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In recent years regression discontinuity designs have been used increasingly for the estimation of treatment effects in observational medical data where a rule-based decision to apply treatment is taken using a continuous assignment variable. Most regression discontinuity design applications have focused on effect estimation where the outcome of interest is continuous, with scenarios with binary outcomes receiving less attention, despite their ubiquity in medical studies. In this work, we develop an approach to estimation of the risk ratio in a fuzzy regression discontinuity design (where treatment is not always strictly applied according to the decision rule), derived using common regression discontinuity design assumptions. This method compares favourably to other risk ratio estimation approaches: the established Wald estimator and a risk ratio estimate from a multiplicative structural mean model, with promising results from extensive simulation studies. A demonstration and further comparison are made using a real example to evaluate the effect of statins (where a statin prescription is made based on a patient's 10-year cardiovascular disease risk score) on low-density lipoprotein cholesterol reduction in UK Primary Care. [ABSTRACT FROM AUTHOR]

Regression discontinuity designs (RDDs) have been developed for the estimation of treatment effects using observational data, where a treatment is administered using an externally defined decision rule, linked to a continuous assignment variable. Typically, RDDs have been applied to situations where the outcome of interest is continuous and non‐temporal. Conversely, RDDs for time‐to‐event outcomes have received less attention, despite such outcomes being common in many applications. We explore RDDs for a time‐to‐event outcome subject to right censoring. An accelerated failure time (AFT) approach is used to establish a treatment effect estimate for a fuzzy RDD (where treatment is not always strictly applied according to the decision rule). This estimation approach is robust to different levels of fuzziness and unobserved confounding, assessed using simulation studies and compares favourably to established structural AFT models. A motivating example is presented in which models are fitted to estimate the effect of metformin on mortality and cardiovascular disease rate using real observational data from UK Primary Care. [ABSTRACT FROM AUTHOR]

Background: We aimed to estimate the clinical effectiveness of Community Occupational Therapy for people with dementia and family carers-UK version (Community Occupational Therapy in Dementia-UK version [COTiD-UK]) relative to treatment as usual (TAU). We hypothesised that COTiD-UK would improve the ability of people with dementia to perform activities of daily living (ADL), and family carers' sense of competence, compared with TAU.Methods and Findings: The study design was a multicentre, 2-arm, parallel-group, assessor-masked, individually randomised controlled trial (RCT) with internal pilot. It was conducted in 15 sites across England from September 2014 to January 2018. People with a diagnosis of mild to moderate dementia living in their own home were recruited in pairs with a family carer who provided domestic or personal support for at least 4 hours per week. Pairs were randomised to either receive COTiD-UK, which comprised 10 hours of occupational therapy delivered over 10 weeks in the person with dementia's home or TAU, which comprised the usual local service provision that may or may not include standard occupational therapy. The primary outcome was the Bristol Activities of Daily Living Scale (BADLS) score at 26 weeks. Secondary outcomes for the person with dementia included the following: the BADLS scores at 52 and 78 weeks, cognition, quality of life, and mood; and for the family carer: sense of competence and mood; plus the number of social contacts and leisure activities for both partners. Participants were analysed by treatment allocated. A total of 468 pairs were recruited: people with dementia ranged from 55 to 97 years with a mean age of 78.6 and family carers ranged from 29 to 94 with a mean of 69.1 years. Of the people with dementia, 74.8% were married and 19.2% lived alone. Of the family carers, 72.6% were spouses, and 22.2% were adult children. On randomisation, 249 pairs were assigned to COTiD-UK (62% people with dementia and 23% carers were male) and 219 to TAU (52% people with dementia and 32% carers were male). At the 26 weeks follow-up, data were available for 364 pairs (77.8%). The BADLS score at 26 weeks did not differ significantly between groups (adjusted mean difference estimate 0.35, 95% CI -0.81 to 1.51; p = 0.55). Secondary outcomes did not differ between the groups. In total, 91% of the activity-based goals set by the pairs taking part in the COTiD-UK intervention were fully or partially achieved by the final COTiD-UK session. Study limitations include the following: Intervention fidelity was moderate but varied across and within sites, and the reliance on primarily proxy data focused on measuring the level of functional or cognitive impairment which may not truly reflect the actual performance and views of the person living with dementia.Conclusions: Providing community occupational therapy as delivered in this study did not improve ADL performance, cognition, quality of life, or mood in people with dementia nor sense of competence or mood in family carers. Future research should consider measuring person-centred outcomes that are more meaningful and closely aligned to participants' priorities, such as goal achievement or the quantity and quality of activity engagement and participation.Trial Registration: Current Controlled Trials ISRCTN10748953. [ABSTRACT FROM AUTHOR]

Background: Statins are widely prescribed for the primary prevention of cardiovascular disease. Guidelines exist for statin prescriptions, but there is little recent analysis concerning prescription trends over time and how these vary with respect to demographic variables. Methods and results: Using The Health Improvement Network primary care database, statin therapy initiation and statin prescription prevalence rates were calculated using data from 7,027,711 individuals across the UK for the years 1995 to 2013, overall and stratified by sex, age group, and socioeconomic deprivation level (Townsend score). Statin therapy initiation rates rose sharply from 1995 (0.51 per 1,000 person-years) up to 2006 (19.83 per 1,000 person-years) and thereafter declined (10.76 per 1,000 person-years in 2013). Males had higher initiation rates than females and individuals aged 60-85 years had higher initiation rates than younger or more elderly age groups. Initiation rates were slightly higher as social deprivation level increased, after accounting for age and sex. Prescription prevalence increased sharply from 1995 (2.36 per 1,000 person-years) to 2013 (128.03 per 1,000 person-years) with males generally having a higher prevalence rate, over time, than females. Prevalence rates over time were generally higher for older age groups but were similar with respect to social deprivation level. Conclusion: The uptake of statins within UK primary care has increased greatly over time with statins being more commonly prescribed to older patients in general and, in recent years, males appear to have been prescribed statins at higher rates than females. After accounting for age and sex, the statin therapy initiation rate increases with the level of social deprivation. [ABSTRACT FROM AUTHOR]

