland and Endocrine Hypertension Study Group. In this paper, we discuss important core issues for treating adrenal incidentaloma, along with the most important factors for healthcare providers who treat and manage affected patients. Initially, we identified 47 recommendations using the Delphi technique, after evaluating core propositions. We reduced these to the 20 most critical recommendations.

Latissimus Dorsi Tendon Transfer for the Treatment of Irreparable Rotator Cuff Tears

PURPOSE: Massive and irreparable rotator cuff tears present a difficult treatment problem, and if further progressed, then cuff tear arthropaty may develop. We treated seven cases of massive rotator cuff tears with latissimus dorsi tendon transfer and report their clinical results. METHODS: Seven patients of mean age of 64 years (range, 51-70 years) with irreparable massive rotator cuff tears were treated using latissimus dorsi tendon transfer. The latissimus dorsi flap was harvested through an axillary approach and reattached on the greater tuberosity, using transosseous suture with non-absorbable sutures. Outcomes were assessed clinically and radiographically after an average of 48 months (range, 28-68 months). RESULTS: The VAS pain scores improved from 6.3 to 3.3 points (p=0.019). Forward flexion increased from 62° to 105°, abduction increased from 49° to 94°, and external rotation increased from 15° to 34°. Postoperative antero-posterior radiography revealed a mean 0.1 mm depression of the humeral head, without statistical the mean American Shoulder and Elbow Surgeons score improved from 44 to 76. The acromiohumeral distance showed slight increase in amount of 0.1 mm without statistical significance. There was no complication. CONCLUSION: Latissimus dorsi transfer is a useful surgical option for treating irreparable massive rotator cuff tears.

Radiographic Characteristics of Adrenal Masses in Oncologic Patients

BACKGROUND: We aimed to assess the usefulness of pre-contrast Hounsfield unit (HU) and mass size on computed tomography to differentiate adrenal mass found incidentally in oncologic patients. METHODS: From 2000 to 2012, 131 oncologic patients with adrenal incidentaloma were reviewed retrospectively. Receiver operating characteristic (ROC) curves were applied to determine the optimal cut-off value of the mean HU and size for detecting adrenal metastasis. RESULTS: The median age was 18 years, and 80 patients were male. The initial mass size was 18 mm, and 71 (54.2%) of these were on the left side. A bilateral adrenal mass was found in 11 patients (8.4%). Biochemically functional masses were observed in 9.2% of patients. Thirty-six out of 119 patients with nonfunctional masses underwent adrenalectomy, which revealed metastasis in 13. The primary cancers were lung cancer (n=4), renal cell carcinoma (n=2), lymphoma (n=2), hepatocellular carcinoma (n=2), breast cancer (n=1), and others (n=2). The area under the curve for the size and HU for clinically suspicious metastasis were 0.839 (95% confidence interval [CI], 0.761 to 0.900; P20 can be used as a diagnostic reference to suggest metastasis in oncologic patients with adrenal masses.

Diagnostic Role of Captopril Challenge Test in Korean Subjects with High Aldosterone-to-Renin Ratios

BACKGROUND: Diagnosis of primary aldosteronism (PA) begins with aldosterone-to-renin ratio (ARR) measurement followed by confirmative tests. However, the ARR has high false positive rates which led to unnecessary confirmatory tests. Captopril challenge test (CCT) has been used as one of confirmatory tests, but the accuracy of it in the diagnosis of PA is still controversial. We aimed to examine the clinical efficacy of CCT as a post-screening test in PA. METHODS: In a prospective study, we enrolled subjects with suspected PA who had hypertension and ARR >20 (ng/dL)/(ng/mL/hr). Sixty-four patients who underwent both the saline infusion test and the CCT were included. RESULTS: The diagnostic performance of plasma aldosterone concentration (PAC) post-CCT was greater than that of ARR post-CCT and ARR pre-CCT in PA (area under the curve=0.956, 0.797, and 0.748, respectively; P=0.001). A cut-off value of 13 ng/dL showed the highest diagnostic odds ratio considering PAC post-CCT at 60 and 90 minutes. A PAC post-CCT of 19 ng/dL had a specificity of 100%, which can be used as a cut-off value for the confirmative test. Determining the diagnostic performance of PAC post-CCT at 90 minutes was sufficient for PA diagnosis. Subjects with PAC post-CCT at 90 minutes <13 ng/dL are less likely to have PA, and those with PAC post-CCT at 90 minutes ≥13 but <19 ng/dL should undergo secondary confirmatory tests. CONCLUSION: The CCT test may be a reliable post-screening test to avoid the hospitalization in the setting of falsely elevated ARR screening tests.

