Diana Battistutta

Daily sunscreen application and betacarotene supplementation in prevention of basal-cell and squamous-cell carcinomas of the skin: a randomised controlled trial

BACKGROUND The use of sunscreens on the skin can prevent sunburn but whether long-term use can prevent skin cancer is not known. Also, there is evidence that oral betacarotene supplementation lowers skin-cancer rates in animals, but there is limited evidence of its effect in human beings. METHODS In a community-based randomised trial with a 2 by 2 factorial design, individuals were assigned to four treatment groups: daily application of a sun protection factor 15-plus sunscreen to the head, neck, arms, and hands, and betacarotene supplementation (30 mg per day); sunscreen plus placebo tablets; betacarotene only; or placebo only. Participants were 1621 residents of Nambour in southeast Queensland, Australia. The endpoints after 4.5 years of follow-up were the incidence of basal-cell and squamous-cell carcinomas both in terms of people treated for newly diagnosed disease and in terms of the numbers of tumours that occurred. Analysis of the effect of sunscreen was based only on skin cancers that developed on sites of daily application. All analyses were by intention to treat. FINDINGS 1383 participants underwent full skin examination by a dermatologist in the follow-up period. 250 of them developed 758 new skin cancers during the follow-up period. There were no significant differences in the incidence of first new skin cancers between groups randomly assigned daily sunscreen and no daily sunscreen (basal-cell carcinoma 2588 vs 2509 per 100,000; rate ratio 1.03 [95% CI 0.73-1.46]; squamous-cell carcinoma 876 vs 996 per 100,000; rate ratio 0.88 [0.50-1.56]). Similarly, there was no significant difference between the betacarotene and placebo groups in incidence of either cancer (basal-cell carcinoma 3954 vs 3806 per 100,000; 1.04 [0.73-1.27]; squamous-cell carcinoma 1508 vs 1146 per 100,000; 1.35 [0.84-2.19]). In terms of the number of tumours, there was no effect on incidence of basal-cell carcinoma by sunscreen use or by betacarotene but the incidence of squamous-cell carcinoma was significantly lower in the sunscreen group than in the no daily sunscreen group (1115 vs 1832 per 100,000; 0.61 [0.46-0.81]). INTERPRETATION There was no harmful effect of daily use of sunscreen in this medium-term study. Cutaneous squamous-cell carcinoma, but not basal-cell carcinoma seems to be amenable to prevention through the routine use of sunscreen by adults for 4.5 years. There was no beneficial or harmful effect on the rates of either type of skin cancer, as a result of betacarotene supplementation.

Lymphedema After Breast Cancer: Incidence, Risk Factors, and Effect on Upper Body Function

PURPOSE Secondary lymphedema is associated with adverse physical and psychosocial consequences among women with breast cancer (BC). This article describes the prevalence and incidence of lymphedema between 6 and 18 months after BC treatment; personal, treatment, and behavioral correlates of lymphedema status; and the presence of other upper-body symptoms (UBS) and function (UBF). PATIENTS AND METHODS A population-based sample of Australian women (n = 287) with recently diagnosed, invasive BC were evaluated on five occasions using bioimpedance spectroscopy. Lymphedema was diagnosed when the ratio of impedance values, comparing treated and untreated sides, was three standard deviations more than normative data. UBF was assessed using the validated Disability of the Arm, Shoulder, and Hand questionnaire. RESULTS From 6 to 18 months after surgery, 33% (n = 62) of the sample were classified as having lymphedema; of these, 40% had long-term lymphedema. Although older age, more extensive surgery or axillary node dissection, and experiencing one or more treatment-related complication(s) or symptom(s) at baseline were associated with increased odds, lower socioeconomic status, having a partner, greater child care responsibilities, being treated on the dominant side, participation in regular activity, and having good UBF were associated with decreased odds of lymphedema. Not surprisingly, lymphedema leads to reduced UBF; however, BC survivors report high prevalences of other UBS (34% to 62%), irrespective of their lymphedema status. CONCLUSION Lymphedema is a public health issue deserving greater attention. More systematic surveillance for earlier detection and the potential benefits of physical activity to prevent lymphedema and mitigate symptoms warrant further clinical integration and research.

Lymphedema after gynecological cancer treatment - prevalence, correlates, and supportive care needs

Few studies have evaluated lymphedema after gynecological cancer treatment. The aim of this research was to establish prevalence, correlates, and supportive care needs of gynecological cancer survivors who develop lymphedema.

