Epidemiology and clinical outcomes of light-chain amyloidosis in Sweden: A nationwide population-based study.

OBJECTIVES: This study evaluated data from six Swedish national registries to fill current evidence gaps on the epidemiology, clinical burden, and overall survival (OS) associated with light-chain (AL) amyloidosis. METHODS: Patients newly diagnosed with AL amyloidosis were identified using six linked Swedish nationwide population-based registers. For each case, individuals from the general population were selected and matched with a maximum ratio of 1:5 based on age, sex, calendar year, and county. RESULTS: 846 patients newly diagnosed with AL amyloidosis and 4227 demographically matched individuals were identified. From 2011 to 2019, annual AL amyloidosis incidence increased from 10.5 to 15.1 cases per million. At baseline, patients with AL amyloidosis had a significantly higher disease burden including higher rates of cardiac and renal failure relative to the comparison group. Among patients with AL amyloidosis, 21.5% had incident heart failure and 17.1% had incident renal failure after initial diagnosis. Median OS for patients with AL amyloidosis was 56 months versus not reached in the matched general population comparison group. CONCLUSION: The incidence of newly diagnosed AL amyloidosis in Sweden increased over time with AL amyloidosis being associated with a higher risk of cardiac/renal failure and all-cause mortality compared with the general population.

Risk of depression, suicide and psychosis with hydroxychloroquine treatment for rheumatoid arthritis: a multinational network cohort study.

OBJECTIVES: Concern has been raised in the rheumatology community regarding recent regulatory warnings that HCQ used in the coronavirus disease 2019 pandemic could cause acute psychiatric events. We aimed to study whether there is risk of incident depression, suicidal ideation or psychosis associated with HCQ as used for RA. METHODS: We performed a new-user cohort study using claims and electronic medical records from 10 sources and 3 countries (Germany, UK and USA). RA patients ≥18 years of age and initiating HCQ were compared with those initiating SSZ (active comparator) and followed up in the short (30 days) and long term (on treatment). Study outcomes included depression, suicide/suicidal ideation and hospitalization for psychosis. Propensity score stratification and calibration using negative control outcomes were used to address confounding. Cox models were fitted to estimate database-specific calibrated hazard ratios (HRs), with estimates pooled where I2 <40%. RESULTS: A total of 918 144 and 290 383 users of HCQ and SSZ, respectively, were included. No consistent risk of psychiatric events was observed with short-term HCQ (compared with SSZ) use, with meta-analytic HRs of 0.96 (95% CI 0.79, 1.16) for depression, 0.94 (95% CI 0.49, 1.77) for suicide/suicidal ideation and 1.03 (95% CI 0.66, 1.60) for psychosis. No consistent long-term risk was seen, with meta-analytic HRs of 0.94 (95% CI 0.71, 1.26) for depression, 0.77 (95% CI 0.56, 1.07) for suicide/suicidal ideation and 0.99 (95% CI 0.72, 1.35) for psychosis. CONCLUSION: HCQ as used to treat RA does not appear to increase the risk of depression, suicide/suicidal ideation or psychosis compared with SSZ. No effects were seen in the short or long term. Use at a higher dose or for different indications needs further investigation. TRIAL REGISTRATION: Registered with EU PAS (reference no. EUPAS34497; http://www.encepp.eu/encepp/viewResource.htm? id=34498). The full study protocol and analysis source code can be found at https://github.com/ohdsi-studies/Covid19EstimationHydroxychloroquine2.

Diagnostic delay and characterization of the clinical prodrome in AL amyloidosis among 1523 US adults diagnosed between 2001 and 2019.

