A step-wise approach to developing indicators to compare the performance of maternity units using hospital administrative data.

Hospital administrative data are attractive for comparing performance of maternity units because of their often large sample sizes, lack of selection bias and the relatively low costs of accessing these data compared with conducting primary data collection. However, using administrative data to develop indicators can also present challenges including varying data quality, the limited detail on clinical risk factors and a lack of structural and user experience measures. This review illustrates how to develop performance indicators for maternity units using hospital administrative data, including methods to address the challenges that administrative data pose. TWEETABLE ABSTRACT: How to develop maternity indicators from administrative data.

Association between age and access to immediate breast reconstruction in women undergoing mastectomy for breast cancer.

BACKGROUND: National guidelines state that patients with breast cancer undergoing mastectomy in England should be offered immediate breast reconstruction (IR), unless precluded by their fitness for surgery or the need for adjuvant therapies. METHODS: A national study investigated factors that influenced clinicians' decision to offer IR, and collected data on case mix, operative procedures and reconstructive decision-making among women with breast cancer having a mastectomy with or without IR in the English National Health Service between 1 January 2008 and 31 March 2009. Multivariable logistic regression was used to examine the relationship between whether or not women were offered IR and their characteristics (tumour burden, functional status, planned radiotherapy, planned chemotherapy, perioperative fitness, obesity, smoking status and age). RESULTS: Of 13 225 women, 6458 (48·8 per cent) were offered IR. Among factors the guidelines highlighted as relevant to decision-making, the three most strongly associated with the likelihood of an offer were tumour burden, planned radiotherapy and performance status. Depending on the combination of their values, the probability of an IR offer ranged from 7·4 to 85·1 per cent. A regression model that included all available factors discriminated well between whether or not women were offered IR (c-statistic 0·773), but revealed that increasing age was associated with a fall in the probability of an IR offer beyond that expected from older patients' tumour and co-morbidity characteristics. CONCLUSION: Clinicians are broadly following guidance on the offer of IR, except with respect to patients' age.

Determinants of stoma reversal in rectal cancer patients who had an anterior resection between 2009 and 2012 in the English National Health Service.

AIM: The rate of ileostomy reversal was estimated in patients undergoing an elective anterior resection for rectal cancer and factors associated with reversal were identified. METHOD: The records of 4879 rectal patients who had an ileostomy created during anterior resection between 2009 and 2012 were identified in the National Bowel Cancer Audit database and linked to administrative records of the Hospital Episode Statistics. Patients were followed from surgery. Multivariable proportional hazards regression was used to estimate the impact of patient and cancer characteristics on ileostomy reversal with death as the competing risk. RESULTS: Within 18 months from anterior resection, 3536 (72.5%) patients had undergone ileostomy reversal. The reversal rate was lower in the following circumstances: older patients [hazard ratio (HR) 0.90; 95% CI 0.84-0.96, aged 80 vs 70 years], male gender (HR 0.90; 0.84-0.97), higher American Society of Anesthesiologists (ASA) grade (HR 0.64; 0.56-0.74, ASA 3+ vs 1), more advanced cancer (HR 0.77; 0.69-0.87, T3 vs T1), socioeconomic deprivation (HR 0.83; 0.74-0.93, most vs least deprived quintile), comorbidity (HR 0.92; 0.84-1.00, one vs no comorbidity) and open surgical procedure (HR 0.90; 0.84-0.97, open vs laparoscopic). CONCLUSION: Overall, two-thirds of ileostomies were reversed within 18 months. Reversal rates were linked to patient and cancer characteristics (age, sex, fitness and stage), mode of surgical access and socioeconomic deprivation. Observed lower reversal rates in patients from poorer backgrounds may indicate inequity in access.

Lifetime cost effectiveness of different brands of prosthesis used for total hip arthroplasty: a study using the NJR dataset.

