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K K Cheng

Publications and source records attributed to K K Cheng.

At least 19 recordsLinked to original sources
PubMed2018

The association between smoking cessation before and after diagnosis and non-muscle-invasive bladder cancer recurrence: a prospective cohort study.

BACKGROUND: Smoking is a major risk factor for bladder cancer, but the relationship between smoking cessation after initial treatment and bladder cancer recurrence has been investigated less frequently and not prospectively yet. METHODS: 722 non-muscle-invasive bladder cancer (NMIBC) patients (pTa, pT1, and CIS) from the prospective Bladder Cancer Prognosis Programme (BCPP) cohort, selected in the UK between 2005 and 2011, provided complete data on smoking behavior before and up to 5 years after diagnosis. The impact of smoking behavior on NMIBC recurrence was explored by multivariable Cox regression models investigating time-to-first NMIBC recurrence. RESULTS: Over a median follow-up period of 4.21 years, 403 pathologically confirmed NMIBC recurrences occurred in 210 patients. Only 25 current smokers at diagnosis quit smoking (14%) during follow-up and smoking cessation after diagnosis did not decrease risk of recurrence compared to continuing smokers (p = 0.352). CONCLUSIONS: Although quitting smoking after diagnosis might reduce the risk of recurrence based on retrospective evidence, this is not confirmed in this prospective study because the number of NMIBC patients quitting smoking before their first recurrence was too low. Nevertheless, this indicates an important role for urologists and other health care professionals in promoting smoking cessation in NMIBC.

Aged↗
PubMed2006

c-Reactive protein and the metabolic syndrome in older Chinese: Guangzhou Biobank Cohort Study.

OBJECTIVE: To examine the association between serum c-reactive protein (CRP) concentration and the metabolic syndrome (MS) using the International Diabetes Federation Metabolic Syndrome Guidelines (April, 2005) definition in an older Chinese population. METHODS: Three thousand and fourteen men and 7275 women aged 50-85 years were recruited and received a full medical check-up including measurement of blood pressure, obesity indices, fasting total, LDL-, HDL-cholesterol, triglycerides, glucose and c-reactive protein. Data describing socioeconomic and lifestyle factors was also collected. RESULTS: Vascular risk factors including waist circumference, weight gain and waist gain since the age of 18, body mass index, waist-hip-ratio, triglyceride, HDL-cholesterol, and systolic and diastolic blood pressures were positively associated with CRP in both men and women (p from <0.001 to 0.016). Compared to those without MS components, adjusted odds ratios for having elevated CRP increased in those with the MS or its components compared those without MS or components (all p<0.001), except for the low HDL-cholesterol in both genders and raised fasting glucose in men. Similarly, the risk of elevated CRP increased with escalating MS components even after adjustment of a range of potential confounders. CONCLUSIONS: There is a strong relationship between CRP and the constellation of MS components and associated vascular risk in this older Chinese population.

Aged↗
PubMed2006

Snoring and vascular risk factors and disease in a low-risk Chinese population: the Guangzhou Biobank Cohort Study.

STUDY OBJECTIVE: Snoring is a common condition, but data describing the relationship between snoring and vascular disease is very limited in Asian populations. We therefore describe the association between snoring and vascular disease and associated risk factors. DESIGN: Cross-sectional study of baseline data from the Guangzhou Biobank Cohort Study. SETTING: Community-based elderly association from Guangzhou, China. PARTICIPANTS: 10413 Chinese subjects (50-85 years of age). MEASUREMENTS: Self-reported snoring status and frequency and frequency of daytime tiredness were collected by questionnaire, as were demographic and socioeconomic data, disease histories, and potential confounders, such as smoking and alcohol consumption. Anthropometry, blood pressure, and fasting glucose and lipid profile were also measured. RESULTS: Self-reported snoring frequency was identified in 8325 (80.0%) subjects, with 51.6% reporting that they snored, of whom 15.5% were daily snorers. Increasing prevalence of snoring showed a clear positive relationship with cardiovascular risk factors, including age, obesity, blood pressure, and lipid levels (p < .001 for all). The prevalence of self-reported vascular-disease history was low but significantly associated with increasing snoring frequency. Logistic regression showed that snoring frequency was an independent predictor of vascular-disease history (odds ratios [95% confidence intervals] 1.68 [1.32-2.13] for daily snorers compared with the never-snorer reference group), of the metabolic syndrome (2.16 [1.88-2.49]) and each of its components (hypertension [1.37 (1.20-1.56)], and of dyslipidemia [1.22 (1.07-1.40)], central obesity [2.39 (2.08-2.76)], and diabetes [1.30 (1.09-1.56)]) after adjustment for potential confounders. CONCLUSION: Increasing snoring frequency was associated with an increasing prevalence of risk factors and self-reported vascular disease. Snoring may a useful marker for increased risk of vascular disease.

