Assessment of high-throughput high-resolution MALDI-TOF-MS of urinary peptides for the detection of muscle-invasive bladder cancer

PURPOSE

There is a need for better biomarkers to both detect bladder cancer and distinguish muscle-invasive (stage T2+) from non-invasive (stage Ta/T1) disease. We assess whether MALDI-TOF-MS of the urine peptidome can achieve this.

EXPERIMENTAL DESIGN

We analysed urine from 751 patients with bladder cancer and 127 patients without bladder cancer. Endogenous peptide profiling was performed using a Bruker Ultraflextreme MALDI-TOF-MS.

RESULTS

Significant differences were seen between the spectra of urine from patients with and without T2+ disease. Albumin, total protein and haematuria were also elevated in T2+ patients. Haematuria was detected in 39% of patients with Ta/T1 disease and in 77% of patients with T2+ disease. Class prediction models based on MALDI data produced areas under receiver-operator characteristic curves of up to 0.76 but did not significantly outperform a model based on total protein alone. Many peptides significantly associated with invasive disease are fragments of abundant blood proteins and are also associated with haematuria.

CONCLUSIONS AND CLINICAL RELEVANCE

Microscopic haematuria is strongly associated with invasive disease; even traces of blood/plasma strongly influence the urinary peptidome. This needs to be taken into consideration when using 'omic' methods to search for urinary biomarkers as blood proteins may give false-positive results.

The diagnostic performance of scoring systems to identify symptomatic colorectal cancer compared to current referral guidance

OBJECTIVES

To determine the discrimination characteristics of a new algorithm and two existing symptom scoring systems for identification of patients with suspected colorectal cancer.

DESIGN

Derivation of algorithm by a case-control study and assessment of discrimination characteristics using receiver operating characteristics (ROC) curves. Three colorectal cancer scoring systems were investigated. The Bristol-Birmingham (BB) equation, which we derived from a large primary care dataset; the CAPER score, previously derived from a primary care case-control study and a symptom score derived from National Institute of Clinical Excellence (NICE) guidance for urgent referral of symptomatic patients. Their discrimination characteristics were investigated in two datasets: the BB derivation dataset and the CAPER score derivation dataset. The main analyses were ROC curves and the areas under them for all three algorithms in both datasets. Setting Electronic primary care databases. Main outcome measures Diagnosis of colorectal cancer.

RESULTS

In the BB dataset, areas under the curve were: BB equation 0.83 (95% CI 0.82 to 0.84); CAPER 0.79 (95% CI 0.79 to 0.80); the NICE guidelines 0.65 (95% CI 0.64 to 0.66). In the CAPER dataset, areas under the curve were: BB 0.92 (95% CI 0.91 to 0.94); CAPER 0.91 (95% CI 0.89 to 0.93); NICE guidelines 0.75 (95% CI 0.72 to 0.79). In subjects under 50 the discrimination characteristics of NICE referral guidelines were no better than chance.

CONCLUSIONS

Both multivariable symptom scoring systems performed significantly better than NICE referral guidelines.

Intergenerational influences on diabetes in a developing population: the Guangzhou Biobank Cohort Study

OBJECTIVES

Intergenerational "mismatch" and/or growth conditions may be relevant to the epidemic of diabetes in developing populations. In a rapidly developing southern Chinese population, we tested whether maternal environment, proxied by maternal literacy, or family socio-economic position (SEP), proxied by paternal literacy, were associated with fasting glucose and diabetes. To assess if intergenerational mismatch contributed, we tested whether the associations varied by life course SEP.

METHODS

In 19,818 older (≥50 years) adults from the Guangzhou Biobank Cohort Study (phases 2 and 3), we used censored and logistic regression to assess the associations of maternal and paternal literacy with fasting glucose, elevated fasting glucose and diabetes and whether these associations varied by sex, age or life course SEP.

RESULTS

Maternal, but not paternal, literacy was negatively associated with fasting plasma glucose (β-coefficient -0.06 mmol/l, 95% confidence interval (CI) -0.11 to -0.01) and elevated fasting glucose (odds ratio (OR) 0.92, 95% CI 0.86-0.99) adjusted for age, sex, study phase, life course SEP, childhood growth, adiposity, number of offspring, and birth order. Associations of maternal and paternal literacy with fasting glucose, elevated fasting glucose and diabetes did not vary by sex, age or life course SEP.

