Sharon L. Brennan

Incidence and risk factors for deep surgical site infection after primary total hip arthroplasty : a systematic review

Although deep surgical site infection (SSI) is a major complication of primary total hip arthroplasty (THA), there are conflicting data regarding the incidence of deep SSI, and no comprehensive evaluation of the associated risk factors has been undertaken. We performed a systematic review of the literature; undertaking computer-aided searches of electronic databases, assessment of methodological quality, and a best-evidence synthesis. The incidence of SSI ranged from 0.2% before discharge to 1.1% for the period up to and including 5 years post surgery. Greater severity of a pre-existing illness and a longer duration of surgery were found to be independent risk factors for deep SSI. There is a need for high-quality, prospective studies to further identify modifiable risk factors for deep SSI after THA.

Relationship between diet and mental health in children and adolescents: a systematic review.

We systematically reviewed 12 epidemiological studies to determine whether an association exists between diet quality and patterns and mental health in children and adolescents; 9 explored the relationship using diet as the exposure, and 3 used mental health as the exposure. We found evidence of a significant, cross-sectional relationship between unhealthy dietary patterns and poorer mental health in children and adolescents. We observed a consistent trend for the relationship between good-quality diet and better mental health and some evidence for the reverse. When including only the 7 studies deemed to be of high methodological quality, all but 1 of these trends remained. Findings highlight the potential importance of the relationship between dietary patterns or quality and mental health early in the life span.

The association between diet quality, dietary patterns and depression in adults: a systematic review

BackgroundRecent evidence suggests that diet modifies key biological factors associated with the development of depression; however, associations between diet quality and depression are not fully understood. We performed a systematic review to evaluate existing evidence regarding the association between diet quality and depression.MethodA computer-aided literature search was conducted using Medline, CINAHL, and PsycINFO, January 1965 to October 2011, and a best-evidence analysis performed.ResultsTwenty-five studies from nine countries met eligibility criteria. Our best-evidence analyses found limited evidence to support an association between traditional diets (Mediterranean or Norwegian diets) and depression. We also observed a conflicting level of evidence for associations between (i) a traditional Japanese diet and depression, (ii) a “healthy” diet and depression, (iii) a Western diet and depression, and (iv) individuals with depression and the likelihood of eating a less healthy diet.ConclusionTo our knowledge, this is the first review to synthesize and critically analyze evidence regarding diet quality, dietary patterns and depression. Further studies are urgently required to elucidate whether a true causal association exists.

Prevalence of Obesity and the Relationship between the Body Mass Index and Body Fat: Cross-Sectional, Population-Based Data

Background Anthropometric measures such as the body mass index (BMI) and waist circumference are widely used as convenient indices of adiposity, yet there are limitations in their estimates of body fat. We aimed to determine the prevalence of obesity using criteria based on the BMI and waist circumference, and to examine the relationship between the BMI and body fat. Methodology/Principal Findings This population-based, cross-sectional study was conducted as part of the Geelong Osteoporosis Study. A random sample of 1,467 men and 1,076 women aged 20–96 years was assessed 2001–2008. Overweight and obesity were identified according to BMI (overweight 25.0–29.9 kg/m2; obesity ≥30.0 kg/m2) and waist circumference (overweight men 94.0–101.9 cm; women 80.0–87.9 cm; obesity men ≥102.0 cm, women ≥88.0 cm); body fat mass was assessed using dual energy X-ray absorptiometry; height and weight were measured and lifestyle factors documented by self-report. According to the BMI, 45.1% (95%CI 42.4–47.9) of men and 30.2% (95%CI 27.4–33.0) of women were overweight and a further 20.2% (95%CI 18.0–22.4) of men and 28.6% (95%CI 25.8–31.3) of women were obese. Using waist circumference, 27.5% (95%CI 25.1–30.0) of men and 23.3% (95%CI 20.8–25.9) of women were overweight, and 29.3% (95%CI 26.9–31.7) of men and 44.1% (95%CI 41.2–47.1) of women, obese. Both criteria indicate that approximately 60% of the population exceeded recommended thresholds for healthy body habitus. There was no consistent pattern apparent between BMI and energy intake. Compared with women, BMI overestimated adiposity in men, whose excess weight was largely attributable to muscular body builds and greater bone mass. BMI also underestimated adiposity in the elderly. Regression models including gender, age and BMI explained 0.825 of the variance in percent body fat. Conclusions/Significance As the BMI does not account for differences in body composition, we suggest that gender- and age-specific thresholds should be considered when the BMI is used to indicate adiposity.