There is little evidence on the cost effectiveness of different brands of hip prostheses. We compared lifetime cost effectiveness of frequently used brands within types of prosthesis including cemented (Exeter V40 Contemporary, Exeter V40 Duration and Exeter V40 Elite Plus Ogee), cementless (Corail Pinnacle, Accolade Trident, and Taperloc Exceed) and hybrid (Exeter V40 Trilogy, Exeter V40 Trident, and CPT Trilogy). We used data from three linked English national databases to estimate the lifetime risk of revision, quality-adjusted life years (QALYs) and cost. For women with osteoarthritis aged 70 years, the Exeter V40 Elite Plus Ogee had the lowest risk of revision (5.9% revision risk, 9.0 QALYs) and the CPT Trilogy had the highest QALYs (10.9% revision risk, 9.3 QALYs). Compared with the Corail Pinnacle (9.3% revision risk, 9.22 QALYs), the most commonly used brand, and assuming a willingness-to-pay of £20,000 per QALY gain, the CPT Trilogy is most cost effective, with an incremental net monetary benefit of £876. Differences in cost effectiveness between the hybrid CPT Trilogy and Exeter V40 Trident and the cementless Corail Pinnacle and Taperloc Exceed were small, and a cautious interpretation is required, given the limitations of the available information. However, it is unlikely that cemented brands are among the most cost effective. Similar patterns of results were observed for men and other ages. The gain in quality of life after total hip arthroplasty, rather than the risk of revision, was the main driver of cost effectiveness. Cite this article: Bone Joint J 2015;97-B:762-70.

Socioeconomic deprivation and inpatient complication rates following mastectomy and breast reconstruction surgery.

BACKGROUND: Socioeconomic deprivation is known to influence the presentation of patients with breast cancer and their subsequent treatments, but its relationship with surgical outcomes has not been investigated. A national prospective cohort study was undertaken to examine the effect of deprivation on the outcomes of mastectomy with or without immediate breast reconstruction. METHODS: Data were collected on patient case mix, operative procedures and inpatient complications following mastectomy with or without immediate breast reconstruction in the English National Health Service between 1 January 2008 and 31 March 2009. Multivariable logistic regression was used to examine the relationship between patients' level of (regional) deprivation and the likelihood of local (mastectomy site, flap, flap donor and implant) and distant or systemic complications, after adjusting for potential confounding factors. RESULTS: Of 13,689 patients who had a mastectomy, 2849 (20.8 per cent) underwent immediate reconstruction. In total, 1819 women (13.3 per cent) experienced inpatient complications. The proportion with complications increased from 11.2 per cent among the least deprived quintile (Q1) to 16.1 per cent in the most deprived (Q5). Complication rates were higher among smokers, the obese and those with poorer performance status, but were not affected by age, tumour type or Nottingham Prognostic Index. Adjustment for patient-related factors only marginally reduced the association between deprivation and complication incidence, to 11.4 per cent in Q1 and 15.4 per cent in Q5. Further adjustment for length of hospital stay, hospital case volume and immediate reconstruction rate had minimal effect. CONCLUSION: Rates of postoperative complications after mastectomy and breast reconstruction surgery were higher among women from more deprived backgrounds.

Model for risk adjustment of postoperative mortality in patients with colorectal cancer.

BACKGROUND: A model was developed for risk adjustment of postoperative mortality in patients with colorectal cancer in order to make fair comparisons between healthcare providers. Previous models were derived in relatively small studies with the use of suboptimal modelling techniques. METHODS: Data from adults included in a national study of major surgery for colorectal cancer were used to develop and validate a logistic regression model for 90-day mortality. The main risk factors were identified from a review of the literature. The association with age was modelled as a curved continuous relationship. Bootstrap resampling was used to select interactions between risk factors. RESULTS: A model based on data from 62 314 adults was developed that was well calibrated (absolute differences between observed and predicted mortality always smaller than 0·75 per cent in deciles of predicted risk). It discriminated well between low- and high-risk patients (C-index 0·800, 95 per cent c.i. 0·793 to 0·807). An interaction between age and metastatic disease was included as metastatic disease was found to increase postoperative risk in young patients aged 50 years (odds ratio 3·53, 95 per cent c.i. 2·66 to 4·67) far more than in elderly patients aged 80 years (odds ratio 1·48, 1·32 to 1·66). CONCLUSION: Use of this model, estimated in the largest number of patients with colorectal cancer to date, is recommended when comparing postoperative mortality of major colorectal cancer surgery between hospitals, clinical teams or individual surgeons.

Impact of third- and fourth-degree perineal tears at first birth on subsequent pregnancy outcomes: a cohort study.