CONCLUSION

Offspring of literate mothers had lower risk for impaired glucose tolerance than offspring of illiterate mothers. Being raised by literate mothers may increase the likelihood of children with higher SEP and lower long-term disease risk, or better maternal conditions over generations may be associated with lower fasting glucose.

Alcohol consumption and aortic arch calcification in an older Chinese sample: the Guangzhou Biobank Cohort Study

OBJECTIVE

To examine the association between alcohol consumption and aortic arch calcification (AAC) in an older Chinese sample.

METHODS

In 27,844 older people aged 50-85, socioeconomic position and lifestyle factors were assessed by a questionnaire. The presence and severity of AAC were diagnosed from chest X-ray by two experienced radiologists.

RESULTS

In men, the risk for AAC increased significantly in frequent or excessive drinkers [adjusted odds ratio (OR)=1.36 (95% confidence interval (CI) 1.16-1.59) and 1.49 (1.21-1.83) for those who drank >5 times/week and those who drank excessively, respectively] (P for trend from 0.002 to 0.001). When AAC was analyzed as an outcome variable with 3 categories of severity, significant dose-response relations between the severity of AAC and alcohol consumption were observed, with those who drank frequently (>5/week) or excessively having more serious AAC (P for trend=0.03 and 0.02, respectively). No significant association was found in women as few drank excessively.

CONCLUSION

The presence and severity of AAC were associated with quantity or frequency of alcohol consumption in a dose-response pattern, suggesting that alcohol drinking, even when moderate, has no benefit for AAC. Excessive drinking increased the risk of AAC by 50% compared to never drinkers.

Life long endogenous estrogen exposure and later adulthood cognitive function in a population of naturally postmenopausal women from Southern China: the Guangzhou Biobank Cohort Study

BACKGROUND

Estrogen has neurotrophic and neuroprotective properties in animal and in vitro studies. Epidemiological studies are inconclusive, but suggest a positive association between endogenous estrogen exposure (measured by reproductive period, the number of years between menarche and menopause) and later life cognitive function.

METHODS

Structural equation modeling was used in a cross-sectional study of 11,094 naturally postmenopausal multiparous Chinese older (≥50 years) women from the Guangzhou Biobank Cohort Study (phases 2 and 3) to assess the interrelationship of four proxies of higher endogenous estrogen exposure (longer reproductive period, older age of first pregnancy, lower parity and shorter average duration of breast feeding per child) with immediate and the delayed 10-word recall score in phases 2 and 3, and with the mini-mental state examination (MMSE) score in phase 3 (5641 women).

RESULTS

Adjusted for age, education, childhood and adulthood socio-economic position and physical activity, longer reproductive period was associated with higher scores (0.02 words per year, 95% confidence interval (CI) 0.008-0.02 for delayed recall and 0.05 MMSE score, 95%CI 0.04-0.07, respectively). Lower parity and shorter average duration of breast-feeding per child were also associated with better cognitive function.

CONCLUSIONS

In a large cohort of naturally postmenopausal Chinese women proxies of greater endogenous estrogen exposure were associated with better cognitive function. These findings support biological evidence for a cognitively protective role of endogenous estrogen.

White blood cell subsets are associated with carotid intima-media thickness and pulse wave velocity in an older Chinese population: the Guangzhou Biobank Cohort Study

Cross-sectional associations between white blood cell (WBC) count, lymphocyte and granulocyte numbers, and carotid intima-media thickness (IMT) and brachial-ankle pulse wave velocity (PWV) were examined in a novel older Chinese community sample. A total of 817 men and 760 women from a sub-study of the Guangzhou Biobank Cohort Study had a full blood count measured by an automated hematology analyzer, carotid IMT by B-mode ultrasonography and brachial-ankle PWV by a non-invasive automatic waveform analyzer. Following adjustment for confounders, WBC count (β=0.07, P<0.001) and granulocyte (β=0.07, P<0.001) number were significantly positively related to PWV, but not lymphocyte number. Similarly, WBC count (β=0.08, P=0.03), lymphocyte (β=0.08, P=0.002) and granulocyte (β=0.03, P=0.04) number were significantly positively associated with carotid IMT, but only the association with lymphocyte count survived correction for other cardiovascular risk factors. In conclusion, higher WBC, particularly lymphocyte and granulocyte, count could be used, respectively, as markers of cardiovascular disease risk, measured through indicators of atherosclerosis and arterial stiffness. The associations for WBC count previously observed by others were likely driven by higher granulocytes; an index of systemic inflammation.