Light-chain (AL) amyloidosis is a multisystem disorder with a high early mortality and diagnostic delays of >1 year from symptom onset. This retrospective observational study sought to characterize the clinical prodrome and diagnostic delay to inform early detection. We identified 1523 adults with newly diagnosed AL amyloidosis in the Optum de-identified Clinformatics® Datamart US healthcare claims database as those with ≥2 new diagnosis codes for AL or other amyloidosis in 90 days with ≥1 multiple myeloma treatment within 730 days, excluding patients with prior hereditary or secondary amyloidosis and Familial Mediterranean Fever. We considered 34 signs/symptoms using diagnosis codes in all observable time on or before AL amyloidosis diagnosis. Sign/symptom prevalence was compared to that of 1:4 matched population controls. The overlap and sequence of signs/symptoms and the median time from first sign/symptom to AL amyloidosis diagnosis were explored. Healthcare utilization was summarized. The most common individual AL amyloidosis signs/symptoms were malaise/fatigue (61%) and dyspnea (59%). Cardiac signs/symptoms were observed in 77% of patients, followed by renal (62%) and neurologic (59%) signs/symptoms. Multisystem involvement (≥3 systems) was present in 54%. Monoclonal gammopathy was detected in 29% before diagnosis. Median time from symptom onset to AL amyloidosis diagnosis was 2.7 years. Healthcare utilization was high between first AL amyloidosis signs/symptoms and diagnosis, with 50% visiting ≥5 physician types. AL amyloidosis patients have a lengthy and complex clinical prodrome. Novel approaches to early diagnosis are needed to improve outcomes.

Cause-specific mortality among Medicare beneficiaries with newly diagnosed non-Hodgkin lymphoma subtypes.

BACKGROUND: As the US population ages and non-Hodgkin lymphoma (NHL)-specific mortality declines, deaths from causes other than NHL will become increasingly important in treatment decision making for older patients with NHL. The objective of the current study was to describe how the 5-year cumulative incidence of NHL-specific and other-cause mortality varies by subtype, age, comorbidity level, and time since diagnosis in older patients. METHODS: Using the Surveillance, Epidemiology, and End Results cancer registry data linked to Medicare claims, patients aged ≥66 years were identified at the time of diagnosis with a first, primary NHL diagnosis from 2004 through 2013. Death certificate data and Fine-Gray competing risks models were used to estimate the 5-year cumulative incidence of NHL-specific and other-cause mortality by NHL subtype, age, and comorbidity level. Estimates were displayed over time using stacked cumulative incidence curves. RESULTS: Among 30,666 patients with NHL, 32% died of NHL and 13% died of other causes within 5 years of diagnosis. The cumulative incidence of other-cause mortality increased with age and comorbidity level for all subtypes. Among patients with aggressive NHL subtypes, NHL-specific mortality exceeded other-cause mortality across all age groups, comorbidity levels, and number of years after diagnosis. For patients with indolent NHL subtypes, other-cause mortality was similar to or exceeded NHL-specific mortality, especially among older patients with severe comorbidity or with the indolent marginal zone, lymphoplasmacytic, and mycosis fungoides subtypes. CONCLUSIONS: The findings of the current study suggest that mortality from causes other than NHL are important for patients of an older age, with a higher comorbidity level, and with indolent disease. Evidence from the current study can guide the development of tools for estimating individual prognosis that inform treatment discussions in patients with NHL.

Comparison of Medicare Claims-based Proxy Measures of Poor Function and Associations With Treatment Receipt and Mortality in Older Colon Cancer Patients.

BACKGROUND: Multiple claims-based proxy measures of poor function have been developed to address confounding in observational studies of drug effects in older adults. We evaluated agreement between these measures and their associations with treatment receipt and mortality in a cohort of older colon cancer patients. METHODS: Medicare beneficiaries age 66+ diagnosed with stage II-III colon cancer were identified in the Surveillance, Epidemiology, and End Results-Medicare database (2004-2011). Poor function was operationalized by: (1) summing the total poor function indicators for each model; and (2) estimating predicted probabilities of poor function at diagnosis. Agreement was evaluated using Fleiss' κ and Spearman's correlation. Associations between proxy measures and: (1) laparoscopic versus open surgery; (2) chemotherapy versus none; (3) 5-fluorouracil (5FU)+oxaliplatin (FOLFOX) versus 5FU monotherapy; and (4) 1-year mortality were estimated using log-binomial regression, controlling for age, sex, stage, and comorbidity. Survival estimates were stratified by functional group, age, and comorbidity. RESULTS: Among 29,687 eligible colon cancer patients, 67% were 75+ years and 45% had stage III disease. Concordance across the poor function indicator counts was moderate (κ: 0.64) and correlation of predicted probability measures varied (ρ: 0.21-0.74). Worse function was associated with lower chemotherapy and FOLFOX receipt, and higher 1-year mortality. Within age and comorbidity strata, poor function remained associated with mortality. CONCLUSIONS: While agreement varied across the claims-based proxy measures, each demonstrated anticipated associations with treatment receipt and mortality independent of comorbidity. Claims-based comparative effectiveness studies in older populations should consider applying one of these models to improve confounding control.