OBJECTIVE: To investigate, among women who have had a third- or fourth-degree perineal tear, the mode of delivery in subsequent pregnancies as well as the recurrence rate of third- or fourth-degree tears. DESIGN: A retrospective cohort study of deliveries using a national administrative database. SETTING: The English National Health Service between 1 April 2004 and 31 March 2012. POPULATION: A total of 639,402 primiparous women who had a singleton, term, vaginal live birth between April 2004 and March 2011, and a second birth before April 2012. METHODS: Multivariable logistic regression models were used to estimate odds ratios, adjusted for other risk factors. MAIN OUTCOME MEASURES: Mode of delivery and recurrence of tears at second birth. RESULTS: The rate of elective caesarean at second birth was 24.2% for women with a third- or fourth-degree tear at first birth, and 1.5% for women without (adjusted odds ratio, aOR 18.3, 95% confidence interval, 95% CI 16.4-20.4). Among women who had a vaginal delivery at second birth, the rate of third- or fourth-degree tears was 7.2% for women with a third- or fourth-degree tear at first birth, compared with 1.3% for women without (aOR 5.5, 95% CI 5.2-5.9). CONCLUSIONS: The risk of a severe perineal tear is increased five-fold in women who had a third- or fourth-degree tear in their first delivery. This increased risk should be taken into account when decisions about mode of delivery are made.

Dysferlin regulates cell membrane repair by facilitating injury-triggered acid sphingomyelinase secretion.

Dysferlin deficiency compromises the repair of injured muscle, but the underlying cellular mechanism remains elusive. To study this phenomenon, we have developed mouse and human myoblast models for dysferlinopathy. These dysferlinopathic myoblasts undergo normal differentiation but have a deficit in their ability to repair focal injury to their cell membrane. Imaging cells undergoing repair showed that dysferlin-deficit decreased the number of lysosomes present at the cell membrane, resulting in a delay and reduction in injury-triggered lysosomal exocytosis. We find repair of injured cells does not involve formation of intracellular membrane patch through lysosome-lysosome fusion; instead, individual lysosomes fuse with the injured cell membrane, releasing acid sphingomyelinase (ASM). ASM secretion was reduced in injured dysferlinopathic cells, and acute treatment with sphingomyelinase restored the repair ability of dysferlinopathic myoblasts and myofibers. Our results provide the mechanism for dysferlin-mediated repair of skeletal muscle sarcolemma and identify ASM as a potential therapy for dysferlinopathy.

A population-based cohort study of the effect of Caesarean section on subsequent fertility.

STUDY QUESTION: Is there an association between Caesarean section and subsequent fertility? SUMMARY ANSWER: There is no or only a slight effect of Caesarean section on future fertility. WHAT IS KNOWN ALREADY: Previous studies have reported that delivery by a Caesarean section is associated with fewer subsequent pregnancies and longer inter-pregnancy intervals. The interpretation of these findings is difficult because of significant weaknesses in study designs and analytical methods, notably the potential effect of the indication for Caesarean section on subsequent delivery. STUDY DESIGN, SIZE, DURATION: Retrospective cohort study of 1 047 644 first births to low-risk women using routinely collected, national administrative data of deliveries in English maternity units between 1 April 2000 and 31 March 2012. PARTICIPANTS/MATERIALS, SETTING, METHODS: Primiparous women aged 15-40 years who had a singleton, term, live birth in the English National Health Service were included. Women with high-risk pregnancies involving placenta praevia, pre-eclampsia, eclampsia (gestational or pre-existing), hypertension or diabetes were excluded from the main analysis. Kaplan-Meier analyses and Cox proportional hazard models were used to assess the effect of mode of delivery on time to subsequent birth, adjusted for age, ethnicity, socio-economic deprivation and year of index delivery. MAIN RESULTS AND THE ROLE OF CHANCE: Among low-risk primiparous women, 224 024 (21.4%) were delivered by Caesarean section. The Kaplan-Meier estimate of the subsequent birth rate at 10 years for the cohort was 74.7%. Compared with vaginal delivery, subsequent birth rates were marginally lower after elective Caesarean for breech (adjusted hazard ratio, HR 0.96, 95% CI 0.94-0.98). Larger effects were observed after elective Caesarean for other indications (adjusted HR 0.81, 95% CI 0.78-0.83), and emergency Caesarean (adjusted HR 0.91, 95% CI 0.90-0.93). The effect was smallest for elective Caesarean for breech, and this was not statistically significant in women younger than 30 years of age (adjusted HR 0.98, 95% CI 0.96-1.01). LIMITATIONS, REASONS FOR CAUTION: We used birth cohorts from maternity units with good quality parity information. The data are likely to be nationally representative because the characteristics of the deliveries in included and omitted units were similar. There may be residual bias in our adjusted results due to unmeasured maternal factors such as obesity and voluntary absence of conception. Any residual bias would lead to an overestimate of the effect of Caesarean section on fertility, and the true effect is therefore likely to be smaller than the effect reported in our study. WIDER IMPLICATIONS OF THE FINDINGS: Our results provide strong evidence that there is no or only a slight effect of Caesarean section on future fertility. The clinical and social circumstances leading to the Caesarean section have a greater effect on future fertility than the Caesarean section itself. This finding is important in light of rising Caesarean section rates. STUDY FUNDING/COMPETING INTEREST(S): IG-U is supported by the Lindsay Stewart R&D Centre, Royal College of Obstetricians and Gynaecologists, UK. The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: n/a.

