Cartilage loss occurs in the same subregions as subchondral bone attrition: a within-knee subregion-matched approach from the Multicenter Osteoarthritis Study

OBJECTIVE

By magnetic resonance imaging (MRI), subchondral bone attrition (SBA) can be seen in early osteoarthritis (OA), but the significance of this is unknown. We therefore evaluated whether SBA was associated with cartilage loss within the same subregion of the knee.

METHODS

The Multicenter Osteoarthritis Study is a cohort of individuals who have or are at high risk for knee OA. At baseline and 30 months, participants' knee MRIs were graded using the Whole-Organ Magnetic Resonance Imaging Score in the 10 subregions of the tibiofemoral joint for cartilage morphology and SBA. We conducted analyses within a knee to eliminate between-person confounding, using an M:N (cases:controls) matched case-control approach with the 10 subregions of a person's knee forming a matched set. Cases within a knee were defined as subregions with cartilage loss, while controls were subregions in that same knee without cartilage loss. We evaluated the association of cartilage loss over 30 months with the presence of baseline SBA in the same subregion within that knee using conditional logistic regression.

RESULTS

SBA was associated with an odds ratio of 7.5 (95% confidence interval 5.6-9.9, P < 0.0001) for cartilage loss in the same subregion compared with subregions without any baseline SBA in our sample of 459 knees from participants, 64% of whom were women, with a mean age of 63 years and a mean body mass index of 30.5 kg/m(2).

CONCLUSION

SBA is strongly associated with cartilage loss within the same subregion of a knee. SBA may directly influence overlying cartilage loss or serve as a marker of an area undergoing great compressive stress and in which cartilage loss is inevitable.

Patellar cartilage: T2 values and morphologic abnormalities at 3.0-T MR imaging in relation to physical activity in asymptomatic subjects from the osteoarthritis initiative

PURPOSE

To study the interrelationship between patella cartilage T2 relaxation time, other knee abnormalities, and physical activity levels in asymptomatic subjects from the Osteoarthritis Initiative (OAI) incidence cohort.

MATERIALS AND METHODS

The study had institutional review board approval and was HIPAA compliant. One hundred twenty subjects from the OAI without knee pain (age, 45-55 years) and with risk factors for knee osteoarthritis (OA) were studied by using knee radiographs, 3.0-T knee magnetic resonance (MR) images (including intermediate-weighted fast spin-echo and T2 mapping sequences), and the Physical Activity Scale for the Elderly. MR images of the right knee were assessed by two musculoskeletal radiologists for the presence and grade of abnormalities. Segmentation of the patella cartilage was performed, and T2 maps were generated. Statistical significance was determined by using analysis of variance, chi(2) analysis, correlation coefficient tests, the Cohen kappa, and a multiple linear regression model.

RESULTS

Cartilage lesions were found in 95 (79.0%) of 120 knees, and meniscal lesions were found in 54 (45%) of 120 knees. A significant correlation between patella cartilage T2 values and the severity and grade of cartilage (P = .0025) and meniscus (P = .0067) lesions was demonstrated. Subjects with high activity levels had significantly higher prevalence and grade of abnormalities and higher T2 values (48.7 msec +/-4.35 vs 45.8 msec +/-3.93; P < .001) than did subjects with low activity levels.

CONCLUSION

Middle-aged asymptomatic individuals with risk factors for knee OA had a high prevalence of cartilage and meniscus knee lesions. Physically active individuals had more knee abnormalities and higher patellar T2 values. Additional studies will be needed to determine causality.

Prospective Study of Vitamin D Levels in Sydney Patients with a New Diagnosis of Breast Cancer

