A Randomized Trial Comparing the Specific Carbohydrate Diet to a Mediterranean Diet in Adults With Crohn's Disease.

BACKGROUND & AIMS: This study compared the effectiveness of the Specific Carbohydrate Diet (SCD) to the Mediterranean diet (MD) as treatment for Crohn's disease (CD) with mild to moderate symptoms. METHODS: Adult patients with CD and with mild-to-moderate symptoms were randomly assigned 1:1 to consume the MD or SCD for 12 weeks. For the first 6 weeks, participants received prepared meals and snacks according to their assigned diet. After 6 weeks, participants were instructed to follow the diet independently. The primary outcome was symptomatic remission at week 6. Key secondary outcomes at week 6 included fecal calprotectin (FC) response (FC <250 µg/g and reduction by >50% among those with baseline FC >250 µg/g) and C-reactive protein (CRP) response (high-sensitivity CRP <5 mg/L and >50% reduction from baseline among those with high-sensitivity CRP >5 mg/L). RESULTS: The study randomized 194 patients, and 191 were included in the efficacy analyses. The percentage of participants who achieved symptomatic remission at week 6 was not superior with the SCD (SCD, 46.5%; MD, 43.5%; P = .77). FC response was achieved in 8 of 23 participants (34.8%) with the SCD and in 4 of 13 participants (30.8%) with the MD (P = .83). CRP response was achieved in 2 of 37 participants (5.4%) with the SCD and in 1 of 28 participants (3.6%) with the MD (P = .68). CONCLUSIONS: The SCD was not superior to the MD to achieve symptomatic remission, FC response, and CRP response. CRP response was uncommon. Given these results, the greater ease of following the MD and other health benefits associated with the MD, the MD may be preferred to the SCD for most patients with CD with mild to moderate symptoms. ClinicalTrials.gov Identifier: NCT03058679.

Coronary Artery Calcification and Risk of Cardiovascular Disease and Death Among Patients With Chronic Kidney Disease.

Importance: Coronary artery calcification (CAC) is highly prevalent in dialysis-naive patients with chronic kidney disease (CKD). However, there are sparse data on the association of CAC with subsequent risk of cardiovascular disease and all-cause mortality in this population. Objective: To study the prospective association of CAC with risk of cardiovascular disease and all-cause mortality among dialysis-naive patients with CKD. Design, Setting, and Participants: The prospective Chronic Renal Insufficiency Cohort study recruited adults with an estimated glomerular filtration rate of 20 to 70 mL/min/1.73 m2 from 7 clinical centers in the United States. There were 1541 participants without cardiovascular disease at baseline who had CAC scores. Exposures: Coronary artery calcification was assessed using electron-beam or multidetector computed tomography. Main Outcomes and Measures: Incidence of cardiovascular disease (including myocardial infarction, heart failure, and stroke) and all-cause mortality were reported every 6 months and confirmed by medical record adjudication. Results: During an average follow-up of 5.9 years in 1541 participants aged 21 to 74 years, there were 188 cardiovascular disease events (60 cases of myocardial infarction, 120 heart failures, and 27 strokes; patients may have had >1 event) and 137 all-cause deaths. In Cox proportional hazards models adjusted for age, sex, race, clinical site, education level, physical activity, total cholesterol level, high-density lipoprotein cholesterol level, systolic blood pressure, use of antihypertensive treatment, current cigarette smoking, diabetes status, body mass index, C-reactive protein level, hemoglobin A1c level, phosphorus level, troponin T level, log N-terminal pro-B-type natriuretic peptide level, fibroblast growth factor 23 level, estimated glomerular filtration rate, and proteinuria, the hazard ratios associated with per 1 SD log of CAC were 1.40 (95% CI, 1.16-1.69; P < .001) for cardiovascular disease, 1.44 (95% CI, 1.02-2.02; P = .04) for myocardial infarction, 1.39 (95% CI, 1.10-1.76; P = .006) for heart failure, and 1.19 (95% CI, 0.94-1.51; P = .15) for all-cause mortality. In addition, inclusion of CAC score led to an increase in the C statistic of 0.02 (95% CI, 0-0.09; P < .001) for predicting cardiovascular disease over use of all the above-mentioned established and novel cardiovascular disease risk factors. Conclusions and Relevance: Coronary artery calcification is independently and significantly related to the risks of cardiovascular disease, myocardial infarction, and heart failure in patients with CKD. In addition, CAC improves risk prediction for cardiovascular disease, myocardial infarction, and heart failure over use of established and novel cardiovascular disease risk factors among patients with CKD; however, the changes in the C statistic are small.