Aged↗
PubMed2006

Does smoking influence survival in cancer patients through effects on respiratory and vascular disease?

Patients with cancers caused by smoking may die because they continue to smoke even after diagnosis of a cancer caused by smoking. We investigated differences in cause-specific mortality between patients diagnosed with smoking-related and non-smoking-related cancers. The causes of death were classified as smoking-related cancer, non-smoking-related cancer, respiratory or vascular disease, and all other causes. We studied all 220 089 people diagnosed with cancer in Scotland between 1986 and 1996, aged between 20 and 85 years, with last follow-up on 31 December 1999. There was a moderate excess risk of dying from respiratory and vascular causes in those with smoking-related cancers, which did not fall with time since diagnosis, consistent with continued smoking by these patients. Mortality among cancer patients might fall if more assistance in stopping smoking was provided for patients who have smoking-related cancers.

Adult↗
PubMed2006

Parity and the metabolic syndrome in older Chinese women: the Guangzhou Biobank Cohort Study.

OBJECTIVE: To examine whether parity or gravidity contributes to the development of the metabolic syndrome (MS). METHODS: The first phase of the Guangzhou Biobank Cohort Study recruited 7352 women and 3065 men aged 50-93 years in 2003-4. Data on the number of live births and pregnancies, other reproduction-associated factors and socioeconomic and lifestyles factors were collected by standardized interview. The MS components were determined through physical examination and measurement of fasting blood samples. MS was identified if waist circumference was >or= 90 cm for men or >or= 80 cm for women, plus any two of: (a) raised triglyceride (TG) level (1.7 mmol/l) or specific treatment for this lipid abnormality; (b) reduced high density lipoprotein (HDL)-cholesterol (< 1.03 mmol/l in males or < 1.29 mmol/l in females) or specific treatment for this lipid abnormality; (c) raised blood pressure (BP, systolic BP >or= 130 mmHg or diastolic BP >or= 85 mmHg) or hypertension therapy; and (d) raised fasting glucose (>or= 5.6 mmol/l) or previously diagnosed type 2 diabetes. RESULTS: Before adjustment for potential confounders, we found associations between the number of births and lifestyle and socioeconomic factors in both sexes. However, in women, but not in men, body mass index (BMI), waist-hip ratio, triglyceride and glucose were positively associated with the number of birth after adjusting for a range of potential confounders. The age-adjusted prevalence of the MS increased with the number of births and pregnancies in women, but the gradient for birth was steeper than that for pregnancies [odds ratio change per birth 1.16, 95% confidence interval (CI) 1.11-1.22, P < 0.001; odds ratio change per pregnancy 1.11, 95% CI 1.06-1.16, P < 0.001], although attenuating the association adjustment did not affect the significance of these findings. There was no association in men with regard to the number of their partners' live births given the same analysis and similar shared living background with the women. CONCLUSION: Higher parity or gravidity was associated with a consistent increase in the risk of MS in Chinese women. As the association persisted after adjustment for lifestyle factors and there was no association between the risk of MS and the number of births associated with the partners of the males, the association in women may represent a biological response to pregnancy.

Abortion, Spontaneous↗
PubMed2006

A randomized controlled trial of smoking cessation for pregnant women to test the effect of a transtheoretical model-based intervention on movement in stage and interaction with baseline stage.

OBJECTIVES: To examine whether, as predicted by the transtheoretical model (TTM), stage-matched interventions will be more effective than stage-mismatched interventions. DESIGN: Randomized controlled trial of smoking cessation advice to pregnant smokers. METHODS: Pregnant women currently smoking at 12 weeks gestation were enrolled in a pragmatic three-arm trial of TTM-based interventions to help them stop smoking. One arm constituted standard midwifery advice and a self-help leaflet on stopping smoking, which is generally appropriate for women in preparation. Two arms were TTM-based. Differences in positive movement in stage towards quitting from enrolment to 30 weeks gestation and 10 days post-partum were calculated for each arm of the trial. We then examined whether, as predicted from the TTM, the relative benefit of the TTM-based intervention was greater for women in precontemplation and contemplation, for whom the control intervention was stage-mismatched, than for women in preparation, for whom the control intervention was stage-matched. RESULTS: Women in the TTM-based arms were statistically significantly more likely to move forward in stage than were women in the control arm. Contrary to the TTM-derived hypothesis, the greater relative benefit of the TTM-based intervention was seen for women in preparation stage at baseline, rather than women in precontemplation and contemplation. CONCLUSIONS: The TTM-based intervention was more effective in stage movement, but this could be due to its greater intensity. The failure to confirm that stage-matching was important casts doubt on the validity of the TTM in explaining smoking cessation behaviour in pregnancy.

