Serum 25-Hydroxyvitamin D Levels and Risk of Colorectal Cancer: An Age-Stratified Analysis.

BACKGROUND & AIMS: The role of circulating 25-hydroxyvitamin D (25(OH)D) in the prevention of early-onset colorectal cancer (CRC) in young adults aged <50 years is uncertain. We evaluated the age-stratified associations (<50 vs ≥50 years) between circulating 25(OH)D levels and the risk of CRC in a large sample of Korean adults. METHODS: Our cohort study included 236,382 participants (mean age, 38.0 [standard deviation, 9.0] years) who underwent a comprehensive health examination, including measurement of serum 25(OH)D levels. Serum 25(OH)D levels were categorized as <10, 10 to 20, and ≥20 ng/mL. CRC, along with the histologic subtype, site, and invasiveness, was ascertained through linkage with the national cancer registry. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CRC according to the serum 25(OH)D status, with adjustment for potential confounders. RESULTS: During the 1,393,741 person-years of follow-up (median, 6.5 years; interquartile range, 4.5-7.5 years), 341 participants developed CRC (incidence rate, 19.2 per 105 person-years). Among young individuals aged <50 years, serum 25(OH)D levels were inversely associated with the risk of incident CRC with HRs (95% CIs) of 0.61 (0.43-0.86) and 0.41 (0.27-0.63) for 25(OH)D 10 to 19 ng/mL and ≥20 ng/mL, respectively, with respect to the reference (<10 ng/mL) (P for trend <.001, time-dependent model). Significant associations were evident for adenocarcinoma, colon cancer, and invasive cancers. For those aged ≥50 years, associations were similar, although slightly attenuated compared with younger individuals. CONCLUSIONS: Serum 25(OH)D levels may have beneficial associations with the risk of developing CRC for both early-onset and late-onset disease.

Allergic Diseases and Risk of Incident Dementia and Alzheimer's Disease.

OBJECTIVE: To examine the associations between the allergic triad (asthma, allergic rhinitis, atopic dermatitis) and risk of dementia. METHODS: Participants comprised 6,785,948 adults aged ≥40 years who participated in a national health examination in 2009 without any history of dementia before baseline. From 2009 to 2017, we prospectively investigated the associations between physician-diagnosed allergic diseases and risk of incident dementia (all-cause, Alzheimer's disease [AD], vascular dementia [VaD]) ascertained using national health insurance claims data. RESULTS: During 8.1 years of follow-up, 260,705 dementia cases (195,739 AD, 32,789 VaD) were identified. Allergic diseases were positively associated with dementia risk. Compared with individuals without allergic diseases, multivariable hazard ratios (HRs) of all-cause dementia were 1.20 (95% confidence interval [CI] 1.19-1.22) in those with asthma, 1.10 (95% CI 1.09-1.12) with allergic rhinitis, 1.16 (95% CI 1.11-1.21) with atopic dermatitis, and 1.13 (95% CI 1.12-1.14) with any of these allergies. Similarly, individuals with any of the allergic triad had a higher risk of AD (HR 1.16, 95% CI 1.14-1.17) and VaD (HR 1.04; 95% CI 1.01-1.06) than those without any allergic disease. As the number of comorbid allergic diseases increased, the risk of dementia increased linearly (Ptrend ≤ 0.002). Compared with individuals without allergies, those with all three allergic diseases had substantially increased risk of all-cause dementia (HR 1.54, 95% CI 1.35-1.75), AD (HR 1.46; 95% CI 1.25-1.70), and VaD (HR 1.99, 95% CI 1.44-2.75). INTERPRETATION: Asthma, allergic rhinitis, and atopic dermatitis were significantly associated with increased risk of all-cause dementia and subtypes, with dose-effect relationships with the severity of allergic diseases. ANN NEUROL 2023;93:384-397.

Long-Term Leisure-Time Physical Activity Intensity and All-Cause and Cause-Specific Mortality: A Prospective Cohort of US Adults.

