Non-steroidal anti-inflammatory drugs and the risk of head and neck cancer: A case-control analysis

Non-steroidal anti-inflammatory drugs (NSAIDs) and acetylsalicylic acid (aspirin) have been associated with a reduced risk for certain cancers. We explored the association between use of NSAIDs and the risk of head and neck cancer (HNC). We conducted a case-control analysis in the UK-based Clinical Practice Research Datalink (CPRD) among people below the age of 90 years with incident HNC between 1995 and 2013. Six controls per case were matched on age, sex, calendar time, general practice, and number of years of active history in the CPRD prior to the HNC diagnosis. Other potential confounders including comorbidities and comedication were also evaluated, and we adjusted our final analyses for BMI, smoking and alcohol consumption. Our analyses included 2,745 HNC cases and 16,470 controls. Aspirin or NSAID use overall did not significantly change the HNC risk. However, patients with six or more prescriptions for ibuprofen were at a statistically significantly reduced risk for HNC (adjusted OR 0.59, 95% CI 0.37-0.94). The HNC risk tended to decrease with increasing cumulative exposure to ibuprofen, and to be more pronounced for cancer of the larynx. To conclude, in this large population-based observational study we found a decreased risk for HNC associated with regular use of ibuprofen.

Comparative Safety of Testosterone Dosage Forms

IMPORTANCE

Increases in testosterone use and mixed reports of adverse events have raised concerns about the cardiovascular safety of testosterone. Testosterone is available in several delivery mechanisms with varying pharmacokinetics; injections cause spikes in testosterone levels, and transdermal patches and gels cause more subtle but sustained increases. The comparative cardiovascular safety of gels, injections, and patches has not been studied.

OBJECTIVE

To determine the comparative cardiovascular safety of testosterone injections, patches, and gels.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study was conducted using administrative claims from a commercially insured (January 1, 2000, to December 31, 2012) and Medicare (January 1, 2007, to December 31, 2010) population in the United States and general practitioner records from the United Kingdom (January 1, 2000, to June 30, 2012). Participants included men (aged ≥18 years) who initiated use of testosterone patches, gels, or injections following 180 days with no testosterone use. Our analysis was conducted from December 11, 2013, to November 12, 2014.

EXPOSURES

New initiation of a testosterone dosage form, with use monitored for up to 1 year.

MAIN OUTCOMES AND MEASURES

Inpatient or outpatient medical records, diagnoses, or claims for cardiovascular and cerebrovascular events including myocardial infarction (MI), unstable angina, stroke, and composite acute event (MI, unstable angina, or stroke); venous thromboembolism (VTE); mortality; and all-cause hospitalization.

RESULTS

We identified 544,115 testosterone initiators between the 3 data sets: 37.4% injection, 6.9% patch, and 55.8% gel. The majority of men in the Medicare cohort were injection initiators (51.2%), most in the US commercially insured population were gel initiators (56.5%), and the UK database included equal proportions of injections and gel users (approximately 41%). With analysis conducted using hazard ratios and 95% CIs, compared with men using gels, injection initiators had higher hazards of cardiovascular events (ie, MI, unstable angina, and stroke) (1.26; 1.18-1.35), hospitalization (1.16; 1.13-1.19), and death (1.34; 1.15-1.56) but not VTE (0.92; 0.76-1.11). Compared with gels, patches did not confer increased hazards of cardiovascular events (1.10; 0.94-1.29), hospitalization (1.04; 1.00-1.08), death (1.02; 0.77-1.33), or VTE (1.08; 0.79-1.47).

CONCLUSIONS AND RELEVANCE

Testosterone injections were associated with a greater risk of cardiovascular events, hospitalizations, and deaths compared with gels. Patches and gels had similar risk profiles. However, this study did not assess whether patients met criteria for use of testosterone and did not assess the safety of testosterone among users compared with nonusers of the drug.

Antipsychotic drug use and the risk of seizures: follow-up study with a nested case-control analysis

OBJECTIVE

To investigate the association between antipsychotic drug use and the development of first-time seizures in patients with schizophrenia, affective disorders, or dementia.

