Rebecca Landy

Risk of preterm delivery with increasing depth of excision for cervical intraepithelial neoplasia in England: nested case-control study

Objective To determine the association between depth of excision of cervical intraepithelial neoplasia and risk of preterm birth. Design Case-control study nested in record linkage cohort study. Setting 12 hospitals in England. Participants From a cohort of 11 471 women with at least one histological sample taken at colposcopy and a live singleton birth (before or after colposcopy), 1313 women with a preterm birth (20-36 weeks) were identified and frequency matched on maternal age at delivery, parity, and study site to 1313 women with term births (38-42 weeks). Main outcome measures Risk of preterm birth and very/extreme preterm birth by depth of excisional treatment of the cervical transformation zone. Results After exclusions, 768 preterm births (cases) and 830 term births after colposcopy remained. The risk of preterm birth was no greater in women with a previous small (<10 mm) excision (absolute risk 7.5%, 95% confidence interval 6.0% to 8.9%) than in women with a diagnostic punch biopsy (7.2%, 5.9% to 8.5%). Women with a medium (10-14 mm) (absolute risk 9.6%; relative risk 1.28, 0.98 to 1.68), large (15-19 mm) (15.3%; 2.04, 1.41 to 2.96), or very large (≥20 mm) excision (18.0%; 2.40, 1.53 to 3.75) had a higher risk of preterm delivery than those with small excision. The same pattern was seen in 161 women with very/extremely preterm births (20-31 weeks) and with increasing volume excised. Most births were conceived more than three years after colposcopy, and the risk of preterm delivery did not seem to depend on time from excision to conception. Conclusions The risk of preterm birth is at most minimally affected by a small excision. Larger excisions, particularly over 15 mm or 2.66 cm3, are associated with a doubling of the risk of both preterm and very preterm births. The risk does not decrease with increasing time from excision to conception. Efforts should be made to excise the entire lesion while preserving as much healthy cervical tissue as possible. Close obstetric monitoring is warranted for women who have large excisions of the cervical transformation zone.

Are IQ and educational outcomes in teenagers related to their cannabis use? A prospective cohort study

There is much debate about the impact of adolescent cannabis use on intellectual and educational outcomes. We investigated associations between adolescent cannabis use and IQ and educational attainment in a sample of 2235 teenagers from the Avon Longitudinal Study of Parents and Children. By the age of 15, 24% reported having tried cannabis at least once. A series of nested linear regressions was employed, adjusted hierarchically by pre-exposure ability and potential confounds (e.g. cigarette and alcohol use, childhood mental-health symptoms and behavioural problems), to test the relationships between cumulative cannabis use and IQ at the age of 15 and educational performance at the age of 16. After full adjustment, those who had used cannabis ⩾50 times did not differ from never-users on either IQ or educational performance. Adjusting for group differences in cigarette smoking dramatically attenuated the associations between cannabis use and both outcomes, and further analyses demonstrated robust associations between cigarette use and educational outcomes, even with cannabis users excluded. These findings suggest that adolescent cannabis use is not associated with IQ or educational performance once adjustment is made for potential confounds, in particular adolescent cigarette use. Modest cannabis use in teenagers may have less cognitive impact than epidemiological surveys of older cohorts have previously suggested.

Impact of cervical screening on cervical cancer mortality: estimation using stage-specific results from a nested case-control study

Background:It is well established that screening can prevent cervical cancer, but the magnitude of the impact of regular screening on cervical cancer mortality is unknown.Methods:Population-based case–control study using prospectively recorded cervical screening data, England 1988–2013. Case women had cervical cancer diagnosed during April 2007–March 2013 aged 25–79 years (N=11 619). Two cancer-free controls were individually age matched to each case. We used conditional logistic regression to estimate the odds ratio (OR) of developing stage-specific cancer for women regularly screened or irregularly screened compared with women not screened in the preceding 15 years. Mortality was estimated from excess deaths within 5 years of diagnosis using stage-specific 5-year relative survival from England with adjustment for age within stage based on SEER (Surveillance, Epidemiology and End Results, USA) data.Results:In women aged 35–64 years, regular screening is associated with a 67% (95% confidence interval (CI): 62–73%) reduction in stage 1A cancer and a 95% (95% CI: 94–97%) reduction in stage 3 or worse cervical cancer: the estimated OR comparing regular (⩽5.5yearly) screening to no (or minimal) screening are 0.18 (95% CI: 0.16–0.19) for cancer incidence and 0.08 (95% CI: 0.07–0.09) for mortality. It is estimated that in England screening currently prevents 70% (95% CI: 66–73%) of cervical cancer deaths (all ages); however, if everyone attended screening regularly, 83% (95% CI: 82–84%) could be prevented.Conclusions:The association between cervical cancer screening and incidence is stronger in more advanced stage cancers, and screening is more effective at preventing death from cancer than preventing cancer itself.