1,5-Anhydro-D-Glucitol Could Reflect Hypoglycemia Risk in Patients with Type 2 Diabetes Receiving Insulin Therapy

BACKGROUND: The identification of a marker for hypoglycemia could help patients achieve strict glucose control with a lower risk of hypoglycemia. 1,5-Anhydro-D-glucitol (1,5-AG) reflects postprandial hyperglycemia in patients with well-controlled diabetes, which contributes to glycemic variability. Because glycemic variability is related to hypoglycemia, we aimed to evaluate the value of 1,5-AG as a marker of hypoglycemia. METHODS: We enrolled 18 adults with type 2 diabetes mellitus (T2DM) receiving insulin therapy and assessed the occurrence of hypoglycemia within a 3-month period. We measured 1,5-AG level, performed a survey to score the severity of hypoglycemia, and applied a continuous glucose monitoring system (CGMS). RESULTS: 1,5-AG was significantly lower in the high hypoglycemia-score group compared to the low-score group. Additionally, the duration of insulin treatment was significantly longer in the high-score group. Subsequent analyses were adjusted by the duration of insulin treatment and mean blood glucose, which was closely associated with both 1,5-AG level and hypoglycemia risk. In adjusted correlation analyses, 1,5-AG was negatively correlated with hypoglycemia score, area under the curve at 80 mg/dL, and low blood glucose index during CGMS (P=0.068, P=0.033, and P=0.060, respectively). CONCLUSION: 1,5-AG level was negatively associated with hypoglycemia score determined by recall and with documented hypoglycemia after adjusting for mean glucose and duration of insulin treatment. As a result, this level could be a marker of the risk of hypoglycemia in patients with well-controlled T2DM receiving insulin therapy.

Identification of Two Cases of Ciliopathy-Associated Diabetes and Their Mutation Analysis Using Whole Exome Sequencing

BACKGROUND: Alstrom syndrome and Bardet-Biedl syndrome are autosomal recessively inherited ciliopathies with common characteristics of obesity, diabetes, and blindness. Alstrom syndrome is caused by a mutation in the ALMS1 gene, and Bardet-Biedl syndrome is caused by mutations in BBS1-16 genes. Herein we report genetically confirmed cases of Alstrom syndrome and Bardet-Biedl syndrome in Korea using whole exome sequencing. METHODS: Exome capture was done using SureSelect Human All Exon Kit V4+UTRs (Agilent Technologies). HiSeq2000 system (Illumina) was used for massive parallel sequencing. Sanger sequencing was used for genotype confirmation and familial cosegregation analysis. RESULTS: A 21-year old Korean woman was clinically diagnosed with Alstrom syndrome. She had diabetes, blindness, obesity, severe insulin resistance, and hearing loss. Whole exome sequencing revealed a nonsense mutation in exon 10 of ALMS1 (c.8776C>T, p.R2926X) and a seven base-pair deletion resulting in frameshift mutation in exon 8 (c.6410_6416del, p.2137_2139del). A 24-year-old Korean man had Bardet-Biedl syndrome with diabetes, blindness, obesity, and a history of polydactyly. Whole exome sequencing revealed a nonsynonymous mutation in exon 11 of the BBS1 gene (c.1061A>G, p.E354G) and mutation at the normal splicing recognition site of exon 7 of the BBS1 gene (c.519-1G>T). CONCLUSION: We found novel compound heterozygous mutations of Alstrom syndrome and Bardet-Biedl syndrome using whole exome sequencing. The whole exome sequencing successfully identified novel genetic variants of ciliopathy-associated diabetes.