Diabetic ketoacidosis in patients with type 2 diabetes treated with sodium glucose co-transporter 2 inhibitors versus other antihyperglycemic agents: An observational study of four US administrative claims databases.

PURPOSE: To compare the incidence of diabetic ketoacidosis (DKA) among patients with type 2 diabetes mellitus (T2DM) who were new users of sodium glucose co-transporter 2 inhibitors (SGLT2i) versus other classes of antihyperglycemic agents (AHAs). METHODS: Patients were identified from four large US claims databases using broad (all T2DM patients) and narrow (intended to exclude patients with type 1 diabetes or secondary diabetes misclassified as T2DM) definitions of T2DM. New users of SGLT2i and seven groups of comparator AHAs were matched (1:1) on exposure propensity scores to adjust for imbalances in baseline covariates. Cox proportional hazards regression models, conditioned on propensity score-matched pairs, were used to estimate hazard ratios (HRs) of DKA for new users of SGLT2i versus other AHAs. When I2 <40%, a combined HR across the four databases was estimated. RESULTS: Using the broad definition of T2DM, new users of SGLT2i had an increased risk of DKA versus sulfonylureas (HR [95% CI]: 1.53 [1.31-1.79]), DPP-4i (1.28 [1.11-1.47]), GLP-1 receptor agonists (1.34 [1.12-1.60]), metformin (1.31 [1.11-1.54]), and insulinotropic AHAs (1.38 [1.15-1.66]). Using the narrow definition of T2DM, new users of SGLT2i had an increased risk of DKA versus sulfonylureas (1.43 [1.01-2.01]). New users of SGLT2i had a lower risk of DKA versus insulin and a similar risk as thiazolidinediones, regardless of T2DM definition. CONCLUSIONS: Increased risk of DKA was observed for new users of SGLT2i versus several non-SGLT2i AHAs when T2DM was defined broadly. When T2DM was defined narrowly to exclude possible misclassified patients, an increased risk of DKA with SGLT2i was observed compared with sulfonylureas.

Identification of cytokine release syndrome and indicators of severity in retrospective databases among patients receiving immunotherapy.

Cytokine release syndrome (CRS) can occur following cancer immunotherapies, but is most often mild and of limited duration. International Classification of Diseases (ICD)-10 codes allowing identification of CRS were introduced in 2020 but may be underutilized. We evaluated the performance of a published claims-based algorithm to detect CRS (any grade) and high-grade CRS (HG, grades 2-5), as well as identified indicators of HG CRS in retrospective data. Adults with low-grade and HG CRS during an encounter coinciding with administrations of blinatumomab or chimeric antigen receptor-T therapy were identified in three types of retrospective databases (hospital chargemaster data, electronic health records, and administrative claims). The algorithm's sensitivity in detecting any CRS and HG CRS was reported. A least absolute shrinkage and selection operator (LASSO) regression model was developed to identify indicators of HG CRS. Performance of the model was evaluated using area under the curve (AUC). The sensitivity of the algorithm to detect any grade CRS ranged between 77%-100% and between 8%-80% for HG CRS, depending on the type of database. The LASSO model identified hypotension, positive pressure (including mechanical ventilation), tocilizumab, and vasopressors as indicators of HG CRS. AUC varied between 60% and 75%. The algorithm accurately detected any grade CRS for over three-quarters of instances, but was not as reliable for HG CRS. Results varied based on database attributes. Hypotension, vasopressors, positive pressure, and tocilizumab were associated with HG CRS and may be methodologically helpful signals of CRS severity in retrospective data.

