Assessing the sensitivity of placental growth factor and soluble fms-like tyrosine kinase 1 at 36 weeks' gestation to predict small-for-gestational-age infants or late-onset preeclampsia: a prospective nested case-control study

Background

Fetal growth restriction is a disorder of placental dysfunction with three to four-fold increased risk of stillbirth. Fetal growth restriction has pathophysiological features in common with preeclampsia. We hypothesised that angiogenesis-related factors in maternal plasma, known to predict preeclampsia, may also detect fetal growth restriction at 36 weeks’ gestation. We therefore set out to determine the diagnostic performance of soluble fms-like tyrosine kinase 1 (sFlt-1), placental growth factor (PlGF), and the sFlt-1:PlGF ratio, measured at 36 weeks’ gestation, in identifying women who subsequently give birth to small-for-gestational-age (SGA; birthweight <10th centile) infants. We also aimed to validate the predictive performance of the analytes for late-onset preeclampsia in a large independent, prospective cohort.

Methods

A nested 1:2 case-control study was performed including 102 cases of SGA infants and a matched group of 207 controls; and 39 cases of preeclampsia. We determined the diagnostic performance of each angiogenesis-related factor, and of their ratio, to detect SGA infants or preeclampsia, for a predetermined 10% false positive rate.

Results

Median plasma levels of PlGF at 36 weeks’ gestation were significantly lower in women who subsequently had SGA newborns (178.5 pg/ml) compared to normal birthweight controls (326.7 pg/ml, p < 0.0001). sFlt-1 was also higher among SGA cases, but this was not significant after women with concurrent preeclampsia were excluded. The sensitivity of PlGF to predict SGA infants was 28.8% for a 10% false positive rate. The sFlt-1:PlGF ratio demonstrated better sensitivity for preeclampsia than either analyte alone, detecting 69.2% of cases for a 10% false positive rate.

Conclusions

Plasma PlGF at 36 weeks’ gestation is significantly lower in women who subsequently deliver a SGA infant. While the sensitivity and specificity of PlGF currently limit clinical translation, our findings support a blood-based biomarker approach to detect late-onset fetal growth restriction. Thirty-six week sFlt-1:PlGF ratio predicts 69.2% of preeclampsia cases, and could be a useful screening test to triage antenatal surveillance.

Electronic supplementary material

The online version of this article (10.1186/s12884-018-1992-x) contains supplementary material, which is available to authorized users.

Prospective longitudinal assessment of the fetal left modified Myocardial Performance Index

INTRODUCTION

The fetal left modified Myocardial Performance Index (Mod-myocardial performance index (MPI)) is a measure of systolic versus diastolic time intervals obtained from a single cardiac cycle with ultrasound. It is a measure of global ventricular function and has been investigated for potential utility in fetal conditions associated with cardiac dysfunction.

OBJECTIVES

The objective of this study is to compare values from a precisely replicated fetal left Mod-MPI technique to published reference ranges.

METHODS

Three hundred and sixty-five nulliparae prospectively underwent fetal left Mod-MPI measurement at 27⁺⁰-29⁺⁰ and 35⁺⁰-37⁺⁰ weeks' gestation. Measurements from pregnancies complicated by gestational diabetes mellitus, preeclampsia, or a small-for-gestational-age (<10th centile) infant were excluded. Mod-MPI values were compared with three published references created using similar measurement techniques.

RESULTS

Compared with one selected reference, at 29⁺⁰ and 35⁺⁰-37⁺⁰ weeks' gestation, 90-100% of our values fell within the 5th-95th percentile range as expected. Thus, this reference range was validated for our population in late pregnancy. However, the expected level of concordance was not seen at 27⁺⁰-28⁺⁶ weeks'. The other two references to which we compared our Mod-MPI values demonstrated poor concordance, especially at 27⁺⁰-29⁺⁰ weeks'. Pearson interobserver correlation was also improved at 35⁺⁰-37⁺⁰ weeks' at 0.434, compared with 0.083 at 27⁺⁰-29⁺⁰ weeks' gestation.

CONCLUSIONS

Concordance and interobserver variability between our cohort and similar populations were both improved at 35⁺⁰-37⁺⁰ weeks' compared with 27⁺⁰-29⁺⁰ weeks' gestation. Overall, variable Mod-MPI reproducibility across gestations limits clinical application, especially earlier in pregnancy. Manual Mod-MPI measurement should be considered most reliable in late pregnancy until automated MPI measurement is possible.

