Mental health, long-term medication adherence, and the control of asthma symptoms among persons exposed to the WTC 9/11 disaster

Abstract

Objective: A positive association between mental health conditions and poor asthma control has been documented in the World Trade Center-exposed population. Whether factors such as medication adherence mediate this association is unknown.

Methods: The study population was drawn from adult participants of the World Trade Center Health Registry Cohort who self-reported as asthmatic after the disaster and who were currently prescribed a long-term control medication (LTCM). Multivariable linear regression was used to estimate the associations between mental health condition (PTSD, depression, or anxiety) and continuous adherence and Asthma Control Test (ACT) scores.

Results: In the study sample of 1,293, 49% were not adherent to their LTCM and two thirds reported poorly or very poorly controlled asthma. Presence of any mental health condition was associated with a 2-point decline in ACT and half a point decrease in adherence scores. However, in the multivariable model, better adherence was statistically significantly associated with slightly worse control.

Conclusions: The total effect of mental health on asthma control was opposite in sign from the product of the paths between mental health and adherence and adherence and asthma control; we therefore found no evidence to support the hypothesis that adherence mediated the negative association between poor mental health and adequate asthma control. More research is needed to understand the complex causal mechanisms that underlie the association between mental and respiratory health.

Keywords:

• Control/management
• epidemiology
• phenotypes
• treatment

Acknowledgments

The authors would like to thank NYC DOHMH employees Robert Brackbill, Mark Farfel, Charon Gwynn, Hannah Jordan, Jiehui Li, and Sukhminder Osahan for their contributions to the design, analysis, and editing of this manuscript.

Declaration of interest

The authors report no conflicts of interest. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIOSH, CDC, or the Department of Health and Human Services.

Additional information

Funding

This publication was supported by Cooperative Agreement Numbers 2U50/OH009739 and 5U50/OH009739 from the National Institute for Occupational Safety and Health (NIOSH) of the Centers for Disease Control and Prevention (CDC); U50/ATU272750 from the Agency for Toxic Substances and Disease Registry (ATSDR, CDC), with support from the National Center for Environmental Health (CDC); and by the New York City Department of Health and Mental Hygiene (NYC DOHMH). Rafael E. de la Hoz’s work was made possible by grant U01 OH010401, from the National Institute for Occupational Safety and Health.