Background: Vitamin D deficiency has been associated with malignancy in many reported studies. More recently an association has emerged between low levels of vitamin D and poorer outcome in breast cancer. Australian recommendations for vitamin D are defined as deficient if 25-OH vitamin D levels are ≤ 50nmol/L and severely deficient if ≤12.5nmol/L. We hypothesise that lower levels of vitamin D are associated with a more advanced disease at diagnosis.Methods: We conducted a prospective study in patients with a new diagnosis of breast cancer who presented to our area health service from January 1st 2008 to October 1st 2008. Patients were also included if their diagnosis occurred in the preceding 6 months and were referred onto the multidisciplinary breast care team for treatment in this time period. 25-OH vitamin D levels were measured for each patient during staging and details collected about each patients breast cancer characteristics. Patients completed a questionnaire assessing comorbidities, medications, diet and lifestyle effects which were likely to influence vitamin D levels. We used stage, disease requiring chemotherapy, and the need for mastectomy as surrogate endpoints for assessing disease extent.Results: 166 patients were recruited with a median age of 58 (range 21-100). The median vitamin D level was 48 (range of &lt;10 to 170). 53% (n=88) patient were deficient (25-OH vitamin D ≤ 50nmol/L), 2% (n=3) patients were severely deficient (25-OH vitamin D ≤ 12.5nmol/L) and only 14% had sufficient levels (25-OH vitamin D &gt;75nmol/L). The majority of patients reported the recommended sun exposure during weekdays (77%) and on weekends (86%). Most were had fair or medium skin tones (83%) and less than 10% wore sunscreen daily. Only 22% of patients had a potential identifiable cause for vitamin D deficiency. Vitamin D levels did not correlate directly with stage of disease (RR 1.03, 95% CI 0.86-1.23 p=0.85), however other surrogates for more advanced disease including the need for more aggressive treatment either with chemotherapy (RR 1.30, 95% CI 1.05-1.61 p=0.02) or mastectomy (RR 1.67 95% CI 1.03-2.7 p=0.04) were associated with low levels of vitamin D.Conclusions: Vitamin D deficiency is very prevalent in our population of patients diagnosed with breast cancer, despite perceived adequate sun exposure and lack of obvious cause. Lower levels of vitamin D did not directly correlate with more advanced stage of the disease at diagnosis; however patients with low levels of vitamin D were more likely to need chemotherapy or require mastectomy, which may suggest a more aggressive disease. The cause of breast cancer remains multifactorial and vitamin D deficiency is only one part of this complex disease.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6071.

Declines in physical activity and higher systolic blood pressure in adolescence

The authors examined the potential association between changes in the number of moderate-to-vigorous physical activity (MVPA) sessions per week, adiposity, and systolic blood pressure (SBP) during adolescence. SBP and anthropometric factors were assessed biannually (1999/2000, 2002, and 2004) in a cohort of 1,293 Canadian adolescents aged 12-13 years in 1999. Self-reported 7-day recall data on MVPA sessions >or=5 minutes in duration were collected every 3 months over the 5-year period. Estimates of initial level and rate of decline in number of MVPA sessions per week from individual growth models were used as predictors of SBP in linear regression models. A decline of 1 MVPA session per week with each year of age was associated with 0.29-mm Hg and 0.19-mm Hg higher SBPs in girls and boys, respectively, in early adolescence (ages 12.8-15.1 years) and 0.40-mm Hg and 0.18-mm Hg higher SBPs, respectively, in late adolescence (ages 15.2-17.0 years). The associations were not attenuated by changes in body mass index, waist circumference, or skinfold thickness in girls during late adolescence. Although weaker, associations were evident in boys during late adolescence, as well as in both girls and boys during early adolescence. These results support prevention of declines in MVPA during adolescence to prevent higher blood pressure in youth.

Assessing the role of individual and neighbourhood characteristics in HIV testing: evidence from a population based survey

OBJECTIVES

Individuals living in deprived neighbourhoods have poor health outcomes, including human immunodeficiency virus (HIV) infection mortality. We assessed the association between individual and neighbourhood characteristics, and HIV testing across Canada.

METHODS

We used logistic regression modelling to evaluate this association in 2219 men and 2815 women, aged 18-54 years, in Canada, using data from the National Population Health Survey (1996/7),. Socio-economic characteristics and presence of a sexually transmitted infection (STI) were the individual level characteristics. Small area of residence was classified according to categories of material and social deprivation; these were the 'neighbourhood' variables in the model.

RESULTS

Ethnic minority women were less likely to report an HIV test than white women (OR 0.44, 95% CI: 0.23 to 0.86). Women without a regular doctor were significantly less likely to report ever having had an HIV test (OR 0.57, 95% CI: 0.35 to 0.93). Adjusting for individual level characteristics, we found that men and women living in the most materially deprived neighbourhoods were slightly less likely to report HIV testing than those living in the least deprived neighbourhoods (Men - OR 0.61, 95% CI: 0.34 to 1.08; Women - OR 0.62, 95% CI: 0.38 to 1.00).

DISCUSSION

Thus, living in poor neighbourhoods was associated with poor uptake of an HIV test. These economic disparities should be taken in account while designing future prevention strategies. Ethnic minority women were less likely to go for HIV testing and culturally appropriate messages may be required for prevention in ethnic minorities.