Reduced growth velocity across the third trimester is associated with placental insufficiency in fetuses born at a normal birthweight: a prospective cohort study

BACKGROUND

While being small-for-gestational-age due to placental insufficiency is a major risk factor for stillbirth, 50% of stillbirths occur in appropriate-for-gestational-age (AGA, > 10th centile) fetuses. AGA fetuses are plausibly also at risk of stillbirth if placental insufficiency is present. Such fetuses may be expected to demonstrate declining growth trajectory across pregnancy, although they do not fall below the 10th centile before birth. We investigated whether reduced growth velocity in AGA fetuses is associated with antenatal, intrapartum and neonatal indicators of placental insufficiency.

METHODS

We performed a prospective cohort study of 308 nulliparous women who subsequently gave birth to AGA infants. Ultrasound was utilised at 28 and 36 weeks' gestation to determine estimated fetal weight (EFW) and abdominal circumference (AC). We correlated relative EFW and AC growth velocities with three clinical indicators of placental insufficiency, namely (1) fetal cerebroplacental ratio (CPR; CPR < 5th centile reflects placental resistance, and blood flow redistribution to the brain - a fetal response to hypoxia); (2) neonatal acidosis after the hypoxic challenge of labour (umbilical artery (UA) pH < 7.15 at birth); and (3) low neonatal body fat percentage (BF%, measured by air displacement plethysmography) reflecting reduced nutritional reserve in utero.

RESULTS

For each one centile reduction in EFW growth velocity between 28 and 36 weeks' gestation, there was a 2.4% increase in the odds of cerebral redistribution (CPR < 5th centile, odds ratio (OR) (95% confidence interval) = 1.024 (1.005-1.042), P = 0.012) and neonatal acidosis (UA pH < 7.15, OR = 1.024 (1.003-1.046), P = 0.023), and a 3.3% increase in the odds of low BF% (OR = 1.033 (1.001-1.067), P = 0.047). A decline in EFW of > 30 centiles between 28 and 36 weeks (compared to greater relative growth) was associated with cerebral redistribution (CPR < 5th centile relative risk (RR) = 2.80 (1.25-6.25), P = 0.026), and a decline of > 35 centiles was associated with neonatal acidosis (UA pH < 7.15 RR = 3.51 (1.40-8.77), P = 0.030). Similar associations were identified between low AC growth velocity and clinical indicators of placental insufficiency.

CONCLUSIONS

Reduced growth velocity between 28 and 36 weeks' gestation among fetuses born AGA is associated with antenatal, intrapartum and neonatal indicators of placental insufficiency. These fetuses potentially represent an important unrecognised cohort at increased risk of stillbirth and may warrant more intensive antenatal surveillance.

Shining light in dark corners: diagnosis and management of late-onset fetal growth restriction

Fetal growth restriction (FGR) is the single biggest risk factor for stillbirth. In the absence of any effective treatment for fetal growth restriction, the mainstay of management is close surveillance and timely delivery. While such statements are almost self-evident, the daily clinical challenge of late-onset fetal growth restriction remains; the competing priorities of minimising stillbirth risk, while avoiding excessive obstetric intervention and the neonatal sequelae of iatrogenic preterm birth. This dilemma is made harder because the tools for late-onset FGR diagnosis and surveillance compare poorly to those used in early-onset FGR; screening tests in early pregnancy have limited predictive value; most cases escape clinical detection, a phenomenon set to worsen given the obesity epidemic; there is a failure of consensus on the definition of small for gestational age, and ancillary tools, such as umbilical artery Doppler--of value in identification of preterm FGR--are less useful in the late-preterm period and at term. Most importantly, the problem is common; 96% of all births occur after 32 weeks. This means a poor noise/signal ratio of any test or management algorithm will inevitably have large clinical consequences. Into such a dark corner, we cast some light; a summary on diagnostic criteria, new developments to improve the diagnosis of late-onset FGR and a suggested approach to management.

Incidence and prevalence of multiple sclerosis in the UK 1990-2010: a descriptive study in the General Practice Research Database

OBJECTIVES

To estimate the incidence and prevalence of multiple sclerosis (MS) by age and describe secular trends and geographic variations within the UK over the 20-year period between 1990 and 2010 and hence to provide updated information on the impact of MS throughout the UK.

