Hip muscle strength and protection against structural worsening and poor function and disability outcomes in knee osteoarthritis.

OBJECTIVE: Examine associations of hip abductor strength with (1) cartilage damage worsening in the tibiofemoral and patellofemoral compartments 2 years later, and (2) poor function and disability outcomes 5 years later. METHODS: Participants had knee osteoarthritis (K/L ≥ 2) in at least one knee. Hip abductor strength was measured using Biodex Dynamometry. Participants underwent 3.0T MRI of both knees at baseline and 2 years later. Baseline-to-2-year cartilage damage progression, defined as any worsening of WORMS cartilage damage score, was assessed at each tibiofemoral and patellofemoral surface. LLFDI (Late-Life Function and Disability Instrument) and Chair-Stand-Rate were recorded at baseline and 5-year follow-up; outcomes analyzed using quintiles. Poor outcomes were defined as remaining in the same low-function quintiles or being in a worse quintile at 5-year follow-up. We analyzed associations of baseline hip abductor strength with cartilage damage worsening and function and disability outcomes using multivariable log-binomial models. RESULTS: 275 knees from 164 persons [age = 63.7 (SD = 9.8) years, 79.3% women] comprised the structural outcome sample, and 187 persons [age = 64.2 (9.7), 78.6% women] the function and disability outcomes sample. Greater baseline hip abductor strength was associated with reduced risks of baseline-to-2-year medial patellofemoral and lateral tibiofemoral cartilage damage worsening [adjusted relative risks (RRs) range: 0.80-0.83) and with reduced risks of baseline-to-5-year poor outcomes for Chair-Stand-Rate and LLFDI Basic Lower-Extremity Function and Disability Limitation (adjusted RRs range: 0.91-0.94). CONCLUSION: Findings support a beneficial role of hip abductor strength for disease modification and for function and disability outcomes, and as a potential therapeutic target in managing knee osteoarthritis.

Implementation and dissemination of an African American popular opinion model to improve lupus awareness: an academic-community partnership.

OBJECTIVE: Lupus is a chronic, autoimmune disease that disproportionately affects African Americans. We adapted the Centers for Disease Control and Prevention's Popular Opinion Leader model to implement an intervention tailored for African American individuals that leverages an academic-community partnership and community-based social networks to disseminate culturally appropriate lupus education. METHODS: Academic rheumatologists, social scientists, and researchers in Boston, MA and Chicago, IL partnered with local lupus support groups, community organizations, and churches in neighborhoods with higher proportions of African Americans to develop curriculum and recruit community leaders with and without lupus (Popular Opinion Leaders; POLs). POLs attended four training sessions focused on lupus education, strategies to educate others, and a review of research methods. POLs disseminated information through their social networks and recorded their impact, which was mapped using a geographic information system framework. RESULTS: We trained 18 POLs in greater Boston and 19 in greater Chicago: 97% were African American, 97% were female; and the mean age was 57 years. Fifty-nine percent of Boston POLs and 68% of Chicago POLs had lupus. POLs at both sites engaged members of their social networks and communities in conversations about lupus, health disparities, and the importance of care. Boston POLs documented 97 encounters with 547 community members reached. Chicago POLs documented 124 encounters with 4083 community members reached. CONCLUSIONS: An adapted, community-based POL model can be used to disseminate lupus education and increase awareness in African American communities. Further research is needed to determine the degree to which this may begin to reduce disparities in access to care and outcomes.

Knee tissue lesions and prediction of incident knee osteoarthritis over 7 years in a cohort of persons at higher risk.