Habitual physical activity and the risk for depressive and anxiety disorders among older men and women

BACKGROUND Regular physical activity is generally associated with psychological well-being, although there are relatively few prospective studies in older adults. We investigated habitual physical activity as a risk factor for de novo depressive and anxiety disorders in older men and women from the general population. METHODS In this nested case-control study, subjects aged 60 years or more were identified from randomly selected cohorts being followed prospectively in the Geelong Osteoporosis Study. Cases were individuals with incident depressive or anxiety disorders, diagnosed using the Structured Clinical Interview for DSM-IV-TR (SCID-I/NP); controls had no history of these disorders. Habitual physical activity, measured using a validated questionnaire, and other exposures were documented at baseline, approximately four years prior to psychiatric interviews. Those with depressive or anxiety disorders that pre-dated baseline were excluded. RESULTS Of 547 eligible subjects, 14 developed de novo depressive or anxiety disorders and were classified as cases; 533 controls remained free of disease. Physical activity was protective against the likelihood of depressive and anxiety disorders; OR = 0.55 (95% CI 0.32-0.94), p = 0.03; each standard deviation increase in the transformed physical activity score was associated with an approximate halving in the likelihood of developing depressive or anxiety disorders. Leisure-time physical activity contributed substantially to the overall physical activity score. Age, gender, smoking, alcohol consumption, weight and socioeconomic status did not substantially confound the association. CONCLUSION This study provides evidence consistent with the notion that higher levels of habitual physical activity are protective against the subsequent risk of development of de novo depressive and anxiety disorders.

Socioeconomic status and risk factors for obesity and metabolic disorders in a population-based sample of adult females.

OBJECTIVES The association between lower socioeconomic status (SES), obesity, lifestyle choices and adverse health consequences are well documented, however to date the relationship between these variables and area-based SES (equivalised for advantage and disadvantage) has not been examined simultaneously in one population or with more than tertiary divisions of SES. We set out to examine the risk factors for obesity and metabolic disorders in the same population across quintiles of area-based SES. METHODS We performed a descriptive cross-sectional study using existing data from a population-based random selection of women aged 20-92 years (n=1110) recruited from the Barwon Statistical Division, South Eastern Australia. RESULTS All measures of adiposity were inversely associated with SES, and remained significant after adjusting for age. Lifestyle choices associated with adiposity and poorer health, including smoking, larger serving sizes of foods, and reduced physical activity, were significantly associated with individuals from lower SES groups. CONCLUSIONS Greater measures of adiposity and less healthy lifestyle choices were observed in individuals from lower SES. Significant differences in body composition were identified between quintiles 1 and 5, whereas subjects in the mid quintiles had relatively similar measures. The inverse relationship between SES, obesity and less healthy lifestyle underscores the possibility that these associations may be causal and should be investigated further.

The association between socioeconomic status and osteoporotic fracture in population-based adults: a systematic review

SummaryAlthough socioeconomic status (SES) is inversely related to most diseases, this systematic review showed a paucity of good quality data examining influences of SES on osteoporotic fracture to confirm this relationship. Further research is required to elucidate the issue and any underlying mechanisms as a necessary precursor to considering intervention implications.IntroductionThe association between socioeconomic status (SES) and musculoskeletal disease is little understood, despite there being an inverse relationship between SES and most causes of morbidity. We evaluated evidence of SES as a risk factor for osteoporotic fracture in population-based adults.MethodsComputer-aided search of Medline, EMBASE, CINAHL, and PsychINFO from January 1966 until November 2007 was conducted. Identified studies investigated the relationship between SES parameters of income, education, occupation, type of residence and marital status, and occurrence of osteoporotic fracture. A best-evidence synthesis was used to summarize the results.ResultsEleven studies were identified for inclusion, which suggested a lack of literature in the field. Best evidence analysis identified strong evidence for an association between being married/living with someone and reduced risk of osteoporotic fracture. Limited evidence exists of the relationship between occupation type or employment status and fracture, or for type of residence and fracture. Conflicting evidence exists for the relationship between osteoporotic fracture and level of income and education.ConclusionLimited good quality evidence exists of the role SES might play in osteoporotic fracture. Further research is required to identify whether a relationship exists, and to elucidate underlying mechanisms, as a necessary precursor to considering intervention implications.

Behavioural and physical characteristics associated with vitamin D status in women.