Limited Diagnostic Utility of Plasma Adrenocorticotropic Hormone for Differentiation between Adrenal Cushing Syndrome and Cushing Disease

BACKGROUND: Measurement of the plasma adrenocorticotropic hormone (ACTH) level has been recommended as the first diagnostic test for differentiating between ACTH-independent Cushing syndrome (CS) and ACTH-dependent CS. When plasma ACTH values are inconclusive, a differential diagnosis of CS can be made based upon measurement of the serum dehydroepiandrosterone sulfate (DHEA-S) level and results of the high-dose dexamethasone suppression test (HDST). The aim of this study was to assess the utility of plasma ACTH to differentiate adrenal CS from Cushing' disease (CD) and compare it with that of the HDST results and serum DHEA-S level. METHODS: We performed a retrospective, multicenter study from January 2000 to May 2012 involving 92 patients with endogenous CS. The levels of plasma ACTH, serum cortisol, 24-hour urine free cortisol (UFC) after the HDST, and serum DHEA-S were measured. RESULTS: Fifty-seven patients had adrenal CS and 35 patients had CD. The area under the curve of plasma ACTH, serum DHEA-S, percentage suppression of serum cortisol, and UFC after HDST were 0.954, 0.841, 0.950, and 0.997, respectively (all P<0.001). The cut-off values for plasma ACTH, percentage suppression of serum cortisol, and UFC after HDST were 5.3 pmol/L, 33.3%, and 61.6%, respectively. The sensitivity and specificity of plasma ACTH measurement were 84.2% and 94.3%, those of serum cortisol were 95.8% and 90.6%, and those of UFC after the HDST were 97.9% and 96.7%, respectively. CONCLUSION: Significant overlap in plasma ACTH levels was seen between patients with adrenal CS and those with CD. The HDST may be useful in differentiating between these forms of the disease, especially when the plasma ACTH level alone is not conclusive.

Diagnosis and Treatment of Hypopituitarism

Hypopituitarism is a chronic endocrine illness that caused by varied etiologies. Clinical manifestations of hypopituitarism are variable, often insidious in onset and dependent on the degree and severity of hormone deficiency. However, it is associated with increased mortality and morbidity. Therefore, early diagnosis and prompt treatment is necessary. Hypopituitarism can be easily diagnosed by measuring basal pituitary and target hormone levels except growth hormone (GH) and adrenocorticotropic hormone (ACTH) deficiency. Dynamic stimulation tests are indicated in equivocal basal hormone levels and GH/ACTH deficiency. Knowledge of the use and limitations of these stimulation tests is mandatory for proper interpretation. It is necessary for physicians to inform their patients that they may require lifetime treatment. Hormone replacement therapy should be individualized according to the specific needs of each patient, taking into account possible interactions. Long-term endocrinological follow-up of hypopituitary patients is important to monitor hormonal replacement regimes and avoid under- or overtreatment.

Effect of Zhubin (KI9) acupuncture in reducing alcohol craving in patients with alcohol dependence: A randomized placebo-controlled trial / 中国结合医学杂志

<p><b>OBJECTIVE</b>To examine the effect of acupuncture on Zhubin (KI9) in reducing alcohol craving in alcohol-dependent patients.</p><p><b>METHODS</b>Twenty male alcohol-dependent patients were randomly assigned to two groups, a treatment group (10 cases, age 43.0±6.8 years) and a placebo group (10 cases, age 44.5±7.9 years). The treatment group was treated with real needle acupuncture on Zhubin (KI9) twice a week for 4 weeks, and the control group was treated with placebo needle acupuncture. Both groups were given acupuncture treatment using Park Sham Device (PSD). Alcohol craving was measured by the Visual Analogue Scale (VAS) before treatment to establish a baseline, and after 1, 2, and 4 weeks of treatment. Repeated measures ANOVA was used to determine the main and interaction effects of time and on the outcome measure (VAS).</p><p><b>RESULTS</b>There was a significant effect of time on VAS score (df=3, F=13.3, P<0.01). Main effect of group on VAS score was significant (df=1, F=10.9, P<0.01) and the time×group interaction was also significant (df=3, F=4.7, P<0.01).</p><p><b>CONCLUSIONS</b>Real-needle acupuncture therapy on Zhubin (KI9) showed effectiveness in reducing alcohol craving. These results strongly suggest the usefulness of acupuncture therapy on Zhubin (KI9) in preventing a relapse in alcohol dependent patients.</p>

Clinical Implications of Various Criteria for the Biochemical Diagnosis of Insulinoma