Inflammation and elevated levels of fibroblast growth factor 23 are independent risk factors for death in chronic kidney disease.

Inflammation is a consequence of chronic kidney disease (CKD) and is associated with adverse outcomes in many clinical settings. Inflammation stimulates production of fibroblast growth factor 23 (FGF23), high levels of which are independently associated with mortality in CKD. Few large-scale prospective studies have examined inflammation and mortality in patients with CKD, and none tested the interrelationships among inflammation, FGF23, and risk of death. Therefore, we conducted a prospective investigation of 3875 participants in the Chronic Renal Insufficiency Cohort (CRIC) study with CKD stages 2 to 4 to test the associations of baseline plasma interleukin-6, high-sensitivity C-reactive protein, and FGF23 levels with all-cause mortality, censoring at the onset of end-stage renal disease. During a median follow-up of 6.9 years, 550 participants died (20.5/1000 person-years) prior to end-stage renal disease. In separate multivariable-adjusted analyses, higher levels of interleukin-6 (hazard ratio per one standard deviation increase of natural log-transformed levels) 1.35 (95% confidence interval, 1.25-1.46), C-reactive protein 1.28 (1.16-1.40), and FGF23 1.45 (1.32-1.60) were each independently associated with increased risk of death. With further adjustment for FGF23, the risks of death associated with interleukin-6 and C-reactive protein were minimally attenuated. Compared to participants in the lowest quartiles of inflammation and FGF23, the multivariable-adjusted hazard ratio of death among those in the highest quartiles of both biomarkers was 4.38 (2.65-7.23) for interleukin-6 and FGF23, and 5.54 (3.04-10.09) for C-reactive protein and FGF23. Thus, elevated levels of interleukin-6, C-reactive protein, and FGF23 are independent risk factors for mortality in CKD.

The Associations between Peripheral Artery Disease and Physical Outcome Measures in Men and Women with Chronic Kidney Disease.

BACKGROUND: Peripheral artery disease (PAD) is highly prevalent and associated with significant morbidity and mortality, but sex-based differences are incompletely understood. We sought to define the associations between PAD and physical outcome measures and to determine if these associations differed by sex in the Chronic Renal Insufficiency Cohort. METHODS: Among 3,543 participants, we assessed the cross-sectional relationship between PAD severity defined by ankle-brachial index; and (1) physical activity (metabolic equivalent [MET]-hr/wk), (2) walking pace (slow versus medium and/or fast), and (3) physical function (12-item Short Form Health Survey [SF-12]) at baseline. RESULTS: In a multivariable linear regression model, PAD severity was not associated with physical activity defined by total MET-hr per wk in men or women (P = 0.432). However, PAD severity was significantly associated with walking activity (P = 0.037), although this relationship did not differ by sex (P = 0.130). Similarly, PAD severity was significantly associated with walking pace (P < 0.001), although this relationship did not differ by sex (P = 0.086). In contrast, there was an independent association between PAD severity and SF-12 (P = 0.018), with a significant interaction by sex (P < 0.001). CONCLUSIONS: These data suggest that tools used to evaluate the functional consequences of PAD should focus on walking activity and walking pace, as well as physical function, where sex-specific associations should be accounted for.

Traditional and non-traditional risk factors for incident peripheral arterial disease among patients with chronic kidney disease.

BACKGROUND: The risk of peripheral arterial disease (PAD) is higher in patients with chronic kidney disease (CKD) compared with those without. However, reasons for this increased risk are not fully understood. METHODS: We studied risk factors for incident PAD among 3169 participants in the Chronic Renal Insufficiency Cohort (CRIC) Study. Patients with CKD aged 21-74 years were recruited between 2003 and 2008 and followed for a median of 6.3 years. Incident PAD was defined as a new onset ankle-brachial index (ABI) of <0.9 or confirmed clinical PAD. RESULTS: In a multivariate-adjusted model, older age, female sex, non-Hispanic Black, current smoking, diabetes, higher pulse pressure, lower high-density lipoprotein cholesterol, higher low-density lipoprotein cholesterol, and lower estimated glomerular filtration rate were significantly associated with the increased risk of incident PAD. After adjustment for these traditional risk factors as well as use of medications and CRIC Study clinic sites, the following baseline novel risk factors were significantly associated with risk of incident PAD [hazard ratio and 95% confidence interval (CI) for a one standard deviation (SD) higher level]: log[C-reactive protein (CRP)] (1.16, 1.06-1.25, P < 0.001), white blood cell count (1.09, 1.01-1.18, P = 0.03), fibrinogen (1.15, 1.06-1.26, P = 0.002), log(myeloperoxidase) (1.12, 1.03-1.23, P = 0.01), uric acid (0.88, 0.80-0.97, P = 0.01), glycated hemoglobin (1.16, 1.05-1.27, P = 0.003), log(homeostatic model assessment-insulin resistance) (1.21, 1.10-1.32, P < 0.001) and alkaline phosphatase (1.15, 1.07-1.24, P < 0.001). CONCLUSIONS: Among patients with CKD, inflammation, prothrombotic state, oxidative stress, glycated hemoglobin, insulin resistance and alkaline phosphatase are associated with an increased risk of PAD, independent of traditional risk factors.