METHODS

We used data from the UK-based Clinical Practice Research Datalink database to conduct a follow-up study with a nested case-control analysis between 1998 and 2013. We identified patients with schizophrenia, affective disorders, or dementia, and estimated incidence rates of seizures among users of four antipsychotic drug subclasses, defined according to existing hypotheses on their seizure-inducing potential (1, olanzapine or quetiapine; 2, amisulpride, aripiprazole, risperidone, or sulpiride; 3, low-to-medium potency first-generation antipsychotic drugs [chlorpromazine, zuclopenthixol, flupenthixol, pericyazine, promazine, thioridazine]; 4, medium-to-high potency first-generation antipsychotic drugs [haloperidol, prochlorperazine, trifluoperazine]), and among those who did not use antipsychotic drugs. To adjust for confounding, we estimated odds ratios for seizures separately among patients with affective disorders or dementia, stratified by antipsychotic drug use and timing of use.

RESULTS

In the total cohort of 60,121 patients (who had schizophrenia, affective disorders, or dementia), the incidence rate of seizures per 10,000 person-years was 32.6 (95 % confidence interval [CI] 22.6-42.6) in users of olanzapine or quetiapine, 24.1 (95 % CI 13.2-34.9) in users of amisulpride, aripiprazole, risperidone, or sulpiride, 49.4 (95 % CI 27.7-71.0) in users of low-to-medium potency antipsychotic drugs, 59.1 (95 % CI 40.1-78.2) in users of medium-to-high potency antipsychotic drugs, and 11.7 (95 % CI 10.0-13.4) in non-users of antipsychotic drugs. Patients with dementia had significantly higher incidence rates of first-time seizures compared with patients with affective disorders, irrespective of antipsychotic drug use. In patients with affective disorders, current use of medium-to-high potency first-generation antipsychotic drugs was associated with an increased risk of seizures (adjusted odds ratio 2.51 [95 % CI 1.51-4.18]) compared with non-use, while use of other antipsychotic drugs was not associated with seizures. In patients with dementia, current use of olanzapine or quetiapine (adjusted odds ratio 2.37 [95 % CI 1.35-4.15]), low-to-medium potency first-generation antipsychotic drugs (adjusted odds ratio 3.08 [95 % CI 1.34-7.08]), and medium-to-high potency first-generation antipsychotic drugs (adjusted odds ratio 2.24 [95 % CI 1.05-4.81]) was associated with an increased risk of seizures compared with non-use, but current use of amisulpride, aripiprazole, risperidone, or sulpiride (adjusted odds ratio 0.92 [95 % CI 0.48-1.75]) was not. Use of antipsychotic drugs in patients with schizophrenia could not be investigated because of small numbers.

CONCLUSIONS

Current use of medium-to-high potency first-generation antipsychotic drugs was associated with a 2.5-fold increased risk of seizures compared with non-use of antipsychotic drugs in patients with affective disorders. In these patients, current use of all other antipsychotic drug subclasses was not associated with seizures. In patients with dementia, current and past use of all antipsychotic drug subclasses, except amisulpride, aripiprazole, risperidone, or sulpiride, was associated with an increased risk of seizures.

Diabetes, use of antidiabetic drugs, and the risk of glioma

BACKGROUND

Prior epidemiologic studies suggest inverse relations between diabetes and glioma risk, but the underlying mechanisms, including use of antidiabetic drugs, are unknown.

METHODS

We therefore performed a matched case-control analysis using the Clinical Practice Research Datalink (CPRD). We identified incident glioma cases diagnosed between 1995 and 2012 and matched each case with 10 controls on age, gender, calendar time, general practice, and years of active history in the CPRD. We performed conditional logistic regression to estimate odds ratios (ORs) with 95% CIs, adjusted for body mass index and smoking.

RESULTS

We identified 2005 cases and 20 050 controls. Diabetes was associated with decreased risk of glioma (OR = 0.74; 95% CI = 0.60-0.93), particularly glioblastoma (OR = 0.69; 95% CI = 0.51-0.94). Glioblastoma risk reduction was markedly pronounced among diabetic men (OR = 0.60; 95% CI = 0.40-0.90), most apparently for those with diabetes of long-term duration (OR for >5 vs 0 y = 0.46; 95% CI = 0.26-0.82) or poor glycemic control (OR for HbA1c ≥ 8 vs <6.5% = 0.20; 95% CI = 0.06-0.70). In contrast, the effect of diabetes on glioblastoma risk was absent among women (OR = 0.85; 95% CI = 0.53-1.36). No significant associations with glioma were found for use of metformin (OR for ≥ 30 vs 0 prescriptions = 0.72; 95% CI = 0.38-1.39), sulfonylureas (OR = 0.71; 95% CI = 0.39-1.30), or insulin (OR = 0.79; 95% CI = 0.37-1.69).