Decisions to seek healthcare based on family health history among urban Appalachian women

Family health history (FHH) is a valuable health promotion tool that can be used to assess disease risk and make lifestyle and screening recommendations. However, few FHH resources exist for medically underserved populations such as the urban Appalachian community in Cincinnati Ohio. Women of Appalachian heritage with less than a college education who did and did not participate in a prior FHH education session were interviewed by phone in a semi-structured format. Interviewees were asked to discuss their understanding of FHH and the role FHH played in seeking (or not seeking) medical care. Analysis of their discussion identified four overarching themes as well as a model identifying conditions that facilitated or impeded the choice to seek medical care based on FHH. Findings from this study may be used to develop targeted FHH educational interventions in the urban Appalachian and other communities.

Would achieving healthy people 2010's targets reduce both population levels and social disparities in heart disease?

BACKGROUND

The US Healthy People 2010 (HP2010) agenda set targets for major risk factors for coronary heart disease (CHD). However, the potential impact of achieving those risk factor reductions on both population levels and social disparities in CHD has not been quantified.

METHODS AND RESULTS

Data on 10-year risk of CHD (from the First National Health and Nutrition Examination Epidemiological Follow-Up study 1971 to 1982), prevalence of major CHD risk factors (from the National Health and Nutrition Examination Survey 2003 to 2004), and HP2010 targets for CHD risk factors (reduction of smoking rate to 12%, hypertension to 14%, high cholesterol levels to 17%, diabetes to 2.5%, and obesity to 15%) were used to estimate effects of different scenarios on population levels and social disparities in CHD. Over a 10-year period, the largest relative reductions in population levels of CHD (20.0% in men; 23.9% in women) would be achieved if all social groups met the HP2010 targets. CHD disparities would be most reduced if the less educated (absolute disparities reduced by 66.1% in men; 56.3% in women) and the low income group (absolute disparities reduced by 93.7% in men; 94.3% in women) achieved the targets before the most advantaged. These reductions are larger than those expected if targets were achieved overall for the population but relative social group differences in risk factors remained, or under leveling-up approaches in which the least advantaged achieved the current levels of risk factors of the most advantaged.

CONCLUSIONS

Interventions to reduce CHD risk factors to HP2010 targets that focus on all social groups would produce the best overall scenario for both population levels and disparities in CHD.

Convergence of body mass index of immigrants to the Canadian-born population: evidence from the National Population Health Survey (1994-2006)

Recent immigrants typically have better physical health than the native born population. However, this 'healthy immigrant effect' tends to gradually wane over time, with increasing length of residence in the host country. To assess whether the body mass index (BMI) of different immigrant groups converged to the Canadian population's levels, we estimated 12-year trajectories of changes in BMI (accounting for socio-demographic changes). Using data from seven longitudinal waves of the National Population Health Survey (1994 through 2006), we compared the changes in BMI (kg/m(2)) among three groups: white immigrants, non-white immigrants and Canadian born, aged 18-54 at baseline. We applied linear random effects models to evaluate these BMI separately in 2,504 males and 2,960 females. BMI increased in Canadian born, white immigrants, and non-white immigrants over the 12-year period. However, non-white immigrants (males and females) had a lower mean BMI than Canadian born individuals during this period [Males: -2.27, 95% Confidence interval (CI) -3.02 to -1.53; Females: -1.84, 95% CI -2.79 to -0.90]. In contrast, the mean BMI in white male immigrants and Canadian born individuals were similar (-0.32, 95% CI -0.91 to 0.27). Even after adjusting for time since immigration, non-white immigrants had lower BMI than white immigrants. White male immigrants were the only sub-group to converge to the BMI of the Canadian born population. These results indicate that the loss of 'healthy immigrant effect' with regard to convergence of BMI to Canadian levels may not be experienced equally by all immigrants in Canada.

Socioeconomic position, macroeconomic environment and overweight among adolescents in 35 countries

OBJECTIVE

It is important to understand levels and social inequalities in childhood overweight within and between countries. This study examined prevalence and social inequality in adolescent overweight in 35 countries, and associations with macroeconomic factors.

DESIGN

International cross-sectional survey in national samples of schools.

SUBJECTS

A total of 11-, 13- and 15-year-olds from 35 countries in Europe and North America in 2001-2002 (N=162 305).

MEASUREMENTS

The main outcome measure was overweight based on self-reported height and weight (body mass index cut-points corresponding to body mass index of 25 kg/m(2) at the age of 18 years). Measures included family and school affluence (within countries), and average country income and economic inequality (between countries).