Vaginal birth after caesarean section: a cohort study investigating factors associated with its uptake and success.

OBJECTIVES: To investigate the demographic and obstetric factors associated with the uptake and success rate of vaginal birth after caesarean section (VBAC). DESIGN: Cohort study using data from Hospital Episode Statistics. SETTING: English National Health Service. POPULATION: Women whose first birth resulted in a live singleton delivery by caesarean section between 1 April 2004 and 31 March 2011, and who had a second birth before 31 March 2012. METHODS: Logistic regression to estimate adjusted odds ratios (OR). MAIN OUTCOME MEASURES: Attempted and successful VBAC. RESULTS: Among the 143,970 women in the cohort, 75,086 (52.2%) attempted a VBAC for their second birth. Younger women, those of non-white ethnicity and those living in a more deprived area had higher rates of attempted VBAC. Overall, 47,602 women (63.4%) who attempted a VBAC had a successful vaginal birth. Younger women and women of white ethnicity had higher success rates. Black women had a particularly low success rate (OR, 0.54; 95% confidence interval [CI], 0.50-0.57). Women who had an emergency caesarean section in their first birth also had a lower VBAC success rate, particularly those with a history of failed induction of labour (OR, 0.59; 95% CI, 0.53-0.67). CONCLUSION: In this national cohort, just over one-half of women with a primary caesarean section who were eligible for a trial of labour attempted a VBAC for their second birth. Of these, almost two-thirds successfully achieved a vaginal delivery.

Third- and fourth-degree perineal tears among primiparous women in England between 2000 and 2012: time trends and risk factors.

OBJECTIVE: To describe the trends of severe perineal tears in England and to investigate to what extent the changes in related risk factors could explain the observed trends. DESIGN: A retrospective cohort study of singleton deliveries from a national administrative database. SETTING: The English National Health Service between 1 April 2000 and 31 March 2012. POPULATION: A cohort of 1 035 253 primiparous women who had a singleton, term, cephalic, vaginal birth. METHODS: Multivariable logistic regression was used to estimate the impact of financial year of birth (labelled by starting year), adjusting for major risk factors. MAIN OUTCOME MEASURE: The rate of third-degree (anal sphincter is torn) or fourth-degree (anal sphincter as well as rectal mucosa are torn) perineal tears. RESULTS: The rate of reported third- or fourth-degree perineal tears tripled from 1.8 to 5.9% during the study period. The rate of episiotomy varied between 30 and 36%. An increasing proportion of ventouse deliveries (from 67.8 to 78.6%) and non-instrumental deliveries (from 15.1 to 19.1%) were assisted by an episiotomy. A higher risk of third- or fourth-degree perineal tears was associated with a maternal age above 25 years, instrumental delivery (forceps and ventouse), especially without episiotomy, Asian ethnicity, a more affluent socio-economic status, higher birthweight, and shoulder dystocia. CONCLUSIONS: Changes in major risk factors are unlikely explanations for the observed increase in the rate of third- or fourth-degree tears. The improved recognition of tears following the implementation of a standardised classification of perineal tears is the most likely explanation.

Rates of subsequent surgery following endometrial ablation among English women with menorrhagia: population-based cohort study.