BACKGROUND: The 2018 physical activity guidelines for Americans recommend a minimum of 150 to 300 min/wk of moderate physical activity (MPA), 75 to 150 min/wk of vigorous physical activity (VPA), or an equivalent combination of both. However, it remains unclear whether higher levels of long-term VPA and MPA are, independently and jointly, associated with lower mortality. METHODS: A total of 116 221 adults from 2 large prospective US cohorts (Nurses' Health Study and Health Professionals Follow-up Study, 1988-2018) were analyzed. Detailed self-reported leisure-time physical activity was assessed with a validated questionnaire, repeated up to 15 times during the follow-up. Cox regression was used to estimate the hazard ratio and 95% CI of the association between long-term leisure-time physical activity intensity and all-cause and cause-specific mortality. RESULTS: During 30 years of follow-up, we identified 47 596 deaths. In analyses mutually adjusted for MPA and VPA, hazard ratios comparing individuals meeting the long-term leisure-time VPA guideline (75-149 min/wk) versus no VPA were 0.81 (95% CI, 0.76-0.87) for all-cause mortality, 0.69 (95% CI, 0.60-0.78) for cardiovascular disease (CVD) mortality, and 0.85 (95% CI, 0.79-0.92) for non-CVD mortality. Meeting the long-term leisure-time MPA guideline (150-299 min/wk) was similarly associated with lower mortality: 19% to 25% lower risk of all-cause, CVD, and non-CVD mortality. Compared with those meeting the long-term leisure-time physical activity guidelines, participants who reported 2 to 4 times above the recommended minimum of long-term leisure-time VPA (150-299 min/wk) or MPA (300-599 min/wk) showed 2% to 4% and 3% to 13% lower mortality, respectively. Higher levels of either long-term leisure-time VPA (≥300 min/wk) or MPA (≥600 min/wk) did not clearly show further lower all-cause, CVD, and non-CVD mortality or harm. In joint analyses, for individuals who reported <300 min/wk of long-term leisure-time MPA, additional leisure-time VPA was associated with lower mortality; however, among those who reported ≥300 min/wk of long-term leisure-time MPA, additional leisure-time VPA did not appear to be associated with lower mortality beyond MPA. CONCLUSIONS: The nearly maximum association with lower mortality was achieved by performing ≈150 to 300 min/wk of long-term leisure-time VPA, 300 to 600 min/wk of long-term leisure-time MPA, or an equivalent combination of both.

Simple Sugar and Sugar-Sweetened Beverage Intake During Adolescence and Risk of Colorectal Cancer Precursors.

BACKGROUND & AIMS: Recent increasing trends in early-onset colorectal cancer (CRC) strongly supports that early-life diet is involved in CRC development. However, data are lacking on the relationship with high sugar intake during early life. METHODS: We prospectively investigated the association of adolescent simple sugar (fructose, glucose, added sugar, total sugar) and sugar-sweetened beverage (SSB) intake with CRC precursor risk in 33,106 participants of the Nurses' Health Study II who provided adolescent dietary information in 1998 and subsequently underwent lower gastrointestinal endoscopy between 1999 and 2015. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression for clustered data. RESULTS: During follow-up, 2909 conventional adenomas (758 high-risk) and 2355 serrated lesions were identified (mean age at diagnoses, 52.2 ± 4.3 years). High sugar and SSB intake during adolescence was positively associated with risk of adenoma, but not serrated lesions. Per each increment of 5% of calories from total fructose intake, multivariable ORs were 1.17 (95% CI, 1.05-1.31) for total and 1.30 (95% CI, 1.06-1.60) for high-risk adenoma. By subsite, ORs were 1.12 (95% CI, 0.96-1.30) for proximal, 1.24 (95% CI, 1.05-1.47) for distal, and 1.43 (95% CI, 1.10-1.86) for rectal adenoma. Per 1 serving/day increment in SSB intake, ORs were 1.11 (95% CI, 1.02-1.20) for total and 1.30 (95% CI, 1.08-1.55) for rectal adenoma. Contrary to adolescent intake, sugar and SSB intake during adulthood was not associated with adenoma risk. CONCLUSIONS: High intake of simple sugars and SSBs during adolescence was associated with increased risk of conventional adenoma, especially rectal adenoma.

Sugar-sweetened beverage intake in adulthood and adolescence and risk of early-onset colorectal cancer among women.