RESULTS

There were large variations in adolescent overweight, from 3.5% in Lithuanian girls to 31.7% in boys from Malta. Prevalence of overweight was higher among children from less affluent families in 21 of 24 Western and 5 of 10 Central European countries. However, children from more affluent families were at higher risk of overweight in Croatia, Estonia and Latvia. In Poland, Lithuania, Macedonia and Finland, girls from less affluent families were more overweight whereas the opposite was found for boys. Average country income was associated with prevalence and inequality in overweight when considering all countries together. However, economic inequality as measured by the Gini coefficient was differentially associated with prevalence and socioeconomic inequality in overweight among the 23-high income and 10-middle income countries, with a positive relationship among the high income countries and a negative association among the middle income countries.

CONCLUSION

The direction and magnitude of social inequality in adolescent overweight shows large international variation, with negative social gradients in most countries, but positive social gradients, especially for boys, in some Central European countries. Macroeconomic factors are associated with the heterogeneity in prevalence and social inequality of adolescent overweight.

Cell survival under stress is enhanced by a mitochondrial ATP-binding cassette transporter that regulates hemoproteins

The ATP-binding cassette (ABC) transporter ABCB6 localizes to the mitochondria, where it imports porphyrins and up-regulates de novo porphyrin synthesis. If ABCB6 also increases the intracellular heme concentration, it may broadly affect the regulation and physiology of cellular hemoproteins. We tested whether the ability of ABCB6 to accelerate de novo porphyrin biosynthesis alters mitochondrial and extramitochondrial heme levels. ABCB6 overexpression increased the quantity of cytosolic heme but did not affect mitochondrial heme levels. We then tested whether the increased extramitochondrial heme would increase the concentration and/or activity of cellular hemoproteins (hemoglobin, catalase, and cytochrome c oxidase). ABCB6 overexpression increased the activity and quantity of hemoproteins found in several subcellular compartments, and reduction of ABCB6 function (by small interfering RNA or knockout) reversed these findings. In complementary studies, suppression of ABCB6 expression sensitized cells to stress induced by peroxide and cyanide, whereas overexpression of ABCB6 protected against both stressors. Our findings show that the ability of ABCB6 to increase cytosolic heme levels produces phenotypic changes in hemoproteins that protect cells from certain stresses. Collectively, these findings have implications for the health and survival of both normal and abnormal cells, which rely on heme for multiple cellular processes.

Strong association of MRI meniscal derangement and bone marrow lesions in knee osteoarthritis: data from the osteoarthritis initiative

INTRODUCTION

Meniscal damage is common in knee Osteoarthritis (OA) and predictive of structural progression, suggesting that their disruption plays a role in the development of OA. The bone marrow lesion (BML) is associated with pain and is a strong risk factor for structural progression. These lesions are associated with abnormal loading in a knee joint. Therefore, our hypothesis was that in those with symptomatic knee OA, large BMLs would be associated with ipsi-compartmental meniscal derangement.

METHODS

This was a cross-sectional study of a subsample of the Osteoarthritis Initiative where one set of magnetic resonance (MR) images from each participant was scored for tibiofemoral BMLs and meniscal derangement. We performed chi-squared tests comparing the prevalence of large BMLs in those with ipsi-compartmental meniscal derangement and those without.

RESULTS

160 Participants had a mean age of 61 (+/-9.9), mean BMI of 30.3 (+/-4.7) and 50% were female. 79% of medial and 39% of lateral menisci showed MRI (Magnetic Resonance Imaging) derangement. In those with medial meniscal MRI derangement, 44% had large medial BMLs while in those without medial meniscal derangement, 0% had large BMLs. Similar results were seen in the lateral compartment.

CONCLUSION

Medial and lateral MRI meniscal derangement are highly prevalent in symptomatic knee OA and BMLs are highly associated with ipsi-compartmental MRI meniscal derangement.

Large granular lymphocytic leukaemia complicated with histiocytic sarcoma in a dog : clinical communication

A 10-year-old castrated male Golden retriever, weighing 36.3 kg was referred for evaluation owing to a decline in general condition. Findings from the complete blood count revealed a marked lymphocytosis (113 000/µℓ). Examination of Wright-Giemsa-stained films of peripheral blood revealed the presence of large granular lymphocytes (LGL). Seventy-two per cent (81 360/µℓ) of the lymphocytes were found to be 12-17 µm in diameter, containing nuclei with mature clumped chromatin and abundant lightly basophilic cytoplasm with a variable number of fine azurophilic granules. Based on these findings this case was diagnosed as LGL leukaemia. As a result of multiple-agent chemotherapy, the markedly elevated levels of lymphocytes gradually decreased to 7500/µℓ on day 122 and the patient maintained a good quality of life for the following 3 months. However, on around day 237, a soft, raised, bosselated mass on the labial region was noted. The dog was diagnosed as having histiocytic sarcoma based on cytological and histological examination of the mass. Shortly after diagnosis, the dog developed sudden onset of central nervous system signs and died on day 270. A common outcome of canine LGL is the development of acute blast crisis or lymphoma. However, this case was notable for complication with histiocytic sarcoma from another origin.

