Sang Woo Oh

Effects of Excess Weight on Cancer Incidences Depending on Cancer Sites and Histologic Findings Among Men: Korea National Health Insurance Corporation Study

PURPOSE The effects of excess weight on the development of cancers are controversial, and little is known for populations outside the United States and Europe. We conducted this study to assess the effects of excess weight with a large cohort of Koreans. METHODS We assessed the relationship between body mass index (BMI) and various cancers in a 10-year follow-up cohort of 781,283 Korean men who were free of prior cancer at baseline. Weight and height were measured, and questionnaires related to health behaviors and medical history were completed. Data on newly developed cancers were obtained from two organizations in Korea. A proportional hazards model was used to examine the relationship between BMI and cancer. RESULTS Adenocarcinoma in the colon and rectosigmoid, hepatocellular carcinoma, cholangiocarcinoma, adenocarcinoma in the prostate, renal cell carcinoma, papillary carcinoma in the thyroid, small-cell carcinoma in the lung, non-Hodgkins lymphoma, and melanoma had positive dose-dependent relationships with BMI (all P < .05). Although no linear trend was found (P = .267), obese men who never smoked with a BMI of >or= 30 kg/m(2) had an increased risk of developing gastric adenocarcinoma (relative risk = 1.73). Other cancers, such as leukemia, multiple myeloma, and gallbladder and pancreatic cancer, did not show significant associations. CONCLUSION These findings show that, even in Koreans, obesity clearly increases the risk of many types of cancers and the strength of the associations varies with the organ and histologic type. Because these obesity-related cancers are reported to be rapidly increasing in Korea and many other Asian countries, controlling obesity epidemics could be an effective tool for preventing these cancers in these areas.

Socioeconomic Status in Relation to Obesity and Abdominal Obesity in Korean Adults: A Focus on Sex Differences

Objective: We examined the relationship between income and education level with BMI and waist circumference to provide further understanding of the relationship between socioeconomic status and obesity and to identify the presence of sex differences.

Elevated intraocular pressure is associated with insulin resistance and metabolic syndrome

Elevated intraocular pressure (IOP), a well‐known risk factor for glaucoma, has recently been shown to be associated with some metabolic complications and obesity. We investigated the link between IOP and metabolic disturbances, focusing especially on metabolic syndrome and insulin resistance.

Central Obesity as a Risk Factor for Prostatic Hyperplasia

Objective: Obesity‐related metabolic diseases may influence prostatic hyperplasia. This study examined the impact of obesity on prostate volume in men without overt obesity‐related metabolic diseases.

Effects of exercise-induced weight loss on acylated and unacylated ghrelin in overweight children

Objective  Controversial data on ghrelin concentration during exercise in human subjects have been published. We tested the hypothesis that exercise could affect acylated ghrelin (AG) and unacylated ghrelin (UAG), which could partly explain the previously reported inconsistent findings on the association of exercise with changes in ghrelin.

Adipokines, insulin resistance, metabolic syndrome, and breast cancer recurrence: a cohort study.

IntroductionSeveral in vitro studies have suggested the effects of adipokines and insulin resistance on breast cancer cell proliferation and survival. However, little is known about the clinical significance of these findings.MethodsWe examined associations between breast cancer recurrence and adiponectin, leptin, insulin resistance, and metabolic syndrome (MetS) in a cohort of 747 patients from 2001 to 2004.ResultsAdjusted hazard ratios showed an inverse trend across the quartiles for serum adiponectin concentration in estrogen receptor (ER)/progesterone receptor (PR) -negative patients (P for trend = 0.027) but not in ER/PR-positive patients. Compared to the highest quartile for adiponectin level, the lowest quartile showed a hazard ratio of 2.82 (1.03 to 7.68). Homeostasis model assessment for insulin resistance (HOMA-IR) showed a positive trend for recurrence in the ER/PR-negative group (P for trend = 0.087) and a negative trend in the ER/PR-positive group (P for trend = 0.081). Leptin did not show any associations (P for trend >0.05). A linear trend was observed with the number of components of MetS in ER/PR-negative patients (P for trend = 0.044). This association disappeared when adjusted for adiponectin and HOMA-IR.ConclusionsAdiponectin and HOMA-IR have prognostic significance in breast cancer recurrence and interventions related to these factors may protect against recurrence in ER/PR-negative patients. These findings were not observed in the case of ER/PR-positive patients. Further evaluation of these insignificant associations is needed because it might be biased by adjuvant chemotherapy or other confounders.