OBJECTIVE: Sugar-sweetened beverage (SSB) consumption had substantially increased across successive US birth cohorts until 2000, and adolescents and young adults under age 50 years have the highest consumption. However, the link between SSBs and early-onset colorectal cancer (EO-CRC) remains unexamined. DESIGN: In the Nurses' Health Study II (1991-2015), we prospectively investigated the association of SSB intake in adulthood and adolescence with EO-CRC risk among 95 464 women who had reported adulthood beverage intake using validated food frequency questionnaires (FFQs) every 4 years. A subset of 41 272 participants reported beverage intake at age 13-18 years using a validated high school-FFQ in 1998. Cox proportional hazards models were used to estimate relative risks (RRs) with 95% CIs. RESULTS: We documented 109 EO-CRC cases. Compared with individuals who consumed <1 serving/week of SSBs in adulthood, women who consumed ≥2 servings/day had a more than doubled risk of EO-CRC (RR 2.18; 95% CI 1.10 to 4.35; ptrend=0.02), with a 16% higher risk (RR 1.16; 95% CI 1.00 to 1.36) per serving/day increase. Each serving/day increment of SSB intake at age 13-18 years was associated with a 32% higher risk of EO-CRC (RR 1.32; 95% CI 1.00 to 1.75). Replacing each serving/day of adulthood SSB intake with that of artificially sweetened beverages, coffee, reduced fat milk or total milk was associated with a 17%-36% lower risk of EO-CRC. CONCLUSION: Higher SSB intake in adulthood and adolescence was associated with a higher risk of EO-CRC among women. Reduction of SSB consumption among adolescents and young adults may serve as a potential strategy to alleviate the growing burden of EO-CRC.

Fecal incontinence knowledge, attitudes, and help-seeking behaviors among community-dwelling adults in Korea.

OBJECTIVES: Fecal incontinence (FI) is a common debilitating disorder that tends to be underreported. Although low health literacy likely contributes to the underreporting, studies on FI knowledge among the general population remain scarce. We investigated how FI knowledge is associated with attitudes and help-seeking behaviors. METHODS: We conducted a cross-sectional survey among community-dwelling adults undergoing national health screening in Korea. A structured, self-administered questionnaire was used to assess FI knowledge, attitudes, and help-seeking behaviors. Odds ratios (ORs; 95% confidence intervals, CIs) were estimated using logistic regression with adjustment for covariables. RESULTS: Of the 601 participants completing the survey, only 29.8% were aware of the term FI, and their knowledge levels were insufficient. As for FI-related attitudes, 24.6% considered FI to be very rare, and 22.3% considered it to be moderately or less distressing. Individuals who knew the term FI tended to consider FI more common (OR: 2.45; 95%CI: 1.49-4.02) and distressing (OR: 1.68; 95%CI: 1.07-2.63) than those without knowledge. Assuming future FI occurrence, those considering FI to be distressing were less willing to ignore or self-manage the condition (OR: 0.25; 95%CI: 0.11-0.58). Among patients with FI (n = 83), only 30.1% had sought help and 8.4% had consulted doctors. Knowing the term FI was significantly associated with overall help-seeking behavior (OR: 9.23; 95%CI: 2.09-40.77). CONCLUSIONS: FI knowledge levels and help-seeking rates were low among community-dwelling adults. FI knowledge was significantly associated with attitudes and help-seeking behaviors. Future public education programs are warranted to improve FI knowledge, attitudes, and help-seeking behaviors.

Association Between Premature Hair Greying and Metabolic Risk Factors: A Cross-sectional Study.

The association of hair greying with metabolic syndrome is not well known, while association with obesity and coronary artery disease has been suggested. A cross-sectional study was conducted to identify an association between premature hair greying and metabolic risk factors. Of the 1,929 young healthy subjects (1,067 men and 862 women), 704 (36.4%) were categorized in the premature hair greying group. Waist circumference (means of non-premature hair greying vs. premature hair greying, 74.3 vs. 76.3 cm; p < 0.001), systolic (109.2 vs. 111.7 mmHg; p<0.001) and diastolic (65.0 vs. 66.2 mmHg; p = 0.003) blood pressures, and fasting blood sugar (90.8 vs. 91.6 mg/dl; p = 0.013) were higher and serum high-density lipoprotein cholesterol (68.1 vs 65.4 mg/dl; p < 0.001) was lower in premature hair greying group. Multivariate logistic regression analysis showed that metabolic risk factors ≥ 2 was independently associated with premature hair greying after controlling for confounding factors (odds ratio 1.725; p = 0.036). The present study revealed an association between premature hair greying and metabolic risk factors.

Is Vitamin D an Independent Risk Factor of Nonalcoholic Fatty Liver Disease?: a Cross-Sectional Study of the Healthy Population.

