Relationship of weight and obesity with the risk of knee and hip arthroplasty for osteoarthritis across different levels of physical performance: a prospective cohort study.

OBJECTIVE: To examine the association between obesity and knee and hip arthroplasty for osteoarthritis across a range of physical performance. METHOD: The body mass index and physical performance (on the 36-item Short Form Health Survey) of 9135 Australian Diabetes, Obesity and Lifestyle Study participants were measured in 1999-2000. The incidence of knee and hip arthroplasty during 2002-2011 was determined by linking the cohort records to the Australian Orthopaedic Association National Joint Replacement Registry. RESULTS: Over 9.1 ± 2.3 years (mean ± sd)) of follow-up, 317 participants had knee and 202 had hip arthroplasty for osteoarthritis. Using those with neither obesity nor significantly impaired physical performance as the reference group, participants with both obesity and significantly impaired physical performance had a higher knee arthroplasty risk [hazard ratio (HR) = 5.25, 95% confidence interval (CI) 3.85-7.14] than those with obesity alone (HR = 2.49, 95% CI 1.81-3.44) or impaired physical performance alone (HR = 2.19, 95% CI 1.59-3.02). Similar results were observed for hip arthroplasty (obesity and impaired physical performance: HR = 2.67, 95% CI 1.72-4.15; obesity alone: HR = 1.65, 95% CI 1.08-2.51; impaired physical performance alone: HR = 1.83, 95% CI 1.26-2.66). Among overweight/obese patients, 5 kg greater baseline weight increased the knee arthroplasty risk across all levels of physical performance, and hip arthroplasty risk in those with the highest level of physical performance. CONCLUSION: Although impaired physical performance is an independent risk factor for knee and hip arthroplasty, greater weight increased knee arthroplasty for overweight/obese participants at all levels of physical performance, but hip arthroplasty only in those with good physical performance. Targeting weight loss has the potential to reduce the risk of knee arthroplasty and improve patient outcomes, even in those with poor physical performance.

Risk factors for infectiousness of patients with tuberculosis: a systematic review and meta-analysis.

We performed a systematic review and meta-analyses of studies assessing tuberculosis (TB) patient-related risk factors for transmission of Mycobacterium tuberculosis infection. Meta-analyses were conducted for sputum smear-positivity, lung cavitation and HIV seropositivity of index patients with both crude and adjusted odds ratios (AORs) pooled using random effect models. Thirty-seven studies were included in the review. We found that demographic characteristics such as age and sex were not significant risk factors, while behaviours such as smoking and alcohol intake were associated with infectiousness although inconsistently. Treatment delay of >28 days was a significant predictor of greater infectiousness. Contacts of sputum smear-positive index patients were found to be more likely to be infected than contacts of sputum smear-negative patients, with a pooled AOR of 2.15 (95% confidence interval (CI) 1.47-3.17, I 2 = 38%). Similarly, contacts of patients with the cavitary disease were around twice as likely to be infected as contacts of patients without cavitation (pooled AOR 1.9, 95% CI 1.26-2.84, I 2 = 63%). In contrast, HIV seropositive patients were associated with few contact infections than HIV seronegative patients (AOR 0.45, 95% CI 0.26-0.80, I 2 = 52%). In conclusion, behavioural and clinical characteristics of TB patients can be used to identify highly infectious patients for targeted interventions.

Mathematical Modelling of Trachoma Transmission, Control and Elimination.