Autoantibodies to Posttranslationally Modified Type II Collagen as Potential Biomarkers for Rheumatoid Arthritis

OBJECTIVE Type II collagen (CII) posttranslationally modified by reactive oxygen species (ROS-CII) that are present in the inflamed joint is an autoantigen in rheumatoid arthritis (RA). The aim of this study was to investigate the potential use of anti-ROS-CII autoantibodies as a biomarker of RA. METHODS CII was exposed to oxidants that are present in the rheumatoid joint. Autoreactivity to ROS-CII was assessed by enzyme-linked immunosorbent assays in synovial fluid (SF) and serum samples obtained from patients during various phases of RA. This group included disease-modifying antirheumatic drug (DMARD)-naive patients with early RA (n = 85 serum samples) and patients with established RA (n = 80 serum and 50 SF samples), who were categorized as either DMARD responders or DMARD nonresponders. Control subjects included anti-citrullinated protein antibody (ACPA)-positive patients with arthralgia (n = 58 serum samples), patients with osteoarthritis (OA; n = 49 serum and 52 SF samples), and healthy individuals (n = 51 serum samples). RESULTS Reactivity to ROS-CII among DMARD-naive patients with early RA was significantly higher than that among patients with ACPA-positive arthralgia, patients with OA, and healthy control subjects (P < 0.0001), with 92.9% of serum samples from the patients with early RA binding to anti-ROS-II. There was no significant difference in anti-ROS-CII reactivity between ACPA-positive and ACPA-negative patients with RA, with 93.8% and 91.6% of serum samples, respectively, binding to ROS-CII. The sensitivity and specificity of binding to ROS-CII in patients with early RA were 92% and 98%, respectively. Among patients with established RA, serum reactivity in DMARD nonresponders was significantly higher than that in DMARD responders (P < 0.01); 58.3% of serum samples from nonresponders and 7.6% of serum samples from responders bound to HOCl-ROS, while the respective values for SF were 70% and 60%. In patients with longstanding RA, autoreactivity to ROS-CII changed longitudinally. CONCLUSION Autoantibodies to ROS-CII have the potential to become diagnostic biomarkers of RA.

Characteristics and screening history of women diagnosed with cervical cancer aged 20-29 years

Background:There was concern that failure to screen women aged 20–24 years would increase the number of cancers or advanced cancers in women aged 20–29 years. We describe the characteristics of women diagnosed with cervical cancer in England aged 20–29 years and examine the association between the period of diagnosis, screening history and FIGO stage.Methods:We used data on 1800 women diagnosed with cervical cancer between April 2007 and March 2012 at age 20–29 from the National Audit of Invasive Cervical Cancers.Results:The majority of cancers (995, or 62% of those with known stage) were stage 1A. Cancer at age 20–24 years was rare (12% of those aged 20–29 years), when compared with age 25 (24%) and age 26–29 years (63%); however, cancers in women aged 20–24 years tended to be more advanced and were more often of a rare histological type. For 59% of women under age 30, the cervical cancer was screen detected, most of them (61%) as a result of their first screening test. A three-fold increase in the number of cancers diagnosed at age 25 years was seen since the start of the study period.Conclusion:Cervical cancer at age 20–24 years is rare. Most cancers in women under age 30 years are screen detected as microinvasive cancer.

HLA-dependent autoantibodies against post-translationally modified collagen type II in type 1 diabetes mellitus

Aims/hypothesisIn this study the involvement of oxidative stress in type 1 diabetes mellitus autoimmunity and the possible association with rheumatoid arthritis (RA) was investigated. We tested the hypothesis that oxidative stress induced by chronic hyperglycaemia triggers post-translational modifications and thus the formation of neo-antigens in type 1 diabetes, similar to the ones found in RA.MethodsCollagen type II (CII), a known autoantigen in RA, was treated with ribose and various reactive oxygen species (ROS). Levels of antibodies specific to native and ROS-modified CII (ROS-CII) were compared in type 1 diabetes, type 2 diabetes and healthy controls, and related to the HLA genotype.ResultsSignificantly higher binding to ROS-CII vs native CII was observed in type 1 diabetic patients possessing the HLA-DRB1*04 allele irrespective of variables of glucose control (blood glucose or HbA1c). Type 1 diabetic patients carrying a DRB1*04 allele with the shared epitope showed the highest risk for ROS-CII autoimmunity, while the DRB1*0301 allele was protective. Conversely, native CII autoimmunity was not associated with any specific DRB1 allele. Positive and inverse seroconversion rates of response to ROS-CII were high in DRB1*04-positive type 1 diabetic patients.ConclusionHyperglycaemia and oxidative stress may trigger genetically controlled autoimmunity to ROS-CII and may explain the association between type 1 diabetes mellitus and RA.