The association between vitamin D levels and nonalcoholic fatty liver disease (NAFLD) has been recognized. However, few studies showed independent associations between vitamin D deficiency and NAFLD after a sex-related adjustment for metabolic factors. We aimed to study whether vitamin D deficiency is an independent risk factor of NAFLD even after controlling for metabolic syndrome and visceral fat in both sexes. In this cross-sectional study, 7,514 Korean adults (5,278 men, 2,236 women) participated in a health check-up program. They underwent blood tests, abdominal computed tomography (CT) of the visceral fat area, and ultrasonography for NAFLD screening. Multiple logistic regression analysis was used to investigate the association of vitamin D deficiency with NAFLD according to the sex differences. Vitamin D deficiency is associated with NAFLD. The adjusted odds ratio (aOR) for NAFLD increased sequentially with decreasing vitamin D level, even after adjusting for metabolic syndrome and visceral fat. The subjects in the vitamin D sufficiency group (20-30 ng/mL) had an aOR for NAFLD of 1.18 (95% CI, 1.00-1.39), whereas the deficiency group (< 20 ng/mL) had an aOR of 1.29 (95% CI, 1.10-1.52). However, we have detected a significant sex-related interaction when analyzing the results. A significant relationship between vitamin D deficiency and NAFLD was found in men (aOR, 1.33; 95% CI, 1.11-1.60) but not in women.

Lifestyle and Dietary Factors Associated with Serum 25-Hydroxyvitamin D Levels in Korean Young Adults.

Inadequate vitamin D status is highly prevalent in the Korean population, especially among young adults. Nonetheless, correlates of suboptimal vitamin D levels in young adults are not well defined. This study aimed to investigate potentially modifiable determinants of vitamin D levels in young adults in Korea. This cross-sectional study was based on health check-up data from 3,450 healthy male and female university students aged 18-29 yr in Seoul between April and May 2013. Serum 25-hydroxyvitamin D [25(OH)D] levels were determined using chemiluminescent immunoassay. Anthropometric data were measured, and lifestyle, dietary, and sociodemographic factors were obtained through self-administered questionnaires. General linear regression was used to assess correlates of serum 25(OH)D levels. The mean serum 25(OH)D level was 11.1 ng/mL, and the prevalence of 25(OH)D levels less than 10 ng/mL was 44.7% (39.5% in men, 50.2% in women). In a final multivariable model, significant positive correlates of serum 25(OH)D were older age, male sex, increased physical activity, sunlight exposure ≥ 30 min/day, eating breakfast regularly, consumption of dairy and fatty fish, and use of vitamin D-containing supplements. In contrast, significant inverse correlates were obesity (body mass index, BMI ≥ 25 kg/m(2)) or underweight (BMI < 18.5 kg/m(2)), abdominal obesity, increased sedentary time, and frequent consumption of instant noodles and sugar-sweetened beverages. In conclusion, many modifiable lifestyle and dietary factors were associated with low serum 25(OH)D levels in Korean young adults. Further studies on potential mechanisms of the correlates and optimal strategies to improve vitamin D status in this vulnerable subpopulation are warranted.

Trends in underweight and severe underweight disparities in Korean adults and older adults: a nationwide, repeated cross-sectional study.

OBJECTIVES: Little is known about the disparities in underweight prevalence among the general population in high-income countries. We investigated the trends in underweight prevalence and disparities across sociodemographic groups among Korean adults and older adults. SETTING AND PARTICIPANTS: A series of cross-sectional data on Korean national health checkups for adults aged ≥20 years were analyzed from 2005 to 2016. MEASUREMENTS: Based on body mass index (kg/m2), underweight was graded as mild (17.0-18.49), moderate (16.0-16.9), and severe (<16.0). Underweight prevalence was compared across sociodemographic subgroups in 2015-2016. Trends in underweight disparities were examined from 2005-2006 to 2015-2016. Multivariable-adjusted odds ratios (ORs; 95% confidence intervals, CIs) were calculated using logistic regression. RESULTS: Approximately 11-22 million adults were included in each wave. In 2015-2016, the overall prevalence of underweight was 3.6% (men 2.0%, women 5.2%); severe underweight was 0.2% (men 0.1%, women 0.3%). The prevalence of underweight varied by sex and age groups. In men, those aged ≥80 years had the highest prevalence (overall 7.33%, severe underweight 0.84%). In women, those aged 20-29 years had the highest prevalence of overall underweight (14.57%), whereas those aged ≥80 years had the highest prevalence of severe underweight (1.38%). Compared with individuals in the lowest income quartile, men in the highest income had lower ORs of overall (0.59, 95% CI 0.59-0.60) and severe underweight (0.46, 95% CI 0.44-0.48); women in the highest income quartile had a higher OR of overall (1.12, 95% CI 1.12-1.13) but a lower OR of severe underweight (0.89, 95% CI 0.86-0.92). From 2005-2006 to 2015-2016, severe underweight consistently declined in older men but remained constant in women aged ≥80 years, widening sex disparities among older adults. Severe underweight decreased or leveled off in the highest income quartile but steadily increased in the lowest quartile, worsening income disparities. CONCLUSION: In this nationwide study, underweight was more prevalent among women, older adults aged ≥80 years, and low-income individuals. Disparities in severe underweight widened across sociodemographic subgroups over time.