OBJECTIVE: Among high risk individuals, whether knee lesions in tissues involved in osteoarthritis (OA) can improve prediction of knee OA is unclear. We hypothesized that models predicting (1) incident osteophytes and (2) incident osteophytes and joint space narrowing can be improved by including symptoms or function, and further improved by lesion status. DESIGN: In Osteoarthritis Initiative (OAI) participants with normal knee X-rays, we assessed cartilage damage, bone marrow lesions (BMLs), and menisci. Cox proportional hazards models were used to develop risk prediction models for risk of each outcome. Nested models (increasingly larger baseline covariable sets) were compared using likelihood ratio tests and Schwarz Bayesian Information Criterion (SBC). Model discrimination used receiver operating characteristic (ROC) curves and area under the curve (AUC). RESULTS: In 841 participants [age 59.6, body mass index (BMI) 26.7, 55.9% women] over up to 7 years follow-up, each larger set improved prediction (+hand OA, injury, surgery, activities; +symptoms/function). Prediction was further improved by including cartilage damage both compartments, BMLs both compartments, meniscal tear, meniscal extrusion, sum of lesion types, number of subregions with cartilage damage, number of subregions with BMLs, and (concurrently) subregion number with cartilage damage, subregion number with BMLs, and meniscal tear. AUCs were ≥0.80 for both outcomes for number of subregions with cartilage damage and the combined model. CONCLUSIONS: Among persons at higher risk for knee OA with normal X-rays, MRI tissue lesions improved prediction of mild as well as moderate disease. These findings support that disease onset is likely occurring during the "high-risk" period and encourage a reorientation of approach.

Association of baseline knee sagittal dynamic joint stiffness during gait and 2-year patellofemoral cartilage damage worsening in knee osteoarthritis.

OBJECTIVE: Knee sagittal dynamic joint stiffness (DJS) describes the biomechanical interaction between change in external knee flexion moment and flexion angular excursion during gait. In theory, greater DJS may particularly stress the patellofemoral (PF) compartment and thereby contribute to PF osteoarthritis (OA) worsening. We hypothesized that greater baseline knee sagittal DJS is associated with PF cartilage damage worsening 2 years later. METHODS: Participants all had OA in at least one knee. Knee kinematics and kinetics during gait were recorded using motion capture systems and force plates. Knee sagittal DJS was computed as the slope of the linear regression line for knee flexion moments vs angles during the loading response phase. Knee magnetic resonance imaging (MRI) scans were obtained at baseline and 2 years later. We assessed the association between baseline DJS and baseline-to-2-year PF cartilage damage worsening using logistic regression with generalized estimating equations (GEE). RESULTS: Our sample had 391 knees (204 persons): mean age 64.2 years (SD 10.0); body mass index (BMI) 28.4 kg/m2 (5.7); 76.5% women. Baseline knee sagittal DJS was associated with baseline-to-2-year cartilage damage worsening in the lateral (OR = 5.35, 95% CI: 2.37-12.05) and any PF (OR = 2.99, 95% CI: 1.27-7.04) compartment. Individual components of baseline DJS (i.e., change in knee moment or angle) were not associated with subsequent PF disease worsening. CONCLUSION: Capturing the concomitant effect of knee kinetics and kinematics during gait, knee sagittal DJS is a potentially modifiable risk factor for PF disease worsening.

CD4 cell count at initiation of ART, long-term likelihood of achieving CD4 >750 cells/mm3 and mortality risk.

OBJECTIVES: We sought to evaluate associations between CD4 at ART initiation (AI), achieving CD4 >750 cells/mm(3) (CD4 >750), long-term immunological recovery and survival. METHODS: This was a prospective observational cohort study. We analysed data from ART-naive patients seen in 1996-2012 and followed ≥3 years after AI. We used Kaplan-Meier (KM) methods and log-rank tests to compare time to achieving CD4 >750 by CD4 at AI (CD4-AI); and Cox regression models and generalized estimating equations to identify factors associated with achieving CD4 >750 and mortality risk. RESULTS: Of 1327 patients, followed for a median of 7.9 years, >85% received ART for ≥75% of follow-up time; 64 died. KM estimates evaluating likelihood of CD4 >750 during 5 years of follow-up, stratified by CD4-AI <50, 50-199, 200-349, 350-499 and 500-750, were 20%, 25%, 56%, 80% and 87%, respectively (log-rank P < 0.001). In adjusted models, CD4-AI ≥200 (versus CD4-AI <200) was associated with achievement of CD4 >750 [adjusted HR (aHR) = 4.77]. Blacks were less likely than whites to achieve CD4 >750 (33% versus 49%, aHR = 0.77). Mortality rates decreased with increasing CD4-AI (P = 0.004 across CD4 strata for AIDS causes and P = 0.009 for non-AIDS death causes). Among decedents with CD4-AI ≥50, 56% of deaths were due to non-AIDS causes. CONCLUSIONS: Higher CD4-AI resulted in greater long-term CD4 gains, likelihood of achieving CD4 >750, longer survival and decreased mortality regardless of cause. Over 80% of persons with CD4-AI ≥350 achieved CD4 >750 by 4 years while 75% of persons with CD4-AI <200 did not. These data confirm the hazards of delayed AI and support early AI.