Adolescent↗
PubMed2005

The influence of in-pregnancy smoking cessation programmes on partner quitting and women's social support mobilization: a randomized controlled trial [ISRCTN89131885].

BACKGROUND: Smoking cessation interventions in pregnancy could influence a woman's social behaviour and her partner's smoking behaviour, but this has not been examined in any published randomized trials. METHOD: 918 women smoking at booking for antenatal care were enrolled in a cluster-randomized trial of three interventions: standard care, self-help manual and enhanced stage-based counselling, or self-help manual, enhanced stage-based counselling and use of an interactive computer program. The outcomes were change in social support received by women between booking for maternity care and 30 weeks gestation and 10 days postpartum and reported cessation in the woman's partner at these times. RESULTS: Few pregnant women's partners stopped smoking (4.1% at 30 weeks of gestation and 5.8% at 10 days postpartum) and the probability of quitting did not differ significantly by trial arm. Women's scores on the Inventory of Socially Supportive Behaviors showed a slight decline from booking to 30 weeks gestation, and a slight increase to 10 days postpartum, but these changes did not differ significantly by trial arm. CONCLUSION: The stage-based interventions tested in this trial aimed partly to influence women's mobilization of support and might have influenced partners' quitting, but there was no evidence that they did so. Given that women and their partners often stopped smoking together, future interventions to prevent smoking in pregnant women could encourage both partners to quit together.

Adolescent↗
PubMed2005

Is inter-school variation in smoking uptake and cessation due to differences in pupil composition? A cohort study.

The aims of this study were to determine if inter-school variation in smoking prevalence was due to differences in pupil composition or other school-level factors. A cohort of 13-14-year-olds (n = 7147) from 52 schools was followed-up 1 year later. Random effects logistic regression was used to examine school variation in smoking uptake and cessation, with and without adjustment for pupil composition. Inter-school variation in smoking prevalence is not caused by differences in pupil composition but is due to differences in the onset of smoking arising because of unmeasured school contextual or collective factors operating on pupils' decisions.

Adolescent↗
PubMed2005

Is advice to stop smoking from a midwife stressful for pregnant women who smoke? Data from a randomized controlled trial.

BACKGROUND: There are no randomized trials examining whether intensive advice to pregnant smokers is more stressful than standard care. METHOD: Nine hundred eighteen U.K. women currently smoking on commencing antenatal care were randomized into three arms. Women in Arm A received one episode of brief advice to stop smoking. Women in Arm B were assessed for stage of change and worked through an exercise in self-help manuals on three occasions. Women in Arm C used a 20-min interactive computer program three times in addition to the intervention women in Arm B received. Stress was assessed by the change in score on the Perceived Stress Scale (PSS) from baseline to 30 weeks gestation, the month before delivery, and 10 days postpartum. RESULTS: There were small and not significant differences in the changes in PSS between the arms at all outcome times. There was no evidence that the importance women attached to pleasing their midwife by stopping, having failed to quit, or nulliparity modified the effect of intensive advice on change in stress levels. CONCLUSIONS.: Intensive advice to stop smoking was not associated with increases in stress. Advice and support for pregnant women to stop smoking should be given without fear of causing stress.

Delivery of Health Care↗
PubMed2005

Does stage-based smoking cessation advice in pregnancy result in long-term quitters? 18-month postpartum follow-up of a randomized controlled trial.