Nutrients related to one-carbon metabolism and risk of renal cell cancer.

PURPOSE: Folate, vitamins B6 and B12, methionine, choline, and betaine are nutrients related to one-carbon metabolism and have been hypothesized to decrease cancer risk. Few studies have evaluated dietary intakes of these nutrients in relation to renal cell cancer (RCC). METHODS: We conducted prospective follow-up studies of women in the Nurses' Health Study and men in the Health Professionals Follow-up Study. Diet was assessed repeatedly using a validated semi-quantitative food-frequency questionnaire in both studies. RESULTS: During follow-up of 24 years among 77,208 women (918,891 person-years) and 22 years among 47,886 men (1,731,752 person-years), we accrued 436 cases of RCC (225 women and 211 men). Intakes of folate, vitamins B6 and B12, methionine, and betaine were not found to be related to RCC risk. Higher intake of free choline, but not other forms of choline, was associated with reduced RCC risk. The results were similar in men and women. CONCLUSIONS: We found little evidence that higher intakes of nutrients related to one-carbon metabolism lower RCC risk. One-carbon metabolism may have little influence on renal carcinogenesis.

Association between breakfast frequency and metabolic syndrome among young adults in South Korea.

Skipping breakfast is highly prevalent but it is not clear whether breakfast frequency is associated with metabolic syndrome in young adults. We aimed to assess the association between breakfast frequency and metabolic syndrome in Korean young adults. This cross-sectional study was based on health check-up data of university students aged 18-39 years between 2016 and 2018. Participants were stratified into three groups by breakfast frequency (non-skipper, skipper 1-3 days/week, skipper 4-7 days/week). Multivariable-adjusted logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of metabolic syndrome. Out of 12,302 participants, 56.8% skipped breakfast at least 4 days/week. Metabolic syndrome prevalence was higher in those skipping breakfast for 4 or more days/week compared to non-skipper. (3.1% vs 1.7%) In the age- and sex-adjusted model, individuals skipping breakfast for 4-7 days per week had a higher OR of metabolic syndrome (OR 1.73, 95% CI 1.21-2.49) compared to non-skipper. Although this association became insignificant (OR 1.49, 95% CI 0.99-2.23) after a fully adjusted multivariable model, trends of positive association between frequency of breakfast skipping and metabolic syndrome was significant (P for trend = 0.038). Frequent breakfast skipping was associated with higher odds of metabolic syndrome in young adults. Further longitudinal studies in the long term are needed to understand the association of meal patterns with metabolic syndrome.

Fructose consumption from different food sources and cardiometabolic biomarkers: cross-sectional associations in US men and women.

BACKGROUND: Previous studies on the relationship between fructose intake and cardiometabolic biomarkers have yielded inconsistent results, and the metabolic effects of fructose are likely to vary across food sources such as fruit versus sugar-sweetened beverages (SSB). OBJECTIVES: We aimed to examine associations of fructose from 3 major sources (SSB, fruit juice, and fruit) with 14 insulinemic/glycemic, inflammatory, and lipid markers. METHODS: We utilized cross-sectional data from 6858 men in the Health Professionals Follow-up Study, 15,400 women in NHS, and 19,456 women in NHSII who were free of type 2 diabetes, CVDs, and cancer at blood draw. Fructose intake was assessed via a validated FFQ. Multivariable linear regression was used to estimate the percentage differences of biomarker concentrations according to fructose intake. RESULTS: We found a 20 g/d increase in total fructose intake was associated with 1.5%- 1.9% higher concentrations of proinflammatory markers plus 3.5% lower adiponectin, as well as 5.9% higher TG/HDL cholesterol ratio. Unfavorable profiles of most biomarkers were only associated with fructose from SSB and juice. In contrast, fruit fructose was associated with lower concentrations of C-peptide, CRP, IL-6, leptin, and total cholesterol. Substituting 20 g/d fruit fructose for SSB fructose was associated with 10.1% lower C-peptide, 2.7%-14.5% lower proinflammatory markers and 1.8%-5.2% lower blood lipids. CONCLUSIONS: Beverage fructose intake was associated with adverse profiles of multiple cardiometabolic biomarkers.