DESIGN

A descriptive study.

SETTING

The study was carried out in the General Practice Research Database (GPRD), a primary care database representative of the UK population.

MAIN OUTCOME MEASURES

Incidence and prevalence of MS per 100 000 population. Secular and geographical trends in incidence and prevalence of MS.

RESULTS

The prevalence of MS recorded in GPRD increased by about 2.4% per year (95% CI 2.3% to 2.6%) reaching 285.8 per 100 000 in women (95% CI 278.7 to 293.1) and 113.1 per 100 000 in men (95% CI 108.6 to 117.7) by 2010. There was a consistent downward trend in incidence of MS reaching 11.52 per 100 000/year (95% CI 10.96 to 12.11) in women and 4.84 per 100 000/year (95% CI 4.54 to 5.16) in men by 2010. Peak incidence occurred between ages 40 and 50 years and maximum prevalence between ages 55 and 60 years. Women accounted for 72% of prevalent and 71% of incident cases. Scotland had the highest incidence and prevalence rates in the UK.

CONCLUSIONS

We estimate that 126 669 people were living with MS in the UK in 2010 (203.4 per 100 000 population) and that 6003 new cases were diagnosed that year (9.64 per 100 000/year). There is an increasing population living longer with MS, which has important implications for resource allocation for MS in the UK.

Hay fever symptoms and over-the-counter remedies: a community pharmacy study

There is poor understanding of patients' perceptions of hay fever symptoms, the factors which motivate them to purchase particular products and what properties they deem desirable in a remedy. This study aimed to increase understanding of patients' perceptions of hay fever symptoms and to investigate their perceptions of five non-sedating oral antihistamine products and a corticosteroid nasal spray. A sample of 249 patients was recruited from community pharmacies from June to August, 1995. Of these, 139 (56 per cent) returned questionnaires, of which 124 were valid for analysis. The most common symptoms experienced were nasal and ocular. The most common early warning sign of hay fever was sneezing (75; 21 per cent). Forty-three subjects (35 per cent) indicated there was less than half an hour between the first sign of an attack and developing all symptoms, and 87 (70 per cent) reported developing all symptoms in under two hours. For 45 subjects (36 per cent) the worst period for the attack was the morning. The most common way of treating a hay fever attack was by taking a remedy at the first sign of hay fever (70; 56 per cent). Seventy-six (61 per cent) used the remedy once daily and 120 (96 per cent) once or twice daily. Eighty-five (69 per cent) used the remedy every day of the week during an attack. A reduction in sneezing was the most common indicator that the remedy was working (50; 21 per cent). The most common reason for purchasing a remedy was the pharmacist's recommendation (45; 33 per cent). The most common reason for acquiring the remedy by over-the-counter (OTC) purchase was that it was more convenient than consulting a general medical practitioner (GP) (77; 42 per cent). The most common reason for liking a particular remedy was that it gave fast relief (35; 21 per cent). The most common reason for disliking a remedy was that it was expensive (21; 28 per cent). Most patients (108; 87 per cent) were either “very” or “fairly” satisfied with their remedy. The top three most important desired properties of an “ideal” hay fever remedy were that it was fast acting, gave long lasting relief and did not cause drowsiness.

Antiplatelet drug interactions

Both laboratory studies in healthy volunteers and clinical studies have suggested adverse interactions between antiplatelet drugs and other commonly used medications. Interactions described include those between aspirin and ibuprofen, aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), and the thienopyridine, clopidogrel, and drugs inhibiting CYP2C19, notably the proton pump inhibitors (PPI) omeprazole and esomeprazole. Other interactions between thienopyridines and CYP3A4/5 have also been reported for statins and calcium channel blockers. The ibuprofen/aspirin interaction is thought to be caused by ibuprofen blocking the access of aspirin to platelet cyclo-oxygenase. The thienopyridine interactions are caused by inhibition of microsomal enzymes that metabolize these pro-drugs to their active metabolites. We review the evidence for these interactions, assess their clinical importance and suggest strategies of how to deal with them in clinical practice. We conclude that ibuprofen is likely to interact with aspirin and reduce its anti-platelet action particularly in those patients who take ibuprofen chronically. This interaction is of greater relevance to those patients at high cardiovascular risk. A sensible strategy is to advise users of aspirin to avoid chronic ibuprofen or to ingest aspirin at least 2 h prior to ibuprofen. Clearly the use of NSAIDs that do not interact in this way is preferred. For the clopidogrel CYP2C19 and CYP3A4/5 interactions, there is good evidence that these interactions occur. However, there is less good evidence to support the clinical importance of these interactions. Again, a reasonable strategy is to avoid the chronic use of drugs that inhibit CYP2C19, notably PPIs, in subjects taking clopidogrel and use high dose H2 antagonists instead. Finally, anti-platelet agents probably interact with other drugs that affect platelet function such as selective serotonin reuptake inhibitors, and clinicians should probably judge patients taking such combination therapies as at high risk for bleeding.

