There are a couple of things about this study that are puzzling to me.
First, I'm a little confused about how to interpret the finding that hypertension related deaths increased, but not stroke or heart attack; I have not been aware of hypertension as a common direct cause of death. For example the textbook "Cardiology Explained" states that: "If untreated, hypertension has serious consequences, including renal disease, myocardial infarction (MI), and cerebrovascular accident." Most general literature that I can recall reading seemed to similarly characterize high blood pressure as a risk factor for other causes of death.
Second, the author of study states "Support for liberal marijuana use is partly due to claims that it is beneficial and possibly not harmful to health." Who is supporting "liberal marijuana use"? Support for "liberal use" is not implied by support for decriminalization.
I hope that press release has left out some sort of context or attribution for this, because it is making it hard for me to take the study seriously.
Here is the meat of the abstract, and a link to the full text of the study:
http://journals.sagepub.com/doi/pdf/10.1177/2047487317723212
"Method:
We linked participants aged 20 years and above, who responded to questions on marijuana use during the 2005 US National Health and Nutrition Examination Survey to data from the 2011 public-use linked mortality file of the National Center for Health Statistics, Centers for Disease Control and Prevention. Only participants eligible for mor- tality follow-up were included. We conducted Cox proportional hazards regression analyses to estimate hazard ratios for hypertension, heart disease, and cerebrovascular mortality due to marijuana use. We controlled for cigarette smoking and other relevant variables.
Results:
Of the 1213 eligible participants 72.5% were presumed to be alive. The total follow-up time was 19,569 person-years. Adjusted hazard ratios for death from hypertension among marijuana users compared to non-marijuana users was 3.42 (95% confidence interval: 1.20–9.79) and for each year of marijuana use was 1.04 (95% confidence interval:1.00–1.07).
Conclusion:
From our results, marijuana use may increase the risk for hypertension mortality. Increased duration of
marijuana use is associated with increased risk of death from hypertension. Recreational marijuana use potentially has cardiovascular adverse effects which needs further investigation."