Long-term Weight Training and Mortality in U.S. Male Health Professionals With and Without Type 2 Diabetes.

OBJECTIVE: To investigate the relationship between long-term weight training and mortality in male health professionals with and without type 2 diabetes. RESEARCH DESIGN AND METHODS: We analyzed 31,140 men without type 2 diabetes and 2,588 with type 2 diabetes from the Health Professionals Follow-up Study (1992-2018). Information on weight training was repeatedly assessed using a biennial questionnaire. Cox regression was used to estimate hazard ratios (HRs) and 95% CIs. RESULTS: During up to 26 years of follow-up, we documented 12,607 deaths (988 deaths among men with type 2 diabetes). Among participants without type 2 diabetes, 1-59 and 60-149 min/week of long-term weight training were associated with 14% (HR 0.86; 95% CI 0.82-0.89) and 8% (HR 0.92; 95% CI 0.85-0.99) lower mortality versus no weight training, respectively, after adjustment for aerobic activity. However, ≥150 min/week of weight training was not significantly associated with mortality (HR 1.05; 95% CI 0.91-1.20; overall P trend = 0.94; P quadratic < 0.001). Meeting the recommended aerobic physical activity guideline (≥150 min/week) and performing any weight training were associated with 20-34% lower mortality. Among participants with type 2 diabetes, a moderate level of pre-diagnosis weight training was associated with lower mortality, whereas post-diagnosis weight training showed no association. Performing both weight training and aerobic activity before and after diagnosis was associated with lower mortality. CONCLUSIONS: A moderate level of long-term weight training was associated with lower mortality, independently of aerobic activity, among male health professionals with and without type 2 diabetes. Addition of weight training to aerobic activities may provide further benefit in mortality risk reduction. Studies are required to confirm our findings in diverse populations.

Association of underweight status with the risk of tuberculosis: a nationwide population-based cohort study.

In studies evaluating the association between body mass index (BMI) and risk of tuberculosis (TB), the data for the underweight population has been limited and results were conflicting. Our study aimed to evaluate whether being underweight increases the risk of TB using a nationwide representative sample from the Republic of Korea. A large population-based cohort study of over ten million subjects who participated in the health screening in 2010 was performed using the Korean National Health Insurance database 2010-2017. We evaluated the incidence and risk of TB by BMI category (kg/m2) for Asians using a multivariable Cox regression model, adjusting for age, sex, smoking, alcohol consumption, regular exercise, low-income state, and underlying hypertension, diabetes mellitus, and dyslipidemia. To evaluate the association between BMI and TB risk, the underweight population was further subdivided according to the degree of thinness. During 70,063,154.3 person-years of follow-up, 52,615 of 11,135,332 individuals developed active TB with an incidence of 0.75 per 1000 person-years. Overall, there was a log-linear inverse relationship between TB incidence and BMI, within the BMI range of 15-30 kg/m2 (R2 = 0.95). The estimated adjusted hazard ratio (HR) for incident TB in the underweight population (BMI < 18.5) was 2.08 (95% confidence intervals, CI 2.02-2.15), overweight (23 ≤ BMI < 25) was 0.56 (0.55-0.58) and obese (BMI ≥ 25) was 0.40 (0.39-0.41) relative to the normal weight population. Among the underweight population, TB risk increased as the degree of thinness increased (adjusted HR = 1.98, 1.91-2.05; 2.50, 2.33-2.68; and 2.83, 2.55-3.15, for mild, moderate and severe thinness, respectively) (p for trend < 0.001). We found a significant inverse relationship between BMI and TB incidence, which was especially profound in the underweight population. Public health strategies to screen TB more actively in the underweight population and improve their weight status may help reduce the burden of TB.

Sugar-sweetened beverage and sugar consumption and colorectal cancer incidence and mortality according to anatomic subsite.

