Racial differences in the prevalence of left ventricular hypertrophy among chronic cocaine abusers

A thematic analysis of stress, substance-cue, and neutral/relaxing events to inform approaches for improving treatment among Black adults who use substances

INTRODUCTION

To inform approaches for adapting substance use treatment for Black adults, the aim of this study was to thematically analyze the stressors, triggers for substance use, and neutral/relaxing events reported among Black adults who participated in a lab paradigm.

METHODS

The sample included 36 Black adults (mean age [years] = 37.47, SD = 7.30; 53 % male, 12 (33 %) with alcohol use disorder, 12 (33 %) with cocaine use disorder, and 12 (33 %) healthy controls). All participants provided detailed stimulus and response context information on the most stressful event they experienced in the past year, an event that involved substance use, and a neutral/relaxing event in a structured interview using a scene development questionnaire, and this information was utilized to generate a personalized imagery script for each event using standardized procedures. Thematic analyses identified the key themes reported within scripts.

RESULTS

Consistent with a prior thematic analysis on a majority White sample, we found the following themes for the stress scripts: Relational (Violation, Loss, Parenting, Betrayal, Isolation vs. support), Environmental (Housing, Legal), and Achievement (Employment, Role in household). However, our analyses also resulted in new stress themes: Relational (Violation-Racial Microaggressions) and Institutional (Time Wasted). The substance use scripts consisted of the following trigger themes: Social (Social Facilitation, Socially-Sanctioned Substance Use Event, Exposure to Substance Use Friends/Associates), Internal (Free Time, Boredom, Thoughts of Using Substance, Frustration, Reward), and Environment (Availability of Substance, Celebration, Party Environment, Food, Hot Day, Money/Payday). The neutral/relaxing scripts themes were: Outdoor Activities (Admiring Nature, People Watching, Observing Surroundings, Enjoying the Sun, Playing in the Sand, Walking), Quiet Activities (Silence/Quiet, Prayer, Reading), and Indoor Activities (Radio, Television, Bath/Shower, Bed/Chair, Observing from a Window). We found sex differences across scripts.

CONCLUSIONS

The results suggest that Black people experience unique stressors (e.g., institutional and racial stressors) that are important to consider when modifying treatment to improve outcomes among this group. In addition to stressors, this study also identified high-risk situations involving triggers for use. Taken together these findings suggest targets for the tailoring of coping strategies that could be incorporated for the development of culturally relevant behavioral treatment for SUD.

Predicting cardiovascular risk using a novel risk score in young and middle-age adults with HIV: associations with biomarkers and carotid atherosclerotic plaque

BACKGROUND

Traditional risk factors associated with cardiovascular disease (CVD) include older age, smoking, poor diet, lack of exercise, obesity, high blood pressure, high cholesterol, and family history. Young-to-middle age adults (YMAA) are less often identified as being at risk of CVD, but traditional risk scores primarily target older adults and do not accurately estimate risk among YMAA.

METHODS

This study examined biomarkers associated with CVD risk in YMAA in the context of HIV and cocaine use; risk was assessed by two methods: (1) a relative cardiovascular (CV) risk score that includes several factors and (2) carotid atherosclerotic plaque. Associations between CVD risk (CV risk score and carotid atherosclerotic plaque) and proinflammatory cytokines, markers of immune activation, HIV status, and cocaine use were examined. Participants (N = 506) included people with and without HIV and people who use or do not use cocaine.

RESULTS

Participants' mean age was 36 (SD = 9.53); half (51%) were men. Cocaine use and C-reactive protein were associated with greater relative CV risk scores, but no associations between biomarkers and CV risk emerged. Age and CV risk scores were associated with carotid atherosclerotic plaque, but biomarkers were not. HIV was not associated with CV risk scores or carotid atherosclerotic plaque.

CONCLUSIONS

Among YMAA, CV risk scores may help providers identify lifestyle changes needed among those at risk for CVD before more advanced risk (e.g., atherosclerotic plaque) is identified. Implications are discussed.