Inflammation, Antibiotics, and Diet as Environmental Stressors of the Gut Microbiome in Pediatric Crohn's Disease.

Abnormal composition of intestinal bacteria--"dysbiosis"-is characteristic of Crohn's disease. Disease treatments include dietary changes and immunosuppressive anti-TNFα antibodies as well as ancillary antibiotic therapy, but their effects on microbiota composition are undetermined. Using shotgun metagenomic sequencing, we analyzed fecal samples from a prospective cohort of pediatric Crohn's disease patients starting therapy with enteral nutrition or anti-TNFα antibodies and reveal the full complement and dynamics of bacteria, fungi, archaea, and viruses during treatment. Bacterial community membership was associated independently with intestinal inflammation, antibiotic use, and therapy. Antibiotic exposure was associated with increased dysbiosis, whereas dysbiosis decreased with reduced intestinal inflammation. Fungal proportions increased with disease and antibiotic use. Dietary therapy had independent and rapid effects on microbiota composition distinct from other stressor-induced changes and effectively reduced inflammation. These findings reveal that dysbiosis results from independent effects of inflammation, diet, and antibiotics and shed light on Crohn disease treatments.

Pioglitazone Use and Risk of Bladder Cancer and Other Common Cancers in Persons With Diabetes.

IMPORTANCE: Studies suggest pioglitazone use may increase risk of cancers. OBJECTIVE: To examine whether pioglitazone use for diabetes is associated with risk of bladder and 10 additional cancers. DESIGN, SETTING, AND PARTICIPANTS: Cohort and nested case-control analyses among persons with diabetes. A bladder cancer cohort followed 193,099 persons aged 40 years or older in 1997-2002 until December 2012; 464 case patients and 464 matched controls were surveyed about additional confounders. A cohort analysis of 10 additional cancers included 236,507 persons aged 40 years or older in 1997-2005 and followed until June 2012. Cohorts were from Kaiser Permanente Northern California. EXPOSURES: Ever use, duration, cumulative dose, and time since initiation of pioglitazone as time dependent. MAIN OUTCOMES AND MEASURES: Incident cancer, including bladder, prostate, female breast, lung/bronchus, endometrial, colon, non-Hodgkin lymphoma, pancreas, kidney/renal pelvis, rectum, and melanoma. RESULTS: Among 193,099 persons in the bladder cancer cohort, 34,181 (18%) received pioglitazone (median duration, 2.8 years; range, 0.2-13.2 years) and 1261 had incident bladder cancer. Crude incidences of bladder cancer in pioglitazone users and nonusers were 89.8 and 75.9 per 100,000 person-years, respectively. Ever use of pioglitazone was not associated with bladder cancer risk (adjusted hazard ratio [HR], 1.06; 95% CI, 0.89-1.26). Results were similar in case-control analyses (pioglitazone use: 19.6% among case patients and 17.5% among controls; adjusted odds ratio, 1.18; 95% CI, 0.78-1.80). In adjusted analyses, there was no association with 8 of the 10 additional cancers; ever use of pioglitazone was associated with increased risk of prostate cancer (HR, 1.13; 95% CI, 1.02-1.26) and pancreatic cancer (HR, 1.41; 95% CI, 1.16-1.71). Crude incidences of prostate and pancreatic cancer in pioglitazone users vs nonusers were 453.3 vs 449.3 and 81.1 vs 48.4 per 100,000 person-years, respectively. No clear patterns of risk for any cancer were observed for time since initiation, duration, or dose. CONCLUSIONS AND RELEVANCE: Pioglitazone use was not associated with a statistically significant increased risk of bladder cancer, although an increased risk, as previously observed, could not be excluded. The increased prostate and pancreatic cancer risks associated with ever use of pioglitazone merit further investigation to assess whether they are causal or are due to chance, residual confounding, or reverse causality.