The effects of lumiracoxib 100 mg once daily vs. ibuprofen 600 mg three times daily on the blood pressure profiles of hypertensive osteoarthritis patients taking different classes of antihypertensive agents

AIMS

To examine whether the blood pressure (BP) profiles of lumiracoxib and high-dose ibuprofen differed in patients treated with different classes of antihypertensive medications.

METHODS

A 4-week, multicentre, randomised, double-blind study has compared the effects of lumiracoxib 100 mg once daily (od) (n = 394) and ibuprofen 600 mg three times daily (tid) (n = 393) on ambulatory BP in osteoarthritis (OA) patients with controlled hypertension. Here, we present subgroup analyses for patients receiving different antihypertensive classes. The primary outcome was a comparison of the change in 24-h mean systolic ambulatory BP (MSABP) from baseline to week 4. Patients receiving angiotensin receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors (ACEIs) represented the largest subgroups receiving antihypertensive monotherapy.

RESULTS

For patients receiving an ARB monotherapy, the least squares mean (LSM) 24-h MSABP at week 4 fell with lumiracoxib 100 mg od and increased with ibuprofen 600 mg tid, creating an estimated treatment difference of 8.1 mmHg in favour of lumiracoxib (p < 0.001). For patients receiving an ACEI and a beta-blocker monotherapy, the estimated treatment difference was 8.2 mmHg (p < 0.001) and 5.8 mmHg (p = 0.002) in favour of lumiracoxib respectively. These treatment differences were greater than observed in the overall population (5.0 mmHg in favour of lumiracoxib). In patients receiving diuretics or calcium channel blockers, treatment differences in MSABP were smaller and not statistically significant, although they remained in favour of lumiracoxib.

CONCLUSION

Lumiracoxib 100 mg od resulted in less destabilisation of BP than high-dose ibuprofen 600 mg tid, and this effect was the greatest in subgroups treated with drugs blocking the renin-angiotensin system.

Association between allopurinol and mortality in heart failure patients: a long-term follow-up study

AIMS

The aim of the study was to explore the long-term effect of allopurinol on mortality and cardiovascular hospitalisations in heart failure (HF) patients.

METHODS

This is a population-based cohort study using a record-linkage database in Tayside, Scotland. A total of 4785 HF patients (4260 non-users, 267 incident users and 258 prevalent users) were studied between 1993 and 2002.

RESULTS

Compared with non-users, low-dose users in the incident group had a significant increased risk of all-cause mortality, cardiovascular mortality and cardiovascular recurrence (adjusted HR, 1.60, 95%CI 1.26-2.03; 1.70, 1.29-2.23 and 1.44, 1.01-2.07). For the prevalent users, the adjusted HR were 1.27, 0.98-1.64; 1.43, 1.07-1.90 and 1.27, 0.91-1.76 respectively. There was no increased risk of outcome for high-dose users when compared with non-users (adjusted HR, 1.18, 0.84-1.66; 1.14, 0.76-1.71 and 1.36, 0.88-2.10 for the incident users, and 0.86, 0.64-1.15; 0.90, 0.64-1.26; and 1.27, 0.93-1.74 for the prevalent users respectively). High-dose allopurinol was associated with reduced risk of all-course mortality for prevalent users when compared with low-dose (adjusted HR 0.65, 95%CI 0.42-0.99).

CONCLUSIONS

The prevalent high-dose allopurinol use had a lower risk of mortality than the prevalent low-dose use suggesting that allopurinol may be of benefit in HF patients.