Combined pathological effects of cocaine abuse and HIV infection on the cardiovascular system: an autopsy study of 187 cases from the Fulton County Medical Examiner's office

This autopsy study evaluates the possible cumulative effects of cocaine use in HIV-infected adult individuals on cardiovascular tissue. A total of 187 autopsy case reports and available H&E sections of myocardium and coronary arteries were reviewed. Four major study groups were defined: (A) a total of 63 cases positive for cocaine and negative for HIV (COC); (B) 40 cases positive for HIV/AIDS and negative for cocaine (HIV), (C) 23 cases both HIV/AIDS and cocaine (HIV/COC), and (D) a control group of 61 age-, sex- and race-matched, negative for cocaine and for HIV (CONT). The following morphologic and demographic data were analyzed: heart weight, left ventricular hypertrophy, myocardial fibrosis, thickening of the intramyocardial vessels, myocarditis, acute or remote myocardial infarcts (MI), age, sex, and race. Increased frequency of coronary wall and adventitial infiltrates, myocarditis, and thickened intramyocardial vessels present in HIV/COC group (14.5%, 17.4%, and 17.4% vs. 6.5%, 3.3%, and 0% in CONT group) may indicate possible combined and/or cumulative effects of HIV and cocaine on cardiovascular pathology.

Cocaine activates calcium/calmodulin kinase II and causes cardiomyocyte hypertrophy

Cardiac hypertrophy occurs in as many as 47% of normotensive individuals who chronically use cocaine. We investigated the effects of cocaine, in concentrations commonly found in chronic cocaine users, on calcium/calmodulin kinase (CaMK), and whether cocaine can activate CaMK, increase cardiac myocyte protein expression, and cause cardiac hypertrophy in this manner. In series I to III, 0 (control) or cocaine in concentrations of 10 to 10 mol/L was added to cultured adult rat cardiac ventricular myocytes to determine by Western blots and by P incorporation the optimal treatment time and the optimal dose for CaMK activation. In series I, cocaine, 10 mol/L, increased myocyte CaMKII translocation from myocyte soluble to particulate fractions by > or =73 +/- 9% (P < 0.01) in comparison with controls but did not cause the translocation of CaMKI or CaMKIV. In series II and III, cocaine treatment of myocytes for 15 minutes increased maximal CaMKII activity by 86.5 +/- 13.3% (P < 0.001) and a cocaine dose of 5 x 10 mol/L increased CaMKII activity by 169.5 +/- 18.1% (P < 0.001). In series IV we measured by silver staining beta-myosin heavy chain protein (beta-MHC) expression in myocytes before and after cocaine and also CaMK inhibition with KN-62 (1-[N,O-bis-(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenylpiperazine). In these experiments, cocaine, 5x10 mol/L, increased myocyte protein concentration by 29.2 +/- 2.8%, and beta-MHC by 93.2 +/- 8.8% (P < 0.001). In series V and VI, cocaine effects on calcium currents (ICa) and intracellular Ca ([Ca]i) were determined before and after CaMK inhibition with KN-62 in rat myocytes. Cocaine, 10 mol/L, enhanced ICa peak amplitude in a voltage-dependent manner (by 173.9 +/- 14.9% at -20 mV and by 38.4 +/- 6.9% at 0 mV P < 0.01). Cocaine, 10 to 10 mol/L, in series VI promoted Ca transients from myocyte sarcoplasmic reticulum and increased [Ca]i to 607 +/- 141 x 10 mol/L (P < 0.05). KN-62 decreased cocaine-induced myocyte protein expression by 76.6%, and beta-MHC by 66.2% (P < 0.01) and significantly decreased cocaine-induced Ca transients and [Ca]i. We conclude that CaMKII activation is an important mechanism whereby cocaine can cause myocyte hypertrophy.

Cocaine produces cardiac hypertrophy by protein kinase C dependent mechanisms

BACKGROUND

Chronic cocaine users can have as much as a 69% increase in left ventricular muscle mass without associated increases in arterial blood pressure, heart rate, renin, aldosterone, or cortisol. We determined whether cocaine directly increases cardiomyocyte protein content and whether protein kinase C is important in this process.

METHODS AND RESULTS

Adult rat cardiomyocytes were isolated and grown in cultures. In Series I experiments, cocaine, 10(-8) to 10(-6) M, or vehicle, in the absence or presence of phentolamine or metoprolol, was added to each culture and the cells were subsequently harvested. In Series II, cocaine, 10(-6) M, cocaine, 10(-6) M, plus bisindolylmaleimide, 10(-6) M, a protein kinase C inhibitor, or vehicle were added to each culture and the cells subsequently harvested. We determined the total protein content, the content of alpha-myosin and fetal beta-myosin heavy-chain protein, and the presence of protein kinase C isoforms in the cardiomyocyte soluble and particulate fractions. Protein kinase C translocation from the soluble to particulate fraction is indicative of activation. In Series III, we determined the cocaine effects on ERK, SAPK/JNK, and p38. In Series I, cocaine, 10(-8) to 10(-6) M, dose-dependently increased myocyte protein content by as much as 28%+/-2% (P<.001) and fetal beta-myosin heavy-chain protein content by 80%+/-2% (P<.001). Neither phentolamine nor metoprolol inhibited this process. In Series II, we determined that ventricular myocytes contain alpha (alpha), beta (beta), delta (delta), epsilon (epsilon), and zeta (zeta) protein kinase C isoforms. Cocaine, 10(-6) M, caused a 45+/-5% increase (P<.001) in protein kinase Calpha in the particulate fraction. The addition of a protein kinase C inhibitor to the myocyte cultures prevented the cocaine-induced translocation of protein kinase Calpha and limited the increase in beta-myosin heavy-chain protein content by >75% (P<.001). However, cocaine did not increase the phosphorylation of ERK, SAPK/JNK or p38 in Series III.