Fatigue, patient reported outcomes, and objective measurement of physical activity in systemic lupus erythematosus.

OBJECTIVE: Fatigue is a common symptom in systemic lupus erythematosus (SLE), and engaging in physical activity may reduce fatigue. We aimed to characterize relationships between fatigue, other health status measures assessed with the Patient Reported Outcomes Measurement Information System (PROMIS) instruments, and accelerometer-based physical activity measurements in patients with SLE. The internal consistency of each PROMIS measure in our SLE sample was also evaluated. METHODS: This cross-sectional study analyzed 123 adults with SLE. The primary fatigue outcome was Fatigue Severity Scale score. Secondary outcomes were PROMIS standardized T-scores in seven health status domains. Accelerometers were worn for seven days, and mean daily minutes of light, moderate/vigorous, and bouted (10 minutes) moderate/vigorous physical activity were estimated. Cronbach's alpha was determined for each PROMIS measure to assess internal consistency. Relationships between Fatigue Severity Scale, PROMIS, and physical activity were summarized with Spearman partial correlation coefficients (r), adjusted for average daily accelerometer wear time. RESULTS: Mean Fatigue Severity Scale score (4.3, SD 1.6) was consistent with clinically relevant levels of fatigue. Greater daily and bouted moderate/vigorous physical activity minutes correlated with lower Mean Fatigue Severity Scale score (r = -0.20, p = 0.03 and r = -0.30, p = 0.0007, respectively). For PROMIS, bouted moderate/vigorous physical activity minutes correlated with less fatigue (r = -0.20, p = 0.03). PROMIS internal consistency was excellent, with Cronbach's alpha > 0.90 for each domain. Mean PROMIS T-scores for fatigue, pain interference, anxiety, sleep disturbance, sleep-related impairment, and physical function were worse than reported for the general US population. More moderate/vigorous physical activity minutes were associated with less pain interference (r = -0.22, p = 0.01). Both light physical activity and moderate/vigorous physical activity minutes correlated with better physical function (r = 0.19, p = 0.04 and r = 0.25, p = 0.006, respectively). CONCLUSION: More time spent in moderate/vigorous physical activity was associated with less fatigue (Fatigue Severity Scale and PROMIS), less pain interference, and better physical function (PROMIS). PROMIS had excellent internal consistency in our SLE sample, and six of seven PROMIS measures indicated poorer average health status in SLE patients compared with the general US population.

External knee adduction and flexion moments during gait and medial tibiofemoral disease progression in knee osteoarthritis.

OBJECTIVE: Test the hypothesis that greater baseline peak external knee adduction moment (KAM), KAM impulse, and peak external knee flexion moment (KFM) during the stance phase of gait are associated with baseline-to-2-year medial tibiofemoral cartilage damage and bone marrow lesion progression, and cartilage thickness loss. METHODS: Participants all had knee OA in at least one knee. Baseline peak KAM, KAM impulse, and peak KFM (normalized to body weight and height) were captured and computed using a motion analysis system and six force plates. Participants underwent MRI of both knees at baseline and 2 years later. To assess the association between baseline moments and baseline-to-2-year semiquantitative cartilage damage and bone marrow lesion progression and quantitative cartilage thickness loss, we used logistic and linear regressions with generalized estimating equations (GEE), adjusting for gait speed, age, gender, disease severity, knee pain severity, and medication use. RESULTS: The sample consisted of 391 knees (204 persons): mean age 64.2 years (SD 10.0); BMI 28.4 kg/m(2) (5.7); 156 (76.5%) women. Greater baseline peak KAM and KAM impulse were each associated with worsening of medial bone marrow lesions, but not cartilage damage. Higher baseline KAM impulse was associated with 2-year medial cartilage thickness loss assessed both as % loss and as a threshold of loss, whereas peak KAM was related only to % loss. There was no relationship between baseline peak KFM and any medial disease progression outcome measures. CONCLUSION: Findings support targeting KAM parameters in an effort to delay medial OA disease progression.