OBJECTIVE: To assess the risk of further surgery amongst women who had an initial endometrial ablation (EA) for the treatment of heavy menstrual bleeding (HMB). DESIGN: A retrospective cohort study using a national administrative database. SETTING: Population-based study of hospital care in the English National Health Service. POPULATION: A cohort of 114,910 women who had EA for HMB between January 2000 and December 2011. METHODS: Multiple Cox regressions were performed to identify the risks of a further procedure, adjusted for age, social deprivation, year and type of initial EA, and presence of fibroids/polyps. MAIN OUTCOME MEASURES: Time to repeat EA or hysterectomy after initial surgery. RESULTS: Of 114,910 women undergoing EA, 16.7% had at least one subsequent procedure within 5 years. Higher rates of subsequent surgery were associated with younger age at initial EA, with women aged under 35 years having an adjusted hazard ratio of 2.83 (95% CI 2.67-2.99), compared with women aged over 45 years. Women who had radiofrequency ablation were less likely to have subsequent surgery as compared with first-generation techniques (HR 0.69, 95% CI 0.63-0.76). The rate of a subsequent hysterectomy within 5 years was 13.5%. Younger women (OR 0.59, 95% CI 0.51-0.69) and those who had balloon, microwave, or radiofrequency ablation were less likely to have a second EA procedure, rather than a hysterectomy. CONCLUSIONS: One in six women have further surgery after EA for HMB, which is a higher rate than reported in clinical trials. This risk of further surgery decreases with age.

Impact of Caesarean section on subsequent fertility: a systematic review and meta-analysis.

STUDY QUESTION: Is there an association between a Caesarean section and subsequent fertility? SUMMARY ANSWER: Most studies report that fertility is reduced after Caesarean section compared with vaginal delivery. However, studies with a more robust design show smaller effects and it is uncertain whether the association is causal. WHAT IS KNOWN ALREADY: A previous systematic review published in 1996 summarizing six studies including 85 728 women suggested that Caesarean section reduces subsequent fertility. The included studies suffer from severe methodological limitations. STUDY DESIGN, SIZE, DURATION: Systematic review and meta-analysis of cohort studies comparing subsequent reproductive outcomes of women who had a Caesarean section with those who delivered vaginally. PARTICIPANTS/MATERIALS, SETTING, METHODS: Searches of Cochrane Library, Medline, Embase, CINAHL Plus and Maternity and Infant Care databases were conducted in December 2011 to identify randomized and non-randomized studies that compared the subsequent fertility outcomes after a Caesarean section and after a vaginal delivery. Eighteen cohort studies including 591 850 women matched the inclusion criteria. Risk of bias was assessed by the Newcastle-Ottawa scale (NOS). Data extraction was done independently by two reviewers. The meta-analysis was based on a random-effects model. Subgroup analyses were performed to assess whether the estimated effect was influenced by parity, risk adjustment, maternal choice, cohort period, and study quality and size. MAIN RESULTS AND THE ROLE OF CHANCE: The impact of Caesarean section on subsequent pregnancies could be analysed in 10 studies and on subsequent births in 16 studies. A meta-analysis suggests that patients who had undergone a Caesarean section had a 9% lower subsequent pregnancy rate [risk ratio (RR) 0.91, 95% confidence interval (CI) (0.87, 0.95)] and 11% lower birth rate [RR 0.89, 95% CI (0.87, 0.92)], compared with patients who had delivered vaginally. Studies that controlled for maternal age or specifically analysed primary elective Caesarean section for breech delivery, and those that were least prone to bias according to the NOS reported smaller effects. LIMITATIONS, REASONS FOR CAUTION: There is significant variation in the design and methods of included studies. Residual bias in the adjusted results is likely as no study was able to control for a number of important maternal characteristics, such as a history of infertility or maternal obesity. WIDER IMPLICATIONS OF THE FINDINGS: Further research is needed to reduce the impact of selection bias by indication through creating more comparable patient groups and applying risk adjustment.

Socioeconomic differences in patient-reported outcomes after a hip or knee replacement in the English National Health Service.