CONCLUSIONS

Antidiabetic treatment appears to be unrelated to glioma, but long-term diabetes duration and increased HbA1c both show decreased glioma risk. Stronger findings in men than women suggest low androgen levels concurrent with diabetes as a biologic mechanism.

The association between psychiatric diseases, psychotropic drugs and the risk of incident rosacea

BACKGROUND

Psychological conditions, such as traumatic events or stress, have been discussed controversially as aetiological factors for rosacea.

OBJECTIVES

To assess the association between diagnosed depression, other affective disorders or schizophrenia and subsequent incident rosacea. We further aimed at evaluating the possible role of various psychotropic drugs within this association.

METHODS

We conducted a matched case-control study of psychiatric diseases and incident rosacea, stratified by exposure to various psychotropic drugs, using the UK-based General Practice Research Database. Cases had a first diagnosis of rosacea recorded between 1995 and 2009. Each case was matched to one control on age, sex, general practice and years of history on the database.

RESULTS

A history of depression or other affective disorders was not associated with an increased risk of developing rosacea; lithium was the only antidepressant drug that significantly altered this association. Current long-term use of lithium was associated with a decreased odds ratio (OR) of 0·58 [95% confidence interval (CI) 0·38-0·88] among people without a schizophrenia diagnosis (with or without affective disorders), compared with people not exposed to lithium. Patients with diagnosed schizophrenia revealed a decreased rosacea risk (OR 0·71, 95% CI 0·60-0·91), independent of antipsychotic drug use.

CONCLUSIONS

Depression or other affective disorders were not associated with incident rosacea, whereas patients with schizophrenia were at a decreased risk of this skin disease in our study population. The materially decreased risk of rosacea among people with chronic lithium exposure may lead to new insights into the pathomechanism of rosacea.

Oral and inhaled glucocorticoid use and risk of Achilles or biceps tendon rupture: a population-based case-control study

BACKGROUND

Tendinotoxicity of glucocorticoids (GC) has been shown, but evidence on how this translates into clinical practice remains scarce.

OBJECTIVES

To explore the association between oral or inhaled GC use and the risk of Achilles or biceps tendon rupture (ATR/BTR).

METHODS

We identified patients aged 18 to 89 years with incident ATR or BTR (1995-2013) for a matched (1:4) case-control analysis using the UK-based Clinical Practice Research Datalink. We stratified oral GC use by indication, timing and duration of use, continuous versus intermittent use, cumulative dose, and average daily dose. We stratified inhaled GC use by timing and number of prescriptions.

RESULTS

Among 8,202 cases, we observed increased odds ratios (ORs) around 3.0 for continuous oral GC use, which declined shortly after therapy cessation (similarly across indications). Odds ratios increased with average daily dose (≥ 10 mg/day, OR 4.05, 95% CI 2.32-7.08) and were elevated after one cycle of high-dose oral GC (≥ 20 mg/day). There was no effect of inhaled GC at any level of exposure.

CONCLUSION

Our results provide evidence that oral GC therapy increases the risk of tendon rupture in a dose-response relationship. A single short-term high-dose GC treatment course may be sufficient transiently to increase the risk of tendon rupture.