Varus thrust and knee frontal plane dynamic motion in persons with knee osteoarthritis.

OBJECTIVE: Varus thrust visualized during walking is associated with a greater medial knee load and an increased risk of medial knee osteoarthritis (OA) progression. Little is known about how varus thrust presence determined by visual observation relates to quantitative gait kinematic data. We hypothesized that varus thrust presence is associated with greater knee frontal plane dynamic movement during the stance phase of gait. METHODS: Participants had knee OA in at least one knee. Trained examiners assessed participants for varus thrust presence during ambulation. Frontal plane knee motion during ambulation was captured using external passive reflective markers and an 8-camera motion analysis system. To examine the cross-sectional relationship between varus thrust and frontal plane knee motion, we used multivariable regression models with the quantitative motion measures as dependent variables and varus thrust (present/absent) as predictor; models were adjusted for age, gender, body mass index (BMI), gait speed, and knee static alignment. RESULTS: 236 persons [mean BMI: 28.5 kg/m(2) (standard deviation (SD) 5.5), mean age: 64.9 years (SD 10.4), 75.8% women] contributing 440 knees comprised the study sample. 82 knees (18.6%) had definite varus thrust. Knees with varus thrust had greater peak varus angle and greater peak varus angular velocity during stance than knees without varus thrust (mean differences 0.90° and 6.65°/s, respectively). These patterns remained significant after adjusting for age, gender, BMI, gait speed, and knee static alignment. CONCLUSION: Visualized varus thrust during walking was associated with a greater peak knee varus angular velocity and a greater peak knee varus angle during stance phase of gait.

Operational changes to the lupus intervention fatigue trial as a result of COVID-19: An update to the study protocol.

Background: The coronavirus disease 2019 (COVID-19) global pandemic drastically impacted the health system and the research community. As a result, research institutions and funding agencies recommended a moratorium on conducting in-person research and study enrollment until protocol changes to protect participant safety were approved and implemented. We detail the operational modifications made to the Lupus Intervention Fatigue Trial (LIFT) protocol and summarize how we met the varied challenges created by COVID-19. Methods: We evaluated study protocols and determined that scheduling, acquiring consent, in-person assessments and intervention baseline visits, patient reported outcomes, and data processing procedures needed modification. Results: Operational modifications were made to ensure study progress while adhering to COVID-19 restrictions. Major changes included electronic consent, remote baseline visits for those in the intervention, self-report outcome measures at home via emailed weblinks, and telemedicine physician assessment visits. The collection of safety labs presented the largest challenge since this required an in-person visit to a laboratory. The study team elected to delay this up to one month after the physician assessment. All follow-up visits were completed, and no participants withdrew from the study. Conclusion: LIFT was severely impacted by COVID-19. We provide insight into how our study protocol was modified without compromising the integrity of the primary and secondary outcomes of the study. The modifications utilized by the LIFT study resulted in efficiencies that will be included in a revised protocol and may serve as a useful example for other behavioral interventions to adapt their research studies.

Allergen-specific IgE as a biomarker of exposure plus sensitization in inner-city adolescents with asthma.