Update on prevalence of diagnosed systemic lupus erythematosus (SLE) by major health insurance types in the US in 2016.

OBJECTIVE: To provide current estimates of the number of patients with prevalent systemic lupus erythematosus (SLE) by major health insurance types in the US and to describe patient characteristics. Four large US health insurance claims databases were analyzed to represent different types of insurance coverage, including private insurance, Medicaid, and Medicare Supplemental. RESULTS: Overall unadjusted SLE prevalence per 100,000 persons in the US ranged from 150.1 (private insurance) to 252.9 (Medicare Supplemental insurance). Extrapolating to the US civilian population in 2016, we estimated roughly 345,000 to 404,000 prevalent SLE patients with private/Medicare insurance and 99,000 prevalent SLE patients with Medicaid insurance. Comorbidities, including renal failure/dialysis were commonly observed across multiple organ systems in SLE patients (8.4-21.1%). We estimated a larger number of prevalent SLE cases in the US civilian population than previous reports and observed extensive disease burden based on a 1-year cross-sectional analysis.

Characteristics and Outcomes of Over 300,000 Patients with COVID-19 and History of Cancer in the United States and Spain.

BACKGROUND: We described the demographics, cancer subtypes, comorbidities, and outcomes of patients with a history of cancer and coronavirus disease 2019 (COVID-19). Second, we compared patients hospitalized with COVID-19 to patients diagnosed with COVID-19 and patients hospitalized with influenza. METHODS: We conducted a cohort study using eight routinely collected health care databases from Spain and the United States, standardized to the Observational Medical Outcome Partnership common data model. Three cohorts of patients with a history of cancer were included: (i) diagnosed with COVID-19, (ii) hospitalized with COVID-19, and (iii) hospitalized with influenza in 2017 to 2018. Patients were followed from index date to 30 days or death. We reported demographics, cancer subtypes, comorbidities, and 30-day outcomes. RESULTS: We included 366,050 and 119,597 patients diagnosed and hospitalized with COVID-19, respectively. Prostate and breast cancers were the most frequent cancers (range: 5%-18% and 1%-14% in the diagnosed cohort, respectively). Hematologic malignancies were also frequent, with non-Hodgkin's lymphoma being among the five most common cancer subtypes in the diagnosed cohort. Overall, patients were aged above 65 years and had multiple comorbidities. Occurrence of death ranged from 2% to 14% and from 6% to 26% in the diagnosed and hospitalized COVID-19 cohorts, respectively. Patients hospitalized with influenza (n = 67,743) had a similar distribution of cancer subtypes, sex, age, and comorbidities but lower occurrence of adverse events. CONCLUSIONS: Patients with a history of cancer and COVID-19 had multiple comorbidities and a high occurrence of COVID-19-related events. Hematologic malignancies were frequent. IMPACT: This study provides epidemiologic characteristics that can inform clinical care and etiologic studies.

Acute pancreatitis risk in type 2 diabetes patients treated with canagliflozin versus other antihyperglycemic agents: an observational claims database study.