AIMS: To evaluate the effect on quitting smoking at 18 months postpartum of smoking cessation interventions based on the Transtheoretical Model (TTM) delivered in pregnancy compared to current standard care. It has been claimed that TTM-based interventions will continue to create quitters after the end of the intervention period. DESIGN: Cluster randomized trial. SETTING: Antenatal clinics in general practices in the West Midlands, UK. PARTICIPANTS: A total of 918 pregnant smokers originally enrolled in the trial, of which 393 women were followed-up at 18 months postpartum. INTERVENTIONS: One hundred general practices were randomized into the three trial arms. Midwives in these practices delivered three interventions: A (standard care), B (TTM-based self-help manuals) and C (TTM-based self-help manuals plus sessions with an interactive computer program giving individualized smoking cessation advice). MEASUREMENTS: Self-reported continuous and point prevalence abstinence since pregnancy. FINDINGS: When combined together, there was a slight and not significant benefit for both TTM arms compared to the control, with an odds ratio (OR) 95% confidence interval (CI) of 1.20 (0.29-4.88) for continuous abstinence. For point prevalence abstinence, the OR (95%CI) was 1.15 (0.66-2.03). Seven of the 54 (13%) women who had quit at the end of pregnancy were still quit 18 months later, and there was no evidence that the TTM-based interventions were superior in preventing relapse. CONCLUSIONS: The TTM-based interventions may have shown some evidence of a short-term benefit for quitting in pregnancy but no benefit relative to standard care when followed-up in the longer-term.

Adult↗
PubMed2005

Systemic hypertension and glaucoma: mechanisms in common and co-occurrence.

AIMS: To determine whether systemic hypertension and glaucoma might coexist more often than expected, with possible implications for treatment. METHODS: Case-control study using general practitioner database of patients with glaucoma matched with controls for age and sex. RESULTS: Hypertension was significantly more common in the 27,080 patients with glaucoma (odds ratio 1.29, 95% confidence intervals 1.23 to 1.36, p<0.001) than in controls. Treatment by oral beta blockade appeared to protect from risk (odds ratio 0.77, 95% CI 0.73 to 0.83, p<0.0001), but oral calcium channel antagonists or angiotensin converting enzyme (ACE) inhibitors did not (odds ratios 1.34, 1.24 to 1.44 and 1.16 1.09-1.24, respectively, p<0.0001 in each case). Oral corticosteroid treatment was associated with enhanced risk (odds ratio 1.78, 1.61 to 1.96). CONCLUSION: Common pathogenetic mechanisms in ciliary and renal tubular epithelia may explain coincidence of glaucoma and systemic hypertension. The choice of cardiovascular treatment, could substantially influence glaucoma incidence, with beta blockade protecting and ACE inhibitors or calcium channel blockers not affecting underlying risk.

Administration, Oral↗
PubMed2004

A methodological and substantive review of the evidence that schools cause pupils to smoke.

The objectives of this review were to examine whether smoking prevalence varies between schools independently of health promotion programmes and pupil composition, to show which school characteristics are responsible for this variation, and to examine the methodological adequacy of such studies. Searches for published studies were performed on medical, educational and social science databases, relevant articles' reference lists, and citation searches. Any study was included that described inter-school variation in smoking prevalence, or related such variation to school characteristics. A model relating pupil smoking to school, neighbourhood, and pupil characteristics unlikely and likely to be influenced by school was used to examine the adequacy of control of confounding by pupil composition. Data from studies were combined qualitatively considering methodological adequacy to examine the relation of smoking prevalence to school characteristics. Theoretical frameworks underpinning the choice of school characteristics and postulated relationships between these characteristics and smoking prevalence were described. There were large variations in smoking prevalence between ostensibly similar schools. Evidence that pupil composition did not cause this was weak, because all studies had methodological problems, including under control of relevant pupil compositional factors and over control of factors likely to represent the mechanism through which schools influence pupils' smoking. There was little evidence that elements of tobacco control policy other than bans and enforcement deterred smoking. Academic practice and school ethos were related to smoking. Academically selective schools did not influence smoking, once pupil composition was controlled. There was one study on neighbourhood influences, which were unrelated to smoking. Studies frequently offered little or no theoretical justification for associating school characteristics with smoking. Some aspects of school influence pupils' smoking, probably independently of pupil composition. However, under-control and over-control of confounding and lack of theoretical underpinning precludes definitive conclusions on how particular school characteristics influence pupils' smoking.

Adolescent↗
PubMed2004

The influence of school culture on smoking among pupils.