Exercise blood pressure and endothelial dysfunction in hypertension

BACKGROUND

Hypertensive patients with persistent endothelial dysfunction have adverse cardiovascular prognosis. However, current methods aimed to assess endothelial dysfunction in those patients who possess clinical applicability. We hypothesised that such individuals could potentially be identified by an exaggerated systolic blood pressure (BP) response to a submaximal exercise.

METHODS

We studied 22 male patients with essential hypertension who were categorised into two age-matched groups depending on their exercise systolic BP (ExSBP) rise during the 3-min exercise step test; the exaggerated ExSBP group [hyper-responders (> or = 40 mmHg)] and the low ExSBP responder group [hypo-responders (< or = 20 mmHg)]. Eleven healthy volunteers matched for age were used as control. Clinic and daytime ambulatory BP were assessed after 14 days of anti-hypertensive treatment withdrawal, which were not significantly different between groups. Vascular reactivity in response to intra-arterial infusions of acetylcholine, N(G)-monomethyl-l-arginine (l-NMMA) and sodium nitroprusside was assessed using forearm venous occlusion plethysmography.

RESULTS

The hyper-responder group had significantly less forearm vasodilatation to acetylcholine compared with the hypo-responder group [percentage change in the forearm blood flow 125 (17) vs. 260 (28), mean (SEM); p < 0.001]. Similarly, the vasoconstrictive response to l-NMMA was significantly impaired in the hyper-responder group in comparison to the hypo-responder group [-30 (2) vs. -45 (4); p < 0.05]. In contrast, the vascular response to sodium nitroprusside was not different between groups suggesting preserved endothelial-independent vasodilatation.

CONCLUSIONS

Despite similar ambulatory and office BP, the exaggerated ExSBP group had significantly worse endothelial function compared with the low ExSBP responder group. This simple and non-invasive test may be useful in routine clinical practice to aid risk stratification in hypertensive patients.

The association between coeliac disease and cardiovascular disease

BACKGROUND

Coeliac disease is more prevalent than was previously thought. The association between coeliac disease and cardiovascular outcome is not clear.

AIM

To investigate whether coeliac disease patients have an increased risk of cardiovascular events.

METHODS

A community-based cohort study using a record-linkage database. Three hundred and sixty-seven coeliac patients identified by a positive antiendomysial antibody test or a diagnosis with small bowel biopsy, and 5537 subjects who were tested and had a negative coeliac immunology, were included in the study.

RESULTS

The crude rates of cardiovascular events were 9.5 per 1000 person-years (95% CI: 4.4-14.6) in the coeliac cohort and 8.9 per 1000 person-years (95% CI: 7.6-10.3) in the antiendomysial antibody-negative cohort. Compared with the antiendomysial antibody-negative cohort, the adjusted relative risk of cardiovascular events for coeliac cohort was 1.9 (95% CI: 1.00-3.60). When we excluded patients who had previous hospitalization for cardiovascular disease, the adjusted relative risk was 2.5 (95% CI: 1.22-5.01). The use of any cardiovascular drugs prior to and after entry to the study were 36% and 29% for the coeliac cohort (P = 0.05), and 34% and 26% for the antiendomysial antibody-negative cohort (P < 0.01).

CONCLUSION

Our findings suggest that coeliac disease seems to be associated with an increased risk of cardiovascular outcome.

Impact on mortality following first acute myocardial infarction of distance between home and hospital: cohort study

Objective:

To investigate the effect of distance between home and acute hospital on mortality outcome of patients experiencing an incident myocardial infarction (MI).

Design:

Cohort study using a record linkage database.

Setting:

Tayside, Scotland, UK.

Patients:

10 541 patients with incident acute MI between 1994 and 2003 were identified from Tayside hospital discharge data and from death certification data.

Main outcome measures:

MI mortality in the community, all-cause mortality in hospital and all-cause mortality during follow-up.

Results:

4133 subjects died following incident MI in the community (that is, were not hospitalised), 6408 patients survived to be hospitalised and 1010 of these (15.8%) died in hospital. Of 5398 discharged from hospital, 1907 (35.3%) died during a median of 3.2 years of follow-up. After adjustment for rurality and other known risk factors, distance between home and admitting hospital was significantly associated with increased mortality both before hospital admission (adjusted odds ratio (OR), 2.05, 95% CI 1.00 to 4.21 for >9 miles and 1.46, 1.09 to 1.95 for 3–9 miles when compared to <3 miles) and after hospitalisation (adjusted hazard ratio (HR) 1.90, 1.19 to 3.02 and 1.27, 0.96 to 1.68). However, there was no effect of distance on in-hospital mortality (adjusted OR 0.95, 0.45 to 2.03 and 1.02, 0.66 to 1.58).