BACKGROUND: Recent preclinical research strongly suggests that dietary sugars can enhance colorectal tumorigenesis by direct action, particularly in the proximal colon that unabsorbed fructose reaches. OBJECTIVES: We aimed to examine long-term consumption of sugar-sweetened beverages (SSBs) and total fructose in relation to incidence and mortality of colorectal cancer (CRC) by anatomic subsite. METHODS: We followed 121,111 participants from 2 prospective US cohort studies, the Nurses' Health Study (1984-2014) and Health Professionals Follow-Up Study (1986-2014), for incident CRC and related death. Cox proportional hazards regression was used to compute HRs and 95% CIs. RESULTS: During follow-up, we documented 2733 incident cases of CRC with a known anatomic location, of whom 901 died from CRC. Positive associations of SSB and total fructose intakes with cancer incidence and mortality were observed in the proximal colon but not in the distal colon or rectum (Pheterogeneity ≤ 0.03). SSB consumption was associated with a statistically significant increase in the incidence of proximal colon cancer (HR per 1-serving/d increment: 1.18; 95% CI: 1.03, 1.34; Ptrend = 0.02) and a more pronounced elevation in the mortality of proximal colon cancer (HR: 1.39; 95% CI: 1.13, 1.72; Ptrend = 0.002). Similarly, total fructose intake was associated with increased incidence and mortality of proximal colon cancer (HRs per 25-g/d increment: 1.18; 95% CI: 1.03, 1.35; and 1.42; 95% CI: 1.12, 1.79, respectively). Moreover, SSB and total fructose intakes during the most recent 10 y, rather than those from a more distant period, were associated with increased incidence of proximal colon cancer. CONCLUSIONS: SSB and total fructose consumption were associated with increased incidence and mortality of proximal colon cancer, particularly during later stages of tumorigenesis.

Comparison of Two Strategies to Increase Serum Vitamin D Levels in a Real-World Setting: Sunlight Exposure and Oral Supplementation.

Sunlight exposure and oral supplementation are the key strategies to increase serum 25-hydroxyvitamin D [25(OH)D] concentration. We aimed to determine elevation in serum 25(OH)D levels by comparing sunlight exposure and oral vitamin D supplementation in vitamin D-deficient participants who chose the treatment strategy by shared decision-making. We enrolled 197 participants aged ≥19 y who had vitamin D deficiency (serum 25(OH)D<20 ng/mL). Participants selected their treatment method through shared decision-making by preference: sunlight exposure or 1,000 IU oral vitamin D3 supplementation daily. Changes in serum 25(OH)D concentration and duration of sunlight exposure were evaluated after 3 mo. Among 197 participants, 26 (13%) selected sunlight exposure and 171 (87%) selected oral vitamin D supplementation. Seasonal distribution of participants and follow-up rate after 3 mo were not significantly different. There was no significant increase in mean serum 25(OH)D levels in the sunlight exposure group. Conversely, the mean serum 25(OH)D level increased by 11 ng/mL after 3 mo in the oral vitamin D supplementation group. The duration of mean sunlight exposure per day during the study period was not significantly different between the groups. Oral supplementation with 1,000 IU vitamin D3 daily significantly increased serum 25(OH)D levels in vitamin D-deficient participants after 3 mo, while sunlight exposure did not. This study suggests that oral supplementation is more effective than sun exposure in increasing vitamin D levels in the Korean population. Therefore, new recommendations on maintaining adequate vitamin D levels are needed in the Korean population.

Incidence of cardiovascular disease and mortality in underweight individuals.

BACKGROUND: Few studies have evaluated the association between being underweight and having cardiovascular disease in the general population. We investigated the incidence of stroke, myocardial infarction (MI), and all-cause mortality according to detailed underweight categories in a large population cohort. METHODS: We included 4 164 364 individuals who underwent a health examination that was conducted as part of the Korean National Health Insurance Service between January 2009 and December 2012 and followed them up to determine the incidence of stroke, MI, and all-cause mortality until 31 December 2016. Based on the body mass index, the study population was categorized into normal (18.50-22.99), mild (17.00-18.49), moderate (16.00-16.99), and severe underweight (<16.00) groups. Cox proportional hazards analyses were performed to calculate the hazard ratio for stroke, MI, and mortality according to the severity of underweight in reference to the normal weight. We adjusted for age, sex, lifestyle, economic status, co-morbidity, blood pressure, glucose, lipid level, and waist circumference. RESULTS: The mean age of the 4 164 364 eligible subjects in this study cohort was 44.4 ± 14.3 years, and 46.1% of the participants were male; 46 728 strokes, 30 074 MIs, and 121 080 deaths occurred during 27 449 902 person-years. The incidence of stroke, MI, and all-cause mortality increased proportionally with the severity of underweight in the multivariate model. This proportional association became more evident when the waist circumference was additionally adjusted. The respective hazard ratios (95% confidence intervals) for mild, moderate, and severe underweight were 1.10 (1.06-1.15), 1.11 (1.02-1.20), and 1.38 (1.24-1.53) for stroke; 1.19 (1.14-1.25), 1.40 (1.27-1.53), and 1.86 (1.64-2.11) for MI; and 1.63 (1.60-1.67), 2.10 (2.02-2.17), and 2.98 (2.85-3.11) for all-cause mortality. In stratified analyses based on waist circumference, the severity of underweight was consistently associated with a higher risk of stroke, MI, and death. CONCLUSIONS: The severity of underweight was associated with a higher risk of stroke, MI, and all-cause mortality.