Objective: Observational evidence suggests that patients with type 2 diabetes mellitus (T2DM) are at increased risk for acute pancreatitis (AP) versus those without T2DM. A small number of AP events were reported in clinical trials of the sodium glucose co-transporter 2 inhibitor canagliflozin, though no imbalances were observed between treatment groups. This observational study evaluated risk of AP among new users of canagliflozin compared with new users of six classes of other antihyperglycemic agents (AHAs).Methods: Three US claims databases were analyzed based on a prespecified protocol approved by the European Medicines Agency. Propensity score adjustment controlled for imbalances in baseline covariates. Cox regression models estimated the hazard ratio of AP with canagliflozin compared with other AHAs using on-treatment (primary) and intent-to-treat approaches. Sensitivity analyses assessed robustness of findings.Results: Across the three databases, there were between 12,023-80,986 new users of canagliflozin; the unadjusted incidence rates of AP (per 1000 person-years) were between 1.5-2.2 for canagliflozin and 1.1-6.6 for other AHAs. The risk of AP was generally similar for new users of canagliflozin compared with new users of glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors, sulfonylureas, thiazolidinediones, insulin, and other AHAs, with no consistent between-treatment differences observed across databases. Intent-to-treat and sensitivity analysis findings were qualitatively consistent with on-treatment findings.Conclusions: In this large observational study, incidence rates of AP in patients with T2DM treated with canagliflozin or other AHAs were generally similar, with no evidence suggesting that canagliflozin is associated with increased risk of AP compared with other AHAs.

Risk of hydroxychloroquine alone and in combination with azithromycin in the treatment of rheumatoid arthritis: a multinational, retrospective study.

BACKGROUND: Hydroxychloroquine, a drug commonly used in the treatment of rheumatoid arthritis, has received much negative publicity for adverse events associated with its authorisation for emergency use to treat patients with COVID-19 pneumonia. We studied the safety of hydroxychloroquine, alone and in combination with azithromycin, to determine the risk associated with its use in routine care in patients with rheumatoid arthritis. METHODS: In this multinational, retrospective study, new user cohort studies in patients with rheumatoid arthritis aged 18 years or older and initiating hydroxychloroquine were compared with those initiating sulfasalazine and followed up over 30 days, with 16 severe adverse events studied. Self-controlled case series were done to further establish safety in wider populations, and included all users of hydroxychloroquine regardless of rheumatoid arthritis status or indication. Separately, severe adverse events associated with hydroxychloroquine plus azithromycin (compared with hydroxychloroquine plus amoxicillin) were studied. Data comprised 14 sources of claims data or electronic medical records from Germany, Japan, the Netherlands, Spain, the UK, and the USA. Propensity score stratification and calibration using negative control outcomes were used to address confounding. Cox models were fitted to estimate calibrated hazard ratios (HRs) according to drug use. Estimates were pooled where the I 2 value was less than 0·4. FINDINGS: The study included 956 374 users of hydroxychloroquine, 310 350 users of sulfasalazine, 323 122 users of hydroxychloroquine plus azithromycin, and 351 956 users of hydroxychloroquine plus amoxicillin. No excess risk of severe adverse events was identified when 30-day hydroxychloroquine and sulfasalazine use were compared. Self-controlled case series confirmed these findings. However, long-term use of hydroxychloroquine appeared to be associated with increased cardiovascular mortality (calibrated HR 1·65 [95% CI 1·12-2·44]). Addition of azithromycin appeared to be associated with an increased risk of 30-day cardiovascular mortality (calibrated HR 2·19 [95% CI 1·22-3·95]), chest pain or angina (1·15 [1·05-1·26]), and heart failure (1·22 [1·02-1·45]). INTERPRETATION: Hydroxychloroquine treatment appears to have no increased risk in the short term among patients with rheumatoid arthritis, but in the long term it appears to be associated with excess cardiovascular mortality. The addition of azithromycin increases the risk of heart failure and cardiovascular mortality even in the short term. We call for careful consideration of the benefit-risk trade-off when counselling those on hydroxychloroquine treatment. FUNDING: National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, NIHR Senior Research Fellowship programme, US National Institutes of Health, US Department of Veterans Affairs, Janssen Research and Development, IQVIA, Korea Health Industry Development Institute through the Ministry of Health and Welfare Republic of Korea, Versus Arthritis, UK Medical Research Council Doctoral Training Partnership, Foundation Alfonso Martin Escudero, Innovation Fund Denmark, Novo Nordisk Foundation, Singapore Ministry of Health's National Medical Research Council Open Fund Large Collaborative Grant, VINCI, Innovative Medicines Initiative 2 Joint Undertaking, EU's Horizon 2020 research and innovation programme, and European Federation of Pharmaceutical Industries and Associations.