Socioeconomic inequality in exposure to bullying during adolescence: a comparative, cross-sectional, multilevel study in 35 countries

OBJECTIVES

We examined the socioeconomic distribution of adolescent exposure to bullying internationally and documented the contribution of the macroeconomic environment.

METHODS

We used an international survey of 162,305 students aged 11, 13, and 15 years from nationally representative samples of 5998 schools in 35 countries in Europe and North America for the 2001-2002 school year. The survey used standardized measures of exposure to bullying and socioeconomic affluence.

RESULTS

Adolescents from families of low affluence reported higher prevalence of being victims of bullying (odds ratio [OR] = 1.13; 95% confidence interval [CI] = 1.10, 1.16). International differences in prevalence of exposure to bullying were not associated with the economic level of the country (as measured by gross national income) or the school, but wide disparities in affluence at a school and large economic inequality (as measured by the Gini coefficient) at the national level were associated with an increased prevalence of exposure to bullying.

CONCLUSIONS

There is socioeconomic inequality in exposure to bullying among adolescents, leaving children of greater socioeconomic disadvantage at higher risk of victimization. Adolescents who attend schools and live in countries where socioeconomic differences are larger are at higher risk of being bullied.

Trends in area-socioeconomic and race-ethnic disparities in breast cancer incidence, stage at diagnosis, screening, mortality, and survival among women ages 50 years and over (1987-2005)

BACKGROUND

Breast cancer is the most commonly diagnosed cancer and the second leading cause of cancer death among women in the United States and varies systematically by race-ethnicity and socioeconomic status. Previous research has often focused on disparities between particular groups, but few studies have summarized disparities across multiple subgroups defined by race-ethnic and socioeconomic position.

METHODS

Data on breast cancer incidence, stage, mortality, and 5-year cause-specific probability of death (100 - survival) were obtained from the Surveillance, Epidemiology, and End Results program and data on mammography screening from the National Health Interview Survey from 1987 to 2005. We used four area-socioeconomic groups based on the percentage of poverty in the county of residence (<10, 10-15, 15-20, +20%) and five race-ethnic groups (White, Black, Asian, American Indian, and Hispanic). We used summary measures of disparity based on both rate differences and rate ratios.

RESULTS

From 1987 to 2004, area-socioeconomic disparities declined by 20% to 30% for incidence, stage at diagnosis, and 5-year cause-specific probability of death, and by roughly 100% for mortality, whether measured on the absolute or relative scale. In contrast, relative area-socioeconomic disparities in mammography use increased by 161%. Absolute race-ethnic disparities declined across all outcomes, with the largest reduction for mammography (56% decline). Relative race-ethnic disparities for mortality and 5-year cause-specific probability of death increased by 24% and 17%, respectively.

CONCLUSIONS

Our analysis suggests progress towards race-ethnic and area-socioeconomic disparity goals for breast cancer, especially when measured on the absolute scale. However, greater progress is needed to address increasing relative socioeconomic disparities in mammography and race-ethnic disparities in mortality and 5-year cause-specific probability of death.

Differences between women's and men's socioeconomic inequalities in health: longitudinal analysis of the Canadian population, 1994-2003

BACKGROUND

Socioeconomic inequalities in health are ubiquitous in developed countries; however, whether these inequalities differ between women and men over time is less clear.

OBJECTIVE

To estimate the potentially different health effects of changes in socioeconomic position (SEP) on changes in health for working-age women and men over a 10-year period. Three main questions were addressed: (1) are there health differences between women and men over time, (2) do changes in SEP lead to health inequalities and (3) do changes in SEP impact health differently for women and men?

METHODS

Generalised estimating equations models were used to analyse cycles 1-5 of the Canadian National Population Health Survey for four measures of health, number of chronic conditions, self-rated health, functional health and mental distress, and three measures of SEP, income, education and employment status.

RESULTS

Health inequalities by sex/gender and by changes in SEP were present for all four outcomes in age-adjusted models; however, after controlling for time-dependent social structure, behaviour, and psychosocial factors the relationships persisted only for chronic conditions and psychological distress. There was no evidence that these effects differed, over time, between women and men.

CONCLUSIONS

Men and women in this nationally representative sample of Canadians do not differentially embody changes in SEP, although both sex/gender and changes in SEP independently impact health.