Risk Analysis in the Development of Pterygia

PURPOSE No detailed analysis of risk factors in the development of pterygia has been previously performed. In this report, the authors identify and quantify these risk factors. METHODS In a case-control study, 278 patients treated in a Brisbane hospital for primary pterygium between 1973 and 1978 were compared with a similar number of people without pterygium who were matched for age, race, and sex, using information from a standard questionnaire completed during a personal interview. RESULTS Risk of pterygium was increased among patients who, in their third decade of life, worked outdoors in an environment with high surface reflectance of ultraviolet light compared with those who worked indoors. The elevation of risk was raised several hundred-fold among those subjects who worked mainly on sand compared with those who worked indoors when results were adjusted for associated risk factors. When risk was measured among subjects who worked in an environment that was mainly concrete, risk was increased almost 20-fold. Those subjects who spent their first 5 years of life at latitudes less than 30 degrees had almost 40 times the risk of pterygium than those living at latitudes greater than 40 degrees; spending the majority of times outdoors in these earliest years was associated with a 20-fold increase in risk of developing pterygium. There was a strong protective element in the wearing of regular glasses, sunglasses, or a hat. CONCLUSIONS There is a strong suggestion of a causal relationship between ultraviolet light exposure and the development of pterygia during the early years of life and the cumulative exposure over the next 2 to 3 decades in occupations in which there is a high component of reflected ultraviolet light.

EFFECTIVENESS OF BICYCLE HELMETS IN PREVENTING HEAD INJURY IN CHILDREN: CASE-CONTROL STUDY

Abstract Objective : To examine the risk of injury to the head and the effect of wearing helmets in bicycle accidents among children. Design : Case-control study by questionnaire completed by the children and their carers. Setting : Two large childrens hospitals in Brisbane, Australia. Subjects : 445 children presenting with bicycle related injuries during 15 April 1991 to 30 June 1992. The cases comprised 102 children who had sustained injury to the upper head including the skull, forehead and scalp or loss of consciousness. The controls were 278 cyclists presenting with injuries other than to the head or face. A further 65 children with injuries to the face were considered as an extra comparison group. Main outcome measures : Cause and type of injury, wearing of helmet. Results : Most children (230) were injured after losing control and falling from their bicycle. Only 31 had contact with another moving vehicle. Children with head injury were significantly more likely to have made contact with a moving vehicle than control children (19 (19%) v 12 (4%), P<0.001). Head injuries were more likely to occur on paved surfaces than on grass, gravel, or dirt. Wearing a helmet reduced the risk of head injury by 63% (95% confidence interval 34% to 80%) and of loss of consciousness by 86% (62% to 95%). Conclusions : The risk of head injury in bicycle accidents is reduced among children wearing a helmet. Current helmet design maximises protection in the type of accident most commonly occurring in this study. Legislation enforcing helmet use among children should be considered.

Codon usage in Plasmodium falciparum.

The codon frequencies used in 7874 codons from 17 sequences of Plasmodium falciparum have been examined. The frequency distribution is markedly biased. A and C occur with similar frequency in all positions but G is predominantly in the first base and T is predominantly in the last position. This information can be used to predict the coding strand and reading frame of P. falciparum genes.

A systematic review comparing the relative effectiveness of antimicrobial-coated catheters in intensive care units

BACKGROUND Bloodstream infection related to a central venous catheter is a substantial clinical and economic problem. To develop policy for managing the risks of these infections, all available evidence for prevention strategies should be synthesized and understood. METHODS We evaluate evidence (1985-2006) for short-term antimicrobial-coated central venous catheters in lowering rates of catheter-related bloodstream infection (CRBSI) in the adult intensive care unit. Evidence was appraised for inclusion against predefined criteria. Data extraction was by 2 independent reviewers. Thirty-four studies were included in the review. Antiseptic, antibiotic, and heparin-coated catheters were compared with uncoated catheters and one another. Metaanalysis was used to generate summary relative risks for CRBSI and catheter colonization by antimicrobial coating. RESULTS Externally impregnated chlorhexidine/silver sulfadiazine catheters reduce risk of CRBSI relative to uncoated catheters (RR, 0.66; 95% CI: 0.47-0.93). Minocycline and rifampicin-coated catheters are significantly more effective relative to CHG/SSD catheters (RR, 0.12; 95% CI: 0.02-0.67). The new generation chlorhexidine/silver sulfadiazine catheters and silver, platinum, and carbon-coated catheters showed nonsignificant reductions in risk of CRBSI compared with uncoated catheters. CONCLUSION Two decades of evidence describe the effectiveness of antimicrobial catheters in preventing CRBSI and provide useful information about which catheters are most effective. Questions surrounding their routine use will require supplementation of this trial evidence with information from more diverse sources.