BACKGROUND: Among the various diagnostic criteria for insulinoma, the ratio criteria have been controversial. However, the amended insulin-glucose ratio exhibited excellent diagnostic performance in a recent retrospective cohort study, although it has not yet been validated in other patient cohorts. We examined the diagnostic performance of the current criteria of the Endocrine Society, insulin-glucose ratio, C-peptide-glucose ratio, and amended ratios in terms of differentiating insulinomas. METHODS: We reviewed the medical records of patients who underwent evaluation for hypoglycemia from 2000 to 2013. Fourteen patients with histopathologically confirmed insulinoma and 18 patients without clinical evidence of insulinoma were included. The results of a prolonged fast test were analyzed according to the abovementioned criteria. RESULTS: Fulfilling all three Endocrine Society criteria-plasma levels of glucose ( or =8 pmol/L), and C-peptide (> or =0.2 nmol/L)-exhibited 100% sensitivity and 89% specificity. Fulfilling the glucose and C-peptide criteria showed 100% sensitivity and 83% specificity, while fulfilling the glucose and insulin criteria showed 100% sensitivity and 72% specificity. Among the ratio criteria, the insulin-glucose ratio [>24.0 (pmol/L)/(mmol/L)] gave the highest area under the receiver operating characteristic curve, with 93% sensitivity and 94% specificity. CONCLUSION: Fulfilling the glucose, insulin, and C-peptide criteria of the Endocrine Society guidelines exhibited the best diagnostic performance for insulinoma. Nonetheless, the insulin-glucose ratio may still have a role in the biochemical diagnosis of insulinoma.

Medical doctors as the captain of a ship: an analysis of medical students' book reports on Joseph Conrad's "Lord Jim" / 보건의료교육평가

PURPOSE: In South Korean ferry disaster in 2014, the captain abandoned the ship with passengers including high school students still aboard. We noticed the resemblance of abandoning the ship with passengers still aboard the ferry (named the Sewol) and the ship Patna, which was full of pilgrims, in Joseph Conrad's novel "Lord Jim." The aim of this study is to see how medical students think about the role of a medical doctor as a captain of a ship by analyzing book reports on Conrad's "Lord Jim." METHODS: Participants included 49 third-year medical students. Their book reports were analyzed. RESULTS: If placed in the same situation as the character of Jim, 24 students of the 49 respondents answered that they would stay with the passengers, while 18 students indicated they would escape from the ship with the crew. Most of the students thought the role of a doctor in the medical field was like that of a 'captain.' The medical students reported that they wanted to be a doctor who is responsible for his or her patients, highly moral, warm-hearted, honest, and with high self-esteem. CONCLUSION: In conclusion, we found that "Lord Jim" induced the virtue of 'responsibility' from the medical students. Consequently, "Lord Jim" could be good teaching material for medical humanities.

Clinical Characteristics of the Responders to Dipeptidyl Peptidase-4 Inhibitors in Korean Subjects with Type 2 Diabetes

We investigated characteristics associated with the efficacy of dipeptidyl peptidase-4 inhibitors (DPP4i) in Korean patients with type 2 diabetes. We reviewed medical records of 477 patients who had taken sitagliptin or vildagliptin longer than 40 weeks. Response to DPP4i was evaluated with HbA1c change after therapy (DeltaHbA1c). The Student's t-test between good responders (GR: DeltaHbA1c > 1.0%) and poor responders (PR: DeltaHbA1c < 0.5%), a correlation analysis among clinical parameters, and a linear multivariate regression analysis were performed. The mean age was 60 yr, duration of diabetes 11 yr and HbA1c was 8.1%. Baseline fasting plasma glucose (FPG), HbA1c, C-peptide, and creatinine were significantly higher in the GR compared to the PR. Duration of diabetes, FPG, HbA1c, C-peptide and creatinine were significantly correlated with DeltaHbA1c. In the multivariate analysis, age (r2 = 0.006), duration of diabetes (r2 = 0.019), HbA1c (r2 = 0.296), and creatinine levels (r2 = 0.024) were independent predictors for the response to DPP4i. Body mass index and insulin resistance were not associated with the response to DPP4i. In conclusion, better response to DPP4i would be expected in Korean patients with type 2 diabetes who have higher baseline HbA1c and creatinine levels with shorter duration of diabetes.