Comparative Effectiveness of Nutritional and Biological Therapy in North American Children with Active Crohn's Disease.

BACKGROUND: Therapeutic targets in pediatric Crohn's disease include symptoms, quality of life (QOL), and mucosal healing. Although partial enteral nutrition (PEN), exclusive enteral nutritional (EEN), and anti-tumor necrosis factor alpha (anti-TNF) therapy all improve symptoms, the comparative effectiveness of these approaches to improve QOL and achieve mucosal healing has not been assessed prospectively. METHODS: In a prospective study of children initiating PEN, EEN, or anti-TNF therapy for Crohn's disease, we compared clinical outcomes using the Pediatric Crohn's Disease Activity Index (PCDAI), QOL (IMPACT score), and mucosal healing as estimated by fecal calprotectin (FCP). PCDAI, IMPACT, FCP, and diet (prompted 24-h recall) were measured at baseline and after 8 weeks of therapy. RESULTS: We enrolled 90 children with active Crohn's disease (PCDAI, 33.7 ± 13.7; and FCP, 976 ± 754), of whom 52 were treated with anti-TNF, 22 with EEN, and 16 with PEN plus ad lib diet. Clinical response (PCDAI reduction ≥15 or final PCDAI ≤10) was achieved by 64% on PEN, 88% EEN, and 84% anti-TNF (test for trend P = 0.08). FCP ≤250 µg/g was achieved with PEN in 14%, EEN 45%, and anti-TNF 62% (test for trend P = 0.001). Improvement in overall QOL was not statistically significantly different between the 3 groups (P = 0.86). However, QOL improvement was the greatest with EEN in the body image (P = 0.03) domain and with anti-TNF in the emotional domain (P = 0.04). CONCLUSIONS: Although PEN improved clinical symptoms, EEN and anti-TNF were more effective for decreasing mucosal inflammation and improving specific aspects of QOL.

Healthy lifestyle and risk of kidney disease progression, atherosclerotic events, and death in CKD: findings from the Chronic Renal Insufficiency Cohort (CRIC) Study.

BACKGROUND: In general populations, healthy lifestyle is associated with fewer adverse outcomes. We estimated the degree to which adherence to a healthy lifestyle decreases the risk of renal and cardiovascular events among adults with chronic kidney disease (CKD). STUDY DESIGN: Prospective cohort. SETTING & PARTICIPANTS: 3,006 adults enrolled in the Chronic Renal Insufficiency Cohort (CRIC) Study. PREDICTORS: 4 lifestyle factors (regular physical activity, body mass index [BMI] of 20-<25kg/m(2), nonsmoking, and "healthy diet"), individually and in combination. OUTCOMES: CKD progression (50% decrease in estimated glomerular filtration rate or end-stage renal disease), atherosclerotic events (myocardial infarction, stroke, or peripheral arterial disease), and all-cause mortality. MEASUREMENTS: Multivariable-adjusted Cox proportional hazards. RESULTS: During a median follow-up of 4 years, we observed 726 CKD progression events, 355 atherosclerotic events, and 437 deaths. BMI≥25kg/m(2) and nonsmoking were associated with reduced risk of CKD progression (HRs of 0.75 [95% CI, 0.58-0.97] and 0.61 [95% CI, 0.45-0.82] for BMIs of 25 to <30 and ≥30kg/m(2), respectively, versus 20 to <25kg/m(2); HR for nonsmoking of 0.68 [95% CI, 0.55-0.84] compared to the current smoker reference group) and reduced risk of atherosclerotic events (HRs of 0.67 [95% CI, 0.46-0.96] for BMI of 25-<30 vs 20-<25kg/m(2) and 0.55 [95% CI, 0.40-0.75] vs current smoker). Factors associated with reduced all-cause mortality were regular physical activity (HR, 0.64 [95% CI, 0.52-0.79] vs inactive), BMI≥30kg/m(2) (HR, 0.64 [95% CI, 0.43-0.96] vs 20-<25kg/m(2)), and nonsmoking (HR, 0.45 [95% CI, 0.34-0.60] vs current smoker). BMI<20kg/m(2) was associated with increased all-cause mortality risk (HR, 2.11 [95% CI, 1.13-3.93] vs 20-<25kg/m(2)). Adherence to all 4 lifestyle factors was associated with a 68% lower risk of all-cause mortality compared to adherence to no lifestyle factors (HR, 0.32; 95% CI, 0.11-0.89). LIMITATIONS: Lifestyle factors were measured only once. CONCLUSIONS: Regular physical activity, nonsmoking, and BMI≥25kg/m(2) were associated with lower risk of adverse outcomes in this cohort of individuals with CKD.