Conclusion:

The distance between home and hospital of admission may predict mortality in subjects experiencing a first acute MI. This association was found both before and after hospitalisation. Further studies are needed to explore the reasons for this association. However these data provide support for policies that locate services for acute MI closer to where patients live.

Treatment patterns of hypertension and dyslipidaemia in hypertensive patients at higher and lower risk of cardiovascular disease in primary care in the United Kingdom

Few studies have investigated the presence of dyslipidaemia in hypertensive individuals. In addition, few data exist on the concurrent treatment of both conditions for the prevention of cardiovascular disease (CVD). This retrospective cohort study examined treatment patterns for hypertension and dyslipidaemia among hypertensive patients in UK primary care. We defined a population of patients aged > or =40 years from the UK General Practice Research Database. Hypertensive individuals with > or =3 additional cardiovascular risk factors (ARFs) were compared with a cohort comprising hypertensive patients with < or =2 ARFs. We analysed the prevalence of risk factors and the prevalence and incidence of treatment for hypertension, dyslipidaemia and for both conditions between January 1997 and December 2001. A total of 117 840 hypertensive patients were identified (23 655 with > or =3 ARFs, 94 185 with < or =2 ARFs) in 1997; in 2001, the number diagnosed as hypertensive was 133 683 (40 248 > or =3 ARFs, 93 435 < or =2 ARFs). The prevalence of antihypertensive treatment in the hypertensive patients with > or =3 ARFs increased during the study. In 2001, approximately one-third of hypertensive patients with > or =3 ARFs were not receiving antihypertensives. Among those patients who received such treatment, the majority received > or =2 separate agents in accordance with current guidelines. Treatment for concurrent hypertension and dyslipidaemia was initiated in <8% of patients with hypertension and > or =3 ARFs in each year. These findings demonstrate the under-recognition/undertreatment of cardiovascular risk factors in UK primary care among patients at risk of CVD.

Effectiveness of two statin prescribing strategies with respect to adherence and cardiovascular outcomes: observational study

BACKGROUND

There is considerable evidence that statins can reduce cardiovascular events. Currently high-risk patients are treated to a target cholesterol concentration. An alternative prescribing strategy (the 'fire-and-forget' approach) would instead deploy low-dose statins more widely. It has been suggested that for the same cost this approach might prevent more cardiovascular events. We have compared the treat-to-target and fire-and-forget statin prescribing strategies with respect to adherence and cardiovascular outcomes.

METHODS

We used a population-based record-linkage database containing several data sets linked by a unique patient identifier. We identified two cohorts of patients. Patients in the treat-to-target cohort were prescribed a statin, and subsequent measurement of their cholesterol was followed by upward titration of their statin dose if necessary. Patients in the fire-and-forget cohort were prescribed a statin, but no further cholesterol measurement was observed during the follow-up period.

FINDINGS

Adherence to statin treatment in patients treated to target was significantly better than in patients treated on a fire-and-forget basis (adjusted odds ratio 2.51, 95%CI 2.26-2.78). We found a lower cardiovascular disease (CVD) event rate in patients treated to target than in fire-and-forget patients (hazard ratio of CVD or cardiovascular death 0.41 (0.35-0.48) even after adjustment was made for adherence and baseline CVD risk).

INTERPRETATION

Our findings suggest that adherence to statins is worse in patients treated on a fire-and-forget basis than in patients treated to a target cholesterol concentration, and that this prescribing strategy is associated with worse cardiovascular outcomes.

Impact on cardiovascular events of increasing high density lipoprotein cholesterol with and without lipid lowering drugs

OBJECTIVE

To estimate the impact on cardiovascular events of changes in high density lipoprotein (HDL) adjusted for changes in total cholesterol.

DESIGN

Cohort study based on a record linkage database.

SETTING

Community study in Tayside, Scotland, UK.

PATIENTS

18,815 patients were identified for the study between 1989 and 2001.

MAIN OUTCOME MEASURES

Cardiovascular events.