Cigarette Smoking Increases Abdominal and Visceral Obesity but Not Overall Fatness: An Observational Study

Background Cigarette smoking and obesity are leading public health concerns. Both increase the risk for cardiovascular disease, cancer, and metabolic abnormalities. This study was conducted to assess the association between cigarette smoking and different types of obesity. Methodology/Principal Findings Two hundred eighty-three visitors to university hospitals located in four main provinces of South Korea were participated. All participants were classified as either current/past or never smokers and were divided into quartiles according to the total pack-years. Body mass index, waist circumference, total body fat percentage, and area of visceral and abdominal subcutaneous fat were measured. These results of each groups were compared. Waist circumference, and visceral fat area showed a J- or U-shaped association with total smoking amount during a lifetime. After restricting the analyses to past/current smokers, we found significant dose-dependent associations of smoking pack-years with abdominal and visceral obesity. Overall obesity measured by body mass index and total body fat percentage did not show such associations. Although current smokers clearly showed significant associations, we could not demonstrate these in past smokers, possibly because of the limited sample size. Conclusions/Significance Although smokers did not show significant difference in mean body mass index than those who never smoked, they showed more metabolically adverse fat distributions with increasing smoking amounts. This finding suggests that smoking is not beneficial for weight control. Therefore, smoking cessation and avoidance of smoking commencement should be addressed as important public health issues in preventing obesity and related complications.

The influence of the eradication of Helicobacter pylori on gastric ghrelin, appetite, and body mass index in patients with peptic ulcer disease

Background and Aim:  Helicobacter pylori (H. pylori) infection has been known to influence the gastric leptin and ghrelin secretion, for which the exact pathogenic role has not been documented yet. This study was designed to investigate the influence of H. pylori eradication on plasma or gastric levels of ghrelin, body mass index (BMI), and resultant levels of appetite in patients with peptic ulcer disease.

Novel genetic variations associated with salt sensitivity in the Korean population

Salt sensitivity is a risk factor for cardiovascular morbidity and mortality. To date, only a few genetic variations have been identified as being associated with salt sensitivity. This study aimed to estimate the prevalence of salt sensitivity in the Korean population and to identify genetic variants affecting its development. A total of 101 Korean participants consumed a low-salt diet for 7 days followed by a high-salt diet for 7 additional days. Salt sensitivity was determined by noting any significant elevation in the 24-h mean arterial blood pressure. To determine genetic variants affecting salt sensitivity, 36 single-nucleotide polymorphisms (SNPs) that were previously reported to be associated with hypertension were tested for any associations with salt sensitivity. Of the 101 subjects, 28 (27.7%) were determined to have salt sensitivity. Out of the 36 SNPs tested, four were significantly associated with salt sensitivity after adjusting for confounding factors: rs2681472 in ATPase, Ca++ transporting, plasma membrane 1 (ATP2B1), rs7961152 in branched chain aminotransferase 1 (BCAT1), rs16998073 in fibroblast growth factor 5 (FGF5) and rs2398162 in LOC100132798. For rs3754777 in serine threonine kinase 39 (STK39) and rs1937506, associations with salt sensitivity were observed before adjusting for confounding factors. Haplotype analysis revealed that the A-C haplotype of rs3754777–rs6749447 in STK39 was more frequent in the salt-sensitive group compared with the salt-resistant group, and was associated with salt sensitivity. This study estimates the prevalence of salt sensitivity in the Korean population and demonstrates a novel association between salt sensitivity and the ATP2B1, BCAT1, FGF5, LOC100132798 and STK39 genetic variations.

Dairy Product Intake Is Inversely Associated with Metabolic Syndrome in Korean Adults: Anseong and Ansan Cohort of the Korean Genome and Epidemiology Study

The objective of this study was to examine the relationship between dairy product intake and the incidence of metabolic syndrome (MetS) and its components among middle-aged Koreans. We examined 7,240 adults aged 40-69 yr without MetS at baseline over a 45.5-month follow-up period. They were taken from the Anseong and Ansan cohort of the Korean Genome and Epidemiology Study. Dairy product intake including milk, yogurt, and cheese was assessed with food frequency questionnaire. At the follow-up, the incidence of MetS was 17.1%. The incidences of MetS components were as follows: low HDL cholesterol (16.2%), abdominal obesity (14.0%), hypertriglyceridemia (13.8%), hyperglycemia (13.3%), and hypertension (13.1%). Adjusting for potential confounders, dairy product consumption frequency was inversely associated with the risk of MetS and abdominal obesity. Hazard ratio (HR) (95% confidence interval) for dairy product consumption more than 7 times/week compared to never was 0.75 (0.64-0.88, P for trend < 0.001) for MetS and 0.73 (0.61-0.88, P for trend < 0.001) for abdominal obesity. HR for milk intake was 0.79 for MetS and 0.82 for abdominal obesity. The results of this study suggest that daily intake of dairy products protects against the development of MetS, particularly abdominal obesity, in middle-aged Koreans.