Nonsteroidal anti-inflammatory drugs and the risk of nonmelanoma skin cancer

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been assigned a promising role in the chemoprevention of various malignancies. However, epidemiological data on the association between NSAID use and nonmelanoma skin cancer (NMSC) are limited. To explore whether patients regularly exposed to systemic NSAIDs are at a reduced risk of basal cell carcinoma (BCC) or squamous cell carcinoma (SCC), we conducted a population-based case-control analysis using the Clinical Practice Research Datalink, a United Kingdom primary care database. We identified 65,398 patients with incident BCC and 7,864 patients with incident SCC diagnosed between 1995 and 2013 and matched 1 and 4 NMSC-free controls to each BCC and SCC case, respectively, on age, sex, general practice, calendar time and years of history in the database. We compared prior NSAID exposure between cases and controls using multivariate conditional logistic regression analyses controlling for several potential confounders. Overall, we found no association between NSAID use and BCC, but when looking exclusively at users of single NSAID substances there was a suggestion of a reduced BCC risk in regular users of aspirin and ibuprofen (adjusted odds ratio [adj. OR]: 0.92, 95% confidence interval [CI]: 0.85-0.99 and adj. OR: 0.61, 95% CI: 0.48-0.78, respectively). The risk of SCC was slightly decreased in regular users of any NSAIDs (adj. OR: 0.89, 95% CI: 0.82-0.97), with the strongest risk reduction observed in current users of coxibs (adj. OR: 0.77, 95% CI: 0.62-0.95). These findings provide evidence that patients predisposed to NMSC might benefit from chemoprevention with NSAIDs.

Metformin and the risk of head and neck cancer: a case-control analysis

AIMS

Metformin use has been associated with a decreased risk of some cancers, although data on head and neck cancer (HNC) are scarce. We explored the relation between the use of antidiabetic drugs and the risk of HNC.

METHODS

We conducted a case-control analysis in the UK-based Clinical Practice Research Datalink (CPRD) of people with incident HNC between 1995 and 2013 below the age of 90 years. Six controls per case were matched on age, sex, calendar time, general practice and number of years of active history in the CPRD prior to the index date. Other potential confounders including body mass index (BMI), smoking, alcohol consumption and comorbidities were also evaluated. The final analyses were adjusted for BMI, smoking and diabetes mellitus (or diabetes duration in a sensitivity analysis). Results are presented as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

Use of metformin was neither associated with a statistically significant altered risk of HNC overall (1-29 prescriptions: adjusted OR 0.87, 95% CI 0.61-1.24 and ≥ 30 prescriptions adjusted OR 0.80, 95% CI 0.53-1.22), nor was long-term use of sulphonylureas (adjusted OR 0.87, 95% CI 0.59-1.30), or any insulin use (adjusted OR 0.92, 95% CI 0.63-1.35). However, we found a (statistically non-significant) decreased risk of laryngeal cancer associated with long-term metformin use (adjusted OR 0.41, 95% CI 0.17-1.03).

CONCLUSIONS

In this population-based study, the use of antidiabetic drugs was not associated with a materially altered risk of HNC. Our data suggest a protective effect of long-term metformin use for laryngeal cancer.

Trends in incidence and medical resource utilisation in patients with chronic lymphocytic leukaemia: insights from the UK Clinical Practice Research Datalink (CPRD)

Chronic lymphocytic leukaemia (CLL) is the most common leukaemia in European adults. We aimed to evaluate time trends in CLL incidence and medical resource utilisation of CLL patients in the UK. We conducted a retrospective, observational cohort analysis using the UK Clinical Practice Research Datalink (CPRD) comprising mainly primary care data. We included adult patients with newly diagnosed CLL between January 2000 and June 2012. Descriptive and trend analyses of CLL incidence and medical resource utilisation were performed. A total of 2576 patients with CLL met the eligibility criteria. At diagnosis, the majority of patients (71.7 %) were above 65 years of age. The European age-standardised CLL incidence rate in the CPRD was 6.2/100,000 (95 % confidence interval [CI] 6.0, 6.5/100,000) person-years. There was no statistically significant increase over time. The CLL patients had on average 74.6 general practitioner visits during a median follow-up of 3.3 years. Between 2000 and 2012, the average number of recorded hospitalisations and referrals per year corrected for duration of follow-up significantly (p < 0.001) increased by 8.1 % (95 % CI 6.8 %, 9.3 %) and 16.4 % (95 % CI 15.4 %, 17.3 %), respectively. Referrals and hospitalisations in the second year compared to the first year following the CLL diagnosis significantly decreased. CLL incidence rates in the CPRD were stable over the period from 2000 to 2012. Medical resource utilisation in UK primary care was well documented, but further research is needed to describe secondary and tertiary care medical resource utilisation e.g. chemotherapy administration, which is inadequately captured in the CPRD.

Incidence of and risk factors for severe hypoglycaemia in treated type 2 diabetes mellitus patients in the UK--a nested case-control analysis

AIMS

To assess incidence rates (IRs) of and identify risk factors for incident severe hypoglycaemia in patients with type 2 diabetes newly treated with antidiabetic drugs.