CONCLUSIONS

Cocaine increases adult cardiomyocyte protein content by protein kinase Calpha-dependent mechanisms, and this process can contribute to the cardiac hypertrophy and cardiomyopathy that results from chronic cocaine use.

Cocaine, HIV, and their cardiovascular effects: is there a role for ACE-inhibitor therapy?

Cocaine abuse and HIV disease each have potentially adverse effects upon the heart and cardiovascular system which may be exacerbated when these risk factors are combined. The development of a safe and effective agent to treat both cocaine addiction and its cardiovascular sequelae, that is well-tolerated by HIV patients, would thus be of considerable clinical utility. In this article we discuss the rationale for the investigation of angiotensin converting enzyme (ACE) inhibitors, commonly used to treat hypertension, for treatment in cocaine-abusing populations, based on their potential to reduce cocaine use by modulating levels of dopamine and corticotropin releasing factor in the brain, and on their ability to reverse cardiovascular and platelet abnormalities. We present preliminary findings from echocardiographic and platelet activation studies in 16 HIV-positive, cocaine abusing patients, as well as tolerability and efficacy studies of the ACE-inhibitor, fosinopril, for the treatment of cocaine abuse in both HIV-positive (n=6) and HIV-negative (n=5) methadone-maintained cocaine abusers. Findings suggest that HIV-positive cocaine-abusing patients possess abnormalities of diastolic heart function and platelet activation that are potentially reversible with ACE-inhibitor therapy. Findings also suggest that fosinopril is well-tolerated regardless of HIV serostatus, does not appear to cause hypotension, and may possess effectiveness for reducing cocaine use. We conclude that ACE-inhibitor therapy may offer a new pharmacologic approach to the treatment of cocaine abuse and its complications, and that controlled research of this class of agents may be promising.

Cocaine increases beta-myosin heavy-chain protein expression in cardiac myocytes

BACKGROUND

As many as 47% of chronic cocaine users develop cardiac ventricular hypertrophy. The presence and degree of cocaine-induced ventricular hypertrophy is not correlated with the use of other substances of abuse such as alcohol or cigarettes. Moreover, this hypertrophy occurs in individuals without sustained increases in arterial blood pressure or heart rate, or increases in the plasma concentration of renin, aldosterone, norepinephrine, or cortisol. Therefore, we investigated whether cocaine, in concentrations commonly found in cocaine users, has any direct effects on the protein content in cardiac ventricular myocytes. We compared the effects of cocaine with norepinephrine, which increases the total protein content, especially beta-myosin heavy-chain contractile protein (beta-MHC), in cardiac ventricular myocytes.

METHODS

Experiments were performed on 30-day-old rat ventricular myocytes suspended in culture media and cultured in flasks. In 12 suspension-culture experiments, cocaine or norepinephrine, in doses of 0 (control) or 10(-6) mol/L was added to each culture and the cells were harvested on day 5. In 16 flask-culture experiments, cocaine or norepinephrine was added to each culture on day 7 in doses of 0 (control-vehicle), 10(-7), or 10(-6) mol/L and the cells were harvested on day 10. The total protein content and the myosin protein expression of the myocytes in each culture were determined. Juvenile and adult rat cardiac myosin protein is predominately alpha-myosin heavy-chain protein (alpha-MHC), whereas beta-MHC occurs primarily in fetal rat hearts.