BACKGROUND: Relationships among allergen-specific IgE levels, allergen exposure and asthma severity are poorly understood since sensitization has previously been evaluated as a dichotomous, rather than continuous characteristic. METHODS: Five hundred and forty-six inner-city adolescents enrolled in the Asthma Control Evaluation study underwent exhaled nitric oxide (FE(NO)) measurement, lung function testing, and completion of a questionnaire. Allergen-specific IgE levels and blood eosinophils were quantified. Dust samples were collected from the participants' bedrooms for quantification of allergen concentrations. Participants were followed for 12 months and clinical outcomes were tracked. RESULTS: Among sensitized participants, allergen-specific IgE levels were correlated with the corresponding settled dust allergen levels for cockroach, dust mite, and mouse (r = 0.38, 0.34, 0.19, respectively; P < 0.0001 for cockroach and dust mite and P = 0.03 for mouse), but not cat (r = -0.02, P = 0.71). Higher cockroach-, mite-, mouse-, and cat-specific IgE levels were associated with higher FE(NO) concentrations, poorer lung function, and higher blood eosinophils. Higher cat, dust mite, and mouse allergen-specific IgE levels were also associated with an increasing risk of exacerbations or hospitalization. CONCLUSIONS: Allergen-specific IgE levels were correlated with allergen exposure among sensitized participants, except for cat. Allergen-specific IgE levels were also associated with more severe asthma across a range of clinical and biologic markers. Adjusting for exposure did not provide additional predictive value, suggesting that higher allergen-specific IgE levels may be indicative of both higher exposure and a greater degree of sensitization, which in turn may result in greater asthma severity.

KB001-A, a novel anti-inflammatory, found to be safe and well-tolerated in cystic fibrosis patients infected with Pseudomonas aeruginosa.

BACKGROUND: Chronic Pseudomonas aeruginosa (Pa) airways infection, exuberant local inflammation, and progressive lung function loss are hallmarks of cystic fibrosis (CF). KB001-A is an anti-PcrV PEGylated monoclonal antibody fragment to the Type III secretion system of Pa. This 16-week study evaluated KB001-A associated effect on time-to-need for antibiotics for worsening respiratory signs and symptoms, as well as safety, and treatment-associated changes in symptom scores, inflammatory markers, and spirometry. METHODS: This was a randomized, double-blind, placebo-controlled, repeat-dose study in CF subjects with Pa. Intravenous 10mg/kg KB001-A or placebo infusions were administered at baseline and weeks 2, 4, 8, and 16, with a 4-week follow-up. Sputum inflammatory markers were assessed in a sub-study. Time-to-need for antibiotics was compared between groups by Kaplan Meier analysis and Cox proportional hazards modeling adjusting for randomization strata. RESULTS: Of 182 subjects, 169 received at least one infusion of KB001-A (n=83) or placebo (n=86). KB001-A was generally safe and well-tolerated as compared to placebo, with no significant emergent adverse effects other than one serious adverse event of elevated hepatic enzymes of unclear etiology. Time to need for antibiotics did not differ between groups (HR: 1.00; 95% CI: 0.69, 1.45, p=0.995). A 3.2 increase in ppFEV1 from placebo favoring KB001-A was observed at week 16 (95% CI: 1.12, 5.30, p=0.003). Mean changes from baseline in log10 sputum neutrophil elastase (NE) had a non-significant decrease (-0.27, 95% CI: -0.58,0.04, p=0.084) while IL-8 concentrations at week 16 were significantly lower (-0.27, 95% CI: -0.55,0.00, p=0.048) among KB001-A subjects (n=16) relative to placebo (n=13). CONCLUSIONS: KB001-A was safe and well-tolerated and associated with a modest FEV1 benefit and reduction in select sputum inflammatory markers (IL-8). KB001-A was not associated with an increased time to need for antibiotics. The lack of efficacy seen with KB001-A may be due, in part, to the low levels of the type III secretion proteins previously reported in sputum of CF patients chronically infected with Pa.

Prognostic implications of proliferative activity and DNA aneuploidy in Astler-Coller Dukes stage C colonic adenocarcinomas.

