The risk of acute events among patients with sickle cell disease in relation to early or late initiation of care at a specialist center: evidence from a retrospective cohort study.

BACKGROUND: The greatest disease burden of sickle cell disease occurs early in life. Understanding factors that reduce disease related events in this period is therefore important. Hence, we assessed the impact of early care at a specialist center on the incidence of acute events during the first five years. METHODS: This was a retrospective cohort study among Jamaican children with sickle cell disease. Medical records of patients born January, 2004 to December, 2009, who were registered at the Sickle Cell Unit, a specialist care facility, were abstracted for dates of initiation to care, first occurrence and frequency of the outcomes of interest (vaso-occlusive crises, acute splenic sequestration, acute chest syndrome, and infection). Patients were classified according to whether initiation of care was before (early) or after 5 months of age (late). Using standardized t-tests, χ2 tests, and a multiple-failure survival analysis the rates of acute events between groups were compared. RESULTS: Of the total study group (n= 290), homozygous sickle cell disease accounted for 97% and 95% of the early (n=113) and late groups (n=177) respectively. The mean age of presentation in the early and late group was 0.2 and 2.3 years (p<0.01), with a mean length of follow-up of 5.2 and 3.2 years respectively (p<0.01). Vaso-occlusive crisis (n=880) and acute chest syndrome (n= 571) together accounted for 91.6% of the total number of events (n=1584). The risk of vaso-occlusive crisis and acute chest syndrome (among patients who presented with these acute events) was significantly higher in the "late" group, by 43% (Incidence rate ratio, (IRR) = 1.43, p<0.001); 95% CI (1.18-1.72) and 40% (IRR=1.40. p=0.002), 95% CI (1.12-1.75) respectively compared to "early" group. There was no difference in risk between groups for acute splenic sequestration and infection among persons presenting with these events. CONCLUSION: The risk of acute events in children with sickle cell disease exposed to early care at a specialist care is significantly less. Therefore, widespread screening with rapid referral to a specialist center stands to reduce substantial morbidity in Jamaica and other regions with high prevalence of sickle cell disease.

Understanding neighbourhood retail food environmental mechanisms influencing BMI in the Caribbean: a multilevel analysis from the Jamaica Health and Lifestyle Survey: a cross-sectional study.

OBJECTIVE: To derive estimates of the associations between measures of the retail food environments and mean body mass index (BMI) in Jamaica, a middle-income country with increasing prevalence of obesity. DESIGN: Cross-sectional study. SETTING: Data from the Jamaica Health and Lifestyle Survey 2008 (JHLS II), a nationally representative population-based survey that recruited persons at their homes over a 4-month period from all 14 parishes and 113 neighbourhoods defined as enumeration districts. PARTICIPANTS: A subsample of 2529 participants aged 18-74 years from the JHLS II who completed interviewer-administered surveys, provided anthropometric measurements and whose addresses were geocoded. PRIMARY OUTCOME MEASURE: Mean BMI, calculated as weight divided by height squared (kg/m2). RESULTS: There was significant clustering across neighbourhoods for mean BMI (intraclass correlation coefficients=4.16%). Fully adjusted models revealed higher mean BMI among women, with further distance away from supermarkets (ß=0.12; 95% CI 8.20×10-3, 0.24; p=0.036) and the absence of supermarkets within a 1 km buffer zone (ß=1.36; 95% CI 0.20 to 2.52; p=0.022). A 10 km increase in the distance from a supermarket was associated with a 1.7 kg/m2 higher mean BMI (95% CI 0.03 to 0.32; p=0.020) in the middle class. No associations were detected with fast-food outlets or interaction by urbanicity. CONCLUSIONS: Higher mean BMI in Jamaicans may be partially explained by the presence of supermarkets and markets and differ by sex and social class. National efforts to curtail obesity in middle-income countries should consider interventions focused at the neighbourhood level that target the location and density of supermarkets and markets and consider sex and social class-specific factors that may be influencing the associations.

Neighbourhood characteristics and cumulative biological risk: evidence from the Jamaica Health and Lifestyle Survey 2008: a cross-sectional study.

OBJECTIVE: To examine whether neighbourhood characteristics are associated with cumulative biological risk (CBR) and sex differences in CBR in a nationally representative sample in Jamaica, a small island developing country with increasing prevalence of non-communicable diseases (NCDs). DESIGN: Cross-sectional study SETTING: A population-based cross-sectional survey, the Jamaica Health and Lifestyle Survey 2008 (JHLS II) recruited persons at their homes over a 4 month period from all 14 parishes and 113 neighbourhoods defined as enumeration districts (EDs). PARTICIPANTS: 2544 persons aged 15-74 years old from the 2008 Jamaica Health and Lifestyle Survey (JHLS II), who completed interviewer-administered questionnaires and had biomarkers assessed, and whose home addresses could be reliably geocoded. PRIMARY OUTCOME: A summary measure CBR was created using seven markers-systolic and diastolic blood pressure readings, waist circumference, body mass index, total cholesterol, fasting blood glucose levels and self-reported asthma. Weighted multilevel models examined clustering, using the intraclass correlation coefficient (ICC), of CBR across neighbourhoods and the impact of neighbourhood characteristics (recreational space availability and neighbourhood disorder) on CBR. RESULTS: Women had significantly higher mean CBR scores than men across all age groups. There was significant clustering of CBR by ED, and among women versus men (ICC: F=6.9%, M=0.7%). Women living in more disordered neighbourhoods were 26% more likely to have high CBR as those in less disordered ones (aOR=1.26, 95% CI=1.08 to 1.47; p<0.05). Individuals living in EDs with greater recreational space availability were 25% less likely to have a high CBR (aOR=0.75, 95% CI=0.64 to 0.90; p<0.05). CONCLUSIONS: Policy-makers in Jamaica should pay greater attention to neighbourhood factors such as recreational space availability and neighbourhood disorder that may contribute to CBR in any effort to curtail the epidemic of NCDs.

Associations between neighborhood effects and physical activity, obesity, and diabetes: The Jamaica Health and Lifestyle Survey 2008.

OBJECTIVE: To examine the impact of neighborhood disorder, perceived neighborhood safety, and availability of recreational facilities on prevalence of physical activity (PA), obesity, and diabetes mellitus (DM). STUDY DESIGN AND SETTING: Multilevel analyses were conducted among 2,848 respondents from the 2007-08 Jamaica Health and Lifestyle Survey. Neighborhood effects were based on aggregated interviewer responses to systematic social observation questions. Mixed-effect logistic regression models were created to assess the relationship between neighborhood indicators and DM and the modifiable risk factors PA and overweight/obesity. RESULTS: There was significant clustering in PA levels of 20 minutes at least once per week (intraclass correlation coefficient [ICC] = 10.7%), low/no PA (ICC = 7.22%), diabetes (ICC = 5.44%), and obesity (ICC = 3.33%) across neighborhoods. Greater levels of neighborhood disorder, home disorder, and counterintuitively recreational space availability were associated with higher levels of low/no PA among women. There was significant interaction by sex between neighborhood infrastructure and overweight/obesity with a significant association in men (odds ratio [OR] = 1.16; 95% confidence interval [CI] = 1.05, 1.28) but not women (OR = 1.01; 95% CI = 0.95, 1.07). CONCLUSION: Differences in PA and obesity-related outcomes among Jamaicans may be partially explained by characteristics of the neighborhood environment and differ by sex. Future studies must be conducted to determine the mechanistic pathways through which the neighborhood environment may impact such outcomes to better inform prevention efforts.