Rabies in bats from Alabama.

Data on rabies virus infection in bats that were submitted to the Alabama Department of Public Health from 1995-2005 were analyzed. Demographic factors, such as species and sex, and temporal aspects, such as yearly and monthly trends, were investigated. Thirteen species of bats were submitted, and of those, individuals from seven species were rabid; prevalence was highest in Lasiurus borealis and Pipistrellus subflavus and lowest in Eptesicus fuscus and Nycticeius humeralis. There was no difference in prevalence of rabies between sexes or years. Statistically, more rabid bats were submitted in August, September, and November; and fewer were submitted in March, June, and July. Results were similar to those from other regions of North America; these data from Alabama can help to present a more complete view of rabies in bats in North America.

Publication of comparative effectiveness research has not increased in high-impact medical journals, 2004-2013.

OBJECTIVE: To explore the impact of increasing interest and investment in patient-centered research, this study sought to describe patterns of comparative effectiveness research (CER) and patient-reported outcomes (PROs) in pharmacologic intervention studies published in widely read medical journals from 2004-2013. DESIGN AND SETTING: We identified 2335 articles published in five widely read medical journals from 2004-2013 with ≥1 intervention meeting the US Food and Drug Administration's definitions for a drug, biologic, or vaccine. Six trained reviewers extracted characteristics from a 20% random sample of articles (468 studies). We calculated the proportion of studies with CER and PROs. Trends were summarized using locally-weighted means and 95% confidence intervals. RESULTS: Of the 468 sampled studies, 30% used CER designs and 33% assessed PROs. The proportion of studies using CER designs did not meaningfully increase over the study period. However, we observed an increase in the use of PROs. CONCLUSIONS: Among pharmacological intervention studies published in widely read medical journals from 2004-2013, we identified no increase in CER. Randomized, placebo-controlled trials continue to be the dominant study design for assessing pharmacologic interventions. Increasing trends in PRO use may indicate greater acceptance of these outcomes as evidence for clinical benefit.

Methodologic Issues When Estimating Risks in Pharmacoepidemiology.

Risk is an important parameter to describe the occurrence of health outcomes over time. However, many outcomes of interest in healthcare settings, such as disease incidence, treatment initiation, and cause-specific mortality, may be precluded from occurring by other events, often referred to as competing events. Here, we review straightforward approaches to estimate risk in the presence of competing events. We illustrate the application of these methods using timely examples in pharmacoepidemiologic research and compare results to those obtained using analytic simplifications commonly used to handle competing events. These examples demonstrate how the analytic methods used to account for competing events affect the interpretation of results from pharmacoepidemiologic studies.

Applying the Social Ecological Model to Creating Asthma-Friendly Schools in Louisiana.

BACKGROUND: In 2010, the Louisiana Asthma Management and Prevention Program (LAMP) implemented the Asthma-Friendly Schools Initiative in high-risk Louisiana populations. The social ecological model (SEM) was used as a framework for an asthma program implemented in 70 state K-12 public schools over 2 years. METHODS: Activities included a needs assessment, identification of students with asthma, individualized asthma action plans (AAP), staff trainings, environmental quality improvement, and school system policy changes to address the asthma burden. RESULTS: There were 522 new or existing asthma cases recognized. Asthma knowledge/awareness was measurably improved among school personnel. School indoor air quality was improved across all locations. School-level policies were adopted that improved AAP collection, compliance to bus-idling restrictions, and asthma medication self-carry. CONCLUSIONS: The SEM framework can be used for school-based programs to address successfully and improve asthma-related issues from the individual through policy levels.

Roles of the state asthma program in implementing multicomponent, school-based asthma interventions.