Effect of sun exposure versus oral vitamin D supplementation on serum 25-hydroxyvitamin D concentrations in young adults: A randomized clinical trial.

BACKGROUND: Vitamin D inadequacy is associated with a wide range of diseases. However, optimal strategies to improve vitamin D status, especially in Asian populations, remain unclear. We tested the hypotheses that (1) relevant sun exposure or oral vitamin D supplementation would significantly increase serum 25-hydroxyvitamin D (25OHD) concentrations compared with placebo, (2) sun exposure and supplementary vitamin D would be similar in serum 25OHD increases, and (3) the two interventions may have different effects on cardio-metabolic markers. METHODS: In this 8-week randomized placebo-controlled clinical trial including vitamin D-deficient adults in Seoul (37 °N), Korea, changes in serum 25OHD concentrations were compared between the sun exposure (daily ≥20-30 min around noon, n = 50), oral vitamin D3 (500 IU/d, n = 50), and control (placebo, n = 50) groups. RESULTS: Both sun exposure and oral vitamin D3 effectively increased serum 25OHD concentrations. Compared with placebo, the between-group least-squares mean (LSM) differences in changes were 2.2 ng/mL (95% CI: 0.2, 4.2) in the sun exposure group and 8.5 ng/mL (6.5, 10.5) in the oral vitamin D3 group. Increases in serum 25OHD were greater with oral vitamin D3 than with sun exposure (LSM difference in changes = 6.3 ng/mL, 95% CI: 4.3, 8.3). More participants in the oral vitamin D3 group (54.2%) achieved serum 25OHD concentrations ≥20 ng/mL at week 8 than those in the sun exposure (12.2%) or control (4.3%) groups. Compliance with sun exposure advice was relatively low, and only those with adequate compliance had a significant increase in serum 25OHD. Changes in the cardio-metabolic markers were mostly insignificant in all groups. CONCLUSIONS: Enhanced sun exposure and 500 IU/d of oral vitamin D3 supplementation significantly increased serum 25OHD concentrations. However, our protocol for sun exposure was not as effective as 500 IU/d of oral vitamin D3 supplementation. This trial was registered at clinicaltrials.gov as NCT03310242.

Predictors of long-term smoking cessation among smokers enrolled in a university smoking cessation program: A longitudinal study.

Many lifelong smokers establish smoking habits during young adulthood. A university can be an effective setting for early smoking cessation. We evaluated long-term predictors of smoking cessation among smokers in a university setting.We longitudinally followed a cohort of smokers enrolled in a university smoking cessation program in Seoul, South Korea. Sociodemographic factors, smoking-related variables, and changes in smoking habits were assessed during 6-week visit sessions and follow-up telephone interviews conducted 1 year or more later.A total of 205 participants were followed up (mean follow-up duration: 27.1 months). Cessation rates were 47.3% at the end of the visit sessions and 28.8% at follow-up. The long-term persistent smoking rate was significantly higher among individuals with peers who smoked (odds ratio [OR] = 8.64; 95% confidence interval [CI] = 1.75, 42.80), with family members who smoked (OR = 3.28; 95% CI = 1.20, 9.00), and who smoked 10 to 19 cigarettes/day (OR = 4.83; 95% CI = 1.49, 15.69). Conversely, persistent smoking was less likely among those who attended the program regularly (OR = 0.84 per visit; 95% CI = 0.72, 0.99) and attempted quitting more frequently (OR = 0.93 per attempt; 95% CI = 0.87, 0.99). Use of smoking cessation medications (varenicline or bupropion) was not significantly associated with long-term quitting (OR = 0.71; 95% CI = 0.26, 1.93).Peer influences were the strongest predictors of failure in long-term cessation among smokers who attempted to quit. Similarly, the existence of smokers in the family was negatively associated with successful quitting. Regular attendance at a smoking cessation program and a high number of attempts to quit were positively associated with successful quitting. Targeting peer and family smoking groups together rather than targeting individual smokers alone, implementing active cessation programs encouraging regular attendance, and providing comprehensive antismoking environments might be effective strategies in a university setting.