RESULTS

5510 patients taking lipid lowering treatment who had not been hospitalised previously for cardiovascular disease had 314 cardiovascular events recorded (9407 person years of follow up). Patients whose HDL rose by > 20% were less likely to have an event (23.5/1000 person years, 95% confidence interval (CI) 17.3 to 29.6) compared with patients whose HDL did not rise (42.6/1000 person years, 95% CI 35.5 to 49.7, adjusted relative risk 0.60, 95% CI 0.44 to 0.83). HDL change and cardiovascular outcome were not significantly associated among patients who had been hospitalised previously for cardiovascular disease or among patients who were not taking lipid lowering drugs.

CONCLUSION

In this study a rise in HDL independently predicted reduced cardiovascular risk in patients taking lipid lowering treatment who had not been hospitalised previously for cardiovascular disease.

Application of a propensity score to adjust for channelling bias with NSAIDs

PURPOSE

To compare the relative risks of upper GI haemorrhage (UGIH) in users of Newer versus Older, non-specific NSAIDs when adjusted for channelling bias by regression on individual covariates, a propensity score and both.

METHODS

Cohort study of patients prescribed NSAIDs between June 1987 and January 2000. Exposure to Newer and Older non-specific NSAIDs was identified, and risk factors evaluated for each patient. Results of multiple covariate analyses and the propensity scoring technique to assess potential channelling bias in comparisons between Newer and Older non-specific NSAIDs were compared.

RESULTS

This study included 7.1 thousand patient years (tpy) exposure to meloxicam, 1.6 tpy exposure to coxibs, and 628 tpy exposure to Older non-specific NSAIDs. Patients receiving Newer NSAIDs were older, more likely to have a history of GI symptoms, and at higher risk for GI complications. Adjusting for these risk factors reduced the relative risks of UGIH on meloxicam and coxibs versus Older non-specific NSAIDs to 0.84 (95%CI 0.60, 1.17) and 0.36 (0.14, 0.97) respectively.

CONCLUSIONS

Channelling towards high GI risk patients occurred in the prescribing of Newer NSAIDs. Propensity scores highlighted the markedly different risk profiles of users of Newer and Older non-specific NSAID. Correcting for channelling bias, coxib exposure, but not meloxicam exposure, was associated with less UGIH than Older non-specific NSAID exposure. In the present study, corrections made by regression on a propensity score and on individual covariates were similar.

The thyroid epidemiology, audit, and research study: thyroid dysfunction in the general population

The objective of this study was to define the level of treated thyroid dysfunction in a complete and representative population base in an area of sufficient dietary iodine intake. We used record-linkage technology to retrospectively identify subjects treated for hyperthyroidism or hypothyroidism in the general population of Tayside, Scotland from 1 January 1993 to 30 April 1997. Thyroid status was ascertained by record linkage of patient-level datasets containing details of treatments for hyperthyroidism and hypothyroidism. We identified 620 incident cases of hyperthyroidism, an incidence rate of 0.77/1000 x yr [95% confidence interval (CI), 0.70-0.84] in females and 0.14/1000 x yr (95% CI, 0.12-0.18) in males. There were 3,486 incident cases of diagnosed primary hypothyroidism, an incidence rate of 4.98/1000 x yr (95% CI, 4.81-5.17) in females and 0.88/1000 x yr (95% CI, 0.80-0.96) in males. For both hyperthyroidism and hypothyroidism, the incidence increased with age, and females were affected two to eight times more than males across the age range. The midyear point prevalence of all-cause hypothyroidism rose from 2.2% in 1993 to 3.0% in 1996. The level of thyroid dysfunction in Tayside, Scotland is higher than previously reported, and it increased from 1993 to 1996.

Do H2-receptor antagonists cause acute pancreatitis?

The aim of this study was to investigate the association between H(2)-receptor antagonists and acute pancreatitis. The automated database of the Medicines Monitoring Unit (MEMO) was used to carry out a case-control study, supplemented with information on possible confounding factors from hospital and GP medical records. Cases were patients hospitalized with a computerized diagnosis of acute pancreatitis, and two sets of controls were drawn from (1) the study population and from (2) the same GP practice as the case. Current or 60-day exposure to cimetidine and ranitidine was analysed. In adjusted analyses, cimetidine exposure and ranitidine exposure were associated with an increased risk of hospitalization for acute pancreatitis, as were alcohol abuse and cholelithiasis. The risks were lower in unadjusted analyses, suggesting that the association is confounded, although they did not disappear completely. A possible explanation is that data on confounding were incomplete. This study cannot discount the existence of an association between H(2)-antagonists and acute pancreatitis, and highlights the difficulties involved in obtaining complete and accurate data on confounding factors that are not collected routinely.