RESULTS

In the suspension-culture experiments, cocaine, 10(-6) mol/L, increased the cardiomyocyte total protein concentration by 29% +/- 2% (P <.001) and the beta-MHC expression by 81% +/- 10% (P <.01) in comparison with the control myocytes. Cocaine slightly decreased cardiomyocyte alpha-MHC. Norepinephrine increased the total protein concentration by 21% +/- 3% (P <.001) and the beta-MHC expression by 59% +/- 10% (P <.01), but did not increase alpha-MHC expression. In the flask-culture experiments, cocaine, 10(-6) mol/L, maximally increased the total protein concentration by 28% (P <.001), the protein/cell ratio by 57% +/- 10% (P <.01), and the beta-MHC expression by 85% +/- 8% (P <.01). Cocaine slightly decreased alpha-MHC. Norepinephrine, 10(-6) mol/L, maximally increased the total protein concentration by 35%, the protein/cell ratio by 63% +/- 9% (P <.01), and the expression of beta-MHC by 78% +/- 11% (P <. 01). Norepinephrine did not increase alpha-MHC expression. In 18 separate flask-culture experiments, cocaine, 10(-6) mol/L, was added to the cardiomyocyte cultures after the addition of phentolamine (n = 9), in concentrations of 10(-7) to 10(-5) mol/L, or metoprolol (n = 9), in concentrations of 10(-7) to 10(-5) mol/L. Neither phentolamine nor metoprolol inhibited the cocaine-induced increase in cardiomyocyte total protein content or the expression of beta-MHC.

CONCLUSION

Cocaine, similar to norepinephrine, significantly increases the total protein content and the expression of beta-MHC in cardiac ventricular myocytes. In this manner, cocaine may cause cardiac ventricular hypertrophy. This process is not inhibited by alpha- or beta-adrenergic receptor blockade.

Race, baseline characteristics, and clinical outcomes after coronary intervention: The New Approaches in Coronary Interventions (NACI) registry

BACKGROUND

The impact of race and sex on clinical outcomes after percutaneous coronary interventions remains incompletely understood. Specific data on patient demographics, lesion characteristics, and outcomes of black versus white patients are poorly described. To further evaluate these issues, we analyzed the New Approaches in Coronary Interventions (NACI) registry.

METHODS

Patients (200 black, 4279 white) undergoing coronary interventions in the NACI trial were compared. A Cox proportional hazards model was used to determine which baseline demographics were independent risk factors for the combined end point of death, Q-wave myocardial infarction, and coronary artery bypass grafting at 1 year.

RESULTS

Black patients were significantly younger (age 59 +/- 11 vs 63 +/- 11 years; P <.001), more often obese (29.6 +/- 6 vs 27.5 +/- 4.8 kg/m(2); P <.001), female (50% vs 34%; P <.001), diabetic (34% vs 21%; P <.001), and hypertensive (71% vs 52%; P <.001). Black patients were significantly more likely to have single-vessel disease (48% vs 40%; P <.05) and less likely to have undergone coronary artery bypass grafting (26% vs 34%; P <.05). Blacks were significantly more likely to have a discrete lesion (85% vs 62%; P <. 001) with less thrombus (7% vs 12%; P <.05), tortuosity (17% vs 25%; P <.05), and an ulcerated appearance (5% vs 10%; P <.05). Despite these significant baseline differences, no significant difference was seen in the procedural success (80% vs 82%) or major adverse events (death, Q-wave myocardial infarction, any revascularization) at 1 year (39% vs 34%). Predictors of adverse events for white patients included diabetes (relative risk [RR] = 1.24; confidence intervals [CI], 1.0-1.5) and high-risk status (RR = 1.58; CI, 1.26-1. 91). Predictive characteristics of adverse events for black patients included only sex (RR = 3.45; CI, 1.27-9.35; P =.02).

CONCLUSIONS

There are significant differences in baseline characteristics of black patients compared with white patients. Despite these differences in traditional risk factors, they do not affect procedural success or 1-year outcome. In black patients, only sex predicted adverse events. Additional investigation is required to understand the mechanisms for this difference.

The relationship between chronic cocaine or alcohol use and blood pressure in black men during uncomplicated tooth extraction

PURPOSE

The object of this study was to determine whether a history of cocaine or alcohol use is associated with blood pressure changes in patients undergoing an uncomplicated mandibular molar extraction.

PATIENTS AND METHODS

The blood pressure (BP) values of middle-aged (30 to 40 years of age) black men with different chronic drug histories were compared during extraction procedures. The four different groups were 1) no-drug control, (n = 10); 2) alcohol (n = 15); 3) "crack" cocaine (n = 9); and 4) cocaine (n = 22).

RESULTS

The cocaine group's blood pressures were significantly different compared with the blood pressures within the no-drug and alcohol groups (P < .05). The cocaine group's BPs decreased throughout the procedure, and the BPs of the no-drug and alcohol groups rose during administration of the local anesthetic and extraction, and then fell. The BPs of the crack group were highly variable and not significantly different when compared with other groups.

CONCLUSION

There is a paradoxical effect of chronic cocaine use on blood pressure that needs to be considered when treating such patients.