METHODS

Using the UK-based General Practice Research Database, we performed a retrospective cohort study between 1994 and 2011 and a nested case-control analysis. Ten controls from the population at risk were matched to each case with a recorded severe hypoglycaemia during follow-up on general practice, years of history in the database and calendar time. Using multivariate conditional logistic regression analyses, we adjusted for potential confounders.

RESULTS

Of 130,761 patients with newly treated type 2 diabetes (mean age 61.7 ± 13.0 years), 690 (0.5%) had an incident episode of severe hypoglycaemia recorded [estimated IR 11.97 (95% confidence interval, CI, 11.11-12.90) per 10,000 person-years (PYs)]. The IR was markedly higher in insulin users [49.64 (95% CI, 44.08-55.89) per 10,000 PYs] than in patients not using insulin [8.03 (95% CI, 7.30-8.84) per 10,000 PYs]. Based on results of the nested case-control analysis increasing age [≥ 75 vs. 20-59 years; adjusted odds ratio (OR), 2.27; 95% CI, 1.65-3.12], cognitive impairment/dementia (adjusted OR, 2.00; 95% CI, 1.37-2.91), renal failure (adjusted OR, 1.34; 95% CI, 1.04-1.71), current use of sulphonylureas (adjusted OR, 4.45; 95% CI, 3.53-5.60) and current insulin use (adjusted OR, 11.83; 95% CI, 9.00-15.54) were all associated with an increased risk of severe hypoglycaemia.

CONCLUSIONS

Severe hypoglycaemia was recorded in 12 cases per 10,000 PYs. Risk factors for severe hypoglycaemia included increasing age, renal failure, cognitive impairment/dementia, and current use of insulin or sulphonylureas.

Poorly controlled type 2 diabetes mellitus is associated with a decreased risk of incident gout: a population-based case-control study

OBJECTIVE

The aim of this study was to explore the risk of incident gout in patients with type 2 diabetes mellitus (T2DM) in association with diabetes duration, diabetes severity and antidiabetic drug treatment.

METHODS

We conducted a case-control study in patients with T2DM using the UK-based Clinical Practice Research Datalink (CPRD). We identified case patients aged ≥18 years with an incident diagnosis of gout between 1990 and 2012. We matched to each case patient one gout-free control patient. We used conditional logistic regression analysis to calculate adjusted ORs (adj. ORs) with 95% CIs and adjusted our analyses for important potential confounders.

RESULTS

The study encompassed 7536 T2DM cases with a first-time diagnosis of gout. Compared to a diabetes duration <1 year, prolonged diabetes duration (1-3, 3-6, 7-9 and ≥10 years) was associated with decreased adj. ORs of 0.91 (95% CI 0.79 to 1.04), 0.76 (95% CI 0.67 to 0.86), 0.70 (95% CI 0.61 to 0.86), and 0.58 (95% CI 0.51 to 0.66), respectively. Compared to a reference A1C level of <7%, the risk estimates of increasing A1C levels (7.0-7.9, 8.0-8.9 and ≥9%) steadily decreased with adj. ORs of 0.79 (95% CI 0.72 to 0.86), 0.63 (95% CI 0.55 to 0.72), and 0.46 (95% CI 0.40 to 0.53), respectively. Neither use of insulin, metformin, nor sulfonylureas was associated with an altered risk of incident gout.

CONCLUSIONS

Increased A1C levels, but not use of antidiabetic drugs, was associated with a decreased risk of incident gout among patients with T2DM.

Use of diuretics and risk of incident gout: a population-based case-control study

OBJECTIVE

Use of diuretics has been associated with an increased risk of gout. Data on different types of diuretics are scarce. We undertook this study to investigate the association between use of loop diuretics, thiazide or thiazide-like diuretics, and potassium-sparing agents and the risk of developing incident gout.

METHODS

We conducted a retrospective population-based case-control analysis using the General Practice Research Database established in the UK. We identified case patients who were diagnosed as having incident gout between 1990 and 2010. One control patient was matched to each case patient for age, sex, general practice, calendar time, and years of active history in the database. We used conditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs), and we adjusted for potential confounders.