The World Health Organization has targeted the elimination of blinding trachoma by the year 2020. To this end, the Global Elimination of Blinding Trachoma (GET, 2020) alliance relies on a four-pronged approach, known as the SAFE strategy (S for trichiasis surgery; A for antibiotic treatment; F for facial cleanliness and E for environmental improvement). Well-constructed and parameterized mathematical models provide useful tools that can be used in policy making and forecasting in order to help to control trachoma and understand the feasibility of this large-scale elimination effort. As we approach this goal, the need to understand the transmission dynamics of infection within areas of different endemicities, to optimize available resources and to identify which strategies are the most cost-effective becomes more pressing. In this study, we conducted a review of the modelling literature for trachoma and identified 23 articles that included a mechanistic or statistical model of the transmission, dynamics and/or control of (ocular) Chlamydia trachomatis. Insights into the dynamics of trachoma transmission have been generated through both deterministic and stochastic models. A large body of the modelling work conducted to date has shown that, to varying degrees of effectiveness, antibiotic administration can reduce or interrupt trachoma transmission. However, very little analysis has been conducted to consider the effect of nonpharmaceutical interventions (and particularly the F and E components of the SAFE strategy) in helping to reduce transmission. Furthermore, very few of the models identified in the literature review included a structure that permitted tracking of the prevalence of active disease (in the absence of active infection) and the subsequent progression to disease sequelae (the morbidity associated with trachoma and ultimately the target of GET 2020 goals). This represents a critical gap in the current trachoma modelling literature, which makes it difficult to reliably link infection and disease. In addition, it hinders the application of modelling to assist the public health community in understanding whether trachoma programmes are on track to reach the GET goals by 2020. Another gap identified in this review was that of the 23 articles examined, only one considered the cost-effectiveness of the interventions implemented. We conclude that although good progress has been made towards the development of modelling frameworks for trachoma transmission, key components of disease sequelae representation and economic evaluation of interventions are currently missing from the available literature. We recommend that rapid advances in these areas should be urgently made to ensure that mathematical models for trachoma transmission can robustly guide elimination efforts and quantify progress towards GET 2020.

Moisturizers: The Slippery Road.

Moisturizers are an important part of a dermatologist's armamentarium although little is written and well, a less is truly known about them. There is a cornucopia of projected skin products in the market whose real scientific role is not proven. These products although at times are regarded as mere cosmetics but have a well-known role in many skin disorders. Adequate knowledge about their mechanism of action, dosage, usage, and adverse effects is must for a dermatologist in this era. This article aims to bring forth the ever hidden facts of the much-hyped moisturizers. It is probably the first of its kind covering all aspects of moisturizers ranging from basic science to clinical usage, a subject that receives a short shrift in the current dermatological text.

Antinociceptive activity of a neurosteroid tetrahydrodeoxycorticosterone (5alpha-pregnan-3alpha-21-diol-20-one) and its possible mechanism(s) of action.

The present study investigates the effects of a neurosteroid tetrahydrodeoxycorticosterone (5alpha-pregnan-3alpha-21-diol-20-one) in two experimental models of pain sensitivity in mice. Tetrahydrodeoxycorticosterone (2.5, 5 mg/kg, i.p.) dose dependently decreased the licking response in formalin test and increased the tail flick latency (TFL) in tail flick test. Bicuculline (2 mg/kg, i.p.), a GABA(A) receptor antagonist blocked the antinociceptive effect of tetrahydrodeoxycorticosterone in TFL test but failed to modulate licking response in formalin test. Naloxone (1 mg/kg, i.p.), an opioid antagonist effectively attenuated the analgesic effect of tetrahydrodeoxycorticosterone in both the models. Tetrahydrodeoxycorticosterone pretreatment potentiated the antinociceptive response of morphine, an opioid compound and nimodipine, a calcium channel blocker in formalin as well as TFL test. Thus, tetrahydrodeoxycorticosterone exerts an analgesic effect, which may be mediated by modulating GABA-ergic and/or opioid-ergic mechanisms and voltage-gated calcium channels.

Imaging appearances of meningeal melanocytoma.

Meningeal melanocytoma is an uncommon, benign melanocytic tumour of the meninges. Only 15 cases have been reported to date. We present the MR and CT appearance of a case of compressive myelopathy due to cervical meningeal melanocytoma. Careful analysis of the imaging features, as illustrated in the present case, allows a preoperative diagnosis. The differential diagnosis includes malignant melanoma and melanocytic meningioma.