Slashdot Mirror
Those Sleeping Pills May Be Killing You
dstates writes "A recent article in in BMJ Open reports a strong association between the use of prescription sleeping pills and mortality. The study used electronic health records for 2.5 million people covered by the Geisinger Health System to find 12 thousand who had been prescribed sleeping pills and a matched set of controls. Death rates were much higher in the patients taking sleeping pills and the risk increases with age. Kudos to the authors for publishing this in an open access journal."
A matched set of controls in your example would be people with comparable heart disease who were not given the medixation. It appears that they have done that in this study:
Models addressing potential confounding of mortality association by health status To further address the possibility that hypnotic-associated hazards were due to use of hypnotic drugs by patients with a greater burden of disease, so that elevated risks of death might be attributable to comorbidities rather than to hypnotic medications, we conducted analyses within subgroups of hypnotic non-users and users defined by diagnoses in specific disease classes (supplemental table 7). Allowing for differences in sample size, hazards in subgroups restricted to patients with specific diseases were generally consistent with the overall findings. We also observed no statistically reliable differences in death HR in subgroups constructed to assess the overall burden of disease by stratifying on the total number of comorbidities diagnosed for each patient, and no reliable differences in death HR comparing groups diagnosed with different numbers of comorbidity classes. Whereas the raw death rate of the user cohort was 4.86 times that of non-user controls (table 1), adjustment for all covariates (eg, age, gender, BMI, smoking) with stratification by comorbidities only reduced the overall HR to 4.56 (95% CI 3.95 to 5.26).
The patients did not know they were being monitored (blind.) The doctors/nurses who entered the charts didn't know their patients' data would be used for this research (double-blind.) The people who analyzed the data, however, had everything upfront to poll and draw whatever conclusions they were looking for. "Using a query into the EHR..." "A further query of this subset..." "For each hypnotic user, we attempted to identify two controls with no record of a hypnotic prescription..." Sounds like they need a triple-blind experimental design.