RESULTS

We identified 91,530 incident cases of gout and the same number of matched controls. Compared to past use of diuretics from each respective drug class, adjusted ORs for current use of loop diuretics, thiazide diuretics, thiazide-like diuretics, and potassium-sparing diuretics were 2.64 (95% CI 2.47-2.83), 1.70 (95% CI 1.62-1.79), 2.30 (95% CI 1.95-2.70), and 1.06 (95% CI 0.91-1.23), respectively. Combined use of loop diuretics and thiazide diuretics was associated with the highest relative risk estimates of gout (adjusted OR 4.65 [95% CI 3.51-6.16]). Current use of calcium channel blockers or losartan slightly attenuated the risk of gout in patients who took diuretics.

CONCLUSION

Use of loop diuretics, thiazide diuretics, and thiazide-like diuretics was associated with an increased risk of incident gout, although use of potassium-sparing agents was not.

Testosterone lab testing and initiation in the United Kingdom and the United States, 2000 to 2011

CONTEXT

New formulations, increased marketing, and wider recognition of declining testosterone levels in older age may have contributed to wider testosterone testing and supplementation in many countries.

OBJECTIVE

Our objective was to describe testosterone testing and testosterone treatment in men in the United Kingdom and United States.

DESIGN

This was a retrospective incident user cohort.

SETTING

We evaluated commercial and Medicare insurance claims from the United States and general practitioner healthcare records from the United Kingdom for the years 2000 through 2011.

PARTICIPANTS

We identified 410,019 US men and 6858 UK men who initiated a testosterone formulation as well as 1,114,329 US men and 66,140 UK men with a new testosterone laboratory measurement.

MAIN OUTCOME MEASURES

Outcome measures included initiation of any injected testosterone, implanted testosterone pellets, or prescribed transdermal or oral testosterone formulation.

RESULTS

Testosterone testing and supplementation have increased pronouncedly in the United States. Increased testing in the United Kingdom has identified more men with low levels, yet US testing has increased among men with normal levels. Men in the United States tend to initiate at normal levels more often than in the United Kingdom, and many men initiate testosterone without recent testing. Gels have become the most common initial treatment in both countries.

CONCLUSIONS

Testosterone testing and use has increased over the past decade, particularly in the United States, with dramatic shifts from injections to gels. Substantial use is seen in men without recent testing and in US men with normal levels. Given widening use despite safety and efficacy questions, prescribers must consider the medical necessity of testosterone before initiation.

Effect of ibandronate on spontaneous osteonecrosis of the knee: a randomized, double-blind, placebo-controlled trial

Based on this double-blind, placebo-controlled study, ibandronate has no beneficial effect on clinical and radiological outcome in patients with spontaneous osteonecrosis of the knee over and above anti-inflammatory medication.

INTRODUCTION

Observational studies suggest beneficial effects of bisphosphonates in spontaneous osteonecrosis (ON) of the knee. We investigated whether ibandronate would improve clinical and radiological outcome in newly diagnosed ON.

METHODS

In this randomized, double-blind, placebo-controlled trial, 30 patients (mean age, 57.3 ± 10.7 years) with ON of the knee were assigned to receive either ibandronate (cumulative dose, 13.5 mg) or placebo intravenously (divided into five doses 12 weeks). All subjects received additional treatment with oral diclofenac (70 mg) and supplementation with calcium carbonate (500 mg) and vitamin D (400 IU) to be taken daily for 12 weeks. Patients were followed for 48 weeks. The primary outcome was the change in pain score after 12 weeks. Secondary endpoints included changes in pain score, mobility, and radiological outcome (MRI) after 48 weeks.

RESULTS

At baseline, both treatment groups (IBN, n = 14; placebo, n = 16) were comparable in relation to pain score and radiological grading (bone marrow edema, ON). After 12 weeks, mean pain score was reduced in both ibandronate- (mean change, -2.98; 95% CI, -4.34 to -1.62) and placebo- (-3.59; 95% CI, -5.07 to -2.12) treated subjects (between-group comparison adjusted for age, sex, and osteonecrosis type, p = ns). Except for significant decrease in bone resorption marker (CTX) in ibandronate-treated subjects (p < 0.01), adjusted mean changes in all functional and radiological outcome measures were comparable between treatment groups after 24 and 48 weeks.

