Alison Round

Clinical features of colorectal cancer before diagnosis: a population-based case–control study

Most colorectal cancers are diagnosed after the onset of symptoms. However, the risk of colorectal cancer posed by particular symptoms is largely unknown, especially in unselected populations like primary care. This was a population-based case–control study in all 21 general practices in Exeter, Devon, UK, aiming to identify and quantify the prediagnostic features of colorectal cancer. In total, 349 patients with colorectal cancer, aged 40 years or more, and 1744 controls, matched by age, sex and general practice, were studied. The full medical record for 2 years before diagnosis was coded using the International Classification of Primary Care-2. We calculated odds ratios for variables independently associated with cancer, using multivariable conditional logistic regressions, and then calculated the positive predictive values of these variables, both individually and in combination. In total, 10 features were associated with colorectal cancer before diagnosis. The positive predictive values (95% confidence interval) of these were rectal bleeding 2.4% (1.9, 3.2); weight loss 1.2% (0.91, 1.6); abdominal pain 1.1% (0.86, 1.3); diarrhoea 0.94% (0.73, 1.1); constipation 0.42% (0.34, 0.52); abnormal rectal examination 4.0% (2.4, 7.4); abdominal tenderness 1.1% (0.77, 1.5); haemoglobin <10.0 g dl−1 2.3% (1.6, 3.1); positive faecal occult bloods 7.1% (5.1, 10); blood glucose>10 mmol l−1 0.78% (0.51, 1.1): all P<0.001. Earlier diagnosis of colorectal cancer may be possible using the predictive values for single or multiple symptoms, physical signs or test results.

What are the clinical features of lung cancer before the diagnosis is made? A population based case-control study

Background: Over 38 000 new cases of lung cancer occur each year in the UK. Most are diagnosed after initial presentation to primary care, but the relative importance of the various clinical features is largely unknown. Methods: A population based case-control study was undertaken in all 21 general practices in Exeter, Devon, UK (population 128 700). 247 primary lung cancers were studied in subjects aged over 40 years diagnosed between 1998 and 2002 and 1235 controls matched by age, sex and general practice. The entire primary care record for 2 years before diagnosis was coded using the International Classification of Primary Care-2. Univariable and multivariable conditional logistic regression analyses were used to identify and quantify clinical features independently associated with lung cancer. The main outcome measures were odds ratios and positive predictive values for these variables. Results: Seven symptoms (haemoptysis, loss of weight, loss of appetite, dyspnoea, thoracic pain, fatigue and cough), one physical sign (finger clubbing), and two abnormal investigation results (thrombocytosis and abnormal spirometry) were associated with lung cancer in multivariable analyses, as was cigarette smoking. After excluding variables reported in the final 180 days before diagnosis, haemoptysis, dyspnoea and abnormal spirometry remained independently associated with cancer. Conclusions: This study provides an evidence base for selection of patients for investigation of possible lung cancer, both for clinicians and for developers of guidelines.

Effect on hospital attendance rates of giving patients a copy of their referral letter: randomised controlled trial

Abstract Objectives: To investigate whether sending patients a copy of their referral letter can reduce non-attendance at outpatient departments. Design: Blinded randomised controlled trial. Setting: 13 general practices in Exeter, Devon. Subjects: 2078 new consultant referrals from 26 doctors. Main outcome measures: Non-attendance at outpatient departments. Results: The doctors excluded 117 (5.6%) referrals, and 100 (4.8%) received no appointment. Attendance data were available for 1857 of the 1861 patients sent an appointment (99.8%). The receipt of a copy letter had no effect on the non-attendance rate: copy 50/912 (5.5%) versus control 50/945 (5.3%). Conclusion: Copy letters are ineffective in reducing non-attendance at outpatient departments.

Raised inflammatory markers

What is the evidence for using C reactive protein, erythrocyte sedimentation rate, and plasma viscosity in diagnosis?

Screening for hepatitis C in genito-urinary medicine clinics: a cost utility analysis

BACKGROUND/AIMS To estimate the cost utility (cost per QALY) of screening for hepatitis C (HCV) infection in people attending genito-urinary medicine clinics in England. METHODS An epidemiological model of screening and diagnosis was combined with a Markov chain model of treatment with combination therapy to estimate cost utility. Parameters for the model were informed by literature review, expert opinion and a survey of current screening practice. RESULTS The base case estimate was about pound 85,000 per QALY. Selective screening is more cost effective. If screening is restricted to only 20% or 10% of attenders, cost utility is estimated as pound 39,647 and pound 34,288 per QALY. If screening is restricted only to those with a history of injecting drug use, cost utility would be pound 27,138 per QALY. Estimates are particularly sensitive to acceptance rates for screening and treatment. CONCLUSIONS Universal screening for HCV in GUM clinics is unlikely to be cost effective. There is limited evidence to support screening of people other than those with a history of injecting drug use and even this policy should be considered with some care and in the context of further research.

Offspring birthweight is not associated with paternal insulin resistance

Aims/hypothesisLow birthweight is associated with insulin resistance and other insulin resistance-related phenotypes: diabetes, hypertension, and vascular disease in later life. The underlying mechanism is unclear. The foetal insulin hypothesis proposes that a single genetic predisposition to beta cell dysfunction/insulin resistance results in both reduced insulin-dependent foetal growth in utero, hence low birthweight, and predisposition to type 2 diabetes. The aim of this study was to test whether, as predicted by the foetal insulin hypothesis, there is an association between measures of paternal insulin resistance and offspring birthweight.Subjects and MethodsThe Exeter Family Study of Childhood Health (EFSOCH) is a community-based study within central Exeter (UK), established to test the foetal insulin hypothesis prospectively. Associations were tested between offspring birthweight and paternal insulin resistance, calculated by homeostasis model assessment analysis in 986 families using data relating to singleton, non-diabetic, UK white pregnancies. Ethics approval was given by the North and East Devon local ethics committee.ResultsOffspring birthweight was not significantly correlated with log paternal insulin resistance (r=0, p=0.91), log HDL cholesterol concentration (r=−0.02, p=0.47) or log triglyceride concentration (r=0, p=0.99) when corrected for paternal BMI and common confounders. Multiple linear regression analysis confirmed that paternal insulin resistance was not an independent predictor of offspring birthweight.Conclusions/interpretationResults from a young, adult, non-diabetic population do not support the foetal insulin hypothesis as an explanation for the association of low birthweight with insulin resistance.

Investigating fatigue in primary care.

Tiredness is a common presentation in general practice, but how useful are investigations, and what tests should be done and how soon?

Not a silent killer

When will ovarian cancer stop being called the silent killer?1 If it were truly silent, general practitioners could hardly be blamed for missing it. It is far from silent: its noise is difficult to interpret. Recent studies of newly diagnosed women show that symptoms are common and reported to general practitioners.2 3 Although the …

Wegener's granulomatosis simulated by a T cell lymphoma of the lung

A case of primary T cell lymphoma of the lung associated with antineutrophil cytoplasmic antibody simulated Wegeners granulomatosis, the patient having features compatible with but not diagnostic of Wegeners granulomatosis.