Paraffin-embedded surgical specimens from 69 patients who underwent resections of otherwise untreated Dukes stage C adenocarcinoma of the colon were examined for proliferative activity, DNA aneuploidy, DNA index, and proportion of aneuploid cells by flow cytometry. Results were correlated to clinical characteristics of the patients and to overall survival times. DNA aneuploid tumors were identified in 60 cases (87%), diploid tumors in 9 cases (13%). The mean S-phase fraction for all cases was 17.6%, with a standard deviation (SD) of 7.8. In univariate statistical analysis, younger patient age, lower tumor proliferative activity, DNA index less than or equal to 1.2, and presence of only 1-4 lymph nodes with tumor involvement were found to be significant predictors of improved patient survival. In multivariate Cox regression analysis, low tumor proliferative activity, younger patient age, and location of the tumor in the right or transverse colon were found to be significant independent predictors of increased patient survival. When tumor proliferative activity was stratified into statistically defined subgroups, patients with tumors of low proliferative activity (S-phase less than mean - 0.5 SD) had significantly longer survival than patients with tumors of moderate proliferative activity (S-phase value greater than mean - 0.5 SD and less than mean +0.5 SD) or high proliferative activity (S-phase greater than mean +0.5 SD). These results suggest that tumor proliferative activity in Dukes C colon carcinoma may be an important biological factor in determining patient prognosis.

Sequential clinical and immunologic abnormalities in hemophiliacs.

We examined 35 patients with hemophilia to determine if there was an association between impaired cell-mediated immunity and the amount of factor concentrate use. There was a significant negative relationship between the logarithm of the helper-suppressor ratio and the logarithm of concentrate use determined over the previous one year, five years, and total lifetime. Similarly, the presence of splenomegaly was significantly associated with the logarithm of concentrate use for each time interval. Hypergammaglobulinemia, anergy, and lymphadenopathy were present in a high proportion of patients. Repeated study of 30 of these patients at eight to 14 months showed no significant changes in their T-cell subsets. At follow-up, 16 patients had lymphadenopathy with or without splenomegaly and four had splenomegaly alone. No significant associations between concentrate use during the study period and changes in T-cell subsets or clinical condition were found.

Low testosterone and sexual symptoms in men with acute coronary syndrome can be used to predict major adverse cardiovascular events during long-term follow-up.

Low total testosterone (TT) and sexual symptoms are common among men with coronary artery disease, however its impact on major adverse cardiovascular events (MACE) is still debatable. We investigated whether low TT and coexisting sexual symptoms in men with acute coronary syndrome (ACS) can be used to predict the incidence of MACE. In the prospective study 120 consecutive men (mean age 58 ± 9 years; diabetes 27%; current smokers 58%; left ventricular ejection fraction 50 ± 10%) with ACS were included. The group of men with the presence of three sexual symptoms (decreased frequency of morning erections, a lack of sexual thoughts and erectile dysfunction) and with TT serum concentration <3.2 ng/mL was distinguished. All of the patients had their prognosis assessed according to the Global Registry of Acute Coronary Events (GRACE Score 2.0). Primary composite endpoint - MACE (recurrent ischaemia, non-fatal myocardial infarction, stroke and death) and secondary endpoint - in stent restenosis (ISR) were registered during the 18.3 month follow-up period. The mean TT level in the entire group was 3.7 ± 0.5 ng/mL. Low TT was diagnosed in 63 (52.5%) men. Both low TT and sexual symptoms were diagnosed in 57 (47%) participants. During the follow-up, 29 (24.2%) participants experienced MACE, 20 (16.6%) men ISR. In the Cox proportional hazards regression, high risk of death on the GRACE score (HR 3.16; 95% CI: 1.5-6.6; p = 0.002), the presence of low TT and sexual symptoms (HR 2.75; 95% CI: 1.26-6.04; p = 0.02) independently predicted an incidence of a MACE (p = 0.006). For the secondary endpoint only low TT and sexual symptoms (HR 2.68; 95% CI: 1.03-6.94; p = 0.034) were independent covariates which predicted IRS. Low TT which coexists with sexual symptoms in males with ACS can be used to predict MACE, especially IRS independently of classic cardiovascular risk factors.

Two quick estimates of the HIV prevalence in homosexual men in Los Angeles, New York and San Francisco. The Multicenter AIDS Cohort Study.

Two rough methods are given to estimate the combined HIV prevalence in Los Angeles, New York and San Francisco in homosexual men. Both methods are related to the back calculation technique, and use AIDS surveillance data and information obtained from the Multicenter AIDS Cohort Study. Both methods suggest that the combined HIV prevalence is approximately 100,000, with a possible range of 80,000-140,000.

