Methamphetamine-Associated Cardiomyopathy: Addressing the Clinical Challenges

Methamphetamine-associated pulmonary arterial hypertension: data from the national biological sample and data repository for pulmonary arterial hypertension (PAH Biobank)

OBJECTIVE

This study compares the clinical and haemodynamic severity of methamphetamine-associated pulmonary arterial hypertension (MA-PAH) with idiopathic pulmonary arterial hypertension (IPAH) and connective tissue-associated pulmonary arterial hypertension (CTD-PAH). It also examines sex differences in clinical and physiological parameters among those with MA-PAH.

DESIGN

This is a cross-sectional study using clinically derived data from the National Biological Sample and Data Repository for Pulmonary Arterial Hypertension (PAH biobank), a US-based registry, to compare clinical and physiological characteristics between males and females with MA-PAH.

POPULATION

The analysis included 1830 patients enrolled in the PAH biobank, with a diagnosis of MA-PAH (n=42), IPAH (n=1073), or CTD-PAH (n=715).

MAIN OUTCOME MEASURES

The study assessed and compared the clinical and haemodynamic parameters of patients with MA-PAH, IPAH and CTD-PAH.

RESULTS

Among the patients analysed, 42 had MA-PAH, with 69.1% being female. There were no statistically significant differences in functional class among patients with MA-PAH, IPAH and CTD-PAH. The per cent predicted 6-min walk distance (6MWD) was comparable between the three groups. Patients with MA-PAH had similar mean pulmonary artery pressure and pulmonary vascular resistance to patients with IPAH but higher compared with patients with CTD-PAH. Male patients with MA-PAH exhibited a worse functional class and lower per cent predicted 6MWD, but no significant differences in haemodynamic findings were observed between the sexes.

CONCLUSION

There were no differences in haemodynamic between MA-PAH and IPAH but we found that MA-PAH differed from CTD-PAH. The study did not find evidence of sex differences in MA-PAH. Further research is necessary to identify risk factors and underlying mechanisms of MA-PAH, particularly considering the increasing prevalence of methamphetamine use. Such investigations will contribute to the development of effective prevention and treatment strategies for this condition.

Methamphetamine-associated heart failure: a systematic review of observational studies

OBJECTIVE

To conduct a systematic review of observational studies on methamphetamine-associated heart failure (MethHF) .

METHODS

Six databases were searched for original publications on the topic. Title/abstract and included full-text publications were reviewed in duplicate. Data extraction and critical appraisal for risk of bias were performed in duplicate.

RESULTS

Twenty-one studies are included in the final analysis. Results could not be combined because of heterogeneity in study design, population, comparator, and outcome assessment. Overall risk of bias is moderate due to the presence of confounders, selection bias and poor matching; overall certainty in the evidence is very low. MethHF is increasing in prevalence, affects diverse racial/ethnic/sociodemographic groups with a male predominance; up to 44% have preserved left-ventricular ejection fraction. MethHF is associated with significant morbidity including worse heart failure symptoms compared with non-methamphetamine related heart failure. Female sex, methamphetamine abstinence and guideline-directed heart failure therapy are associated with improved outcomes. Chamber dimensions on echocardiography and fibrosis on biopsy predict the extent of recovery after abstinence.

CONCLUSIONS

The increasing prevalence of MethHF with associated morbidity underscores the urgent need for well designed prospective studies of people who use methamphetamine to accurately assess the epidemiology, clinical features, disease trajectory and outcomes of MethHF. Methamphetamine abstinence is an integral part of MethHF treatment; increased availability of effective non-pharmacological interventions for treatment of methamphetamine addiction is an essential first step. Availability of effective pharmacological treatment for methamphetamine addiction will further support MethHF treatment. Using harm reduction principles in an integrated addiction/HF treatment programme will bolster efforts to stem the increasing tide of MethHF.

Methamphetamine-associated cardiomyopathy: an addiction medicine perspective

Methamphetamine-associated cardiomyopathy (MaCM) is an increasingly recognised serious complication from methamphetamine (MA) use. It is characterised as the development of otherwise unexplained heart failure in the context of MA use. MaCM predominantly affects a young and vulnerable population with high morbidity and mortality. It is the second leading cause of mortality in patients with MA use disorder (MUD). Our understanding of MaCM pathogenesis is based on observational cohorts and autopsy studies. Currently, the treatment of MaCM is predicated on abstinence. Medical therapies offer some benefit to a minority of patients; however, without abstinence, medical therapies are often ineffective. Abstinence is difficult for most patients to achieve; all clinicians require an understanding of MaCM and how to educate patients on the risks of ongoing use. Where available, referral to addiction medicine specialists to assist with treatment of MUD is recommended. This review aims to: (i) explain the proposed pathologic mechanisms of MaCM; (ii) summarise recent recommendations of the screening and treatment of MaCM; and (iii) highlight the role of addiction medicine in the management of patient with MaCM.