Difficult-to-recruit respondents and their effect on prevalence estimates in an epidemiologic survey

Generous contact efforts were used to recruit 3,004 respondents into the first wave of the St. Louis Epidemiologic Catchment Area (ECA) project, a psychiatric epidemiologic study of the general population, conducted from 1981-1982. These efforts were analyzed to establish which sociodemographic characteristics or current psychiatric disorders were determinants of difficulty in recruitment. Being young, male, black, a nonrural resident, educated, and full-time employed were the demographic characteristics associated with increased contact efforts. Persons currently meeting criteria for an alcohol disorder required almost 20% more contact attempts than those without the disorder; this difficulty lay both in their being less available for an initial contact and refusing at a higher rate once contacted. An optimal recruitment effort cutoff point is provided, and a method is suggested for detecting that optimal point in the course of ongoing studies.     

Immunosuppression by hydroxystilbamidine isethionate, a lysosome-stabilizing, anti-proteolytic, antifungal drug.

Hydroxystilbamidine (HSB) is a potent suppressor of the plaque-forming cell response of mice injected with heterologous erythrocytes. HSB, given in varying doses and injection schedules, suppressed both the primary and secondary immune responses to bovine serum albumin. Apparently the effect is not simply a toxic effect on spleen cells, because there was no appreciable difference in cell numbers between control and HSB-treated mice. The effect of HSB was most apparent in the early phase of the immune respone.     

Quantitation of a cationic antimicrobial granule protein of human polymorphonuclear leukocytes by ELISA

The quantitation of CAP57, a highly hydrophobic, native cationic antigen of human polymorphonuclear leukocytes has been achieved using ELISA. An important feature determining the sensitivity and precision of the ELISA was the reduction of non-specific protein-protein binding, particularly in the inhibition assays, thus eliminating high backgrounds obtained with presently available methodology. Washing of the solid phase-bound antigen and blocking of the non-specific binding sites using a potassium phosphate buffer containing heparin largely contributed to this increased sensitivity. The inhibition assays were conducted using antigen concentrations over the range of 0.9-120 ng. The assay is highly specific and can be performed using monoclonal antibodies and polyclonal antibodies. Non-specific reactions were observed only when high concentrations of antigen (greater than 100 ng) were present in the inhibition mixture. The technique as described is extremely simple, highly reproducible and could be of value in the detection of cationic antimicrobial proteins in the clinical setting in the future.     

The effect of epsilon-aminocaproic acid on HemoSTATUS and kaolin-activated clotting time measurements

New point-of-care assays have been used to identify patients with heparin resistance (i.e. heparin dose response test; Medtronic Blood Management, Parker, CO) and who have platelet dysfunction (i.e. HemoSTATUS; Medtronic Blood Management). We examined the effect of epsilon-aminocaproic acid on results from these two point-of-care tests in patients undergoing cardiac surgery. Twenty patients scheduled for elective cardiac surgical procedures were enrolled in this prospective study. HemoSTATUS clot ratio (% maximal) values in Channels (Ch) 3-6 (Ch 3: 26 +/- 25, Ch 4: 66 +/- 23, Ch 5: 84 +/- 20, Ch 6: 106 +/- 18) obtained after the IV administration of epsilon-aminocaproic acid were similar to values obtained before the administration of this agent (Ch 3: 26 +/- 20, Ch 4: 69 +/- 23, Ch 5: 86 +/- 19, Ch 6: 109 +/- 14). Slope values (86 +/- 23 s x U(-1) x mL(-1)) and projected heparin concentrations (4 +/- 1 U/mL) obtained before the administration of epsilon-aminocaproic acid were similar to slope values (88 +/- 21 s x U(-1) x mL(-1)) and projected heparin concentrations (4 +/- 1 U/mL) values obtained after administration of this agent. Our data indicate that HemoSTATUS clot ratio values and heparin dose response values are not significantly affected after IV dosing of epsilon-aminocaproic acid. Implications: Values from two activated coagulation time-based test systems used to identify significant heparin resistance or platelet dysfunction after cardiopulmonary bypass were not significantly affected by epsilon-aminocaproic acid administered IV.     

Number of Sexual Partners and Associations with Initiation and Intensity of Substance Use

We dissected associations between initiation and intensity of substance use and number of sexual partners using pooled data from high school seniors (weighted n = 13,580) who participated in the 1999–2007 Youth Risk Behavior Surveillance System (YRBS), a cross-sectional, nationally representative survey. In multinomial multivariable logistic regressions, number of sexual partners steadily increased as substance use intensified from never use to experimental/new user to heavy use across all substances for both male and females. Severity of substance use is more closely related to, and thus a better indicator of, higher number of sexual partners than age of substance use onset.     

The specificity of family history of alcohol and drug abuse in cocaine abusers

This study addresses the issue of whether the increased rates of substance-related problems for family members of cocaine abusers are specific for each substance. The present analysis examined the prevalence of problems due to alcohol or drug use separately for mothers, fathers, sisters, and brothers using the Family History Assessment Module. The probands were 343 out-of-treatment subjects with DSM-III-R cocaine disorders who did or did not have additional alcohol and opiate disorders. After accounting for age, race, gender, and antisocial personality, family history of alcohol-related problems had an odds ratio of 1.6 (p <.05) if a participant was alcoholic in addition to abusing cocaine. Specifically, a significantly greater proportion of participants' sisters (p <.001) and brothers (p <.05) had alcohol-related problems if the participant had a history of alcoholism. Among probands who reported opiate abuse or dependence, 38% had relatives with drug-related problems, while participants without opiate abuse or dependence had less than 31% of relatives with drug-related problems (p <.05). However, this association with opiate abuse or dependence and family history of drug-related problems was non-significant after controlling for participants' age, race, gender, treatment status, and antisocial personality diagnosis (odds ratio = 1.4, 95% C.I. = 0.8-2.4). Associations between participants' alcoholism and first-degree relatives' drug-related problems (and vice versa) showed that participants' history of opiate addiction did improve prediction of first-degree relatives' alcohol-related problems, except for participants' brothers. Additional familial risks for alcoholism were seen among siblings of drug abusers who also reported abuse of or dependence on alcohol even after controlling for relatives' ages. Furthermore, parental prevalence of alcohol-related problems were greater when participants had opiate addiction in addition to cocaine addiction. This seems to indicate that opiate addiction in addition to cocaine addiction has particularly strong inheritance patterns. In contrast, parental prevalence of drug-related problems was not greater when participants had alcohol addiction in addition to cocaine addiction. Thus, the cross-substance parent-child familial risk is limited to the dually diagnosed illicit drug.     

Effects of Gender and Comorbidity on Problem Drinking in a Community Sample

We investigated the influence of gender, comorbidity, drinking history, and age on the clinical manifestations of DSM-III alcohol abuse and/or dependence in men and women. The sample was drawn from the National Institute of Mental Health Epidemiologic Catchment Area study, a large-scale, multicenter survey to investigate psychiatric disorders in the community. The results showed that gender and comorbidity had independent effects on problem drinking after drinking history and age had been taken into account. Gender contributed to the age of onset of problem drinking and the rate of its development. Comorbidity, drinking history, and age contributed independently to its severity. The effects of these variables in this community sample paralleled those reported in treatment samples.