BACKGROUND: We investigated socioeconomic differences in patient-reported outcomes after a hip or knee replacement and the contribution of health differences beforehand. METHODS: Our sample included 121 983 patients in England who had an operation in 2009-2011. Socioeconomic status was measured with quintiles of the ranking of areas by the English Index of Multiple Deprivation. Outcomes at 6 months were the Oxford hip or knee score (OHS or OKS) that measure pain and disability on a scale from 0 (worst) to 48 (best), and the percentage reporting no improvement in problems. Adjustment was made for age, sex, ethnicity, comorbidity, general health, revision surgery, primary diagnosis, preoperative OHS or OKS and having longstanding problems. RESULTS: Comparing the most- with the least-deprived group, the mean OHS was 5.0 points lower and the OKS 5.4 lower. Adjusted differences, reflecting the differences in improvement in the condition, were 2.8 [95% confidence interval (CI): 2.5-3.0] on OHS and 2.4 (95% CI: 2.2-2.7) on OKS. Adjusted odds ratios for reporting no improvement were 1.4 (1.2-1.6) for the hip and 1.4 (1.3-1.5) for the knee. CONCLUSIONS: On average, patients living in socioeconomically deprived areas had worse outcomes after surgery, partly related to preoperative differences in health and disease severity and partly to less postoperative improvement.

Reoperation rates after breast conserving surgery for breast cancer among women in England: retrospective study of hospital episode statistics.

OBJECTIVES: To examine whether rate of reoperation after breast conserving surgery is associated with patients' characteristics and investigate whether reoperation rates vary among English NHS trusts. DESIGN: Cohort study using patient level data from hospital episode statistics. SETTING: English NHS trusts. PARTICIPANTS: Adult women who had breast conserving surgery between 1 April 2005 and 31 March 2008. MAIN OUTCOME MEASURE: Reoperation rates after primary breast conserving surgery within 3 months, adjusted using logistic regression for tumour type, age, comorbidity, and socioeconomic deprivation. Tumours were grouped by whether a carcinoma in situ component was coded at the time of the primary breast conserving surgery. RESULTS: 55,297 women had primary breast conserving surgery in 156 NHS trusts during the three year period. 11,032 (20.0%, 95% confidence interval 19.6% to 20.3%) women had at least one reoperation. 10,212 (18.5%, 18.2% to 18.8%) had one reoperation only; of these, 5943 (10.7%, 10.5% to 11.0%) had another breast conserving procedure and 4269 (7.7%, 7.5% to 7.9%) had a mastectomy. Of the 45,793 women with isolated invasive disease, 8229 (18.0%) had at least one reoperation. In comparison, 2803 (29.5%) of the 9504 women with carcinoma in situ had at least one reoperation (adjusted odds ratio 1.9, 95% confidence interval 1.8 to 2.0). Substantial differences were found in the adjusted reoperation rates among the NHS trusts (10th and 90th centiles 12.2% and 30.2%). CONCLUSION: One in five women who had breast conserving surgery in England had a reoperation. Reoperation was nearly twice as likely when the tumour had a carcinoma in situ component coded. Women should be informed of this reoperation risk when deciding on the type of surgical treatment of their breast cancer.

The effect of aspirin and low-molecular-weight heparin on venous thromboembolism after knee replacement: a non-randomised comparison using National Joint Registry Data.

We compared thromboembolic events, major haemorrhage and death after knee replacement in patients receiving either aspirin or low-molecular-weight heparin (LMWH). Data from the National Joint Registry for England and Wales were linked to an administrative database of hospital admissions in the English National Health Service. A total of 156,798 patients between April 2003 and September 2008 were included and followed for 90 days. Multivariable risk modelling was used to estimate odds ratios adjusted for baseline risk factors (AOR). An AOR < 1 indicates that risk rates are lower with LMWH than with aspirin. In all, 36,159 patients (23.1%) were prescribed aspirin and 120,639 patients (76.9%) were prescribed LMWH. We found no statistically significant differences between the aspirin and LMWH groups in the rate of pulmonary embolism (0.49% vs 0.45%, AOR 0.88 (95% confidence interval (CI) 0.74 to 1.05); p = 0.16), 90-day mortality (0.39% vs 0.45%, AOR 1.13 (95% CI 0.94 to 1.37); p = 0.19) or major haemorrhage (0.37% vs 0.39%, AOR 1.01 (95% CI 0.83 to 1.22); p = 0.94). There was a significantly greater likelihood of needing to return to theatre in the aspirin group (0.26% vs 0.19%, AOR 0.73 (95% CI 0.58 to 0.94); p = 0.01). Between patients receiving LMWH or aspirin there was only a small difference in the risk of pulmonary embolism, 90-day mortality and major haemorrhage. These results should be considered when the existing guidelines for thromboprophylaxis after knee replacement are reviewed.