Do H2-receptor antagonists cause acute pancreatitis?

The aim of this study was to investigate the association between H(2)-receptor antagonists and acute pancreatitis. The automated database of the Medicines Monitoring Unit (MEMO) was used to carry out a case-control study, supplemented with information on possible confounding factors from hospital and GP medical records. Cases were patients hospitalized with a computerized diagnosis of acute pancreatitis, and two sets of controls were drawn from (1) the study population and from (2) the same GP practice as the case. Current or 60-day exposure to cimetidine and ranitidine was analysed. In adjusted analyses, cimetidine exposure and ranitidine exposure were associated with an increased risk of hospitalization for acute pancreatitis, as were alcohol abuse and cholelithiasis. The risks were lower in unadjusted analyses, suggesting that the association is confounded, although they did not disappear completely. A possible explanation is that data on confounding were incomplete. This study cannot discount the existence of an association between H(2)-antagonists and acute pancreatitis, and highlights the difficulties involved in obtaining complete and accurate data on confounding factors that are not collected routinely.

A study to determine the sensitivity and specificity of hospital discharge diagnosis data used in the MICA study

AIMS

To determine the sensitivity and specificity of each ICD9 code for a diagnosis of definite or possible myocardial infarction (MI) from the perspective of the Myocardial Infarction Causality Study (MICA) and to use these data to estimate the likely number of MICA cases in Scotland that would be undetected were these codes omitted from the study.

SETTING

Women resident and registered with general practitioners in the Tayside region of Scotland between October 1993 and October 1995.

METHOD

All SMR1 records of Tayside hospitalizations containing ICD9 (International Classification of Diseases, ninth revision) codes for myocardial infarction (410) or possible myocardial infarction (411, 412, 413, 414, 427.4, 427.5, 786.5) were identified for women aged between 16 and 44 years between 1 October 1993 and 15 October 1995. Original case records were sought and each episode abstracted using a predefined form. Records were independently scrutinized by two consultant cardiologists blinded to the SMR1 code. Cases were categorized as definite MI, possible MI or unlikely MI. Where there was disagreement between the two cardiologists, the profiles for such events were examined by a third cardiologist who acted as the final adjudicator. The adjudicator's verdict was, in this study, considered dominant. The sensitivity, specificity and positive predictive value of each ICD9 code was determined.

RESULTS

Two hundred and fifty-three women fulfilled the SMR1 search criteria. Case records of 204 (81%) were retrieved but four case records contained no data on the admission of interest and were classified as invalid. Forty-six of the 200 remaining patients were ineligible for the MICA study leaving 154 records for evaluation. There were 12 patients who had a discharge code for MI (ICD9 410). Of these, 11 were judged as a definite MI by both cardiologists. One event (discharge code ICD9 410) was judged as 'possible' by one cardiologist and 'unlikely' by the other. The adjudicator subsequently judged this event as 'definite'. Another six events were subsequently judged as 'possible'. Thus, after adjudication, 12 cases of definite MI and six cases of 'possible' MI were identified. The sensitivity and specificity of ICD9 code 410 was 67% and 100% respectively. The positive predictive value was 100%. The sensitivity of code 411 was 5.6%. The specificity was 99% and the positive predictive value was 50%. Code 413 had a sensitivity of 5.6% with a specificity of 94% and a positive predictive value of 9.1%. Code 414 also had a sensitivity of 5.6%. The specificity was 86% and the positive predictive value was 4.5%. Code 786.5 had a sensitivity of 17%, a specificity of 23% and a positive predictive value of 2.5%. Code 427.5 failed to identify any definite or possible cases.

CONCLUSIONS

In the MICA Study, ICD9 code 410 was found to be the most robust. All 12 patients judged to have had a definite MI had the appropriate discharge code (ICD9 410). The six patients judged to have had a possible MI all had discharge codes other than that for MI (410). However, identifying these six patients required the validation of a further 160 events-giving a combined sensitivity of 33%, a specificity of 0% and a positive predictive value of only 3.8%. The use of ICD9 codes 411, 413, 414, 427.5 and 786.5 must, therefore, only be employed when circumstances fully justify the additional workload.