Childhood meat eating and inflammatory markers: the Guangzhou Biobank Cohort Study

BACKGROUND

We hypothesized that socio-economic development could, via nutritionally driven levels of pubertal sex-steroids, promote a pro-inflammatory state among men but not women in developing countries. We tested this hypothesis, using recalled childhood meat eating as a proxy for childhood nutrition, in southern China.

METHODS

We used multivariable linear regression in the Guangzhou Biobank Cohort Study phase 3 (2006-8) to examine the adjusted associations of recalled childhood meat eating, <1/week (n = 5,023), about once per week (n = 3,592) and almost daily (n = 1,252), with white blood cell count and its differentials among older (≥ 50 years) men (n = 2,498) and women (n = 7,369).

RESULTS

Adjusted for age, childhood socio-economic position, education and smoking, childhood meat eating had sex-specific associations with white blood cell count and lymphocyte count, but not granulocyte count. Men with childhood meat eating almost daily compared to <1/week had higher white blood cell count (0.33 109/L, 95% confidence interval (CI) 0.10 to 0.56) and higher lymphocyte count (0.16 109/L, 95% CI 0.07 to 0.25). Adjustment for obesity slightly attenuated these associations.

CONCLUSION

If confirmed, this hypothesis implies that economic development and the associated improvements in nutrition at puberty may be less beneficial among men than women; consistent with the widening sex differentials in life expectancy with economic development.

Parental death during childhood and adult cardiovascular risk in a developing country: the Guangzhou Biobank Cohort Study

Background

In observational studies from western countries childhood emotional adversity is usually associated with adult cardiovascular disease. These findings are open to contextual biases making evidence from other settings valuable. We examined the association of a potential marker of childhood emotional adversity with cardiovascular disease risk factors in a developing country.

Methods

We used multivariable regression in cross-sectional analysis of older (≥50 years) men (n = 7,885) and women (n = 20,886) from the Guangzhou Biobank Cohort Study (2003–8) to examine the adjusted association of early life (<18 years) parental death (none, one or two deaths) with blood pressure, fasting glucose, LDL-cholesterol, HDL-cholesterol, triglycerides, body mass index (BMI), waist-hip ratio (WHR) and white blood cell count (WBC). We used seated height and delayed 10-word recall to assess content validity of parental death as a measure of childhood emotional adversity. We also examined whether associations varied by sex.

Results

Early life parental death was associated with shorter age- and sex-adjusted seated height. It was also associated with lower 10-word recall score adjusted for age, sex, socio-economic position, leg length and lifestyle. Similarly, adjusted early life parental death was not associated with blood pressure, fasting glucose, LDL-cholesterol or HDL-cholesterol but was associated with lower BMI (−0.40, 95% confidence interval (CI) −0.62 to −0.19 for 2 compared with no early life parental deaths) and triglycerides. Associations varied by sex for WHR and WBC. Among men only, early life parental death was associated with lower WHR (−0.008, 95% CI −0.015 to −0.001) and WBC (−0.35 10⁹/L, 95% CI −0.56 to −0.13).

Conclusions

In a non-western population from a developing country, childhood emotional adversity was negatively associated with some cardiovascular risk factors, particularly among men. Our study suggests that some of the observed associations in western populations may be socially rather than biologically based or may be population specific.

Short or long sleep duration is associated with memory impairment in older Chinese: the Guangzhou Biobank Cohort Study

STUDY OBJECTIVES

To examine the association between sleep-related factors and memory impairment.

DESIGN

Cross-sectional study

SETTING

Community-based study in Guangzhou, China.

PARTICIPANTS

28,670 older Chinese (20,776 women and 7,894 men) aged 50 to 85 years.

MEASUREMENTS AND RESULTS

Demographic and socioeconomic data, sleep-related factors, and cognitive function were collected by face-to-face interview. Potential confounders, such as employment and occupational status, smoking, alcohol and tea use, physical activity, self-rated health, anthropometry, blood pressure, and fasting plasma glucose and lipids were measured. After adjusting for multiple potential confounders, an inverted U-shaped association between sleep duration and delayed word recall test (DWRT) score, a validated measure of memory impairment, was found, with 7 to 8 h of habitual sleep duration showing the highest score (P-values for trend from 3 to 7 h and from 7 to ≥ 10 h were all ≤ 0.001). Compared to sleep duration of 7 h, the adjusted odds ratio for memory impairment from the sleep duration of 3 to 4 or ≥ 10 h was 1.29 (95% confidence interval 1.07-1.56) and 1.52 (1.25-1.86), respectively. Subjects with daily napping, morning tiredness, or insomnia had significantly lower DWRT scores than those without (P ranged from < 0.001 to 0.01).