Proteinuria testing among patients with diabetes mellitus is associated with bladder cancer diagnosis: potential for unmeasured confounding in studies of pioglitazone and bladder cancer.

BACKGROUND: The observed association between pioglitazone and bladder cancer could be causal or because of bias in the design of prior studies. We hypothesize that proteinuria testing may lead to detection bias if routine test results for proteinuria lead to a full urinalysis. METHODS: We reanalyzed patients with diabetes mellitus within Kaiser Permanente Northern California. Logistic and Cox regression adjusted for age, sex, race, and smoking were used to assess the association of proteinuria testing with pioglitazone use, subsequent full urinalysis, and diagnosis with bladder cancer. RESULTS: Patients treated with pioglitazone were more likely than others with diabetes to undergo testing for proteinuria (p < 0.001). The odds of positive tests for proteinuria were higher among pioglitazone-treated patients (OR = 1.41, 95%CI 1.36-1.46). A positive proteinuria test was associated with increased odds of completing a urinalysis in the following 6 months (OR = 1.78, 95%CI 1.73-1.85). Negative and positive proteinuria test results were inversely (hazard ratio (HR) 0.63, 95%CI 0.52-0.75) and positively associated (HR 2.45, 95%CI 2.12-2.82) with bladder cancer risk, respectively. Adjustment for negative and positive proteinuria testing reduced the magnitude of association between pioglitazone and bladder cancer by only 5 to 10% (ever-exposed HR: from 1.06 to 1.01 and >4 years exposure HR: from 1.38 to 1.28). CONCLUSIONS: Proteinuria testing may be a confounder in studies of pioglitazone and bladder cancer but does not fully explain the association between pioglitazone and bladder cancer in this cohort. Optimal adjustment for proteinuria testing likely requires knowledge of the test result.

Risk of bladder cancer among diabetic patients treated with pioglitazone: interim report of a longitudinal cohort study.

OBJECTIVE: Some preclinical in vivo studies and limited human data suggest a possible increased risk of bladder cancer with pioglitazone therapy. This is an interim report of an ongoing cohort study examining the association between pioglitazone therapy and the risk of bladder cancer in patients with diabetes. RESEARCH DESIGN AND METHODS: This study includes 193,099 patients in the Kaiser Permanente Northern California diabetes registry who were ≥40 years of age between 1997 and 2002. Those with prior bladder cancer were excluded. Ever use of each diabetes medication (defined as two or more prescriptions within 6 months) was treated as a time-dependent variable. Cox regression-generated hazard ratios (HRs) compared pioglitazone use with nonpioglitazone use adjusted for age, sex, race/ethnicity, diabetes medications, A1C, heart failure, household income, renal function, other bladder conditions, and smoking. RESULTS: The group treated with pioglitazone comprised 30,173 patients. There were 90 cases of bladder cancer among pioglitazone users and 791 cases of bladder cancer among nonpioglitazone users. Overall, ever use of pioglitazone was not associated with risk of bladder cancer (HR 1.2 [95% CI 0.9-1.5]), with similar results in men and women (test for interaction P = 0.8). However, in the a priori category of >24 months of therapy, there was an increased risk (1.4 [1.03-2.0]). Ninety-five percent of cancers diagnosed among pioglitazone users were detected at early stage. CONCLUSIONS: In this cohort of patients with diabetes, short-term use of pioglitazone was not associated with an increased incidence of bladder cancer, but use for more than 2 years was weakly associated with increased risk.

Rosiglitazone for active ulcerative colitis: a randomized placebo-controlled trial.

BACKGROUND & AIMS: Thiazolidinedione ligands for the gamma subtype of peroxisome proliferator-activated receptors (PPARgamma), widely used to treat type 2 diabetes mellitus, have been proposed as novel therapies for ulcerative colitis (UC). METHODS: This multicenter, randomized, double-blind, placebo-controlled clinical trial compared the efficacy of rosiglitazone (Avandia; GlaxoSmithKline, Philadelphia, PA) 4 mg orally twice daily vs placebo twice daily for 12 weeks in 105 patients with mild to moderately active UC. Disease activity was measured with the Mayo score. The primary end point was clinical response (>/=2-point reduction) at week 12. Clinical remission (Mayo score