CONCLUSIONS

In patients with spontaneous osteonecrosis of the knee, bisphosphonate treatment (i.e., IV ibandronate) has no beneficial effect over and above anti-inflammatory medication.

Risk of colorectal cancer after initiation of orlistat: matched cohort study

OBJECTIVE

To examine the risk of colorectal cancer after orlistat initiation in the UK population.

DESIGN

Retrospective matched cohort study.

SETTING

Data from the UK Clinical Practice Research Datalink from September 1998 to December 2008.

PARTICIPANTS

33,625 adults aged 18 years or over who started treatment with orlistat; each orlistat initiator was matched to up to five non-initiators (n=160,347) on age, sex, body mass index, and calendar time.

MAIN OUTCOME MEASURES

Associations between orlistat initiation and the risk of colorectal cancer, assessed by calculating hazard ratios with propensity score adjusted Cox proportional hazard models.

RESULTS

Of 193,972 patients with a median age of 47 (interquartile range 37-57) years, 77% were women and approximately 90% were obese (body mass index ≥ 30). Orlistat initiators were more likely to have a previous history of diabetes or hypertension and to receive prescriptions for anti-diabetes drugs, statins, and aspirin compared with non-initiators. In the intention to treat analysis, 57 colorectal cancer events were identified among orlistat initiators and 246 among non-initiators, with median follow-up times of 2.96 and 2.86 years, respectively. The calculated incidence rate of colorectal cancer per 100,000 person years was 53 (95% confidence interval 41 to 69) for orlistat initiators and 50 (44 to 57) for non-initiators. Orlistat initiation was not associated with a higher risk of colorectal cancer (adjusted hazard ratio 1.11, 95% confidence interval 0.84 to 1.47). Findings were robust in the as treated analyses and in patients who were aged 50 years or over, were morbidly obese, or had a history of diabetes.

CONCLUSIONS

This study found no evidence of an increased risk of colorectal cancer after the initiation of orlistat. It is limited by the relatively short follow-up time, and the possibility of adverse effects of long term orlistat use on risk of colorectal cancer cannot be excluded.

Case-control analysis on metformin and cancer of the esophagus

PURPOSE

Metformin use has been associated with decreased cancer risks, though data on esophageal cancer are scarce. We explored the relation between use of metformin or other anti-diabetic drugs and the risk of esophageal cancer.

METHODS

We conducted a case-control analysis in the UK-based general practice research database (GPRD, now clinical practice research datalink, CPRD). Cases were individuals with an incident diagnosis of esophageal cancer between 1994 and 2010 at age 40-89 years. Ten controls per case were matched on age, sex, calendar time, general practice, and number of years of active history in the GPRD prior to the index date. Various potential confounders including diabetes mellitus, gastro-esophageal reflux, and use of proton-pump inhibitors were evaluated in univariate models, and the final results were adjusted for BMI and smoking. Results are presented as odds ratios (ORs) with 95 % confidence intervals (CI).

RESULTS

Long-term use (≥30 prescriptions) of metformin was not associated with a materially altered risk of esophageal cancer (adj. OR 1.23, 95 % CI 0.92-1.65), nor was long-term use of sulfonylureas (adj. OR 0.93, 95 % CI 0.70-1.23), insulin (adj. OR 0.87, 95 % CI 0.60-1.25), or of thiazolidinediones (adj. OR 0.71, 95 % CI 0.37-1.36).

CONCLUSION

In our population-based study, use of metformin was not associated with an altered risk of esophageal cancer.

Drug-/radiation-induced interstitial lung disease in the United Kingdom general population: incidence, all-cause mortality and characteristics at diagnosis

BACKGROUND AND OBJECTIVE

Radiotherapy and an increasing number of substances are implicated in the pathogenesis of interstitial lung disease (ILD). While the frequency of published data on more common ILD entities such as the idiopathic interstitial pneumonias has increased in recent years, less attention has been given to relatively rarely occurring forms such as drug-/radiation-induced ILD.

METHODS

Data from the UK-based General Practice Research Database (GPRD) was used to estimate the incidence of drug-/radiation-induced ILD over a 12-year period (1997-2008). Crude incidence rates were stratified by gender, age group and calendar period, and rate ratios were adjusted using Poisson regression. All-cause mortality was modelled using Cox regression, and characteristics at diagnosis were compared with a random sample of matched, non-ILD controls using conditional logistic regression.