Sociodemographic differences in the severity and duration of disease amongst patients undergoing hip or knee replacement surgery.

BACKGROUND: Differences in the use of hip and knee replacement by sex, age, ethnicity or socioeconomic status may lead to differences in disease severity between those who have surgery. METHODS: Analyses used data collected from 117,736 patients in 2009-10 via the Patient Reported Outcome Measures (PROMs) programme in England. Adjusted differences were estimated in the Oxford Hip Score (OHS) or the Oxford Knee Score (OKS), both expressed on a scale from 0 to 48, and the proportion with longstanding problems (>5 years), expressed as odds ratios (ORs). RESULTS: Women had more severe pain and disability than men on average (difference OHS 2.3 and OKS 3.3), but less often longstanding problems. Compared with white patients, average severity was higher in South Asian patients (difference OHS 2.7 and OKS 3.0) and in black patients (difference OHS 0.9 and OKS 1.6), who also more often had longstanding problems (OR 1.40 for hip and 1.54 for knee). Patients from deprived areas had more severe disease (difference OHS 3.6 and OKS 3.3 between least and most deprived quintile). CONCLUSIONS: There is evidence that non-white and deprived patients tend to have hip and knee replacement surgery at a later stage in the course of their disease.

The effect of aspirin and low-molecular-weight heparin on venous thromboembolism after hip replacement: a non-randomised comparison from information in the National Joint Registry.

We compared thromboembolic events, major haemorrhage and death after total hip replacement in patients receiving either aspirin or low-molecular-weight heparin (LMWH). We analysed data from the National Joint Registry for England and Wales linked to an administrative database of hospital admissions in the English National Health Service. A total of 108,584 patients operated on between April 2003 and September 2008 were included and followed up for 90 days. Multivariable risk modelling and propensity score matching were used to estimate odds ratios (OR) adjusted for baseline risk factors. An OR < 1 indicates that rates are lower with LMWH than with aspirin. In all, 21.1% of patients were prescribed aspirin and 78.9% LMWH. Without adjustment, we found no statistically significant differences. The rate of pulmonary embolism was 0.68% in both groups and 90-day mortality was 0.65% with aspirin and 0.61% with LMWH (OR 0.93; 95% CI 0.77 to 1.11). With risk adjustment, the difference in mortality increased (OR 0.84; 95% CI 0.69 to 1.01). With propensity score matching the mortality difference increased even further to 0.65% with aspirin and 0.51% with LMWH (OR 0.77; 95% CI 0.61 to 0.98). These results should be considered when the conflicting recommendations of existing guidelines for thromboprophylaxis after hip replacement are being addressed.

Regional variation in use of immediate breast reconstruction after mastectomy for breast cancer in England.

AIMS: English national guidelines recommend that breast reconstruction is made available to women with breast cancer undergoing mastectomy. We examined the use of immediate reconstruction (IR) across English Cancer Networks, who are responsible for the regional organisation of cancer services and ensuring equitable access to treatment. METHODS: We analysed Hospital Episodes Statistics data for all women with breast cancer who underwent mastectomy in the English NHS between April 2006 and February 2009. IR rates were calculated for the 30 Networks. Multivariable logistic regression was used to adjust the rates for patient age, comorbidity, ethnicity and socioeconomic deprivation. RESULTS: Of 44 837 mastectomy patients, 7375 (16.5%) underwent IR. The IR rate was highest in women under 50 years (32.7%) and lowest in women aged 70 years or over (1.5%), and was lower in women with more comorbidities. Unadjusted IR rates varied from 8.4% to 31.9% among the 30 Networks (p<0.001). Adjusting for their patient characteristics did not appreciably reduce Network-level variation, with adjusted IR rates still ranging from 8.0% to 29.4% (p<0.001). The risk-model also suggested that non-white women and those from more deprived areas were less likely to undergo immediate reconstruction. CONCLUSIONS: There is substantial regional variation in immediate reconstruction use in England that is not explained by the characteristics of the local patient population. English Cancer Networks should act to reduce this variation. They should also examine why rates of reconstruction differ between particular patient groups.