Risk of preterm birth following surgical treatment for cervical disease: executive summary of a recent symposium

We report on a symposium held in London, UK, on 16 February 2015 to discuss the association between surgical treatment of cervical intraepithelial neoplasia (CIN) and subsequent preterm birth, and to consider appropriate recommendations for the treatment of CIN and management of treated women during pregnancy. The meeting focused on CIN grades 2 and 3 that have been managed surgically. Clinical practice varies internationally: in some countries knife excision is common; in others, laser ablation is the treatment of choice; and in others, treatment predominantly involves outpatient large loop excision of the transformation zone (LLETZ), also called loop electrosurgical excision procedure (LEEP). The meeting was part of the dissemination strategy of the National Institute for Health Research (NIHR)‐funded PaCT study (preterm delivery after treatment of the cervical transformation zone). Around 50 people attended, including gynaecologic oncologists, (nurse and medical) colposcopists, obstetricians, and epidemiologists. The authors of this executive summary include the speakers at the symposium, who are also authors of important papers in the subject area, and the symposium chairs, to provide an independent opinion on the views expressed by the audience. Further details on the expertise of the authors can be found in the contribution to authorship.

Is cervical screening preventing adenocarcinoma and adenosquamous carcinoma of the cervix

While the incidence of squamous carcinoma of the cervix has declined in countries with organised screening, adenocarcinoma has become more common. Cervical screening by cytology often fails to prevent adenocarcinoma. Using prospectively recorded cervical screening data in England and Wales, we conducted a population‐based case–control study to examine whether cervical screening leads to early diagnosis and down‐staging of adenocarcinoma. Conditional logistic regression modelling was carried out to provide odds ratios (ORs) and 95% confidence intervals (CIs) on 12,418 women with cervical cancer diagnosed between ages 30 and 69 and 24,453 age‐matched controls. Of women with adenocarcinoma of the cervix, 44.3% were up to date with screening and 14.6% were non‐attenders. The overall OR comparing women up to date with screening with non‐attenders was 0.46 (95% CI: 0.39–0.55) for adenocarcinoma. The odds were significantly decreased (OR: 0.22, 95% CI: 0.15–0.33) in up to date women with Stage 2 or worse adenocarcinoma, but not for women with Stage1A adenocarcinoma 0.71 (95% CI: 0.46–1.09). The odds of Stage 1A adenocarcinoma was double among lapsed attenders (OR: 2.35, 95% CI: 1.52–3.62) compared to non‐attenders. Relative to women with no negative cytology within 7 years of diagnosis, women with Stage1A adenocarcinoma were very unlikely to be detected within 3 years of a negative cytology test (OR: 0.08, 95% CI: 0.05–0.13); however, the odds doubled 3–5 years after a negative test (OR: 2.30, 95% CI: 1.67–3.18). ORs associated with up to date screening were smaller for squamous and adenosquamous cervical carcinoma. Although cytology screening is inefficient at preventing adenocarcinomas, invasive adenocarcinomas are detected earlier than they would be in the absence of screening, substantially preventing Stage 2 and worse adenocarcinomas.

Data linkage errors in hospital administrative data when applying a pseudonymisation algorithm to paediatric intensive care records.

Objectives Our aim was to estimate the rate of data linkage error in Hospital Episode Statistics (HES) by testing the HESID pseudoanonymisation algorithm against a reference standard, in a national registry of paediatric intensive care records. Setting The Paediatric Intensive Care Audit Network (PICANet) database, covering 33 paediatric intensive care units in England, Scotland and Wales. Participants Data from infants and young people aged 0–19 years admitted between 1 January 2004 and 21 February 2014. Primary and secondary outcome measures PICANet admission records were classified as matches (records belonging to the same patient who had been readmitted) or non-matches (records belonging to different patients) after applying the HESID algorithm to PICANet records. False-match and missed-match rates were calculated by comparing results of the HESID algorithm with the reference standard PICANet ID. The effect of linkage errors on readmission rate was evaluated. Results Of 166 406 admissions, 88 596 were true matches (where the same patient had been readmitted). The HESID pseudonymisation algorithm produced few false matches (n=176/77 810; 0.2%) but a larger proportion of missed matches (n=3609/88 596; 4.1%). The true readmission rate was underestimated by 3.8% due to linkage errors. Patients who were younger, male, from Asian/Black/Other ethnic groups (vs White) were more likely to experience a false match. Missed matches were more common for younger patients, for Asian/Black/Other ethnic groups (vs White) and for patients whose records had missing data. Conclusions The deterministic algorithm used to link all episodes of hospital care for the same patient in England has a high missed match rate which underestimates the true readmission rate and will produce biased analyses. To reduce linkage error, pseudoanonymisation algorithms need to be validated against good quality reference standards. Pseudonymisation of data ‘at source’ does not itself address errors in patient identifiers and the impact these errors have on data linkage.

Is the increased risk of preterm birth following excision for cervical intraepithelial neoplasia restricted to the first birth post treatment

To explore whether the increased risk of preterm birth following treatment for cervical disease is limited to the first birth following colposcopy.