RESULTS

A total of 128 patients with an incident diagnosis of drug-/radiation-induced ILD were identified, and the overall incidence density during the study period was 4.1 (95% confidence interval 3.4-4.9) per million person-years. Incidence rates increased during the time period 1997-2005 and decreased thereafter. The adjusted all-cause mortality was >4 times higher in cases compared with controls.

CONCLUSIONS

This UK population-based study characterizes patients diagnosed with drug-/radiation-induced ILD and quantifies incidence and all-cause mortality during 1997-2008. No statistically significant time trend in incidence was found, despite having observed numeric increases in incidence rates during the study window. Future research using the GPRD and other data sources is required to better understand the disposition of patients diagnosed with drug-/radiation-induced ILD and to investigate potential trends incidence and mortality over time.

Seizures in patients with Alzheimer's disease or vascular dementia: a population-based nested case-control analysis

PURPOSE

Patients with Alzheimer's disease (AD) have an increased risk of developing seizures or epilepsy. Little is known about the role of risk factors and about the risk of developing seizures/epilepsy in patients with vascular dementia (VD). The aim of this study was to assess incidence rates (IRs) of seizures/epilepsy in patients with AD, VD, or without dementia, and to identify potential risk factors of seizures or epilepsy.

METHODS

We conducted a follow-up study with a nested case-control analysis using the United Kingdom-based General Practice Research Database (GPRD). We identified patients aged ≥65 years with an incident diagnosis of AD or VD between 1998 and 2008 and a matched comparison group of dementia-free patients. Conditional logistic regression was used to estimate the odds ratio (OR) with a 95% confidence interval (CI) of developing seizures/epilepsy in patients with AD or VD, stratified by age at onset and duration of dementia as well as by use of antidementia drugs.

KEY FINDINGS

Among 7,086 cases with AD, 4,438 with VD, and 11,524 matched dementia-free patients, we identified 180 cases with an incident diagnosis of seizures/epilepsy. The IRs of epilepsy/seizures for patients with AD or VD were 5.6/1,000 person-years (py) (95% CI 4.6-6.9) and 7.5/1,000 py (95% CI 5.7-9.7), respectively, and 0.8/1,000 py (95% CI 0.6-1.1) in the dementia-free group. In the nested case-control analysis, patients with longer standing (≥3 years) AD had a slightly higher risk of developing seizures or epilepsy than those with a shorter disease duration, whereas in patients with VD the contrary was observed.

SIGNIFICANCE

Seizures or epilepsy were substantially more common in patients with AD and VD than in dementia-free patients. The role of disease duration as a risk factor for seizures/epilepsy seems to differ between AD and VD.

Metformin does not alter the risk of lung cancer: a case-control analysis

BACKGROUND

Metformin use has been linked to a decreased cancer risk. We explored the association between use of metformin or other antidiabetic drugs and the risk of lung cancer.

METHODS

We assessed the association between metformin, and other antidiabetic drugs and lung cancer using a case-control analysis in the UK-based General Practice Research Database (GPRD). Cases were people with an incident diagnosis of lung cancer. Up to 6 controls per case were matched on age, sex, calendar time, general practice, and number of years of active history in the GPRD. The contribution of potential confounders including tuberculosis, chronic obstructive pulmonary disease (COPD), diabetes mellitus, and co-morbid conditions to diabetes was evaluated in univariate models, and final results were adjusted for BMI and smoking.

RESULTS

Long-term use (≥40 prescriptions) of metformin was not associated with an altered risk of lung cancer (adj. OR 1.21, 95% CI 0.97-1.50. Long-term use of sulfonylureas was linked to a marginally decreased risk of lung cancer (adj. OR 0.74, 95% CI 0.60-0.90. This risk decrease was observed in men (adj. OR 0.64, 95% CI 0.50-0.83) but not in women (adj. OR 0.97, 95% CI 0.69-1.37) and this risk decrease was not statistically significant in an analysis restricted to diabetic patients only (adj. OR. 0.82, 95% CI 0.65-1.02). Long-term use of insulin was associated with a slightly increased risk of lung cancer (adj. OR 1.33, 95% CI 1.04-1.71); however, no consistent trend across duration strata was observed.

CONCLUSION

Metformin did not decrease the risk of lung cancer.