Evidence that anoreceptive intercourse with ejaculate exposure is associated with rapid CD4 cell loss.

OBJECTIVE: To determine whether ejaculate exposure through anoreceptive intercourse is associated with rapid CD4 cell loss. DESIGN: Self-reported behavioral, demographic data and blood samples were gathered longitudinally at ten semiannual visits from individuals participating in the Multicenter AIDS Cohort Study (MACS). PATIENTS/PARTICIPANTS: A group of 937 HIV-seropositive men who were continuously followed for four to ten semiannual visits. OUTCOME MEASURES: A loss of 10% or more in CD4 cells between the first two of any three consecutive semiannual visits that was followed by a 10% or greater loss between the second and third visits. RESULTS: A period of rapid CD4 cell loss over three semiannual visits occurred in 389 of the 937 (42%) HIV-seropositive men studied. Men who reported one or more anoreceptive intercourse partners with whom they were exposed to ejaculate (RAI-E) during the 12 months immediately preceding their visits were more than twice as likely to show this rapid CD4 cell loss compared with men with no such partners. CONCLUSIONS: The association between RAI-E partnerships and rapid CD4 cell loss suggests factors associated with ejaculate exposure (e.g., sexually transmitted diseases) may hasten the clinical progression of HIV disease. It is suggested that infectious diseases, which are known to be associated with ejaculate exposure, may be the causal factor underlying the association between RAI-E partnerships and rapid CD4 cell loss in these men, although the presence of these diseases was not ascertained in these data. HIV-infected individuals should be cautioned against unprotected anoreceptive intercourse.

Racial differences in rate of CD4 decline in HIV-1-infected homosexual men.

OBJECTIVE: To determine whether racial differences exist in the rate of CD4 lymphocyte decline in HIV-1-infected homosexual men. DESIGN: Prospective cohort study. STUDY POPULATION: Non-Hispanic white (n = 321) and black (n = 102) HIV-1-seropositive homosexual and bisexual men were recruited from the Baltimore/Washington, DC metropolitan areas between 1984-1985 and 1987-1990, and evaluated semiannually. MAIN MEASUREMENTS: Changes in CD4 lymphocyte count and CD4 percentage over time were analysed using linear regression methods for the 271 white and 69 black participants who had at least four semiannual CD4 lymphocyte measurements. RESULTS: Rate of decline in CD4 lymphocyte count over 6 months was much slower among black than white seroprevalent men at all levels of baseline CD4 count (baseline 201-400 x 10(6)/l: + 0.24 versus -17.7 x 10(6)/l; 401-600 x 10(6)/l: -11.3 versus -23.9 x 10(6)/l; 601-800 x 10(6)/l: -15.1 versus -35.2 x 10(6)/l; > 800 x 10(6)/l: -4.3 versus -42.7 x 10(6)/l for black versus white, respectively), although this was only statistically significant for the lowest and highest strata of baseline CD4 count. These racial differences persisted after adjustment for recruitment period (1984-1985 or 1987-1990), follow-up duration, age and zidovudine therapy or Pneumocystis carinii pneumonia prophylaxis. Similar findings were observed among the 70 white and 11 black seroconverters. Black participants were also less likely than a subgroup of white participants matched on baseline CD4 lymphocyte count to be HIV-1 p24 antigen-positive. However, after acid dissociation of samples initially p24 antigen-negative, there were no significant differences in the prevalence of p24 antigenemia at enrollment or after 1 year of follow-up. CONCLUSIONS: This analysis suggests a more gradual decline in CD4 lymphocyte count among black than white Americans. The clinical significance of and reasons for this are unclear, but the lower prevalence of p24 antigenemia due to immune complexing among black Americans suggests that racial differences in the immune response to HIV may exist. Additional studies are needed to validate these findings in a larger cohort of non-whites, and to assess their relationship with other measures of cell-mediated immune function.

Dependence of the hazard of AIDS on markers.