Determinants of rapid weight gain during infancy: baseline results from the NOURISH randomised controlled trial

BackgroundRapid weight gain in infancy is an important predictor of obesity in later childhood. Our aim was to determine which modifiable variables are associated with rapid weight gain in early life.MethodsSubjects were healthy infants enrolled in NOURISH, a randomised, controlled trial evaluating an intervention to promote positive early feeding practices. This analysis used the birth and baseline data for NOURISH. Birthweight was collected from hospital records and infants were also weighed at baseline assessment when they were aged 4-7 months and before randomisation. Infant feeding practices and demographic variables were collected from the mother using a self administered questionnaire. Rapid weight gain was defined as an increase in weight-for-age Z-score (using WHO standards) above 0.67 SD from birth to baseline assessment, which is interpreted clinically as crossing centile lines on a growth chart. Variables associated with rapid weight gain were evaluated using a multivariable logistic regression model.ResultsComplete data were available for 612 infants (88% of the total sample recruited) with a mean (SD) age of 4.3 (1.0) months at baseline assessment. After adjusting for mothers age, smoking in pregnancy, BMI, and education and infant birthweight, age, gender and introduction of solid foods, the only two modifiable factors associated with rapid weight gain to attain statistical significance were formula feeding [OR = 1.72 (95%CI 1.01-2.94), P = 0.047] and feeding on schedule [OR = 2.29 (95%CI 1.14-4.61), P = 0.020]. Male gender and lower birthweight were non-modifiable factors associated with rapid weight gain.ConclusionsThis analysis supports the contention that there is an association between formula feeding, feeding to schedule and weight gain in the first months of life. Mechanisms may include the actual content of formula milk (e.g. higher protein intake) or differences in feeding styles, such as feeding to schedule, which increase the risk of overfeeding.Trial RegistrationAustralian Clinical Trials Registry ACTRN12608000056392

The nambour skin cancer and actinic eye disease prevention trial: Design and baseline characteristics of participants

The Nambour Skin Cancer and Actinic Eye Disease Prevention Trial (the Nambour Trial) is a field trial conducted in an unselected adult population in Australia. Using a randomized 2 x 2 factorial design, the principal aim is to evaluate whether regular use of high-protection sunscreen and/or dietary supplementation with beta-carotene (30 mg daily) can alter the incidence rates of basal cell carcinomas and squamous cell carcinomas of the skin over a minimum follow-up time of 4.5 years. Changes in the incidence of solar keratoses and actinic eye disease and the rate of photoaging after intervention will also be investigated. In 1992, 1626 participants between the ages of 25 and 75 years were enrolled, all of whom had been randomly selected from residents of the southeastern Queensland township of Nambour for an earlier skin cancer prevalence survey. This paper describes the background to the trial and its design, with respect to evaluation of effects on actinic skin disease, and documents the baseline characteristics of participants recruited into the Nambour Trial.

A comparison of gait initiation and termination methods for obtaining plantar foot pressures.

The midgait protocol is the most commonly used method to collect pressure platform data. Spatial limitations, however, frequently render this technique unsuitable. Alternative gait protocols have focused on gait initiation procedures in obtaining data. The current study investigated whether a commonly cited two-step gait initiation protocol, or a two-step gait termination protocol produced pressure data more representative of the criterion, midgait method. A pressure platform was used to collect data for 25 asymptomatic subjects using the midgait, two-step gait initiation and two-step gait termination walking protocols. The contact duration, percentage contact duration, peak pressure, peak force, pressure-time integral and force-time integral were calculated for seven sites within the foot. Multivariate analysis of variance with repeated measures identified significant protocol by site interactions for all variables except the force-time integral. The gait initiation protocol, although having minimal effect on peak pressures beneath the forefoot, markedly altered the relative timing parameters of the foot. In contrast, the gait termination protocol had minimal effect on temporal parameters, but resulted in a reduction in pressures beneath the forefoot. Abbreviated gait protocols are often employed in plantar pressure studies. This study suggests that the choice between a gait initiation and termination protocol is largely dependent on the gait parameter of interest.