Objective To examine the frequency and characteristics of headaches and their association with global disease activity and health-related quality of life (HRQOL) in patients with systemic lupus erythematosus (SLE). Methods A disease inception cohort was assessed annually for headache (5 types) and 18 other neuropsychiatric (NP) events. Global disease activity scores (SLE Disease Activity Index 2000 [SLEDAI-2K]), damage scores (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index [SDI]), and Short Form 36 (SF-36) mental and physical component summary scores were collected. Time to first headache and associations with SF-36 scores were analyzed using Cox proportional hazards and linear regression models with generalized estimating equations. Results Among the 1,732 SLE patients enrolled, 89.3% were female and 48.3% were white. The mean ± SD age was 34.6 ± 13.4 years, duration of disease was 5.6 ± 5.2 months, and length of followup was 3.8 ± 3.1 years. At enrollment, 17.8% of patients had headache (migraine [60.7%], tension [38.6%], intractable nonspecific [7.1%], cluster [2.6%], and intracranial hypertension [1.0%]). The prevalence of headache increased to 58% after 10 years. Only 1.5% of patients had lupus headache, as identified in the SLEDAI-2K. In addition, headache was associated with other NP events attributed to either SLE or non-SLE causes. There was no association of headache with SLEDAI-2K scores (without the lupus headache variable), SDI scores, use of corticosteroids, use of antimalarials, use of immunosuppressive medications, or specific autoantibodies. SF-36 mental component scores were lower in patients with headache compared with those without headache (mean ± SD 42.5 ± 12.2 versus 47.8 ± 11.3; P < 0.001), and similar differences in physical component scores were seen (38.0 ± 11.0 in those with headache versus 42.6 ± 11.4 in those without headache; P < 0.001). In 56.1% of patients, the headaches resolved over followup. Conclusion Headache is frequent in SLE, but overall, it is not associated with global disease activity or specific autoantibodies. Although headaches are associated with a lower HRQOL, the majority of headaches resolve over time, independent of lupus-specific therapies. [ABSTRACT FROM AUTHOR]

Objective. MTX is widely used to treat synovitis in PsA without supporting trial evidence. The aim of our study was to test the value of MTX in the first large randomized placebo-controlled trial (RCT) in PsA.Methods. A 6-month double-blind RCT compared MTX (15 mg/week) with placebo in active PsA. The primary outcome was PsA response criteria (PsARC). Other outcomes included ACR20, DAS-28 and their individual components. Missing data were imputed using multiple imputation methods. Treatments were compared using logistic regression analysis (adjusted for age, sex, disease duration and, where appropriate, individual baseline scores).Results. Four hundred and sixty-two patients were screened and 221 recruited. One hundred and nine patients received MTX and 112 received placebo. Forty-four patients were lost to follow-up (21 MTX, 23 placebo). Twenty-six patients discontinued treatment (14 MTX, 12 placebo). Comparing MTX with placebo in all randomized patients at 6 months showed no significant effect on PsARC [odds ratio (OR) 1.77, 95% CI 0.97, 3.23], ACR20 (OR 2.00, 95% CI 0.65, 6.22) or DAS-28 (OR 1.70, 95% CI 0.90, 3.17). There were also no significant treatment effects on tender and swollen joint counts, ESR, CRP, HAQ and pain. The only benefits of MTX were reductions in patient and assessor global scores and skin scores at 6 months (P = 0.03, P < 0.001 and P = 0.02, respectively). There were no unexpected adverse events.Conclusions. This trial of active PsA found no evidence for MTX improving synovitis and consequently raises questions about its classification as a disease-modifying drug in PsA.Trial registration. Current Controlled Trials, www.controlled-trials.com, ISRCTN:54376151. [ABSTRACT FROM AUTHOR]

Objective: To calculate the chance of a seizure in the next year (COSY) for seizures with impaired awareness in those experiencing auras only, those with no seizures and those with continuing seizures. Epilepsy surgery is an effective treatment for refractory focal epilepsy. Driving is an important factor affecting quality of life. In the UK, driving is not permitted if focal seizures with no impairment of awareness (auras, simple partial seizures) continue, if there is a prior history of seizures with impaired awareness, as will invariably be the case in those having epilepsy surgery. Current UK driving regulations allow driving if COSY is less than 20%., Method: We calculated COSY in 819 epilepsy surgery patients with up to 25 years follow-up. Each patient year was graded on the The International League against Epilepsy surgery outcome scale., Results: Patients who were entirely seizure-free for 1, 2 and 3 years had COSY of 4.9%, 3.5% and 2.4% respectively. Patients with only auras within the last 1, 2 or 3 years had a COSY of 11.3%, 9.2% and 7.8% respectively., Conclusions: Individuals with auras only after epilepsy surgery had a higher COSY than those who were seizure-free. If a COSY of below 20% is regarded as an acceptable risk, it may be suggested that those with auras only in a given year be allowed to drive. The relative risk of these patients causing accidents is lower than population groups such as those aged <25 or >75 years, who are permitted to drive., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)