School factors and not solely pupil composition probably cause variation in smoking prevalence amongst schools, but there are no theoretical models to explain why. In this paper we propose a hypothesis to explain schools' influence on pupils' smoking and test this using an existing cross-sectional survey of 23,282 pupils from 166 secondary schools in the West Midlands, UK. We hypothesise that school-level educational achievement scores would not be associated with smoking prevalence, but schools providing value-added education given the social background of pupils (authoritative schools) would provide effective support and control, have a relatively strong influence on pupils' lives and be associated with lower than average smoking prevalence. Schools providing value-denuded education (laissez-faire schools) would have a relatively weak influence on pupils' lives and be associated with higher than average smoking prevalence. The school achievement measures were the proportion of pupils achieving 5A-C General Certificates of Secondary Education (5A-Cs) grades and the proportion of half days lost to truancy. Value-added/denuded terms were created by regressing 5A-Cs and truancy on five markers of the social profile of pupils at the school. Authoritative schools achieved better than expected rates on both measures. Laissez-faire schools achieved worse than expected rates on both measures. All other schools were classed as indeterminate. Multilevel logistic regression was used to relate the risk of regular smoking to school culture in both achievement and authoritative/laissez-faire terms, both with and without adjustment for pupil-level risk factors for smoking. As predicted, schools' achievement measures were unrelated to pupils' smoking. The odds ratios (95% confidence intervals) for smoking in authoritative and laissez-faire schools relative to indeterminate schools were 0.80 (0.70-0.91) and 1.16 (1.07-1.27), respectively. Adjustment for pupil-level smoking risk factors had little effect. School culture is an independent risk factor for adolescent smoking. Schools providing effective support and control might protect pupils from smoking.

Adolescent↗
PubMed2003

The risk of smoking in relation to engagement with a school-based smoking intervention.

Health promotion interventions cannot work if people do not engage with them. The aim of this study was to examine whether disengagement from an adolescent smoking prevention and cessation intervention was an independent risk factor for regular smoking 1 and 2 years later. The data were taken from a cluster randomised controlled trial, in the West Midlands, UK, based on the transtheoretical or stages of change model. In this trial, 8,352 13-14-year old school pupils enrolled, and the data in this report were based on the 7,413 and 6,782 pupils present at 1 and 2 years follow-ups, respectively. The intervention group undertook three sessions using an interactive computer programme. At the end of the programme, pupils recorded their responses to it. Pupils were classed as engaged if they thought the intervention was both useful and interesting; all others were classed as disengaged. Random effects logistic regression related the number of times engaged to regular smoking at 1 and 2 years follow-up, adjusted for school absences and 11 potential confounders. The majority of pupils were engaged by the intervention. For participants using the intervention three times but not engaging once, the odds ratios (95% confidence intervals) for smoking at 1 and 2 years relative to the controls were 1.83 (1.41-2.39) and 1.70 (1.38-2.11). For those engaging three times, they were 0.79 (0.60-1.03) and 0.96 (0.75-1.21). There was no interaction with baseline intention to smoke, classified by stage of change, but there was a borderline significant interaction with baseline smoking status, with disengagement acting as a stronger risk factor among baseline never-smokers. We conclude that disengagement from interventions is a risk factor for smoking independently of experimentation with cigarettes. The best explanation is that disengagement from school, an established risk factor for smoking, generalises to disengagement from didactic school-based health promotion programmes.

Adolescent↗
PubMed2003

A controlled trial of an expert system and self-help manual intervention based on the stages of change versus standard self-help materials in smoking cessation.

AIM: To examine the population impact and effectiveness of the Pro-Change smoking cessation course based on the Transtheoretical Model (TTM) compared to standard self-help smoking cessation literature. DESIGN: Randomized controlled trial. SETTING: Sixty-five West Midlands general practices. PARTICIPANTS: Randomly sampled patients recorded as smokers by their general practitioners received an invitation letter and 2471 current smokers agreed. INTERVENTIONS: Responders were randomized to one of four interventions. The control group received standard self-help literature. In the Manual intervention group, participants received the Pro-Change system, a self-help workbook and three questionnaires at 3-monthly intervals, which generated individually tailored feedback. In the Phone intervention group, participants received the Manual intervention plus three telephone calls. In the Nurse intervention group, participants received the Manual intervention plus three visits to the practice nurse. MEASUREMENTS: Biochemically confirmed point prevalence of being quit and 6-month sustained abstinence, 12 months after study commencement. FINDINGS: A total of 9.1% of registered current smokers participated, of whom 83.0% were not ready to quit. Less than half of participants returned questionnaires to generate second and third individualized feedback. Telephone calls reached 75% of those scheduled, but few participants visited the nurse. There were small differences between the three Pro-Change arms. The odds ratio (95% confidence intervals) for all Pro-Change arms combined versus the control arm were 1.50 (0.85-2.67) and 1.53 (0.76-3.10), for point prevalence and 6-month abstinence, respectively. This constitutes 2.1% of the TTM group versus 1.4% of the control group achieving confirmed 6-month sustained abstinence. CONCLUSIONS: There was no statistically significant benefit of the intervention apparent in this trial and the high relapse of quitters means that any population impact is small.

Adult↗