BACKGROUND: Asthma is a leading chronic childhood disease in the United States and a major contributor to school absenteeism. Evidence suggests that multicomponent, school-based asthma interventions are a strategic way to address asthma among school-aged children. The Centers for Disease Control and Prevention (CDC) encourages the 36 health departments (34 states, District of Columbia, and Puerto Rico) in the National Asthma Control Program (NACP) to implement multicomponent, school-based asthma interventions on a larger scale. METHODS: To gain a better understanding of replicable best practices for state-coordinated asthma interventions in schools, an NACP evaluation team conducted evaluability assessments of promising interventions run by state asthma programs in Louisiana, Indiana, and Utah. RESULTS: The team found that state asthma programs play a critical role in implementing school-based asthma interventions due to their ability to (1) use statewide surveillance data to identify asthma trends and address disparities; (2) facilitate connections between schools, school systems, and school-related community stakeholders; (3) form state-level connections; (4) translate policies into action; (5) provide resources and public health practice information to schools and school systems; (6) monitor and evaluate implementation. CONCLUSIONS: This article presents evaluability assessment findings and illustrates state roles using examples from the 3 participating state asthma programs.

An examination of spatial concentrations of sex exchange and sex exchange norms among drug users in Baltimore, Maryland.

Baltimore, Maryland consistently ranks highest nationally in rates of sexually transmitted diseases and HIV infection. Prior studies have identified geographic areas where STI and HIV infection in the city is most prevalent. It is well established that sex exchange behavior is associated with HIV and STIs, yet it is not well understood how sex exchangers are spatially distributed within the high-risk areas. We sought to examine the spatial distribution of individuals who report sex exchange compared to those who do not exchange. Additionally we examined the spatial context of perceived norms about sex exchange. Data for the study came from a baseline sample of predominately injection drug users (n=842). Of these, 21% reported sex exchange in the prior 90 days. All valid baseline residential addresses of participants living within Baltimore city boundaries were geocoded. The Multi-Distance Spatial Cluster Analysis (Ripley's K-function) was used to separately calculate the K-functions for the addresses of participants reporting sex exchange or non-sex exchange, relative to the recruited population. Evidence of spatial clustering of sex exchangers was observed and norms aligned with these clusters. Of particular interest was the high density of sex exchangers in one specific housing complex of East Baltimore, which happens to be the oldest in Baltimore. These findings can inform targeted efforts for screening and testing for HIV and STIs and placement of both individual and structural level interventions that focus on increasing access to risk reduction materials and changing norms about risk behaviors.

Social network characteristics and heavy episodic drinking among women at risk for HIV/sexually transmitted infections.

OBJECTIVE: Social networks can either negatively or positively influence a variety of behaviors, including alcohol use. This study examined social network characteristics that are risk factors for and protective factors against heavy episodic drinking among a sample of women at risk for HIV/sexually transmitted infections. METHOD: This was a cross-sectional study using baseline data from 567 impoverished women participating in an HIV prevention study in Baltimore, MD. Data were collected through face-to-face interviews at a community-based research clinic. Heavy episodic drinking was defined as six or more drinks per drinking episode on at least a weekly basis. We examined network characteristics, including structure and function and their association with heavy episodic drinking. Multivariate logistic regression was used, adjusting for individual-level factors, such as drug use, demographics, and depression. RESULTS: Approximately 21% of the sample engaged in heavy episodic drinking at least weekly. Controlling for individual-level factors, women who engaged in heavy episodic drinking had fewer social network members (a) who were in drug treatment, adjusted odds ratio (AOR) = 0.65, 95% CI [0.49, 0.88]; (b) who were employed, AOR = 0.89, 95% CI [0.79, 0.99]; and (c) with whom the participant socialized, AOR = 0.74, 95% CI [0.63, 0.96]. Women who engaged in heavy episodic drinking had a significantly higher number of social network members with whom they drank alcohol, AOR = 1.71, 95% CI [1.43, 2.03]. CONCLUSIONS: Social network characteristics are both protective and risk factors for heavy episodic drinking among women. Interpersonal interventions, such as peer education, may be a useful strategy to decrease heavy episodic drinking and its subsequent outcomes among women.