For most people in Australia, the primary source of vitamin D is casual exposure to sunlight. Hypovitaminosis D has been reported for high-risk populations, but little has been documented for women of all ages living in the community. Using cross-sectional data, we aimed to describe physical and behavioural characteristics associated with serum 25-hydroxyvitamin D (25OHD) for such women and to determine the association of serum 25OHD with hypertension and bone health. Serum 25OHD, parathyroid hormone (PTH), blood pressure, bone mineral density (BMD) and anthropometry were measured in a random sample of 861 women aged 20-92 years enrolled in the Geelong Osteoporosis Study, set in a temperate region at latitude 38-39 degrees S. Lifestyle factors (including diet, smoking, medication use, socio-economic status, residence, education, occupation, and physical activity) were documented by questionnaire. In season-adjusted models for women aged 20-54 years, physical activity and living with a partner were independently and positively associated with serum 25OHD; associations with weight and waist-hip ratio were negative. Among older women, physical activity, vitamin D intake and urban dwelling were positively associated with serum 25OHD; age, weight and smoking were negative. Compared with the lowest tertile, those in the highest serum 25OHD tertile were less likely to have elevated serum PTH (adjusted OR=0.25, 95% CI 0.16-0.41) and high blood pressure (adjusted OR=0.40, 95% CI 0.22-0.72), and more likely to have normal hip and spine BMD (adjusted OR=1.65, 95% CI 1.08-2.52). In multivariable models adjusting for season, age, weight (and height), BMD was associated with serum 25OHD at the spine, hip and whole body; no associations were detected at the forearm and no other characteristics were identified as confounders. Factors associated with high vitamin D status generally reflected healthy body habitus and active lifestyles. In contrast, excessive weight and smoking were associated with poorer vitamin D status. Women with high vitamin D were less likely to have elevated PTH, hypertension or bone deficits than women with poor levels.

Association between socioeconomic status and bone mineral density in adults : a systematic review

SummaryFor most causes of mortality and morbidity, a socioeconomic gradient exists; however, this systematic review identified limited evidence for the role of education on bone mineral density (BMD). Further research is required to build upon the current paucity of data examining influences of socioeconomic status (SES) on BMD, especially in men.IntroductionFor most causes of mortality and morbidity, a socioeconomic gradient exists, although little is understood of the relationship between BMD and SES. We systematically evaluated evidence of SES as a risk factor for low BMD at the clinically relevant sites of hip and spine in adults.MethodsWe conducted a computer-aided search of Medline, EMBASE, CINAHL, and PsychINFO from January 1, 1966 until December 31, 2008. Reviewed studies investigated the relationship between SES parameters of income, education, and occupation, and the level of BMD. Studies were rated based on their methodological quality, and a best-evidence synthesis was used to summarise the results.ResultsOne case-control and seven cross-sectional studies were identified for inclusion, of which four cross-sectional studies were high-quality. Best-evidence analysis identified consistent, yet limited, evidence for a positive association between educational attainment and BMD in women. No evidence was available regarding an association between income or occupation and BMD in either gender, or education and BMD in men.ConclusionsLimited good quality evidence exists for the role that education level may play in BMD levels. Cohort studies are required to examine the relationship between individual SES parameters and BMD in order to identify potential intervention targets.

Don't Worry, be Active: Positive Affect and Habitual Physical Activity

Objective: The aim of ths study was to examine the association between habitual physical activity and positive and negative affect. Method: This cross-sectional study included 276 women aged 20 +, from the Geelong Osteoporosis Study. Habitual physical activity and other lifestyle exposures were assessed by questionnaire, concurrent with anthropometric assessments. Physical activity was categorized as very active, moderately active or sedentary. Positive and negative affect scores were derived from the validated 20 item Positive and Negative Affect Schedule (PANAS) self-report and were categorized into tertiles. Results: There was a pattern of lower positive affect scores for lower levels of physical activity. With very active as the reference category, the odds for having a positive affect score in the highest tertile were sequentially lower for those who were moderately active (OR = 0.53, 95%CI 0.28–1.01) and sedentary (OR = 0.28, 95%CI 0.10–0.75). Associations were sustained after adjusting for body mass index and polypharmacy (OR = 0.50, 95%CI 0.26–0.96 and OR = 0.25, 95%CI 0.09–0.72, respectively). These associations were not explained by age, negative affect score or other exposures. No association was detected between physical activity and negative affect scores. Conclusions: This study reports that higher positive affect scores, encompassing emotions such as interest, excitement, enthusiasm and alertness, are associated with higher levels of habitual physical activity. These observations warrant further investigations into possible mechanistic interplay between neurobiological and psychosocial factors that underpin this association.