CONCLUSIONS

Short or long sleep duration was an important sleep-related factor independently associated with memory impairment and may be a useful marker for increased risk of cognitive impairment in older people.

Plasminogen activator inhibitor-1 and HbA1c defined prediabetes: the Guangzhou Biobank Cohort Study-CVD

OBJECTIVE

To examine the association between plasminogen activator inhibitor-1 (PAI-1) and diabetes status.

RESEARCH DESIGN AND METHODS

One thousand three hundred and ninety-three older Chinese were randomly selected from the Guangzhou Biobank Cohort Study. Diabetes status was classified as impaired HbA1c (IA1c) level of 5·7-6·4%, impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or diabetes using the American Diabetes Association diagnosis criteria in 2010.

RESULTS

Compared to the normoglycemic (NG) group, 421 subjects with IA1c, but without diabetes, IFG or IGT, had adverse levels of vascular risk factors, including PAI-1, lipid profile, blood pressure and anthropometry. After adjusting for multiple potential confounders, compared to the NG group, the level of plasma PAI-1 was independently and significantly increased in the IA1c and the IFG/IGT group (mean difference: 32·0 (95% confidence interval: 5·5-58·6) ng/ml and 33·3 (6·3-60·3) ng/ml, respectively; P<0·01).

CONCLUSIONS

Plasma PAI-1 level was increased in people with haemoglobin A1c (HbA1c) of 5·7-6·4% but without IFG or IGT, and in people with IFG/IGT, suggesting an increased risk for future diabetes and cardiovascular diseases in these groups.

Independent and combined associations of abdominal obesity and seated resting heart rate with type 2 diabetes among older Chinese: the Guangzhou Biobank Cohort Study

BACKGROUND

Central obesity and poor physical fitness predict the development of type 2 diabetes and cardiovascular mortality among Caucasian populations. We studied the independent and combined effect of abdominal obesity and seated resting heart rate used as an indicator of physical fitness, on the presence of type 2 diabetes among 30 519 older residents of Guangzhou, Southern China.

METHODS

Participants were stratified into four groups, based on the Asian criteria for abdominal obesity (≥90/≥ 80 cm in men/women) and the 75% cut-off point for seated resting heart rate (≥83 beats per min). The association with type 2 diabetes was assessed using multivariable logistic regression.

RESULTS

A total of 3777 (12.7%) volunteers were diagnosed with type 2 diabetes, which was independently associated with seated resting heart rate and, in particular, increasing levels of abdominal obesity (p < 0.001). An odds ratio of 3.93 (95% confidence interval = 3.48-4.43) was identified for type 2 diabetes in participants who were obese with a seated resting heart rate ≥ 83 beats per min after adjusting for potential confounders.

CONCLUSIONS

Higher seated resting heart rate, a marker of poor physical fitness, independently doubles the risk of type 2 diabetes. The strength of this association is further increased when abdominal obesity is considered.

[Study design and the preliminary results on the modes of smoking cessation in general hospitals]

To study the intervention programs on smoking cessation in a general hospital and to evaluate its effects of the programs. Four methods including: a) the intervention through specialists in the smoking cessation clinic, b) short-time intervention in the out-patient department, c) free medical intervention, d) group intervention, were adopted for different smokers, with health counseling, psychological intervention and drug treatment. Intervention effect was evaluated by standard methods. During the 20-month period of the project, we treated 690 cases and 402 completed 6-month follow-up. Preliminary results in 402 cases showed that the three methods of smoking cessation interventions could reduce the amount of cigarette smoking and increase the quitting rate. Motivation to quit smoking, intervention methods and intensity of intervention seemed the main factors. The quit rate of 6-month follow-up in the 'specialist intervention' in the smoking cessation clinic (31.6%) and in the group intervention (30.9%) was higher than short-time intervention in free medical events (15.1%). The successful rate of smoking cessation depended on the motivation of quitters, and the attitude, methods and intervention skills of the physicians. Therefore, it is necessary to explore and develop smoking cessation service models suitable to national context and individual intervention methods in China.