OBJECTIVE: To investigate the dependence of the hazard of symptomatic AIDS on various markers using a non-parametric method. The markers we consider are measures of time (time since infection and calendar date), measures of immune function (numbers and percentage of CD4 T cells) and serological activation markers (neopterin and beta 2-microglobulin). METHODS: We adapted a non-parametric statistical method to estimate the hazard of AIDS. We considered both univariate analyses, in which each marker was considered separately and bivariate analyses of pairs of markers. CONCLUSIONS: Using data from 356 seroconverters from the Multicenter AIDS Cohort Study, we found that in the univariate analyses the hazard of AIDS is dependent on all markers, with the strongest dependence for CD4 count and CD4 percentage. In the bivariate analyses we found that the time since infection is of little importance in determining the hazard of AIDS if the CD4 count or percentage are known, and is of minor additional value if one of the serological markers is known. In contrast, we found that both beta 2-microglobulin and neopterin do add some additional information to the hazard of AIDS if CD4 count or CD4 percentage are known.

Stressful life events and symptom onset in HIV infection.

OBJECTIVE: The authors' goal is to provide basic epidemiologic data on the issue of reactivity to stress and HIV symptom onset by studying the relationship between a broad set of naturally occurring stressor events and HIV natural history in a large longitudinal community sample of HIV-seropositive homosexual men. METHOD: Subjects were recruited from a cohort of 1,011 homosexual men enrolled in the Chicago site of the Multicenter AIDS Cohort Study who also participated in the Coping and Change Study. The men were given self-administered questionnaires assessing behavioral, psychological, and psychosocial variables. Relationships between reports of stressful life events and longitudinal biomedical data measuring illness progression were examined. Life events were assessed by reports on the numbers of lovers, friends, and acquaintances who were diagnosed with AIDS or had died of AIDS and by scores on a checklist of 24 more general serious stressor events. The variables indicating progression of illness among initially asymptomatic men were a drop in T-helper lymphocyte percent (CD4%) between pairs of examinations of at least 25% and onset between examinations of thrush and/or fever lasting a minimum of 2 weeks. RESULTS: The authors found no evidence that serious stressor events have any meaningful effect on symptom onset indicated by either a drop in CD4% or onset of fever or thrush. CONCLUSIONS: There is no need for asymptomatic people with HIV infection to restrict their lives in order to avoid exposure to stressful life experiences or to develop special skills for coping with stress to forestall the progression of HIV illness.

Prevalence of Toxoplasma infection in a cohort of homosexual men at risk of AIDS and toxoplasmic encephalitis.

The purpose of this study was to characterize the epidemiologic, clinical, and laboratory parameters of a cohort of men at risk of AIDS-associated toxoplasmic encephalitis. One hundred seventeen (11%) of the 1,073 participants at the time of enrollment into the Chicago Multicenter AIDS Cohort Study (MACS) were seropositive for Toxoplasma antibodies. Significant differences in prevalence of antibodies between African-American, Hispanic, or white men were not observed (p = 0.49). One hundred one (86%) of the 117 antibody-positive participants had at least one follow-up serology performed and 6 (6%) of the 101 had a significant rise in IgG antibody titer on subsequent visits. Five of six participants with a significant rise in titer were also seropositive for HIV-1 at entry or seroconverted during the study. A trend toward higher IgG Toxoplasma titers and prevalence of IgM antibodies in participants seropositive for HIV-1 was observed, but the differences did not reach statistical significance. There was no evidence that the presence of Toxoplasma infection predisposed to development of CD4+ depletion or AIDS. None of the 183 individuals in the cohort who developed AIDS and who were seronegative for Toxoplasma antibodies developed toxoplasmic encephalitis. In contrast, of the 13 persons who developed AIDS and who were positive for Toxoplasma antibodies, 5 (38%) developed toxoplasmic encephalitis. Prevalence of Toxoplasma antibodies in the MACS population was independent of HIV-1 serostatus. Toxoplasma infection does not appear to predispose to progression of HIV-1 infection. The risk of development of toxoplasmic encephalitis in persons with AIDS and chronic Toxoplasma infection may have been underestimated by previous retrospective studies.