Passive smoking and chronic obstructive pulmonary disease: cross-sectional analysis of data from the Health Survey for England

OBJECTIVES

There is increasing evidence that passive smoking is associated with chronic respiratory diseases, but its association with chronic obstructive pulmonary disease (COPD) requires more study. In this cross-sectional analysis of data from 3 years of the Health Survey for England, the association between passive smoking exposure and risk of COPD is evaluated.

DESIGN

Cross-sectional analysis of the 1995, 1996 and 2001 Health Surveys for England including participants of white ethnicity, aged 40+ years with valid lung function data. COPD was defined using the lower limit of normal spirometric criteria for airflow obstruction. Standardised questions elicited self-reported information on demography, smoking history, ethnicity, occupation, asthma and respiratory symptoms (dyspnoea, chronic cough, chronic phlegm, wheeze). Passive smoking was measured by self-report of hours of exposure to cigarette smoke per week.

RESULTS

Increasing passive smoke exposure was independently associated with increased risk of COPD, with adjusted OR 1.05 (95% CI 0.93 to 1.18) for 1-19 h and OR 1.18 (95% CI 1.01 to 1.39) for 20 or more hours of exposure per week. Similar patterns (although attenuated and non-significant) were observed among never smokers. More marked dose-response relationships were observed between passive smoking exposure and respiratory symptoms, but the most marked effects were on the development of clinically significant COPD (airflow obstruction plus symptoms), where the risk among never smokers was doubled (OR 1.98 (95% CI 1.03 to 3.79)) if exposure exceeded 20 h/week.

CONCLUSION

This analysis adds weight to the evidence suggesting an association between passive smoking exposure and COPD.

Replication study of SNP associations for colorectal cancer in Hong Kong Chinese

BACKGROUND

Recent genome-wide association studies of colorectal cancer (CRC) have identified common single-nucleotide polymorphisms (SNPs) mapping to 10 independent loci that confer modest increased risk. These studies have been conducted in European populations and it is unclear whether these observations generalise to populations with different ethnicities and rates of CRC.

METHODS

An association study was performed on 892 CRC cases and 890 controls recruited from the Hong Kong Chinese population, genotyping 32 SNPs, which were either associated with CRC in previous studies or are in close proximity to previously reported risk SNPs.

RESULTS

Twelve of the SNPs showed evidence of an association. The strongest associations were provided by rs10795668 on 10p14, rs4779584 on 15q14 and rs12953717 on 18q21.2. There was significant linear association between CRC risk and the number of independent risk variants possessed by an individual (P=2.29 × 10(-5)).

CONCLUSION

These results indicate that some previously reported SNP associations also impact on CRC risk in the Chinese population. Possible reasons for failure of replication for some loci include inadequate study power, differences in allele frequency, linkage disequilibrium structure or effect size between populations. Our results suggest that many associations for CRC are likely to generalise across populations.

Physical activity, adiposity, and diabetes risk in middle-aged and older Chinese population: the Guangzhou Biobank Cohort Study

OBJECTIVE

Physical activity may modify the association of adiposity with type 2 diabetes. We investigated the independent and joint association of adiposity and physical activity with fasting plasma glucose, impaired fasting glucose, and type 2 diabetes in a Chinese population.

RESEARCH DESIGN AND METHODS

Middle-aged and older Chinese (n=28,946, ≥50 years, 72.4%women) from the Guangzhou Biobank Cohort Study were examined in 2003-2008. Multivariable regression was used in a cross-sectional analysis.

RESULTS

BMI, waist circumference, and waist-to-hip ratio (WHR) were positively associated with type 2 diabetes after multiple adjustment, most strongly for WHR with odds ratio (OR) of 3.99 (95% CI 3.60-4.42) for highest compared with lowest tertile. Lack of moderate-to-vigorous physical activity, but not walking, was associated with diabetes with an OR of 1.29 (1.17-1.41). The association of moderate-to-vigorous activity with fasting glucose varied with WHR tertiles (P=0.01 for interaction). Within the high WHR tertile, participants who had a lack of moderate-to-vigorous activity had an OR of 3.87 (3.22-4.65) for diabetes, whereas those who were active had an OR of 2.94 (2.41-3.59).

CONCLUSIONS

In this population, WHR was a better measure of adiposity-related diabetes risk than BMI or waist circumference. Higher moderate-to-vigorous activity was associated with lower diabetes risk, especially in abdominally obese individuals.